Damien Legallois
email: damien.legallois@unicaen.fr

Laure Chaufourier

Katrien Blanchart

Jean-Jacques Parienti

Annette Belin

Paul Milliez

Rémi Sabatier

Improving quality of care in patients with decompensated acute heart failure using a discharge checklist

Background. -The use of a discharge checklist may decrease heart failure readmission rate.

Aims. -We aimed to evaluate the usefulness of a checklist in patients hospitalized for heart failure, in terms of mortality, cardiovascular mortality and readmission rates, and quality of care, including therapeutic optimization and careplan planning.

Methods. -We prospectively used a discharge checklist in 103 patients hospitalized for heart failure between July 2015 and January 2016. Quality of care and outcomes were compared with a retrospective cohort of 137 patients with same inclusion criteria, hospitalized between June 2014 and December 2014. The primary endpoints were total and cardiovascular mortality and readmissions for heart failure at 6 months. The secondary endpoint was quality of care rendered, measured by evidence-based medications, appropriate medication uptitration and planned discharge care.

Results. -At 6 months, there were no differences between the checklist and control cohorts in the rates of all-cause mortality (10.7% vs 13.1%; P = 0.57), cardiovascular mortality (8.7% vs 10.9%; P = 0.58) and readmission (29.1% vs 32.1%; P = 0.62). Follow-up after discharge was better planned in the checklist group. The use of the checklist yielded therapeutic optimization with a higher dose of beta-blockers and renin-angiotensin-aldosterone system blockers, especially in patients with a reduced left ventricular ejection fraction (< 50%) (P = 0.03 and P = 0.02, respectively).

Conclusions. -The use of a simple discharge checklist in patients with acute heart failure showed no benefit in terms of readmission and mortality rates; however, it yielded better quality of care, including therapeutic optimization and careplan planning.

Résumé

Contexte. -L'utilisation d'une check-list de sortie pourrait diminuer les réhospitalisations pour insuffisance cardiaque aiguë.

Objectifs. -Evaluer l'impact de l'utilisation d'une check-list sur la mortalité, le taux de réhospitalisation pour insuffisance cardiaque, l'optimisation du traitement médical et la planification du suivi. Méthodes. -Une checklist a été utilisée prospectivement chez 103 patients hospitalisés pour insuffisance cardiaque aiguë, entre juillet 2015 à janvier 2016. La prise en charge de ces patients et leur suivi ont été comparés à une cohorte rétrospective de 137 patients (juin à décembre 2014). Les critères de jugement principaux étaient la survenue d'un décès, d'un décès d'origine cardiovasculaire

ou une réhospitalisation pour insuffisance cardiaque à 6 mois. Les critères de jugement secondaires étaient l'optimisation du traitement médical et la planification du suivi.

Résultats. -Il n'existe pas de différence sur la mortalité toutes causes, la mortalité cardiovasculaire et les réhospitalisations pour insuffisance cardiaque à 6 mois : respectivement, 10,7 % vs 13,1 %, P = 0,57 ; 8,7 % vs 10,9 %, P = 0,58 ; 29,1 % vs 32,1 %, P = 0,62, pour le groupe checklist versus groupe contrôle. L'optimisation du traitement est meilleure dans le groupe check-list, en particulier pour les patients ayant une fraction d'éjection ventriculaire gauche altérée < 50 %, où les posologies de bêtabloquants et d'inhibiteurs du système rénine-angiotensine-aldostérone sont significativement plus élevées (P = 0,03 et P = 0,02, respectivement).

Background

Despite recent breakthroughs in medical therapies and interventions, heart failure (HF) remains a major public health problem, with a significant medicoeconomic impact and a poor prognosis. The rates of 30-day readmission still vary from 11% to 18.5% [START_REF] Arora | Etiologies, Trends, and Predictors of 30-Day Readmission in Patients With Heart Failure[END_REF][START_REF] Fudim | Aetiology, timing and clinical predictors of early vs. late readmission following index hospitalization for acute heart failure: insights from ASCEND-HF[END_REF], and nearly half of these hospitalizations occur before the first ambulatory visit [START_REF] Hernandez | Relationship between early physician followup and 30-day readmission among Medicare beneficiaries hospitalized for heart failure[END_REF]. It is estimated that up to 75% of these early readmissions could be avoided [START_REF] Desai | Rehospitalization for heart failure: predict or prevent?[END_REF], and patients who are discharged from hospitals that have higher early follow-up rates have a lower risk of 30-day readmission [START_REF] Hernandez | Relationship between early physician followup and 30-day readmission among Medicare beneficiaries hospitalized for heart failure[END_REF]. As a consequence, the European Society of Cardiology (ESC) HF Guidelines recommend predischarge and long-term management to prevent early readmissions [START_REF] Ponikowski | ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure: The Task Force for the diagnosis and treatment of acute and chronic heart failure of the European Society of Cardiology (ESC). Developed with the special contribution of the Heart Failure Association (HFA) of the ESC[END_REF].

Rehospitalizations are perceived as a correctable source of poor quality of care, poor quality of life in patients with HF and excessive medical costs. Some checklists have been suggested as a tool to assist physicians in the management of discharge of patients with HF [START_REF]Target: HF Strategies and Clinical Tools. Discharge checklist[END_REF][START_REF] Cowie | The Optimize Heart Failure Care Program: Initial lessons from global implementation[END_REF][START_REF]Groupe Insuffisance Cardiaque et Cardiomyopathies of the French Society of Cardiology[END_REF][START_REF] Mebazaa | Acute heart failure and cardiogenic shock: a multidisciplinary practical guidance[END_REF]. However, there are few data on the usefulness of these tools. Basoor et al. demonstrated that the use of a simple predischarge checklist in 48 patients with HF (among 1597 patients admitted with acute HF in the study period) led to better therapeutic optimization and decreased hospitalization rates when compared with 48 matched patients with HF without checklist use [START_REF] Basoor | Decreased readmissions and improved quality of care with the use of an inexpensive checklist in heart failure[END_REF]. An abstract reported a significant decrease in HF readmission rate using an HF discharge checklist in 4879 patients, but the full-text article has not been published [START_REF] Frederick | Using a Discharge Readiness Checklist to Reduce Heart Failure Readmissions[END_REF]. As a consequence, there are no data about the usefulness of a discharge checklist as a daily-basis tool in the management of patients hospitalized for decompensated HF.

We aimed to design a discharge checklist to help physicians with therapeutic optimization and planning discharge coordination in patients with HF, and to evaluate its usefulness in improving quality of care and reducing rehospitalization and mortality rates in this population.

Methods

Checklist

Our checklist was designed according to previous ESC HF Guidelines [START_REF] Mcmurray | ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure 2012: The Task Force for the Diagnosis and Treatment of Acute and Chronic Heart Failure 2012 of the European Society of Cardiology. Developed in collaboration with the Heart Failure Association (HFA) of the ESC[END_REF] in order to promote treatment optimization and the development of a careplan before discharge in patients with decompensated HF. The checklist includes simple clinical and paraclinical variables, as well as lifestyle advice, medication use and uptitration, and follow-up management (Fig. 1). We wanted the checklist to be simple and quick to use. A corrective action may be suggested if a particular point is not optimized.

Patient population

We sought to prospectively include all patients hospitalized for acute decompensated HF from July 2015 to January 2016 in our institution (checklist cohort, Fig. 2). Patients were included only if they were discharged home, whatever the left ventricular ejection fraction (LVEF). Heart failure with altered ejection fraction was defined as HF with either reduced or mid-range LVEF (< 50%) [START_REF] Ponikowski | ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure: The Task Force for the diagnosis and treatment of acute and chronic heart failure of the European Society of Cardiology (ESC). Developed with the special contribution of the Heart Failure Association (HFA) of the ESC[END_REF]. Exclusion criteria included planned cardiac surgery (coronary artery bypass and/or valve replacement), transcatheter aortic valve replacement, reversible causes of HF (e.g. Tako-Tsubo syndrome) and age < 18 years. During this period, recommendations on how to use the checklist were provided regularly to medical staff. The checklist had to be completed 1 or 2 days before the planned discharge, in order to allow therapeutic optimization or follow-up planning. Of course, the checklist was not intended to replace individual medical judgment or individual patient needs, and the attending physician was not enforced to use or follow it for all patients with HF.

A control cohort was included retrospectively in our institution from June 2014 to December 2014, with the same inclusion and exclusion criteria. The checklist was not used in the control cohort (Fig. 2).

For each patient in this control cohort, a checklist was completed retrospectively, using medical records with the latest available data at the time of discharge.

Endpoints

The primary endpoints were rates of mortality, cardiovascular mortality and readmission for HF within 6 months of discharge. The secondary endpoint was quality of care rendered, measured by evidencebased medications, appropriate medication uptitration and planned careplan (e.g. telemedicine).

Statistical analysis

Quantitative variables are described as means ± standard deviations, and were compared using Student's t test or the Wilcoxon rank sum test, as appropriate. Qualitative variables are described as number and percentage, and were compared using Fisher's exact test. Rates of adverse events were compared between groups using Fisher's exact test. We used propensity scores to assemble a matched cohort in which patients from the prospective cohort with a discharge checklist versus patients from the retrospective cohort without a checklist would be balanced on key measured baseline characteristics. A P value < 0.05 was considered significant. All analyses were performed using R, version 3.4.4 (R Foundation for Statistical Computing, Vienna, Austria).

Results

Population characteristics

During the inclusion period for the prospective cohort, 200 patients were hospitalized for decompensated HF. Twenty-four patients were excluded, and the discharge checklist was used in 103 patients (51.5%). We retrospectively included 137 patients in the control cohort. Baseline characteristics are depicted in Table 1. Patients in the checklist cohort were significantly older (80.3 ± 11.8 vs 74.7 ± 12.3 years in the control cohort; P < 0.001). LVEF was higher in the checklist cohort (46.0 ± 12.6% vs 41.0 ± 14.8%; P < 0.01). As a consequence, there were significantly more patients with altered LVEF in the control group (63.5% vs 49.0%; P = 0.02). Baseline characteristics were more balanced when comparing propensity-matched cohorts (Table 1).

Checklist data

The checklist data results are depicted in Table 2. Systolic blood pressure was in the target range at discharge in 122 patients (89.1%) in the control cohort compared with 99 patients (96.1%) in the checklist cohort (P = 0.04). There was a non-significant trend for better control of heart rate in the checklist cohort (P = 0.06). There was no brain natriuretic peptide measurement at discharge in 70.1% of patients in the control group compared with only 8.7% in the checklist group (P < 0.001). There was a non-significant trend for a higher albumin concentration in the checklist cohort (P = 0.06).

Outcomes

During the 6-month follow-up period, 11 patients (10.7%) died in the checklist group compared with 18 (13.1%) in the control group (P = 0.57; Table 3). There was no reduction in cardiovascular death at 6month follow-up in the checklist cohort (n = 9, 8.7%) compared with the control cohort (n = 15, 10.9%), even after adjustment using the propensity score (hazard ratio 0.66, 95% confidence interval 0.27-1.63; P = 0.37). There was no difference between groups regarding HF readmission rate: 30 patients (29.1%) in the checklist group compared with 44 (32.1%) in the control group.

Considering only patients with an LVEF < 50%, six (12.0%) died in the checklist group vs 11 (12.6%) in the control group (P = 0.92; Table 3). There was no reduction in cardiovascular death at 6month follow-up: five patients (10.0%) in the checklist cohort compared with nine patients (10.3%) in the control cohort. Finally, there was a non-significant decrease in HF readmission rate: 10 patients (20.0%) in the checklist group compared with 29 (33.3%) in the control group; hazard ratio 0.50, 95% confidence interval 0.22-1.14; P = 0.10, and P = 0.17 after adjustment using the propensity score.

Quality of care (Table 3)

Regarding medications, uptitration of beta-blockers and angiotensin-converting enzyme inhibitors (ACEIs), angiotensin receptor blockers (ARBs) or angiotensin receptor-neprilysin inhibitor (ARNIs) was better in the checklist group than in the control group: respectively, 67.0% vs 60.6% (P < 0.01 for beta-blockers) and 51.5% vs 40.1% (P < 0.001 for ACEIs/ARBs or ARNIs). The same results were observed in patients with altered LVEF (P = 0.03 and P = 0.02, respectively). Some patients in the checklist cohort with altered LVEF were not treated with beta-blockers (12 patients, 24%) or with ACEIs/ARBs or ARNIs (12 patients, 24%) at discharge. The main reasons were contraindications (e.g. cardiac amyloidosis or acute renal failure), but there was no explanation in two patients (4%) in each case. There were also more patients treated with diuretics at discharge in the checklist cohort (92.2% vs 75.9%; P < 0.001). However, there was no difference regarding mineraloreceptor antagonist uptitration. Follow-up after discharge was better planned in the checklist group, as demonstrated by a medical appointment in the next 30 days in 81.6% vs 32.8% in the control group (P < 0.001). Referral to telemedicine was also significantly higher (35.9% vs 15.3%; P < 0.001).

Discussion

We did not demonstrate a reduction in mortality or HF readmission rates using our discharge checklist.

However, the predischarge use of a quality-improvement HF checklist leads to a higher proportion of patients taking evidence-based and uptitrated therapies.

Our population had a high rate of readmission for HF at 6 months (30.8%), which is higher than in the ESC-HF-LT registry, which included 4052 patients hospitalized for decompensated acute HF from 2011 to 2015 [START_REF] Chioncel | Clinical phenotypes and outcome of patients hospitalized for acute heart failure: the ESC Heart Failure Long-Term Registry[END_REF]. This registry reported a 1-year all-cause death rate of 27.2% and a 1-year rehospitalization rate of 29.91%. In this registry, 34.9% of patients were aged > 75 years, and the mean LVEF was 37.3% (18.5% of patients had HF with preserved [> 50%] LVEF [HFpEF]). Our patients were older (mean age: 77 years) and were more likely to have HFpEF (43%). HFpEF is usually associated with significant co-morbidities and older age, and this may explain in part the high rate of readmission we observed.

The present study did not demonstrate that the use of a standardized discharge checklist improves outcomes in patients hospitalized for decompensated acute HF. Previously, Basoor et al. [START_REF] Basoor | Decreased readmissions and improved quality of care with the use of an inexpensive checklist in heart failure[END_REF] showed that the use of a discharge checklist decreased 6-month readmission rates (23% in the checklist group compared with 42% in the control cohort). Some explanations can be advanced to explain this difference. First, the population was different from ours, as the mean LVEF was 40% in the checklist group compared with 46% in our checklist cohort. Patients with preserved or mid-range LVEF tend to be older and have more co-morbidities. Our checklist and the checklist by Basoor et al. were built in order to avoid cardiovascular triggering factors of acute HF, such as arrhythmias or noncompliance with diet. There are more evidence-based data about the treatment of patients with HF with reduced LVEF than with HFpEF [START_REF] Ponikowski | ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure: The Task Force for the diagnosis and treatment of acute and chronic heart failure of the European Society of Cardiology (ESC). Developed with the special contribution of the Heart Failure Association (HFA) of the ESC[END_REF], as no randomized clinical trial has shown better survival in patients with HFpEF. As a consequence, a discharge checklist may be less effective in patients with HFpEF. It may be useful to include items about non-cardiovascular triggering factors, frailty and comorbidities in this specific population. Second, our discharge checklist was used in a significant proportion (51.5%) of patients hospitalized for decompensated acute HF during the period of inclusion. This result is significantly higher than in the study by Basoor et al., where the checklist was used in 48 patients randomly selected from 1597 patients (3%) admitted with decompensated acute HF [START_REF] Basoor | Decreased readmissions and improved quality of care with the use of an inexpensive checklist in heart failure[END_REF]. We aimed to design a simple checklist that could be used in all patients hospitalized for acute HF. Our physicians were encouraged, but not enforced, to use the checklist for all patients with HF. The proposed correcting action was not mandatory, and there was some checklist failure, as about 8% of patients with altered LVEF had neither a beta-blocker nor an ACEI/ARB or ARNI at discharge, without clear reason. Despite being simple and taking approximately only 5 minutes per patient discharge to complete, the use of such a tool may be too time-consuming in a daily setting.

We demonstrated a higher use of beta-blockers and renin-angiotensin-aldosterone system blockers at discharge in the checklist group (68.9% and 67%, respectively) compared with the control group, especially in patients with HF with reduced LVEF. Tuppin et al. showed that 57.7% and 71.4% of patients aged between 70 and 79 years were treated with beta-blockers and renin-angiotensinaldosterone system blockers, respectively, 1 month after discharge [START_REF] Tuppin | Two-year outcome of patients after a first hospitalization for heart failure: A national observational study[END_REF]. Patients have to leave hospital with the most optimized HF treatment possible, as there is little improvement in medications between discharge and follow-up consultation [START_REF] Solal | Optimization of heart FailUre medical Treatment after hospital discharge according to left ventricUlaR Ejection fraction: the FUTURE survey[END_REF]. Moreover, it has been demonstrated that adherence to HF process measures for treatment is significantly associated with survival in outpatients with HF [START_REF] Fonarow | Associations between outpatient heart failure process-of-care measures and mortality[END_REF]. Finally, diuretics were more often prescribed at discharge in the checklist group (92.2% vs 75.9% in the control group; P < 0.001). We observed in our control cohort that diuretics were often suspended because of worsening of renal function, and were not resumed at the time of discharge.

However, this treatment improves congestion, and is the only therapy recommended in patients with HF with preserved or mid-range LVEF in order to alleviate symptoms and signs [START_REF] Ponikowski | ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure: The Task Force for the diagnosis and treatment of acute and chronic heart failure of the European Society of Cardiology (ESC). Developed with the special contribution of the Heart Failure Association (HFA) of the ESC[END_REF]. This mistake in the careplan of patients could be easily prevented by the use of a simple tool like a checklist.

We observed a higher referral to telemedicine and a higher proportion of patients with a planned medical appointment at discharge in the checklist group. This is particularly important, as most HF readmissions occur within 30 days of hospitalization [START_REF] Desai | Intensive Management to Reduce Hospitalizations in Patients With Heart Failure[END_REF]. Also, the American Heart Association has emphasized the importance of effective handover care from inpatient to posthospital providers in the careplan of patients with HF [START_REF] Bradley | Hospital strategies associated with 30-day readmission rates for patients with heart failure[END_REF].

Study limitations

Our study has some limitations. First, it was a single-centre observational study with a relatively small number of patients, and thus residual confounding may persist, despite propensity score matching. It is likely that the sample size was unpowered for the detection of a significant difference in readmission and mortality endpoints. Second, we compared a cohort of patients with a previous one from the same centre, which may have led to different therapeutic approaches. Third, we did not assess if the use of the checklist led to specific modification of therapies or the careplan for a given patient. This point is important, as it may differentiate between a checklist where a corrective action is mandatory (e.g. the WHO's Safe Surgery Saves Lives programme [START_REF] Haynes | A surgical safety checklist to reduce morbidity and mortality in a global population[END_REF]) and a reminder. It is also possible that as inclusions occur, practitioners may become accustomed to verifying the checklist variables. However, the use of a checklist may be useful even in a trained team, in order to maintain a high level of skill and to standardize performance (e.g. the use of aircraft checklists by flight crews [START_REF] Clay-Williams | Back to basics: checklists in aviation and healthcare[END_REF]). A multicentre randomized approach where the beginning of the use of the checklist in all patients is random from one centre to another could help to limit these biases and to assess the changes in the behaviour of the HF team. Fourth, the checklist was not used in all patients admitted for decompensated acute HF, as physicians were not enforced to use it. Fifth, the checklist was used in an overall heterogeneous HF population, including patients with mid-range or preserved LVEF. In these patients, there are still no clear guidelines about therapeutic optimization, and readmissions may be more difficult to prevent.

Conclusions

The use of a simple discharge checklist yielded a better quality of care in patients hospitalized for decompensated acute HF, despite showing no significant improvement in readmission and mortality rates. a When two P values are displayed, the first compared the two overall populations and the second compared only patients with LVEF < 50%.

b Percentages may add up to > 100% because of multiple trigger factors or follow-up careplans.

c Percentages may not add up to 100% because of rounding.

d Only patients with an available BNP measurement were compared. c There were 49 patients in each cohort with propensity score matching as exact LVEF was not available in one patient.

  Abbreviations: ACEI, angiotensin-converting enzyme inhibitor; ARB, angiotensin receptor blocker; ARNI, angiotensin receptor-neprilysin inhibitor; ESC, European Society of Cardiology; HF, heart failure; HFpEF, heart failure with preserved ejection fraction; LVEF, left ventricular ejection fraction.

Figure 1 .

 1 Figure 1. Discharge checklist. The cut-off value between preserved and altered left ventricular ejection fraction (LVEF) was set to 45% (see checklist) during the inclusion period (until February 2016), but analyses were performed with a 50% cut-off level. AHF: acute heart failure; ACE-I: angiotensinconverting enzyme inhibitor; ARB: angiotensin receptor blocker; ARNI: angiotensin receptor-neprilysin inhibitor; BNP: brain natriuretic peptide; CRT: cardiac resynchronization therapy; ECG: electrocardiogram; HF: heart failure; HR: heart rate; ICD: implantable cardioverter defibrillator; IV: intravenous; MR: mineraloreceptor; NYHA: New York Heart Association; SBP: systolic blood pressure; SCAD: Suivi Cardiologique à Distance.

Figure 2 .

 2 Figure 2. Flow chart of enrolment and 6-month outcomes. AHF: acute heart failure; CL: checklist, CV: cardiovascular.

  Data are expressed as number (%) unless otherwise indicated. CI: confidence interval; HF: heart failure; HR: hazard ratio; LVEF: left ventricular ejection fraction. a Checklist cohort (n = 103); control cohort (n = 137). b Checklist cohort (n = 50); control cohort (n = 87).

Table 1

 1 Baseline characteristics.

		Checklist	Control	Standardized	P	Propensity-matched	Propensity-matched	Standardized	P
		cohort	cohort	difference		checklist cohort a	control cohort a	difference
		(n = 103)	(n = 137)			(n = 102)	(n = 102)
	Age (years)	80.3 ± 11.8	74.7 ± 12.3	0.47	< 0.001	80.2 ± 11.8	78.2 ± 10.7	0.18	0.21
	Male sex	51 (49.5)	84 (61.3)	-0.24	0.07	50 (49.0)	59 (57.8)	-0.18	0.26
	LVEF (%)	46.0 ± 12.6	41.0 ± 14.8	0.37	< 0.01	46.0 ± 12.6	44.9 ± 13.5	0.08	0.38
	LVEF < 50% b	50 (49.0)	87 (63.5)	-0.30	0.02	49 (48.0)	57 (55.9)	-0.16	0.33
	Heart rate (bpm)	74 ± 15	76 ± 16	-0.14	0.29	74 ± 15	75 ± 14	-0.07	0.76
	Systolic BP (mmHg)	123 ± 20	120 ± 23	0.12	0.27	123 ± 20	123 ± 22	0.01	0.88
	Creatinine (μmol/L)	121.0 ± 52.3	117.3 ± 47.1	0.08	0.56	121.1 ± 52.6	119.1 ± 47.6	0.04	0.40
	GFR (mL/min per 1.73m 2 )	50.2 ± 19.5	54.7 ± 19.8	-0.23	0.08	50.1 ± 19.6	52.4 ± 19.3	-0.12	0.18

Data are expressed as mean ± standard deviation or number (%). BP: blood pressure; GFR: glomerular filtration rate; LVEF: left ventricular ejection fraction. a There were 102 patients in each cohort with propensity score matching because exact LVEF was not available in one patient.

b Checklist cohort (n = 102); control cohort (n = 137).

Table 2

 2 Checklist data. angiotensin receptor-neprilysin inhibitor; BNP: brain natriuretic peptide; BP: blood pressure; HF: acute heart failure; MRA: mineraloreceptor antagonist.

	Checklist cohort		Control cohort	P a
	Overall	LVEF < 50%	Overall	LVEF < 50%
	(n = 103)	(n = 50)	(n = 137)	(n = 87)

Data are expressed as number (%). ACEI: angiotensin-converting enzyme inhibitor; ACS: acute coronary syndrome; ARB: angiotensin receptor blocker; ARNI:

Table 3

 3 Outcomes at 6 months

	Checklist cohort	Control cohort	HR (95% CI)	P

Sources of funding

None.

Disclosure of interest

The authors declare that they have no conflicts of interest concerning this article.


Mickaël Artuso
email: mickael.artuso@gmail.comnepasutiliser

Virginie Mas

Brice Ilharreborde

Keyvan Mazda

Pascal Jehanno

Place du fixateur externe dans la prise en charge postopératoire des syndactylies complexes pédiatriques. À propos de 18 patients

Keywords: Syndactylie complexe, Pansement, Fixateur externe, Soins Post-Opératoires NIVEAU DE PREUVE: IV, étude observationnelle rétrospective Complex syndactyly, Dressing, External Fixator, Post-Operative Care

INTRODUCTION

Les syndactylies congénitales complètes complexes (SCCC) sont définies par l'accolement complet de deux ou plusieurs doigts, associé à une fusion tissulaire unguéale et/ou osseuse plus ou moins étendue [START_REF] Kay | Deformities of the Hand and Fingers, Syndactylies, Green's Operative Hand Surgery[END_REF][START_REF] Abid | Malformations congénitales de la main[END_REF][START_REF] Swanson | A classification for congenital malformations of the hand[END_REF][START_REF] Swanson | A classification for congenital limb malformations[END_REF] .

Le taux de complications post-opératoires précoces après chirurgie première ou reprise chirurgicale est élevé (5,2% à 25% selon les séries) [START_REF] Mcquillan | Incidence of Acute Complications Following Surgery for Syndactyly and Polydactyly: An Analysis of the National Surgical Quality Improvement Program Database from 2012 to 2014[END_REF][6][START_REF] Barabás | Results of syndactyly release using a modification of the Flatt technique[END_REF] . Ce sont la macération, l'avancée de la commissure, l'infection du site opératoire, la nécrose d'un lambeau local ou d'une greffe de peau.

La prise en charge chirurgicale des syndactylies est bien codifiée [START_REF] Dautel | Malformations congénitales des doigts longs[END_REF][START_REF] Braun | Syndactyly Release[END_REF][START_REF] Samson | Syndactyly[END_REF][START_REF] Withey | The open finger technique for the release of syndactyly[END_REF][START_REF] Mallet | Comparative study of 2 commissural dorsal flap techniques for the treatment of congenital syndactyly[END_REF][START_REF] Yildirim | Correction of syndactyly using a dorsal separated V-Y advancement flap and a volar triangular flap in adults[END_REF] , que ce soit le choix des incisions, l'utilisation de greffe cutanée et de lambeaux locaux. Cependant les soins post-opératoires ne font l'objet que de peu de description dans la littérature, sans consensus retrouvé [START_REF] Dautel | Malformations congénitales des doigts longs[END_REF][START_REF] Braun | Syndactyly Release[END_REF][START_REF] Mallet | Comparative study of 2 commissural dorsal flap techniques for the treatment of congenital syndactyly[END_REF][START_REF] Chevaleraud | Anaesthesia for the hand surgery in patients with diystrophic epidermolysis bullosa[END_REF][START_REF] Kamath | A novel method of using mini external fixator for maintaining web space after the release of contracture and syndactyly[END_REF] .

Devant cette constatation nous proposons l'utilisation d'une stabilisation externe temporaire des doigts et de la commissure.

HYPOTHESE

L'utilisation d'un fixateur externe après libération d'une SCCC permet d'alléger les soins postopératoires et de diminuer le taux de complications.

MATÉRIEL ET MÉTHODES

La série

Il s'agit d'une étude rétrospective, monocentrique menée de Janvier 2016 à Octobre 2017, chez 18 enfants (10 garçons et 8 filles) présentant 22 SCCC (4 enfants présentaient 2 syndactylies). Il s'agissait d'une chirurgie première pour 13 enfants et d'une reprise chirurgicale pour 5 enfants. Les causes de reprise chirurgicale étaient une macération locale compliquée de perte de greffe cutanée et/ou des lambeaux locaux pour 3 enfants et une récidive commissurale pour 2 autres enfants. Les patients présentant des syndactylies simples ou incomplètes étaient exclus car ces pathologies ne présentent pas les mêmes taux de complications post-opératoires ni le même recours systématique aux greffes cutanées.

Huit patients présentaient un syndrome génétique polymalformatif (syndrome d'Apert 5 fois et syndrome de Poland 3 fois). Ces huit patients ainsi qu'un neuvième autre présentaient une SCCC compliquée avec de sévères anomalies osseuses (main en sabot, phalange delta, phalange manquante, synostose étendue, …) L'âge moyen était de 14 mois (6 à 36 ; médiane : 12,5). Le suivi moyen était de 13,3 semaines (3 à 41 ; médiane : 10,5).

Le consentement éclairé des parents était recueilli en consultation préopératoire. Des informations étaient données concernant l'apparence et la taille du fixateur externe (photographies) ainsi que les modalités de soins et de suivi post-opératoires.

Chaque patient avait une évaluation préopératoire clinique et radiologique des mains par le chirurgien. En cas de syndrome polymalformatif, une évaluation multidisciplinaire avait lieu. Le suivi était réalisé par un seul chirurgien et des infirmiers dédiés aux soins de pansement en consultation à l'hôpital.

Intervention et soins post-opératoires

La libération de syndactylie était réalisée par des incisions de Cronin avec réalisation d'un lambeau en oméga commissural dorsal [START_REF] Mallet | Comparative study of 2 commissural dorsal flap techniques for the treatment of congenital syndactyly[END_REF] . Un lambeau de Buck-Gramcko [START_REF] Buck-Gramcko | Congenital malformations: syndactyly and related deformities[END_REF][START_REF] Golash | Nail fold creation in complete syndactyly using Buck-Gramcko pulp flaps[END_REF] était réalisé en cas de reconstruction du bourrelet péri-unguéal. Une greffe de peau totale était prélevée à la face antérieure du poignet ou plus rarement au pli de l'aine. Les interventions se déroulaient sous garrot au bras (pression du garrot = pression systolique X 2), relâché avant la mise en place de la greffe et de la confection du pansement.

Après la libération, une fixation temporaire des articulations interphalangiennes proximales et distales des 2 doigts était réalisée par des broches de Kirschner de 10/10 ème introduites à la poignée américaine. Les broches étaient courbées et connectées entre elles pour maintenir les doigts écartés et immobiles (Figures 1 et 2). Le pansement était réalisé en fin d'intervention avec une interface siliconée antiadhésive, des compresses, et maintenu par une bande de crêpe. Il n'était pas réalisé de radiographies post-opératoires.

Les antalgiques post-opératoires étaient le paracétamol et l'ibuprofène en dosepoids pour respectivement 21 et 3 jours.

Les pansements étaient refaits à l'hôpital en consultation 2 fois par semaine, en présence des parents et pour une durée de 3-4 semaines selon la cicatrisation. Le chirurgien revoyait les patients une fois par semaine. Les pansements étaient réalisés par les infirmiers de consultation; les infirmiers n'avaient pas reçu de formation spécifique à ce pansement et devaient respecter les prescriptions de consommables (identiques au pansement du bloc).

Les enfants devaient prendre le traitement antalgique une heure avant le soin. Les broches étaient retirées par le chirurgien avec une pince tire-broche 21 jours après l'intervention.

Après cicatrisation, les parents devaient appliquer une crème hydratante (glycérol, paraffine, vaseline) pendant 2 semaines sur les mains de l'enfant.

L'auto-rééducation était spontanée et motivée si besoin par le jeu. Le suivi clinique se poursuivait tous les 2 mois.

A chaque pansement, des questionnaires écrits d'évaluation (Figure 3) devaient être complétés par les parents et les infirmiers pour mesurer plusieurs paramètres. Les questions avaient été formulées avec le psychologue de l'hôpital. Chaque paramètre était auto-coté sur une échelle graduée de 0 à 10.

La douleur des enfants était estimée par l'infirmier avec une échelle d'hétéroévaluation : l'échelle FLACC [START_REF] Merkel | The FLACC: a behavioral scale for scoring postoperative pain in young children[END_REF] (Tableau 1).

La présence de macération ou d'infection locale, la nécrose d'un lambeau ou d'une greffe étaient relevés et comptabilisés.

RÉSULTATS

Au total 113 pansements ont été réalisés (6,3 pansements par enfant). La durée moyenne de la réfection de pansement était de 13 minutes (10 à 16) pour les premiers et 10 minutes (7 à 13) pour les derniers. Aucun patient n'a été perdu de vue.

Aucun patient n'a présenté de macération et aucun n'a présenté d'échec de lambeau local ou de greffe.

La seule complication a été une réaction cutanée (rougeur et écoulement clair) au 16 ème jour post-opératoire au point d'entrée d'une broche, résolutive à l'ablation de la broche sans antibiothérapie.

Concernant la douleur (Tableau 2) évaluée selon l'échelle FLACC, la moyenne était de 4,2/10 pour le premier pansement et décroissait jusqu'à 1,3/10 pour le dernier. Le recours au MEOPA (Mélange Equimolaire Oxygène Protoxyde d'Azote) pendant les soins n'a pas été nécessaire.

Les réponses aux autres questionnaires d'évaluation sont données dans le tableau 2. Elles montrent une diminution nette des paramètres étudiés entre le 1 er et le dernier pansement.

DISCUSSION

Dans cette série, l'utilisation du fixateur externe a permis de prévenir les complications post-opératoires : notre hypothèse est confirmée.

Les soins post-opératoires font partie intégrante du suivi des syndactylies congénitales complètes et plus particulièrement des SCCC où le taux de complications dépasse 1 patient sur 20. Peu de descriptions de ces soins sont retrouvées dans la littérature [START_REF] Dautel | Malformations congénitales des doigts longs[END_REF][START_REF] Braun | Syndactyly Release[END_REF][START_REF] Mallet | Comparative study of 2 commissural dorsal flap techniques for the treatment of congenital syndactyly[END_REF][START_REF] Chevaleraud | Anaesthesia for the hand surgery in patients with diystrophic epidermolysis bullosa[END_REF][START_REF] Kamath | A novel method of using mini external fixator for maintaining web space after the release of contracture and syndactyly[END_REF] .

Nos premières indications de fixateur externe étaient réservées aux reprises chirurgicales. Les parents avaient déjà une expérience du suivi post-opératoire classique. Les bons résultats et retours de satisfaction des parents (mettant en évidence une réelle différence concernant les soins post-opératoires précoces et la douleur de l'enfant au changement de pansement) nous ont conduits à élargir cette technique de stabilisation externe à toutes les SCCC.

L'indication restreinte aux SCCC (notamment celles incluses dans un syndrome polymalformatif) était justifiée par les travaux de McQuillan [START_REF] Mcquillan | Incidence of Acute Complications Following Surgery for Syndactyly and Polydactyly: An Analysis of the National Surgical Quality Improvement Program Database from 2012 to 2014[END_REF] (5,2% de complications à 30 jours après libération des SCCC contre 2,3% pour les syndactylies simples), de Bulic [6] (12% de complications), de Barabas [START_REF] Barabás | Results of syndactyly release using a modification of the Flatt technique[END_REF] (25%). De même, dans ces syndromes, les SCCC sont souvent compliquées de sévères malformations osseuses avec nécessité de greffes de peau étendues et de lambeaux locaux complexes. Ceci justifiait le recours au fixateur externe pour assurer une survie optimale de ces greffes et lambeaux (aération, diminution de la macération et des forces de cisaillement).

La réfection des pansements à une telle fréquence, discutée par certaines équipes sans preuve [START_REF] Dautel | Malformations congénitales des doigts longs[END_REF][START_REF] Braun | Syndactyly Release[END_REF][START_REF] Mallet | Comparative study of 2 commissural dorsal flap techniques for the treatment of congenital syndactyly[END_REF][START_REF] Chevaleraud | Anaesthesia for the hand surgery in patients with diystrophic epidermolysis bullosa[END_REF][START_REF] Kamath | A novel method of using mini external fixator for maintaining web space after the release of contracture and syndactyly[END_REF] , était motivée par le taux élevé de macération avec les pansements non changés ou avec immobilisation plâtrée. En effet, la peau infantile, de par ses propriétés histologiques [START_REF] Leung | Biology and Function of Fetal and Pediatric Skin[END_REF] (exsudation et sudation accrues, pH plus élevé qu'une peau adulte), nécessite des soins plus réguliers. Nous admettons que cette fréquence de soins en milieu hospitalier représente une contrainte pour les familles. Réduire la fréquence des pansements à un par semaine nous paraît sans conséquence sur les résultats de la chirurgie. Nous pensons que ces soins sont réalisables en ville par des infirmiers libéraux et que la formation sur ce point serait courte et facile à organiser via une fiche descriptive donnée au patient.

L'analyse des questionnaires montre chez les parents une baisse de l'appréhension aux soins au fur et à mesure des soins post-opératoires consécutifs. Les infirmiers décrivaient une approche technique plus simplifiée et plus rapide. L'utilisation de l'échelle FLACC de douleur chez l'enfant a montré que le fixateur externe participe à diminuer la douleur lors des soins.

Aucune complication à type de macération, reprise chirurgicale, récidive commissurale, perte de greffe ou nécrose de lambeau n'a été observée.

Ce travail étant une étude pilote avec une courte série de patients, les résultats ne peuvent être statistiquement significatifs.

Cette étude n'est pas la première à utiliser un fixateur en post-opératoire des cures de syndactylies ; Glicenstein [START_REF] Chevaleraud | Anaesthesia for the hand surgery in patients with diystrophic epidermolysis bullosa[END_REF] et Kamath [START_REF] Kamath | A novel method of using mini external fixator for maintaining web space after the release of contracture and syndactyly[END_REF] rapportent une technique similaire, pour les prises en charge des épidermolyses bulleuses ou des syndactylies post-brûlures. Ils utilisent des systèmes plus volumineux et indiquent avoir une réduction de la macération et un taux d'infection insignifiant, sans toutefois donner de valeurs chiffrées. Le fixateur externe que nous décrivons est utilisé uniquement sur des enfants, il est moins encombrant et facilement accepté par les familles. Notre étude est la première à proposer des résultats chiffrés dans ce type de suivi post opératoire.

Certains auteurs préconisent l'absence de réfection de pansement pendant 2 à 3 semaines [START_REF] Dautel | Malformations congénitales des doigts longs[END_REF][START_REF] Braun | Syndactyly Release[END_REF] (Pansement constitué d'interface siliconée, compresses tissées avec parfois protection cotonnée renforcée par immobilisation plâtrée). Aucune donnée clinique ou chiffrée, aucun discernement dans le type de syndactylie traitée n'apparaît dans ces articles.

Dans le cas d'un pansement de main pédiatrique avec ou sans plâtre, laissé trois semaines, le risque de macération est élevé et peut entrainer un retard de cicatrisation voire une infection locale ou un échec chirurgical avec nécessité de reprise. À l'inverse, un pansement refait trop fréquemment peut induire des forces de cisaillements lors des mouvements de l'enfant risquant de décoller un lambeau ou une greffe de peau.

Les soins post-opératoires des SCCC nécessitent des précautions particulières et la fixation externe permet de faciliter cette étape de la prise en charge des patients. Apert Syndrome with third web-space surgery: X-ray (A), preoperative (B,C), immediate (D,E) and fourth week (F,G) postoperative aspect.

Tableau 2 :Figure 1 :

 21 Figure 1 : Libération de la troisième commissure dans un syndrome d'Apert ; aspect radiologique (A), clinique préopératoire (B,C), post-opératoire immédiat (D,E)et à 4 semaines (F,G).

Figure 2 :

 2 Figure 2 : Libération de la première commissure dans un syndrome d'Apert : aspect clinique préopératoire (A,B), post-opératoire immédiat (C,D), à 2 semaines (E) et 4 semaines (F,G,H) .Apert Syndrome with first web-space surgery; preoperative (A,B), immediate postoperative (C,D), second (E) and fourth week (F,G,H) postoperative aspect.

Figure 3 :

 3 Figure 3: Questionnaire.

CONCLUSION

La stabilisation externe dans la prise en charge post-opératoire des SCCC semble, à la lueur de cette étude, réduire la douleur des enfants, faciliter les soins et prévenir les complications post-opératoires. Elle limite la macération en gardant les doigts écartés et prévient les complications telles que la perte de greffe, la nécrose de lambeau ou la récidive. Elle reste, dans notre pratique, limitée à certaines indications mais doit, à notre sens, être envisagée si les soins post-opératoires risquent d'être compliqués. Des études ultérieures sont nécessaires afin d'évaluer le suivi à long terme de ces patients.


Jean-Damien Metaizeau
email: jd.metaizeau@yahoo.fr

Delphy Denis
email: denisdelphy@hotmail.fr

David Louis

New Femoral Derotation Technique Based on Guided Growth in Children

Keywords: Torsional growth modulation, Guiding rotational growth, Children

Derotation osteotomy is the only available treatment for medial femoral torsion in paediatric patients. To eliminate the need for post-operative immobilisation and to allow immediate weight bearing, we suggest a new technique that guides femoral growth. The goal is to convert part of the axial growth into rotation by placing a system composed of two screws and a cable around the distal femoral physis. We used this percutaneous technique to treat 20 knees in 11 children. The preliminary outcomes indicate good efficacy with about 1.2° of derotation per month and a total mean derotation of 25° over 22 months. Post-operative stiffness was the main complication but resolved with physical therapy. This technique may therefore constitute an alternative to derotation osteotomy.

Introduction

Femoral derotation osteotomy is currently the only available treatment for correcting rotational malalignment [START_REF] Rippstein | Determination of the antetorsion of the femur neck by means of two x-ray pictures[END_REF][START_REF] Accadbled | In-toeing and out-toeing[END_REF][START_REF] Fabry | Torsion of the femur. A follow-up study in normal and abnormal conditions[END_REF]. Although effective, this method exhibits the drawbacks associated with all femoral osteotomies (4-10).

We drew inspiration from the use of epiphysiodesis to correct lower limb length discrepancies and coronal malalignment [START_REF] Metaizeau | Percutaneous epiphysiodesis using transphyseal screws (PETS)[END_REF][START_REF] Song | Percutaneous epiphysiodesis using transphyseal screws in the management of leg length discrepancy: optimal operation timing and techniques to avoid complications[END_REF][START_REF] Inan | Efficacy and safety of percutaneous epiphysiodesis[END_REF] to devise a percutaneous technique designed to guide femoral growth in a manner that gradually corrects rotational malalignment. This technique is less invasive and provides a better risk/benefit ratio compared to femoral derotation osteotomy. Results reported in 2013 by Arami et al. [START_REF] Arami | Guiding femoral rotational growth in an animal model[END_REF] established that torsional growth could be modulated in rabbits by positioning eight-plates on the distal femur, and similar findings were described by Lazarus et al. in 2018 (15).

Operative technique

The technique is designed to guide growth towards derotation by placing a system composed of two cannulated screws and a cable on either side of the distal femoral physis.

Growth can only occur vertically, as is the case under normal conditions, and is therefore guided towards derotation. Figure 1 shows the device on a left femur. The cable passes through the screws and is then locked on itself under tension. During growth, the tension of the cable causes a rotational movement (laterally in the example shown). Thus, part of the vertical growth is converted to rotational growth. Here, we describe the technique used to obtain lateral derotation, which is the most common situation.

The patient is supine. Fluoroscopic guidance is used. A guidewire is inserted alongside and parallel to the physis, in the middle of the bone in the sagittal plane (Fig. 2 and3). An external fixator ring is centred on the guidewire on the antero-posterior and lateral views so that the centre of the ring coincides with the centre of the physis (Fig. 4 and5).

A transfixing guide pin is then inserted percutaneously. The entry site is just distal to the growth plate and slightly lateral to the lateral edge of the trochlea. The pin is inserted in the anterior-to-posterior direction, at an angle of about 30° relative to the guidewire, and parallel to the physis. Care is taken to ensure that the guide pin exits the ring at a point exactly opposite the entry site. This precaution is important, as the pins must cross each other at the centre of the bone to eliminate the risk of axial deviation (Fig. 6).

Then, a second transfixing guide pin is inserted percutaneously through a lateral entry site located just proximal to the physis, at the junction of the posterior and lateral femoral cortices. The pin is inserted in the posterior-to-anterior direction at an angle of about 30° to the guidewire, parallel to the physis. As with the first guide pin, the pin is made to exit the ring opposite its entry site (Fig. 7). The guidewire and ring are then removed (Fig. 8). This allows verification that the guide pins are properly positioned relative to the physis (Fig. 9). Two cannulated screws 6.5 mm in diameter and measuring a few millimetres less in length than the width of the bone are inserted onto the guide pins (Fig. 10).

Two small medial incisions are made over the guide pin exit sites.

A braided steel cable measuring 18 mm is threaded in the medial-to-lateral direction through the proximal screw as the guide pin is being removed. The cable is recovered externally, passed under the soft tissues, and threaded in the lateral-to-medial direction through the distal screw. Finally, the cable is passed through the medial soft tissues then locked on itself with a torque force of 100 Nm (Fig. 11 and12). The knee is manipulated to release any adhesions.

Full weight bearing is resumed immediately after the procedure and physical therapy is provided to ensure early mobilisation.

Results and Discussion

The patients were included prospectively starting in August 2015. In all, 20 knees in 11 patients were studied. The rotational malalignment was idiopathic in 60% of cases and due to neuromuscular disease in 40% of cases. The families were informed in great detail of the advantages and drawbacks of the technique and provided their informed consent to the procedure.

Mean age at surgery was 10.1 years (range, 8.6-12.7 years). Mean time to screw removal was 21.5 months. In practice, the screws were removed as soon as the malalignment was corrected or the screw angle fell below 15°.

At the end of the treatment period, the mean values of all the clinical and radiological parameters were significantly improved, with p values below 0.0005. Thus, external hip rotation increased by 23°, internal hip rotation decreased by 31°, radiological femoral anteversion decreased by 28°, and the angle between the screws decreased by 25.4° (example in Fig. 12). These data confirm the efficacy of the technique, with a mean derotation of 1.2° per month.

The mean change in the distance between the two screws was 12 mm, versus a theoretical variation of 22 mm, suggesting a loss of length of about 12 mm over 2 years. Thus, part of the linear growth was converted to rotational growth (examples in Fig. 13).

The main post-operative complication was knee stiffness, which occurred in nearly all the cases, probably due to the presence of the cable. Cautious gentle manipulation under general anaesthesia was performed on 6 knees. For the 14 other knees, physical therapy was sufficient to gradually restore full range of motion. Mild recurvatum deformity of less than 10°, with no clinical consequences, developed in 8 knees, probably due to excessively anterior positioning of the screws. This complication occurred mainly in the first patients, who were treated before the technique was fully standardised. The patients in whom the procedure was performed bilaterally had no coronal malalignment or limb length discrepancy.

Conclusion

Guided growth protects the patient from the risks associated with osteotomy and internal fixation. This simple percutaneous technique is effective and allows immediate full weight bearing with no immobilisation. Knee stiffness is the main complication but resolves with time. This technique may therefore constitute an alternative to femoral derotation osteotomy if the outcomes reported here are confirmed in a larger number of patients with longer followup times.

Disclosure of interest

None of the authors has any conflicts of interest to disclose.

Funding

None

Contributions of each author

JDM wrote the manuscript.

LD collected the data. DD collected the data, performed the statistical analysis, and prepared the manuscript.

Figure 1 :

 1 Figure 1: As shown on this sawbone, physeal growth necessarily results in rotation.

Figure 2 :

 2 Figure 2: Left knee, intra-operative photograph of lateral guidewire insertion

Figure 3 :Figure 4 :Figure 5 :Figure 6 :

 3456 Figure 3: Lateral fluoroscopic view of the guidewire

Figure 7 :Figure 8 :

 78 Figure 7: Intra-operative photograph of the two percutaneously inserted guidepins and of the

Figure 9 :Figure 10 :Figure 11 :Figure 12 :Figure 13 :

 910111213 Figure 9: Fluoroscopy view to check proper guide pin position

Figure 1 :

 1 Figure 1 : exemple à gauche sur un sawbone : si la physe veut grandir la rotation est obligatoire

Figure 2 :

 2 Figure 2 : genou gauche, repérage de profil : vue clinique

Figure 3 :

 3 Figure 3 : repérage de profil : vue sur l'amplificateur de brillance

Figure 4 :

 4 Figure 4 : centrage de face : vue clinique

Figure 5 :

 5 Figure 5 : centrage de face : vue sur l'amplificateur de brillance

Figure 6 :

 6 Figure 6 : coupe axiale montrant la position théorique idéale des broches

Figure 7 :

 7 Figure 7 : broches en place avec l'anneau

Figure 8 :

 8 Figure 8 : broches en place sans l'anneau

Figure 9 :

 9 Figure 9 : vérification de la bonne position des broches

Figure 10 :Figure 12 :Figure 14 :

 101214 Figure 10 : mise en place des vis


Mickaël Artuso
email: mickael.artuso@gmail.com

Virginie Mas

Brice Ilharreborde

Keyvan Mazda

Pascal Jehanno

External Fixation: Role in Decreasing Post-Operative Complications of Complex Syndactyly Release -A Review of 18 Patients

Keywords: IV, retrospective observational study Complex syndactyly, Dressing, External Fixator, Post-Operative Care

Background: Primary and revision surgery for complete complex congenital syndactyly (CCCS) of the hand carries a risk of complications such as web maceration, which can result in flap or graft loss and alter the final appearance. No consensus emerges from the scant published data on post-operative care after CCCS surgery. The objective of this study was to assess the role for temporary external fixation in stabilising the commissure and facilitating surgical wound care.

Hypothesis: Using external fixation after CCCS release facilitates post-operative wound care and decreases the complication rate.

Material and Methods: 18 patients requiring primary CCCS surgery or revision CCCS surgery due to adhesions or web creep were included in a single-centre retrospective study.

After release, an external fixator made of Kirschner pins was installed to temporarily immobilise the inter-phalangeal joints. The dressing was changed every 3 days for 3 weeks, and the external fixator was then removed. The parents and nurses completed questionnaires that used 0-10 point scales to assess ease and duration of dressing changes and perceptions and apprehensions experienced by parents and nurses, as well as pain by patients, during dressing changes.

Results:

No patient experienced maceration or failure of a graft or flap. Pin site discharge was noted in 1 patient and resolved fully after pin removal. Pain intensity was estimated at 4.2/10 during the first dressing change and 1.3/10 during the last dressing change. In the parents, apprehension was 9.6/10 and 5.1/10 during the first and last dressing changes, and stress was 8.1/10 and 4.1/10, respectively. Dressing change difficulty was rated 1.1/10 at the first and 0.9/10 at the last dressing change. Dressing change duration decreased from 13 to 10 minutes.

Conclusion:

These encouraging results support temporary commissure stabilisation by an external fixator to decrease post-operative complication rates and facilitate dressing changes after CCCS release.

Introduction

Complete complex congenital syndactyly (CCCS) is defined as fusion of two or more fingers along their full length with more or less extensive nailfold and/or bone fusion. [START_REF] Kay | Deformities of the Hand and Fingers, Syndactylies, Green's Operative Hand Surgery[END_REF][START_REF] Abid | Malformations congénitales de la main[END_REF][START_REF] Swanson | A classification for congenital malformations of the hand[END_REF][START_REF] Swanson | A classification for congenital limb malformations[END_REF] Primary and revision surgery carries a high complication rate of 5.2% to 25%. [START_REF] Mcquillan | Incidence of acute complications following surgery for syndactyly and polydactyly: An analysis of the National Surgical Quality Improvement Program database from 2012 to 2014[END_REF][6][START_REF] Barabás | Results of syndactyly release using a modification of the Flatt technique[END_REF] Postoperative complications consist of maceration, web creep, surgical-site infection, and local flap or skin graft necrosis.

The surgical management of syndactyly is well standardised [START_REF] Dautel | Malformations congénitales des doigts longs[END_REF][START_REF] Braun | Syndactyly release[END_REF][START_REF] Samson | Syndactyly[END_REF][START_REF] Withey | The open finger technique for the release of syndactyly[END_REF][START_REF] Mallet | Comparative study of 2 commissural dorsal flap techniques for the treatment of congenital syndactyly[END_REF][START_REF] Yildirim | Correction of syndactyly using a dorsal separated V-Y advancement flap and a volar triangular flap in adults[END_REF] in terms of incision design and use of skin grafts and local flaps. In contrast, regarding post-operative care, no consensus emerges from the scant published data. [START_REF] Dautel | Malformations congénitales des doigts longs[END_REF][START_REF] Braun | Syndactyly release[END_REF][START_REF] Mallet | Comparative study of 2 commissural dorsal flap techniques for the treatment of congenital syndactyly[END_REF][START_REF] Chevaleraud | Anaesthesia for hand surgery in patients with bullous epidermolysis[END_REF][START_REF] Kamath | A novel method of using mini external fixator for maintaining web space after the release of contracture and syndactyly[END_REF] We hypothesised that temporary external fixation of the digits and commissures might prove beneficial.

The objective of this study was to assess the role for temporary external fixation in stabilising the commissure and facilitating surgical wound care. The working hypothesis was that external fixation after CCCS release facilitates post-operative care and decreases the complication rate.

Material and Methods

Study patients

This single-centre retrospective study included 18 patients (10 boys and 8 girls) who underwent CCCS surgery between January 2016 and October 2017. Among them, 14 had a single CCCS and 4 had two CCCSs each, for a total of 22 CCCSs. Mean age at surgery was 14 months (range, 6-36 months; median, 12.5 months) and mean follow-up was 13.3 weeks (range, 3-41 weeks; median, 10.5 weeks). Primary surgery was performed in 13 patients and revision surgery in 5 patients. The reason for revision surgery was local maceration with skin graft and/or local flap loss in 3 patients and web creep in 2 patients. We did not study patients with simple or incomplete syndactyly, which are associated with lower post-operative complication rates and do not routinely require skin grafting.

Of the 18 patients, 8 patients had genetic multiple malformation syndromes, including 5 with Apert syndrome and 3 with Poland syndrome. These 8 patients and another patient had severe bone abnormalities including hypoplasia of the hand, delta phalanx, missing phalanx, and extensive synostosis.

Informed consent to use of an external fixator was obtained from the parents before surgery. The parents were given information on the appearance and size of the external fixator, with photographs, and on the post-operative care and follow-up modalities.

In each patient, the surgeon performed a clinical and radiological evaluation of the hands. Patients with multiple malformations were evaluated by a multidisciplinary team. All patients received follow-up from the same surgeon. Wound care was given by surgical nurses at the hospital outpatient clinic.

Surgery and post-operative care

Syndactyly release was achieved by Cronin zigzag incisions with creation of a dorsal commissural omega flap. [START_REF] Mallet | Comparative study of 2 commissural dorsal flap techniques for the treatment of congenital syndactyly[END_REF] A Buck-Gramcko [START_REF] Buck-Gramcko | Congenital malformations: syndactyly and related deformities[END_REF][START_REF] Golash | Nail fold creation in complete syndactyly using Buck-Gramcko pulp flaps[END_REF] flap was used when nailfold reconstruction was required. A full-thickness skin graft was harvested from the anterior aspect of the wrist or, more rarely, the groin. Surgery was performed with a tourniquet applied to the arm and inflated to twice the patient's systolic blood pressure; the tourniquet was released before graft implantation and wound dressing.

Once release was achieved, the proximal and distal inter-phalangeal joints of the two fingers involved were immobilised using 10/10 th Kirschner pins inserted using a Jacobs chuck. The pins were bent and connected to each other to spread and immobilise the fingers (Figures 1 and2). The dressing was fashioned at the end of the procedure by applying an antiadhesive silicone interface followed by gauze pads and, finally, by a crepe bandage. No radiographs were taken at this point. Analgesics consisted of ibuprofen and paracetamol in dosages adjusted for body weight, for 3 days and 21 days, respectively

The dressings were changed at the hospital outpatient clinic twice a week, in the presence of the parents, for 3 to 4 weeks depending on the pace of wound healing. The surgeon re-evaluated each patient once a week. The dressings were changed by the outpatient nurses, who had not received specific training for this type of wound care and were instructed to follow prescriptions for wound care supplies (which were identical to those used in the operating room). The patients were to take the analgesics 1 hour before the dressing change.

The surgeon used forceps to remove the pins 21 days after the surgical procedure.

Once the wound was healed, the parents were to apply a moisturising cream (glycerol, paraffin, and petroleum jelly) to the hands for 2 weeks. Rehabilitation was via spontaneous activity, stimulated if needed by playing. The patients were re-evaluated every 2 months.

Study data collection

The study data were collected by having the parents and nurses complete selfadministered questionnaires at each dressing change (Figure 3). The items were developed with the hospital psychologist and rated on a scale of 0 to 10. Pain experienced by the patients during the dressing changes was assessed by the nurse using the FLACC Pain Assessment Tool [START_REF] Merkel | The FLACC: a behavioral scale for scoring postoperative pain in young children[END_REF] (Table 1).

At each dressing change, the wounds were examined for local maceration or infection and for necrosis of a flap or graft, which were recorded.

Results

The total number of dressing changes was 113, yielding a mean of 6.3 per patient.

Mean time needed to change the dressing was 13 minutes (range, 10-16 minutes for the first dressings and 10 minutes (range, 7-13) for the last dressings. No patient was lost to follow-up.

No patient experienced maceration or failure of a local flap or graft.

A single patient experienced a complication, consisting in a skin reaction (erythema and clear discharge) 16 days post-operatively at a pin entry site. The symptoms resolved fully after pin removal, without antibiotic therapy.

Table 2 reports the data on pain intensity as assessed using the FLACC tool. Mean pain intensity was 4.2/10 for the first dressing and diminished thereafter to 1.3/10 for the last dressing. No patient required equimolar oxygen/nitrous oxide during the dressing changes.

The data on the other questionnaire items also show marked improvements from the first to the last dressing change (Table 2).

Discussion

The use of external fixation in the study patients was effective in preventing postoperative complications, confirming the working hypothesis.

Wound care is a key component of the post-operative programme for patients with complete congenital syndactyly, notably those with complex forms, in whom the complication rate exceeds 5%. However, few published studies have described wound care after CCCS release. [START_REF] Dautel | Malformations congénitales des doigts longs[END_REF][START_REF] Braun | Syndactyly release[END_REF][START_REF] Mallet | Comparative study of 2 commissural dorsal flap techniques for the treatment of congenital syndactyly[END_REF][START_REF] Chevaleraud | Anaesthesia for hand surgery in patients with bullous epidermolysis[END_REF][START_REF] Kamath | A novel method of using mini external fixator for maintaining web space after the release of contracture and syndactyly[END_REF] We initially reserved external fixation for patients undergoing revision CCCS surgery.

These patients already had experience with conventional post-operative wound care. The outcomes were favourable and the parents reported marked improvements in early post-operative care and levels of pain during dressing changes compared to the primary procedure.

We therefore decided to use external fixation routinely after CCCS surgery.

Our decision to reserve external fixation for patients with CCCS (including patients with multiple malformation syndromes) was based on the complication rates reported by

McQuillan [START_REF] Mcquillan | Incidence of acute complications following surgery for syndactyly and polydactyly: An analysis of the National Surgical Quality Improvement Program database from 2012 to 2014[END_REF] (5.2% in patients with CCCS vs. 2.3% in those with simple syndactyly within 30 days after surgery), Bulic [6] (12%), and Barabas and Pickford [START_REF] Barabás | Results of syndactyly release using a modification of the Flatt technique[END_REF] (25%). In patients with multiple malformation syndromes, CCCS is often associated with severe bone malformations that require extensive skin grafting and complex local flaps. External fixation was therefore warranted to ensure optimal graft and flap survival by improving wound aeration and by decreasing maceration and shear forces.

The dressings were changed twice a week in our study. Criticism has been directed at frequent dressing changes, albeit without any supporting evidence. [START_REF] Dautel | Malformations congénitales des doigts longs[END_REF][START_REF] Braun | Syndactyly release[END_REF][START_REF] Mallet | Comparative study of 2 commissural dorsal flap techniques for the treatment of congenital syndactyly[END_REF][START_REF] Chevaleraud | Anaesthesia for hand surgery in patients with bullous epidermolysis[END_REF][START_REF] Kamath | A novel method of using mini external fixator for maintaining web space after the release of contracture and syndactyly[END_REF] The high rate of maceration seen when the dressing is not changed, or when casting is used for immobilisation, warrants frequent dressing changes. The specific histological characteristics of the paediatric skin, [START_REF] Leung | Biology and function of fetal and pediatric skin[END_REF] including greater exudation and sweating and a higher pH compared to adult skin, require wound care at shorter intervals. We recognise, however, that the need to go to the hospital twice a week for dressing changes places a burden on the families, and we believe that changing the dressing once a week would have no adverse impact on the surgical outcomes. Furthermore, we feel that community nurses could provide the wound care needed after CCCS release, after receiving limited training consisting simply in providing the parents with a written document describing the procedure.

The questionnaire data showed that the anticipatory anxiety experienced by the parents decreased from one dressing change to the next. The nurses described the technical aspects of the procedure as simpler and faster. The data on pain intensity obtained using the FLACC tool established that the use of an external fixator contributed to diminish the level of pain.

None of the patients experienced maceration, web creep, graft loss, or flap necrosis, and none required revision surgery.

This work was a pilot study in a small number of patients. Consequently, no statistically significant differences can be demonstrated.

External fixation has been used previously after syndactyly release in patients with epidermolysis bullosa (Chevaleraud et al. [START_REF] Chevaleraud | Anaesthesia for hand surgery in patients with bullous epidermolysis[END_REF] ) or burn scars (Kamath et al. [START_REF] Kamath | A novel method of using mini external fixator for maintaining web space after the release of contracture and syndactyly[END_REF] ). The external fixators were bulkier than the ones used in our patients. Both study reports describe decreased maceration rates and virtually no infections, although no numerical data are provided. The external fixator described here is used only in paediatric patients and is smaller and readily accepted by the families. Our study is the first to provide numerical data on outcomes after using external fixation for post-operative CCCS care.

It has been suggested that the dressing should not be changed for the first 2 to 3 weeks. [START_REF] Dautel | Malformations congénitales des doigts longs[END_REF][START_REF] Braun | Syndactyly release[END_REF] The dressing is made of a silicone interface overlain with woven gauze pads and, in some cases, by a protective cotton layer reinforced by cast immobilisation. The studies report no clinical or numerical data and did not select specific types of syndactyly. In paediatric patients, irrespective of whether cast immobilisation is used, leaving a dressing unchanged for 3 weeks carries a high risk of maceration and may result in delayed wound healing or even in local infection or failure of the procedure requiring revision surgery. On the other hand, changing the dressing too often may result in shear forces being applied when the child moves, potentially causing a flap or skin graft to detach.

Post-operative care after CCCS release requires specific precautions. External fixation can facilitate this phase of patient management.

Conclusion

The data reported here support the use of external fixation after CCCS release as a means of decreasing pain intensity, facilitating wound care, and preventing post-operative complications. External fixation prevents maceration by spreading the fingers and prevents complications such as graft loss, flap necrosis, and web creep. We reserve external fixation for selected patients. However, we believe that external fixation should be considered when the risk of post-operative complications is high. Further studies are needed to assess long-term outcomes.

Disclosure of interest

None of the authors has any conflicts of interest to declare. For the parents 1)On a scale of 0 to 10, grade your degree of apprehension before the procedure was performed (fear that the procedure would cause pain to your child) (0: none; 10, severe)

2)Describe your perception and experience of the procedure in terms of stress, on a scale from 0 to 10 (0: none; 10, severe)

For the nurses 1)On a scale of 0 to 10, grade your degree of apprehension before performing the procedure (0: none; 10, severe)

2)On a scale of 0 to 10, grade the difficulty encountered in performing the procedure (0, very easy to perform; 10, very technically demanding).

3)Record the time from entry to exit of the patient, in minutes.

Figure 1 :Figure 2 :

 12 Figure 1: Release of the third web space in a patient with Apert syndrome

Figure 3

 3 Figure 3: Questionnaire.

Table 1 :

 1 The FLACC Pain Assessment Tool

	FACE	0 No particular expression or smile
		1 Occasional grimace of frown, withdrawn, disinterested
		2 Frequent to constant frowning, clenched jaw, quivering chin,
	LEGS	0 Normal position or relaxed
		1 Uneasy, restless, tense
		2 Kicking or legs drawn up
	ACTIVITY	0 Lying quietly, normal position, moves easily
		1 Squirming, shifting, back and forth, tense
		2 Arched, rigid, or jerking
	CRY	0 No cry (awake or asleep)
		1 Moans or whimpers, occasional complaint
		2 Crying steadily, screams, sobs, frequent complaints
	CONSOLABILITY 0 Content, relaxed
		1 Reassured occasionally by touching, hugging, or being talked to,
		distractible
		2 Difficult to console or comfort

Table 2 :

 2 Results of the questionnaires and FLACC scale

		First dressing changes	Last dressing changes
		Mean	Range	Mean	Range
	Pain	4.2/10	1-7	1.3/10	0-3
	Anticipatory anxiety experienced by the parents	9.6/10	9-10	5.1/10	3-6
	Perceptions reported by the parents	8.1/10	4-10	4.1/10	0-7
	Anticipatory stress experienced by the nurse	1.1/10	0-4	0.3/10	0-2
	Difficulty	1.1/10	0-3	0.9/10	0-2
	Procedure duration (minutes)	13	10-16	10.2	7-13

Funding

None


Yves Catonné
email: yves.catonne@gmail.com

Elhadi Sariali

Frédéric Khiami

Jean-Louis Rouvillain

Antony Wajsfisz

Hugues Pascal-Moussellard

Same-Stage Total Knee Arthroplasty and Osteotomy for Osteoarthritis with Extra-Articular Deformity. Part I: Tibial Osteotomy, Prospective Study of 26 Cases

Keywords: Knee osteoarthritis, Extra-articular knee deformities, Same-stage total knee arthroplasty and proximal tibial osteotomy

de documents scientifiques de niveau recherche, publiés ou non, émanant des établissements d'enseignement et de recherche français ou étrangers, des laboratoires publics ou privés.

International Knee Society (IKS score) was assessed and the hip-knee-ankle angle (HKA), tibial mechanical angle (TMA), and femoral mechanical angle (FMA) were measured on radiographs before surgery and at last follow-up.

Results:

The mean IKS score increased significantly, from 70 before surgery to 170 at the end of the mean 9-year follow-up. Mean flexion range increased from 98° to 107°. The clinical and anatomical outcomes were satisfactory in 25 patients. In the remaining patient, who had a history of multiple surgeries for Blount disease and a body mass index of 49, a severe complication consisting in massive skin necrosis followed by infection occurred; this was the only patient who required revision surgery with implant removal.

Discussion: These findings are consistent with the satisfactory outcomes observed in earlier studies, most of which included small numbers of patients. The alternatives to 1S-TKA-TO

Introduction

Advanced knee osteoarthritis may be accompanied with severe extra-articular knee deformity (EKD) involving either the femur or the tibia. EKDs are often mild and amenable to correction during total knee arthroplasty (TKA) by adjusting the bone cut to balance the ligaments and release the concave side of the joint. With severe EKD, in contrast, correction via the usual bone cuts requires extensive resection on the convex side, which may induce laxity or exacerbate pre-existing laxity. EKD correction at its extra-articular site of occurrence, by performing a tibial osteotomy (TO), deserves consideration in this situation. In patients with osteoarthritis involving all three knee compartments, as well as in elderly individuals, EKD correction can be combined with TKA, in one or two stages. In 1991, Wolff and Hungerford (1) reported the first case of same-stage TKA and TO (1S-TKA-TO) and highlighted the limitations of intra-articular EKD correction. Anecdotal case-reports and small case-series were published subsequently [START_REF] Chilling | Combined osteotomy and total knee replacement for angular deformities associated with advanced osteoarthritis[END_REF][START_REF] Uchinou | A severely overcorrected high tibial osteotomy. Revision by osteotomy and a long stem component[END_REF][START_REF] Zanone | Prothèse totale et ostéotomie tibiale de correction simultanées pour gonarthrose sur genu varum excessif constitutionnel[END_REF][START_REF] Scott | Tibial osteotomy coincident with long stem total knee arthroplasty A surgical technique[END_REF]. In 2002, Radke (6) reported good clinical outcomes and a low morbidity rate in 10 patients managed by 1S-TKA-TO.

The objective of this study was to assess clinical and anatomical outcomes, as well as morbidity, in 26 patients managed with 1S-TKA-TO. The working hypothesis was that 1S-TKA-TO produces satisfactory clinical and anatomical outcomes and is not associated with higher morbidity rates compared to TKA alone or two-stage TKA-TO.

Material and Methods

Material

Between 1995 and 2014, 26 1S-TKA-TO procedures were performed in 25 patients who were followed-up for at least 3 years (Table 1). The EKDs were classified using a simplified variant of the Hungerford and Krackow classification [START_REF] Hungerford | Management of fixed deformity at total knee arthroplasty[END_REF], as follows (8): Type 1, isolated wear; Type 2, wear and laxity; Type 3, wear and intra-osseous deformity; and Type 4, wear, intra-osseous deformity, and laxity. All 26 knees had Type 3 deformity with greater than 10° of intra-osseous angulation. Of the 26 procedures, 24 were performed by the same surgeon (YC) working successively in three different centres.

There were 16 males and 9 females with a mean age at surgery of 64 years (range, 29-80 years) and a mean body mass index of 29.6 (range, 24-49). In the Ahlbäck classification of knee osteoarthritis, 5 knees were grade 2, 13 knees were grade 3, and 8 knees were grade 4.

The intra-osseous EKD consisted in an at least 10° angulation in the coronal plane in 23 knees. There was 1 case each of combined valgus and recurvatum, sagittal EKD with a 30° tibial slope, and proximal tibial mal-union with major translation. Malalignment in the coronal plane was noted in 24 knees, in which the mean hip-knee-ankle angle (HKA) was 158° (range, 150°-166°) for the subgroup with pre-operative varus and 197° (range, 191°-210°) for the subgroup with pre-operative valgus. The EKD was constitutional in 14 knees; in the remaining 12 knees, the cause was mal-union due to trauma (n=5) or osteotomy (n=7). Of the 14 constitutional EKDs, 10 were varus deformities, including 1 due to Blount disease and 1 due to multiple epiphyseal dysplasia; the remaining 4 were in valgus.

The same operative technique was applied for all 26 knees. The first step was implantation of the femoral component. TO was then performed and fixed temporarily using staples. A long-stemmed tibial implant was then inserted after reaming using a rigid reamer to allow a tibial cut perpendicular to the tibial axis. The type of osteotomy varied with the type of EKD: an opening wedge TO was performed for the 13 knees with tibial varus, a closing wedge TO for the 10 knees with tibial valgus (Figures 1 and2), an anterior closing wedge TO after anterior tibial tuberosity section in a knee with intra-osseous flexion deformity (knee #1), varus and flexion TO in a patient with both tibial valgus and recurvatum (Figure 3), and lateral translation TO after anterior tibial tuberosity elevation in a patient with translation due to mal-union (Figure 4).

Tibial fixation was performed for 21 knees. A long-stemmed tibial implant was used in all but 1 case (knee #1); stem length was usually 10 cm (15 cm for 6 knees) and the stem was either straight (n=14) or offset (n=11).

The degree of constraint was determined pre-operatively. For 23 knees, a posteriorstabilised implant with a fixed tibial plateau was used. The 3 remaining knees were replaced with a posterior-stabilised condylar knee implant featuring an extended cam (CCK type). No hinged implants were used.

Post-operative care consistently included weight bearing starting on the first postoperative day and early joint mobilisation. An extension splint was worn during walking for the first 45 days.

Methods

Clinical and radiographic parameters were recorded before and after surgery. The For each patient, intra-operative, immediate post-operative, and delayed post-operative complications were recorded, as well as any revision procedures. The patients attended follow-up visits 45 days, 6 months, 1 year, 2 years, and 5 years after surgery then once every 5 years.

Statistical analysis

Variable distribution was tested for normality by applying the Ryan-Joiner and Shapiro-Wilk tests. Normally distributed variables between two groups with similar variances were compared by applying Student's t test. For non-normally distributed variables and for variables whose variances differed between groups, the non-parametric Mann-Whitney test was used. Values of p smaller than 0.05 were taken to indicate significant differences.

Results

For 24 patients (25 knees), follow-up ranged from 3 to 18 years, with a mean of 9 years (Table 2). The remaining patient died of heart failure 1 year after surgery.

Clinical outcomes

The mean total IKS score increased from 70 (range, 29-104) pre-operatively to 170 (range, 126-190) post-operatively, yielding a significant mean increase of 98.9±17.6 (p<0.0001). The IKS knee score increased from 28.5 (range, 10-59) before surgery to 84 (range, 56-99) after surgery. Range of flexion increased from 98° (range, 5°-120°) before surgery to 107° (range, 0°-130°) after surgery, yielding a significant mean increase of 16.3°±8.3°.

Radiological outcomes

After surgery, the HKA was 180°±3° for 24 knees. The remaining 2 knees had HKA values of 175° and 184°, respectively Before surgery, the mean FMA was 90.5° (range, 82°-93°). Marked femoral varus (82°)

in the patient with multiple epiphyseal dysplasia resulted in post-operative varus (HKA, 175°).

For the 13 knees with varus deformity, the mean TMA was 74° (range, 67°-79°) before surgery and 89° (range, 87°-92°) after surgery. Corresponding values for the 11 knees with valgus deformity were 105° (range, 100°-118°) and 89.7° (range, 87°-94°), respectively.

Complications and revision procedures

The only intra-operative complication was a secondary tibial fracture line, which occurred in 4 patients but had no influence on the final outcome.

A single patient (#24) experienced a severe post-operative complication. This 40-yearold male with morbid obesity (BMI, 49) and a history of three surgical procedures on the same knee in childhood to treat Blount disease had major functional impairment, marked knee stiffness (flexion range, 60° with 15° of fixed flexion deformity), and a severe EKD (TMA, 69°). TKA with opening-wedge valgus TO was performed. Extensive skin necrosis developed and was managed by a medial gastrocnemius flap. However, the site became infected, requiring implant removal followed by knee fusion. Despite this severe complication and the permanent loss of knee mobility, a substantial clinical improvement was obtained (IKS score, 50 before and 126 after surgery).

Six other post-operative complications were recorded: deep vein thrombosis in 2 cases, haematoma in 2 cases including 1 that requiring drainage, extensor hallucis deficiency that resolved within 1 year, and a 15° extension lag that persisted at last follow-up (patient #5). No patient experienced secondary displacement, loosening, or non-union. In 1 patient, the staples protruded under the skin and were therefore removed.

4.

Discussion

1 Results

The results confirm the working hypothesis. The mean flexion range of 107° after 1S-TKA-TO was more limited than in case-series studies of patients with usual forms of knee osteoarthritis but was comparable to values in patients with marked EKDs and post-traumatic osteoarthritis [START_REF] Parratte | French Hip and Knee Society). Total knee replacement following intra-articular malunion[END_REF]. The smaller pre-operative flexion range (mean, 98°) compared to studies of standard TKA procedures is worth noting. Flexion range was particularly limited in the subgroup of 5 patients with post-traumatic EKD (mean, 77°), in whom the mean flexion gain was 28°, versus 9° in the overall population.

The good overall alignment (HKA and TMA values) after surgery may be related to the use of a long-stemmed implant that necessarily produced alignment on the reaming guide then on the stem after the osteotomy.

Comparison with earlier data

Operative technique

An uncemented long stem was used on the side of the osteotomy in 25 knees in our study (the exception being knee #1). The TO was consistently performed before implantation of the tibial component. Several other techniques have been described. Lerat et al. [START_REF] Lerat | Prothèse totale de genou associée à une désostéotomie : technique de l'ostéotomie après la mise en place de la prothèse[END_REF] used a tibial implant with either a short stem or anchoring pegs, which they inserted before performing the TO under the tibial implant, during the same stage. The clinical outcomes were good in 8 patients managed by TO reversal, although 1 patient required grafting to treat non-union and the mean time to healing was 5 months (10). Vielpeau et al. [START_REF] Vielpeau | Ostéotomie tibiale et prothèse totale de genou simultanées[END_REF] described TO via a lateral approach after eversion of the anterior tibial tuberosity. Fixation was ensured by an intramedullary extension rod. The clinical outcomes were good, despite early construct disassembly in 1 of the 14 patients. The authors stated that this technique should be reserved for EKDs greater than 8°.

Other treatment options for extra-articular knee deformities (EKDs)

Most authors use cuts at a 90° angle combined with soft-tissue release on the concave side [START_REF] Teeny | Primary total knee arthroplasty in patients with severe varus deformity[END_REF][START_REF] Deschamps | Total knee arthroplasty for osteoarthritis secondary to extra articular malunions[END_REF]. It has been suggested that this technique is always feasible [START_REF] Koenig | Extra-articular deformity is always correctable intra-articularly: in the affirmative[END_REF]. In some cases, however, an osteotomy must be performed, either before or concomitantly with TKA (Figures 3 and4). Release of the concave side is often feasible but has limitations that vary with the site and severity of the deformity [START_REF] Wolff | The effect of extraarticular varus and valgus deformity on total knee arthroplasty[END_REF]. Rather than overall lower limb malalignment (as assessed by the HKA), emphasis should be put on the tibial deformities (TMA). There is general agreement that release is not appropriate when the TMA is below 80° or above 100°.

Comparisons with the literature

The outcomes in our study cannot be readily compared to those obtained using hinged implants or TKA with extensive release, as few studies report long-term TKA outcomes in patients with severe EKDs. In addition, the available short-term studies provide little information on post-operative laxity [START_REF] Wang | Total Knee Arthroplasty for arthritis of the knee with extra-articular deformity[END_REF].

Similarly, although many studies have investigated the outcomes of TKA performed after TO, none focussed exclusively on patients with severe EKDs in whom TKA was performed as the second stage. Nevertheless, primary osteotomy seems reasonable in patients younger than 65 years of age, as it may substantially delay the need for TKA. When TKA is necessary due to major functional impairment with involvement of all three knee compartments, multi-stage surgery with primary osteotomy, a waiting period until healing is achieved, removal of the fixation material if needed, and finally TKA requires considerable time and is often poorly accepted by patients (6).

Complications

The occurrence in one of our patients of a severe complication that required joint fusion surgery illustrates the risks potentially associated with combined TKA and osteotomy.

Revision surgery with implant exchange was not required in any of the other patients during the mean follow-up of 9 years. More specifically, no patient experienced treatment failure due to residual laxity.

Conclusion

1S-TO-TKA is a satisfactory option in patients with advanced knee osteoarthritis and severe EKD (overall deformity usually >20° and intra-osseous deformity ≥10°). This procedure avoids the laxity on the convex side seen when a 90° tibial cut is performed at the site of an intra-osseous deformity.

The use of a semi-constrained long-stemmed knee prosthesis ensures proper tibial alignment, bone healing within a reasonable timeframe, and satisfactory clinical outcomes.

  clinical parameters included the body mass index (BMI), range of knee flexion and extension, and the International Knee Society (IKS) knee and function scores. Laxity in varus and valgus was sought. The radiographic parameters were measured on antero-posterior and lateral single-leg weight-bearing views, an antero-posterior schuss view, a 30° skyline view, and a long-leg view; starting in 2010, the long-leg view was replaced by EOS imaging. Computed tomography was performed for knees with rotational malalignment or post-traumatic malunion. The following radiological parameters were measured: HKA, formed by the mechanical axes of the femur and tibia; femoral mechanical angle (FMA) on the medial side of the intersection between the mechanical axis of the femur and the bicondylar line, to assess the femoral intra-osseous EKD, with values of 90° to 94° classified as normal; and tibial mechanical angle (TMA) subtended by the mechanical axis of the tibia and the line tangent to the normal plateau, to assess the tibial intra-osseous EKD, with values of 86° to 90° classified as normal.

Figure 1 a:Figure 2 a:Figure 3 a:Figure 4 a:

 1234 FIGURE LEGENDS

Table 2 :

 2 Type of procedure and pre-and post-operative data in the study population HKA, hip-knee-ankle angle; TMA, tibial mechanical angle; FMA, femoral mechanical angle; ROM, range of motion; IKS, International Knee Score; FU, follow-up; ant, anterior; post, posterior; med, medial; CWO, closing-wedge osteotomy; OWO, opening-wedge osteotomy; trans, translation; PS, posterior-stabilised; CCK, Constrained Condylar Knee (posteriorstabilised extended cam)

	Technique Fixation	Constraint	Year of surgery	HKA op. pre-	HKA op post-	TMA op. pre-	FMA op. pre-	TMA op post-	ROM op. pre-	ROM op post-	IKS op. pre-	IKS op post-	Complications Revision	Year FU of last	FU, y
																		di
	Ant CWO screw	PS stem	1995	182	181	88°	92°	91	110°	100°	70	178	none	no	2001	7	in
																		20
	Ant OWO staple	PS stem	1997	159	179	77°	91°	89	110°	115°	45	175	deep vein thrombosis	no	2015	18	di in 20
	Ant OWO plate	PS stem	1999	159	179	67°	92°	90	120°	120°	78	180	none	no	2013	14
																		di
	Ant OWO plate	PS stem	1999	158	181	78°	91°	90°	90°	100°	68	130	none	no	2000	1	in
																		20
	Med CWO	none	PS stem	1999	210	184	118°	92°	94°°	90°	110°	33	147	secondary fracture line	no	2010	11	di in 20
	Ant OWO plate	PS stem	2000	158	179	75°	86°	89°	90°	100°	61	145	none	no	2015	15
	Ant OWO none	PS stem	2000	150	181	79°	86°	90°	100°	110°	88	180	none	no	2015	15
	Ant OWO none	PS stem	2001	158	179	75°	91°	89°	120°	120°	79	179	haematoma	drainage 2015	14
	Ant OWO staple	PS stem	2002	166	178	77°	92°	89°	110°	120°	77	179	none	no	2016	13
	Med and
	post CWO	staple	CCK	2003	192	175	100°	82°	88°	110°	120°	94	184	none	no	2017	14
	Med CWO	staple	PS stem	2006	196	182	102°	91°	91°	115°	120°	78	180	none	no	2017	11
																		di
	Ant OWO staple	PS stem	2007	158	178	79°	91°	89°	90°	90°	75	168	none	no	2012	5	in
																		20
	Med CWO	staple	PS stem	2007	197	182	101°	92°	91°	120°	120°	72	150	none	no	2016	9	di in 20
	Med CWO	staple	PS stem	2009	198	183	104°	92°	94°	110°	115°	65	155	none	no	2016	7	di in 20
	Ant OWO none	PS stem	2008	150	183	68°	92°	92°	100°	110°	55	183	none	no	2017	9
	Med CWO	staple	PS stem	2008	195	178	101°	92°	88°	120°	120°	54	155	none	no	2016	8
	Ant OWO staple	PS stem	2008	166	181	68°	91°	91°	120°	130°	82	178	none	no	2009	8
	Med CWO	staple	PS stem	2010	210	182	112°	92°	90°	100°	100°	68	180	none	no	2017	7
	Med CWO	staple	PS stem	2010	191	181	101	90°	90°	100°	120°	85	180	none	non	2018	8
	Med CWO	staples	PS stem	2011	191	178	101°	88°	89°	120°	120°	70	175	none	removal staple of a	2017	6
	Ant OWO plate	PS stem	2011	165	175	79°	91°	87°	100°	110°	104	190	none	no	2017	6
	Med CWO	staples	PS stem	2011	190	171	101°	92°	90°	120°	120°	89	189	none	no	2016	5
														haematoma,
	Ant OWO none	PS stem	2011	161	177	70°	90°	87°	105°	110°	73	185	secondary	no	2017	6
														fracture line
	Ant OWO plate	CCK	2012	155	179	69°	93°	88°	60°	0°	50	126	necrosis and infection	fusion	2018	6
														15° extension
	Med CWO	staples	LPS stem	2014	193	179	102°	91°	89°	120°	125°	80	173	lag secondary	no	2018	4
														fracture line
	trans.	staples	CCK	2014	186	182	96°	91°	89°	5°	85°	29	170	secondary fracture line	no	2017	3