Nawel Ouendi

Eugénie Avril

Benjamin Dervaux

Philippe Pudlo

Laura Wallard
email: laura.wallard@uphf.fr

Effectiveness of tele-rehabilitation programs in elderly with hip osteoarthritis: a scoping review

Keywords: Hip osteoarthritis, osteoarthritis, New information and communication technologies, e-health, tele-rehabilitation I

Background: Hip osteoarthritis generates very often musculoskeletal pain causing functional impairment and decreasing mobility, autonomy and quality of life. Patients are then often offered specific telerehabilitation care to provide them with the possibility to practice painless and supervised adapted physical and functional activities. But what about effectiveness of these telerehabilitation programs? Objectives: The aim of this scoping review is to list and highlight different telerehabilitation currently offered during hip OA care in order to assess their effectiveness in programs care. Methods: 5 databases were screened for "osteoarthritis", "hip osteoarthritis", "pre-operation", "rehabilitation", "tele-rehabilitation", "digital health", "telecommunication" in accordance with PRISMA-ScR guideline. Results: 19 articles were selected according to inclusion criteria. The telerehablitation was offered in 6 different ways (video call, applications smartphones, website, etc.). The assessments were mainly quality of life questionnaires, the perceived effort after exercises, field surveys on the tool experience, physical tests to assess motor functions and interviews to measure acceptability before use.

Conclusion:

This review highlights the importance and relevance to evaluate contributions and limitations of new healthcare technologies in order to improve patient follow-up and thus enable better remote clinical care.

INTRODUCTION

Osteoarthritis (OA) is the most common joint disease, affecting about 240 million people worldwide, including more than 10 million in France [START_REF] Katz | Diagnosis and treatment of hip and knee osteoarthritis: a review[END_REF], becoming a major public health problem [START_REF] Klussmann | Individual and occupational risk factors for knee osteoarthritis: results of a case-control study in Germany[END_REF]. According to INSERM (2022), 10% of cases in France are affected by coxarthrosis. Hip OA is characterised by a progressive degeneration of joint that affects cartilage, bone, and periarticular soft tissues [START_REF] Katz | Diagnosis and treatment of hip and knee osteoarthritis: a review[END_REF]. Several studies have showed that hip OA is characterised by severe musculoskeletal pain and limitation of articular movement gradually decreasing autonomy and quality of life of OA patients. Pain and stiffness directly impact mobility and the ability to be physically active [START_REF] Pua | Intrarater test-retest reliability of hip range of motion and hip muscle strength measurements in persons with hip osteoarthritis[END_REF][START_REF] Steultjens | Range of joint motion and disability in patients with osteoarthritis of the knee or hip[END_REF][START_REF] Winter | Walking ability during daily life in patients with osteoarthritis of the knee or the hip and lumbar spinal stenosis: a cross sectional study[END_REF]. Indeed, the hip OA impacts negatively the functional activity and the global mobility of the patient. For exemple, the gait is then illustrated by abnormal patterns [START_REF] Eitzen | Sagittal plane gait characteristics in hip osteoarthritis patients with mild to moderate symptoms compared to healthy controls: a cross-sectional study[END_REF][START_REF] Foucher | Sagittal plane hip motion reversals during walking are associated with disease severity and poorer function in subjects with hip osteoarthritis[END_REF][START_REF] Wallard | Does the quantitative functional assessment allow to better guide the treatment of the patient with severe hip osteoarthritis?[END_REF][START_REF] Wallard | Intersegmental kinematics coordination in unilateral peripheral and central origin: effect on gait mechanism?[END_REF] associated with a reduced walking speed [START_REF] Schepens | Fatigability in osteoarthritis: effects of an activity bout on subsequent symptoms and activity[END_REF][START_REF] Schmitt | Effect of end-stage hip, knee, and ankle osteoarthritis on walking mechanics[END_REF], a reduction of the hip muscle strength [START_REF] Eitzen | Sagittal plane gait characteristics in hip osteoarthritis patients with mild to moderate symptoms compared to healthy controls: a cross-sectional study[END_REF][START_REF] Constantinou | Spatial-temporal gait characteristics in individuals with hip osteoarthritis: a systematic literature review and meta-analysis[END_REF][START_REF] Foucher | Preoperative gait adaptations persist one year after surgery in clinically wellfunctioning total hip replacement patients[END_REF] and higher cardiac and energetic costs of gait [START_REF] Schepens | Fatigability in osteoarthritis: effects of an activity bout on subsequent symptoms and activity[END_REF][START_REF] Schmitt | Effect of end-stage hip, knee, and ankle osteoarthritis on walking mechanics[END_REF] relative to asymptomatic adults. (e.g. walking, climbing stairs) [START_REF] Pua | Intrarater test-retest reliability of hip range of motion and hip muscle strength measurements in persons with hip osteoarthritis[END_REF][START_REF] Wallard | Does the quantitative functional assessment allow to better guide the treatment of the patient with severe hip osteoarthritis?[END_REF][START_REF] Wallard | Intersegmental kinematics coordination in unilateral peripheral and central origin: effect on gait mechanism?[END_REF][START_REF] Schepens | Fatigability in osteoarthritis: effects of an activity bout on subsequent symptoms and activity[END_REF][START_REF] Schmitt | Effect of end-stage hip, knee, and ankle osteoarthritis on walking mechanics[END_REF]. Patients with hip OA are commonly prescribed exercise-based rehabilitation programs that focus on reducing pain and improving physical function [START_REF] Constantinou | Spatial-temporal gait characteristics in individuals with hip osteoarthritis: a systematic literature review and meta-analysis[END_REF][START_REF] Foucher | Preoperative gait adaptations persist one year after surgery in clinically wellfunctioning total hip replacement patients[END_REF][START_REF] Othman | NE Exercice pour l'arthrose des membres inférieurs : examen systématique incorporant une analyse séquentielle des essais et une méta-analyse en réseau[END_REF][START_REF] Allen | Osteoarthritis physical activity care pathway (OA-PCP): results of a feasibility trial[END_REF].

In recent years, and with the deployment of public health budget strategies, new information and communication technologies (NTIC) are increasingly used in the monitoringand clinical care of patients, especially in pre-and postoperative orthopaedic management. These new e-health devices are indeed proving to be a relevant solution for a distance care of people with reduced mobility [START_REF] Peretti | Telerehabilitation: review of the state-of-the-art and areas of application[END_REF]. Indeed, the term e-health, with its equivalents: telehealth, digital health, connected health, refers to all areas where TICs are used for health purposes [START_REF] Safon | La e-santé Télésanté, santé numérique ou santé connectée[END_REF]. General sense, digital health is defined as the use of digital information, data and communications to collect and analyse health information to improve patient care and health and the delivery of care [START_REF] Turakhia | The outlook of digital health for cardiovascular medicine: challenges but also extraordinary opportunities[END_REF][22][START_REF]The truly personal computer[END_REF][START_REF] Beam | Translating artificial intelligence into clinical care[END_REF][START_REF] Gulshan | Development and validation of a deep learning algorithm for detection of diabetic retinopathy in retinal fundus photographs[END_REF][START_REF] Wong | Artificial intelligence with deep learning technology looks into diabetic retinopathy screening[END_REF][START_REF] Bluestar | BlueStar web site[END_REF][START_REF] Syed | Traveling towards disease: transportation barriers to health care access[END_REF][START_REF] Powers | Nonemergency medical transportation: delivering care in the era of Lyft and Uber[END_REF][START_REF] Topol | The Patient Will See You Now: The Future of Medicine is in Your Hands[END_REF]. Moreover, digital health tends to reduce costs for therapists and patients and offers a health service to patients living in rural areas who have, for example, difficulties in moving around (reduced mobility, medical desertification, geographical isolation, etc.) [START_REF] Amatya | Le ou les auteurs n'ont déclaré aucun conflit d'intérêts potentiel en ce qui concerne la recherche, la paternité et/ou la publication de cet article. Efficacité des interventions de téléréadaptation chez les personnes atteintes de sclérose en plaques : une revue systématique[END_REF][START_REF] Block | Surveillance à distance de l'activité physique dans les maladies neurologiques : une revue systématique[END_REF][START_REF] Dorstyn | Applications du télécounselling dans la réadaptation des lésions de la moelle épinière : une revue systématique avec des tailles d'effet[END_REF][START_REF] Huang | Interventions de télésanté par rapport à la réadaptation cardiaque en centre de la maladie coronarienne : une revue systématique et une méta-analyse[END_REF][START_REF] Johansson | Téléréadaptation dans les soins de l'AVC : une revue systématique[END_REF][START_REF] Kairy | Une revue systématique des résultats cliniques, du processus clinique, de l'utilisation des soins de santé et des coûts associés à la téléréadaptation[END_REF][START_REF] Khan | Téléréadaptation pour les personnes atteintes de sclérose en plaques[END_REF][START_REF] Rogante | Dix ans de téléréadaptation : un aperçu de la littérature sur les technologies et les applications cliniques[END_REF][START_REF] Santos | Application de télésanté sur la rééducation des enfants et des adolescents[END_REF][START_REF] Cason | Télésanté : Un modèle de prestation de services en développement rapide pour l'ergothérapie[END_REF][START_REF] Cason | Possibilités de télésanté en ergothérapie grâce à la Loi sur les soins abordables[END_REF].

In the rehabilitation context, these new practices are based in particular on the principles of telecommunication, and more specifically on telerehabilitation [START_REF] Zampolini | Telerehabilitation: present and future[END_REF]. Tele-rehabilitation can be defined as a creative way of providing rehabilitation services from a distance using a wide variety of devices such as smartphones, digital tablets, videoconferencing, specific applications, embedded virtual reality, data transmission by video and photos or by electronic message sent by the health care provider and/or the patient [START_REF] Kairy | Une revue systématique des résultats cliniques, du processus clinique, de l'utilisation des soins de santé et des coûts associés à la téléréadaptation[END_REF][START_REF] Brennan | Un plan directeur pour les directives de téléréadaptation[END_REF][START_REF] Mccue | Améliorer la qualité de vie grâce à la téléréadaptation[END_REF]. The usefulness of digital devices in the short-and medium-term follow-up of neurological patients [START_REF]Telecommunication and rehabilitation among patients with multiple sclerosis: access and willingness to use[END_REF] or post orthopaedic surgery patients [START_REF] Fascio | Early virtual-reality-based home rehabilitation after total hip arthroplasty: a randomized controlled trial[END_REF] has been demonstrated. Indeed, the use of NTICs by patients has been shown to improve cognitive function in patients with multiple sclerosis [START_REF] Wicks | Use of an online community to develop patient-reported outcome instruments: the Multiple Sclerosis Treatment Adherence Questionnaire (MS-TAQ)[END_REF][START_REF] Goverover | Actual reality: a new approach to functional assessment in persons with multiple sclerosis[END_REF][START_REF] Negreiros | A brief neuropsychological screening test battery for cognitive dysfunction in Brazilian multiple sclerosis patients[END_REF][START_REF] Younes | Internet-based cognitive testing in multiple sclerosis[END_REF], and to be more available and accessible than with conventional methods. Furthermore, it has been shown that assessments by face-to-face professionals compared to tele-rehabilitation provided the same results [START_REF] Biebl | App-based feedback for rehabilitation exercise correction in patients with knee or hip osteoarthritis: prospective cohort study[END_REF], with similar clinical outcomes on pain care, fatigue, motor function, physical activity assessments between traditional and tele-rehabilitation [START_REF] Mckeon | SP Élargir le rôle de la technologie dans la réadaptation Après le remplacement de l'articulation des membres inférieurs : une revue systématique[END_REF][START_REF] Agostini | Télérééducation et récupération de la fonction motrice : A revue systématique et méta-analyse[END_REF][START_REF] Cottrell | TG La téléréadaptation en temps réel pour le traitement des affections musculo-squelettiques est efficace et comparable à la pratique standard : une revue systématique et une méta-analyse[END_REF][START_REF] Shukla | Rôle de la téléréadaptation chez les patients après une arthroplastie totale du genou : preuves d'une revue systématique de la littérature et d'une méta-analyse[END_REF][START_REF] Wang | SW L'efficacité de la téléréadaptation sur Internet chez les patients après une arthroplastie totale de l'articulation : une revue systématique et une méta-analyse d'essais contrôlés randomisés[END_REF].

However, many technological and societal barriers remain and limit the deployment of telerehabilitation. For example, the devices used to deliver therapeutic services (e.g., smartphone or digital tablet with applications) are unfortunately currently not sufficiently adapted and flexible to be delivered from a distance, which reduces their use and especially the engagement of patient and clinician users.

The aim of this scoping review is to highlight the technological used in digital health over the last 10 years in patients with pre-operative hip OA, more particularly in the tele-rehabilitation care.

II. METHODS

A. Protocol

This scoping review was performed according to the PRISMA-ScR (Preffered Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews) [START_REF] Tricco | PRISMA extension for scoping reviews (PRISMA-ScR): checklist and explanation[END_REF].

B. Search strategy and article selection

This scoping review search was carried out using the following electronic data bases: MEDLINE, PubMed, Scopus, PEDro and Web of sciences; and using a combination of keywords related to « "osteoarthritis", "hip osteoarthritis", "pre-operation", "rehabilitation", "tele-rehabilitation", "digital health", "telecommunication". The search strategy was between the years 2013 to 2023, namely over 10 years. Only publications in which the participants were seniors adults and elderly (40-80 years) with hip OA were included. Other eligibility criteria were: observational or experimental studies (e.g. randomised controlled trials, before/after studies), articles published in English. The articles were excluded if they were not available as full text commentaries or conference abstracts, or if the patients had undergone hip replacement surgery / hip arthroplasty. The exclusion criteria were: not complete articles, study of patients with OA other than the hip and those, although, there is the use of telecommunication tools, studies on patients with hip arthroplasty, patients under 40 years (Fig. 1).

C. Data extraction and analyses

The research on the various databases was carried out by a member of the research team (NO). Any duplications were removed with the software Zotero. Titles and abstracts were then reviewed by two independent members (NO and LW) of the research team, based on the inclusion and exclusion criteria (Fig. 1). For all studies that met our inclusion criteria, the full text was retrieved, analyzed and evaluated by the same two authors. Any conflict was resolved by discussion. For all publications meeting the inclusion criteria, two authors (NO and LW) independently extracted information using PICOT criteria (Table I). These criteria consist of five points: Population (P), Intervention (I), Comparison (C), Outcomes (O), Temporality (T). All extracted information was validated between the two authors (NO and LW) confirming that the data extracted was accurate and complete. Studies presenting the results from the same group of participants were considered a single study and the results were extracted together.

In order to assess the relevance of proposed therapies for telereadaptation in elderly with hip OA, the following variables were extracted.

Self-report measures of function assessment: Western Ontario and McMaster

(WOMAC index) [START_REF] Allen | Osteoarthritis physical activity care pathway (OA-PCP): results of a feasibility trial[END_REF], [START_REF] Bennell | Effects of adding an internet-based pain coping skills training protocol to a standardized education and exercise program for people with persistent hip pain (HOPE trial): randomized controlled trial protocol[END_REF], [START_REF] Claassen | Preparing for an orthopedic consultation using an eHealth tool: a randomized controlled trial in patients with hip and knee osteoarthritis[END_REF], [START_REF] Lawford | Consumer perceptions of and willingness to use remotely delivered service models for exercise management of knee and hip osteoarthritis: A cross-sectional survey[END_REF], [START_REF] Martinsen | Effect of a mHealth exercise intervention compared with supervised exercise therapy in osteoarthritis management: protocol of the DigiOA trial[END_REF],Hip and Osteoarthritis Outcome Score (HOOS) [START_REF] Bossen | Effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis: randomized controlled trial[END_REF], [START_REF] Bossen | The usability and preliminary effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis[END_REF], [START_REF] Jönsson | Factors associated with clinically relevant pain reduction after a self-management program including education and exercise for people with knee and/or hip osteoarthritis: Data from the BOA register[END_REF], [START_REF] Joseph | The AktiWeb study: feasibility of a web-based exercise program delivered by a patient organisation to patients with hip and/or knee osteoarthritis[END_REF], [START_REF] Lawford | Consumer perceptions of and willingness to use remotely delivered service models for exercise management of knee and hip osteoarthritis: A cross-sectional survey[END_REF], [START_REF] Östlind | Experiences of activity monitoring and perceptions of digital support among working individuals with hip and knee osteoarthritis-a focus group study[END_REF], [START_REF] Pelle | Use and usability of the dr. Bart app and its relation with health care utilisation and clinical outcomes in people with knee and/or hip osteoarthritis[END_REF], [START_REF] Saragiotto | Telerehabilitation for hip or knee osteoarthritis[END_REF], Assessment of Quality of Life (AQoL) [START_REF] Bennell | Effects of adding an internet-based pain coping skills training protocol to a standardized education and exercise program for people with persistent hip pain (HOPE trial): randomized controlled trial protocol[END_REF], [START_REF] Cronström | I would never have done it if it hadn't been digital': a qualitative study on patients' experiences of a digital management programme for hip and knee osteoarthritis in Sweden[END_REF], [START_REF] Jönsson | Factors associated with clinically relevant pain reduction after a self-management program including education and exercise for people with knee and/or hip osteoarthritis: Data from the BOA register[END_REF], [START_REF] Joseph | The AktiWeb study: feasibility of a web-based exercise program delivered by a patient organisation to patients with hip and/or knee osteoarthritis[END_REF], [START_REF] Lawford | Consumer perceptions of and willingness to use remotely delivered service models for exercise management of knee and hip osteoarthritis: A cross-sectional survey[END_REF], [START_REF] Östlind | Experiences of activity monitoring and perceptions of digital support among working individuals with hip and knee osteoarthritis-a focus group study[END_REF], Visual Analogic Scales (VAS -Pain) [START_REF] Allen | Osteoarthritis physical activity care pathway (OA-PCP): results of a feasibility trial[END_REF], [START_REF] Bennell | Effects of adding an internet-based pain coping skills training protocol to a standardized education and exercise program for people with persistent hip pain (HOPE trial): randomized controlled trial protocol[END_REF], [START_REF] Bossen | Effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis: randomized controlled trial[END_REF], [START_REF] Cronström | I would never have done it if it hadn't been digital': a qualitative study on patients' experiences of a digital management programme for hip and knee osteoarthritis in Sweden[END_REF], [START_REF] Dahlberg | A web-based platform for patients with osteoarthritis of the hip and knee: a pilot study[END_REF], [START_REF] Dahlberg | Improving osteoarthritis care by digital means-Effects of a digital self-management program after 24-or 48-weeks of treatment[END_REF], [START_REF] Jönsson | Factors associated with clinically relevant pain reduction after a self-management program including education and exercise for people with knee and/or hip osteoarthritis: Data from the BOA register[END_REF], [START_REF] Lawford | Consumer perceptions of and willingness to use remotely delivered service models for exercise management of knee and hip osteoarthritis: A cross-sectional survey[END_REF], [START_REF] Martinsen | Effect of a mHealth exercise intervention compared with supervised exercise therapy in osteoarthritis management: protocol of the DigiOA trial[END_REF], [START_REF] Saragiotto | Telerehabilitation for hip or knee osteoarthritis[END_REF], Arthritis Self-Efficacy Scale (ASES) [START_REF] Bennell | Effects of adding an internet-based pain coping skills training protocol to a standardized education and exercise program for people with persistent hip pain (HOPE trial): randomized controlled trial protocol[END_REF], [START_REF] Jönsson | Factors associated with clinically relevant pain reduction after a self-management program including education and exercise for people with knee and/or hip osteoarthritis: Data from the BOA register[END_REF],Physical Activity Scale for the Elderly (PASE) [START_REF] Bennell | Effects of adding an internet-based pain coping skills training protocol to a standardized education and exercise program for people with persistent hip pain (HOPE trial): randomized controlled trial protocol[END_REF], [START_REF] Bossen | Effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis: randomized controlled trial[END_REF].

Functional Tests: test 30 chair stand test (30CST) [START_REF] Cronström | I would never have done it if it hadn't been digital': a qualitative study on patients' experiences of a digital management programme for hip and knee osteoarthritis in Sweden[END_REF], [START_REF] Dahlberg | Improving osteoarthritis care by digital means-Effects of a digital self-management program after 24-or 48-weeks of treatment[END_REF], [START_REF] Lawford | Consumer perceptions of and willingness to use remotely delivered service models for exercise management of knee and hip osteoarthritis: A cross-sectional survey[END_REF], [START_REF] Martinsen | Effect of a mHealth exercise intervention compared with supervised exercise therapy in osteoarthritis management: protocol of the DigiOA trial[END_REF], [START_REF] Muñoz-Fonseca | Efectos en la capacidad funcional de un programa de ejercicio físico terapéutico basado en telesalud en personas con diagnóstico de osteoartritis de rodilla y cadera[END_REF]. Short Physical Performance Battery (SPPB) [START_REF] Martinsen | Effect of a mHealth exercise intervention compared with supervised exercise therapy in osteoarthritis management: protocol of the DigiOA trial[END_REF], Senior Fitness Test (SFT) [START_REF] Martinsen | Effect of a mHealth exercise intervention compared with supervised exercise therapy in osteoarthritis management: protocol of the DigiOA trial[END_REF], Number of steps with accelerometer wrist [START_REF] Allen | Osteoarthritis physical activity care pathway (OA-PCP): results of a feasibility trial[END_REF], [START_REF] Joseph | The AktiWeb study: feasibility of a web-based exercise program delivered by a patient organisation to patients with hip and/or knee osteoarthritis[END_REF], [START_REF] Muñoz-Fonseca | Efectos en la capacidad funcional de un programa de ejercicio físico terapéutico basado en telesalud en personas con diagnóstico de osteoartritis de rodilla y cadera[END_REF], on hip [START_REF] Jönsson | Factors associated with clinically relevant pain reduction after a self-management program including education and exercise for people with knee and/or hip osteoarthritis: Data from the BOA register[END_REF].

Telerehabilitation assessment: semistructured interviews assessing acceptability and acceptance face-to-face or virtually interviews with content analysis. Characteristics and indicators of the studies were collected and analysed. [START_REF] Cronström | I would never have done it if it hadn't been digital': a qualitative study on patients' experiences of a digital management programme for hip and knee osteoarthritis in Sweden[END_REF], [START_REF] Pelle | Use and usability of the dr. Bart app and its relation with health care utilisation and clinical outcomes in people with knee and/or hip osteoarthritis[END_REF], System Usability Scale (SUS) [START_REF] Bossen | The usability and preliminary effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis[END_REF], [START_REF] Jönsson | Factors associated with clinically relevant pain reduction after a self-management program including education and exercise for people with knee and/or hip osteoarthritis: Data from the BOA register[END_REF], [START_REF] Östlind | Experiences of activity monitoring and perceptions of digital support among working individuals with hip and knee osteoarthritis-a focus group study[END_REF], The Telemedicine Perception Questionnaire (TMPQ) [START_REF] Lawford | Physical therapists' perceptions of telephone-and internet video-mediated service models for exercise management of people with osteoarthritis[END_REF], [START_REF] Kloek | Cost-effectiveness of a blended physiotherapy intervention compared to usual physiotherapy in patients with hip and/or knee osteoarthritis: a cluster randomized controlled trial[END_REF].

D. Study validity assessment

Two authors (NO and LW) independently analysed the methodological quality of each study using the Newcastle-Ottawa scale for non-randomised controlled trials (n=6) and cohort studies (n=1) (Table IIa) and finally the PEDro scale for randomised controlled trials (n=11) (Table IIb). For the Newcastle-Ottawa scale, each study could obtain a maximum of nine stars: 4 stars for study group selection, 1 star for group comparability and 3 stars for exposure or outcome of interest. For the randomised crossover studies included in this scoping review, the PEDro scale was used. This tool consists of 11 questions that are answered with "yes" or "no", with a higher number of "yes" answers representing a better reliability of the article.

III. RESULTS

A. Search results

The electronic database search produced 128 publications for the selection. Twenty-four duplicates were removed from the selection using Zotero, leaving 104 articles to be processed (Fig. 1).

Of the 104 articles, 85 were excluded because they did not meet the inclusion criteria: either the study only involved patients with knee OA, or the patients had undergone arthroplasty, or they did not correspond to the themes of our aim study. Articles with a focus on digital health in general have been removed from the selection. In summary, 19 articles [START_REF] Allen | Osteoarthritis physical activity care pathway (OA-PCP): results of a feasibility trial[END_REF][START_REF] Lawford | Physical therapists' perceptions of telephone-and internet video-mediated service models for exercise management of people with osteoarthritis[END_REF][START_REF] Bennell | Effects of adding an internet-based pain coping skills training protocol to a standardized education and exercise program for people with persistent hip pain (HOPE trial): randomized controlled trial protocol[END_REF][START_REF] Bernetti | SHORT PAPER Medical management of osteoarthritis during the CO-VID-19 pandemic: a challenge for the present and the future[END_REF][START_REF] Bossen | Effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis: randomized controlled trial[END_REF][START_REF] Bossen | The usability and preliminary effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis[END_REF][START_REF] Claassen | Preparing for an orthopedic consultation using an eHealth tool: a randomized controlled trial in patients with hip and knee osteoarthritis[END_REF][START_REF] Cronström | I would never have done it if it hadn't been digital': a qualitative study on patients' experiences of a digital management programme for hip and knee osteoarthritis in Sweden[END_REF][START_REF] Dahlberg | A web-based platform for patients with osteoarthritis of the hip and knee: a pilot study[END_REF][START_REF] Dahlberg | Improving osteoarthritis care by digital means-Effects of a digital self-management program after 24-or 48-weeks of treatment[END_REF][START_REF] Jönsson | Factors associated with clinically relevant pain reduction after a self-management program including education and exercise for people with knee and/or hip osteoarthritis: Data from the BOA register[END_REF][START_REF] Joseph | The AktiWeb study: feasibility of a web-based exercise program delivered by a patient organisation to patients with hip and/or knee osteoarthritis[END_REF][START_REF] Kloek | Cost-effectiveness of a blended physiotherapy intervention compared to usual physiotherapy in patients with hip and/or knee osteoarthritis: a cluster randomized controlled trial[END_REF][START_REF] Lawford | Consumer perceptions of and willingness to use remotely delivered service models for exercise management of knee and hip osteoarthritis: A cross-sectional survey[END_REF][START_REF] Martinsen | Effect of a mHealth exercise intervention compared with supervised exercise therapy in osteoarthritis management: protocol of the DigiOA trial[END_REF][START_REF] Muñoz-Fonseca | Efectos en la capacidad funcional de un programa de ejercicio físico terapéutico basado en telesalud en personas con diagnóstico de osteoartritis de rodilla y cadera[END_REF][START_REF] Östlind | Experiences of activity monitoring and perceptions of digital support among working individuals with hip and knee osteoarthritis-a focus group study[END_REF][START_REF] Pelle | Use and usability of the dr. Bart app and its relation with health care utilisation and clinical outcomes in people with knee and/or hip osteoarthritis[END_REF][START_REF] Saragiotto | Telerehabilitation for hip or knee osteoarthritis[END_REF] were processed in full text (Fig. 1).

Of the 19 articles included (Fig. 2), 5 from the Netherlands [START_REF] Bossen | Effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis: randomized controlled trial[END_REF], [START_REF] Bossen | The usability and preliminary effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis[END_REF], [START_REF] Claassen | Preparing for an orthopedic consultation using an eHealth tool: a randomized controlled trial in patients with hip and knee osteoarthritis[END_REF], [START_REF] Joseph | The AktiWeb study: feasibility of a web-based exercise program delivered by a patient organisation to patients with hip and/or knee osteoarthritis[END_REF], [START_REF] Östlind | Experiences of activity monitoring and perceptions of digital support among working individuals with hip and knee osteoarthritis-a focus group study[END_REF] (i.e. 26%), 4 from Sweden [START_REF] Cronström | I would never have done it if it hadn't been digital': a qualitative study on patients' experiences of a digital management programme for hip and knee osteoarthritis in Sweden[END_REF], [START_REF] Dahlberg | A web-based platform for patients with osteoarthritis of the hip and knee: a pilot study[END_REF], [START_REF] Dahlberg | Improving osteoarthritis care by digital means-Effects of a digital self-management program after 24-or 48-weeks of treatment[END_REF], [START_REF] Muñoz-Fonseca | Efectos en la capacidad funcional de un programa de ejercicio físico terapéutico basado en telesalud en personas con diagnóstico de osteoartritis de rodilla y cadera[END_REF] Fourteen of the selected articles were research articles (i.e. 74% of the selected articles), 5 were research protocols (i.e. 21%), and 1 was a short paper of 4 pages (i.e. 5%).

Of the 19 selected articles, all were about hip OA and digital health monitoring for patients aged between 40 and 80 years depending on the study. The sample size also varied from 19 to 330 users. From the point of view of study characteristics, 5 were observational studies, and 14 were interventions or experimental studies. Different means of communication were used: video calls with professional and video exercices (n=8) [START_REF] Cronström | I would never have done it if it hadn't been digital': a qualitative study on patients' experiences of a digital management programme for hip and knee osteoarthritis in Sweden[END_REF][START_REF] Dahlberg | A web-based platform for patients with osteoarthritis of the hip and knee: a pilot study[END_REF][START_REF] Dahlberg | Improving osteoarthritis care by digital means-Effects of a digital self-management program after 24-or 48-weeks of treatment[END_REF], [START_REF] Joseph | The AktiWeb study: feasibility of a web-based exercise program delivered by a patient organisation to patients with hip and/or knee osteoarthritis[END_REF], [START_REF] Kloek | Cost-effectiveness of a blended physiotherapy intervention compared to usual physiotherapy in patients with hip and/or knee osteoarthritis: a cluster randomized controlled trial[END_REF], [START_REF] Martinsen | Effect of a mHealth exercise intervention compared with supervised exercise therapy in osteoarthritis management: protocol of the DigiOA trial[END_REF], [START_REF] Muñoz-Fonseca | Efectos en la capacidad funcional de un programa de ejercicio físico terapéutico basado en telesalud en personas con diagnóstico de osteoartritis de rodilla y cadera[END_REF], [START_REF] Pelle | Use and usability of the dr. Bart app and its relation with health care utilisation and clinical outcomes in people with knee and/or hip osteoarthritis[END_REF] applications (n=4) [START_REF] Lawford | Consumer perceptions of and willingness to use remotely delivered service models for exercise management of knee and hip osteoarthritis: A cross-sectional survey[END_REF], [START_REF] Muñoz-Fonseca | Efectos en la capacidad funcional de un programa de ejercicio físico terapéutico basado en telesalud en personas con diagnóstico de osteoartritis de rodilla y cadera[END_REF], [START_REF] Östlind | Experiences of activity monitoring and perceptions of digital support among working individuals with hip and knee osteoarthritis-a focus group study[END_REF], [START_REF] Saragiotto | Telerehabilitation for hip or knee osteoarthritis[END_REF], website (n=10) [START_REF] Allen | Osteoarthritis physical activity care pathway (OA-PCP): results of a feasibility trial[END_REF], [START_REF] Bennell | Effects of adding an internet-based pain coping skills training protocol to a standardized education and exercise program for people with persistent hip pain (HOPE trial): randomized controlled trial protocol[END_REF], [START_REF] Bossen | Effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis: randomized controlled trial[END_REF][START_REF] Bossen | The usability and preliminary effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis[END_REF][START_REF] Claassen | Preparing for an orthopedic consultation using an eHealth tool: a randomized controlled trial in patients with hip and knee osteoarthritis[END_REF][START_REF] Cronström | I would never have done it if it hadn't been digital': a qualitative study on patients' experiences of a digital management programme for hip and knee osteoarthritis in Sweden[END_REF][START_REF] Dahlberg | A web-based platform for patients with osteoarthritis of the hip and knee: a pilot study[END_REF][START_REF] Dahlberg | Improving osteoarthritis care by digital means-Effects of a digital self-management program after 24-or 48-weeks of treatment[END_REF][START_REF] Jönsson | Factors associated with clinically relevant pain reduction after a self-management program including education and exercise for people with knee and/or hip osteoarthritis: Data from the BOA register[END_REF][START_REF] Joseph | The AktiWeb study: feasibility of a web-based exercise program delivered by a patient organisation to patients with hip and/or knee osteoarthritis[END_REF] phone calls (n=3) [START_REF] Allen | Osteoarthritis physical activity care pathway (OA-PCP): results of a feasibility trial[END_REF], [START_REF] Cronström | I would never have done it if it hadn't been digital': a qualitative study on patients' experiences of a digital management programme for hip and knee osteoarthritis in Sweden[END_REF], [START_REF] Kloek | Cost-effectiveness of a blended physiotherapy intervention compared to usual physiotherapy in patients with hip and/or knee osteoarthritis: a cluster randomized controlled trial[END_REF], social networks (n=2) [START_REF] Cronström | I would never have done it if it hadn't been digital': a qualitative study on patients' experiences of a digital management programme for hip and knee osteoarthritis in Sweden[END_REF], [START_REF] Martinsen | Effect of a mHealth exercise intervention compared with supervised exercise therapy in osteoarthritis management: protocol of the DigiOA trial[END_REF], emails (n=6) [START_REF] Allen | Osteoarthritis physical activity care pathway (OA-PCP): results of a feasibility trial[END_REF], [START_REF] Bossen | The usability and preliminary effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis[END_REF][START_REF] Claassen | Preparing for an orthopedic consultation using an eHealth tool: a randomized controlled trial in patients with hip and knee osteoarthritis[END_REF][START_REF] Cronström | I would never have done it if it hadn't been digital': a qualitative study on patients' experiences of a digital management programme for hip and knee osteoarthritis in Sweden[END_REF][START_REF] Dahlberg | A web-based platform for patients with osteoarthritis of the hip and knee: a pilot study[END_REF][START_REF] Dahlberg | Improving osteoarthritis care by digital means-Effects of a digital self-management program after 24-or 48-weeks of treatment[END_REF]. As we can see above, in some studies more than one means of communication was used by the researchers (Fig. 3).

B. Intervention

The selected articles show that physical exercise have been implemented in different ways. For example, [START_REF] Allen | Osteoarthritis physical activity care pathway (OA-PCP): results of a feasibility trial[END_REF], [START_REF] Bennell | Effects of adding an internet-based pain coping skills training protocol to a standardized education and exercise program for people with persistent hip pain (HOPE trial): randomized controlled trial protocol[END_REF], [START_REF] Bossen | Effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis: randomized controlled trial[END_REF], [START_REF] Bossen | The usability and preliminary effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis[END_REF], [START_REF] Jönsson | Factors associated with clinically relevant pain reduction after a self-management program including education and exercise for people with knee and/or hip osteoarthritis: Data from the BOA register[END_REF] used explanatory cards with a representation of the exercises that could be printed out by the patients; [START_REF] Cronström | I would never have done it if it hadn't been digital': a qualitative study on patients' experiences of a digital management programme for hip and knee osteoarthritis in Sweden[END_REF], [START_REF] Dahlberg | A web-based platform for patients with osteoarthritis of the hip and knee: a pilot study[END_REF], [START_REF] Dahlberg | Improving osteoarthritis care by digital means-Effects of a digital self-management program after 24-or 48-weeks of treatment[END_REF], [START_REF] Joseph | The AktiWeb study: feasibility of a web-based exercise program delivered by a patient organisation to patients with hip and/or knee osteoarthritis[END_REF], [START_REF] Martinsen | Effect of a mHealth exercise intervention compared with supervised exercise therapy in osteoarthritis management: protocol of the DigiOA trial[END_REF], [START_REF] Muñoz-Fonseca | Efectos en la capacidad funcional de un programa de ejercicio físico terapéutico basado en telesalud en personas con diagnóstico de osteoartritis de rodilla y cadera[END_REF], [START_REF] Pelle | Use and usability of the dr. Bart app and its relation with health care utilisation and clinical outcomes in people with knee and/or hip osteoarthritis[END_REF] used explanatory videos for the implementation of a PA program. Others, such as [START_REF] Lawford | Consumer perceptions of and willingness to use remotely delivered service models for exercise management of knee and hip osteoarthritis: A cross-sectional survey[END_REF], used text, audio and video instructions for each exercise in their program. In addition to providing a library of textual exercise information, [START_REF] Östlind | Experiences of activity monitoring and perceptions of digital support among working individuals with hip and knee osteoarthritis-a focus group study[END_REF] used a "small habit method", e.g. "after lunch, I get up from my chair 12 times to train my leg muscles".

The exercise program were mainly based on functional/balance exercises (i.e., standing weight transfers, one-legged stance), muscle strengthening (i.e., hip abduction, i.e., hip extensors, i.e., quadriceps) and stretching/flexibility (i.e., standing hip flexors), and exercises such as seated knee extension, partial squats, isometric partial wall squats, sit-to-stand, etc.

The evaluation questionnaires on their perception of effort or pain after performing the exercises were offered to patients in order to assess their physical feelings. Moreover, the evaluation of the motor function, the reduction of pain in patients, the improvement of the quality of life or the evaluation of the acceptability and feasibility of a digital monitoring program were proposed in their clinical care followup. All the variables analyzed are explained and illustrated in the methodology section.

C. Evaluations

The (Fig. 4) shows us that 15 studies used selfreport measures of function such as questionnaires or scales [START_REF] Allen | Osteoarthritis physical activity care pathway (OA-PCP): results of a feasibility trial[END_REF], [START_REF] Bennell | Effects of adding an internet-based pain coping skills training protocol to a standardized education and exercise program for people with persistent hip pain (HOPE trial): randomized controlled trial protocol[END_REF], [START_REF] Bossen | Effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis: randomized controlled trial[END_REF], [START_REF] Cronström | I would never have done it if it hadn't been digital': a qualitative study on patients' experiences of a digital management programme for hip and knee osteoarthritis in Sweden[END_REF], [START_REF] Dahlberg | A web-based platform for patients with osteoarthritis of the hip and knee: a pilot study[END_REF], [START_REF] Dahlberg | Improving osteoarthritis care by digital means-Effects of a digital self-management program after 24-or 48-weeks of treatment[END_REF], [START_REF] Jönsson | Factors associated with clinically relevant pain reduction after a self-management program including education and exercise for people with knee and/or hip osteoarthritis: Data from the BOA register[END_REF], [START_REF] Joseph | The AktiWeb study: feasibility of a web-based exercise program delivered by a patient organisation to patients with hip and/or knee osteoarthritis[END_REF], [START_REF] Lawford | Consumer perceptions of and willingness to use remotely delivered service models for exercise management of knee and hip osteoarthritis: A cross-sectional survey[END_REF], [START_REF] Martinsen | Effect of a mHealth exercise intervention compared with supervised exercise therapy in osteoarthritis management: protocol of the DigiOA trial[END_REF], [START_REF] Muñoz-Fonseca | Efectos en la capacidad funcional de un programa de ejercicio físico terapéutico basado en telesalud en personas con diagnóstico de osteoartritis de rodilla y cadera[END_REF], [START_REF] Östlind | Experiences of activity monitoring and perceptions of digital support among working individuals with hip and knee osteoarthritis-a focus group study[END_REF], [START_REF] Saragiotto | Telerehabilitation for hip or knee osteoarthritis[END_REF].

Eight studies used functional tests [START_REF] Allen | Osteoarthritis physical activity care pathway (OA-PCP): results of a feasibility trial[END_REF], [START_REF] Cronström | I would never have done it if it hadn't been digital': a qualitative study on patients' experiences of a digital management programme for hip and knee osteoarthritis in Sweden[END_REF], [START_REF] Dahlberg | Improving osteoarthritis care by digital means-Effects of a digital self-management program after 24-or 48-weeks of treatment[END_REF], [START_REF] Jönsson | Factors associated with clinically relevant pain reduction after a self-management program including education and exercise for people with knee and/or hip osteoarthritis: Data from the BOA register[END_REF], [START_REF] Joseph | The AktiWeb study: feasibility of a web-based exercise program delivered by a patient organisation to patients with hip and/or knee osteoarthritis[END_REF], [START_REF] Lawford | Consumer perceptions of and willingness to use remotely delivered service models for exercise management of knee and hip osteoarthritis: A cross-sectional survey[END_REF], [START_REF] Martinsen | Effect of a mHealth exercise intervention compared with supervised exercise therapy in osteoarthritis management: protocol of the DigiOA trial[END_REF], [START_REF] Muñoz-Fonseca | Efectos en la capacidad funcional de un programa de ejercicio físico terapéutico basado en telesalud en personas con diagnóstico de osteoartritis de rodilla y cadera[END_REF]. And finally, 7 studies used assessments of tele-rehabilitation through interviews, or questionnaires as well [START_REF] Lawford | Physical therapists' perceptions of telephone-and internet video-mediated service models for exercise management of people with osteoarthritis[END_REF], [START_REF] Bossen | The usability and preliminary effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis[END_REF], [START_REF] Cronström | I would never have done it if it hadn't been digital': a qualitative study on patients' experiences of a digital management programme for hip and knee osteoarthritis in Sweden[END_REF], [START_REF] Jönsson | Factors associated with clinically relevant pain reduction after a self-management program including education and exercise for people with knee and/or hip osteoarthritis: Data from the BOA register[END_REF], [START_REF] Kloek | Cost-effectiveness of a blended physiotherapy intervention compared to usual physiotherapy in patients with hip and/or knee osteoarthritis: a cluster randomized controlled trial[END_REF], [START_REF] Östlind | Experiences of activity monitoring and perceptions of digital support among working individuals with hip and knee osteoarthritis-a focus group study[END_REF], [START_REF] Pelle | Use and usability of the dr. Bart app and its relation with health care utilisation and clinical outcomes in people with knee and/or hip osteoarthritis[END_REF].

Indeed, as we can see some studies have used several assessments in their methods. [START_REF] Allen | Osteoarthritis physical activity care pathway (OA-PCP): results of a feasibility trial[END_REF], [START_REF] Bennell | Effects of adding an internet-based pain coping skills training protocol to a standardized education and exercise program for people with persistent hip pain (HOPE trial): randomized controlled trial protocol[END_REF], [START_REF] Bossen | Effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis: randomized controlled trial[END_REF], [START_REF] Cronström | I would never have done it if it hadn't been digital': a qualitative study on patients' experiences of a digital management programme for hip and knee osteoarthritis in Sweden[END_REF], [START_REF] Dahlberg | A web-based platform for patients with osteoarthritis of the hip and knee: a pilot study[END_REF], [START_REF] Dahlberg | Improving osteoarthritis care by digital means-Effects of a digital self-management program after 24-or 48-weeks of treatment[END_REF], [START_REF] Jönsson | Factors associated with clinically relevant pain reduction after a self-management program including education and exercise for people with knee and/or hip osteoarthritis: Data from the BOA register[END_REF], [START_REF] Joseph | The AktiWeb study: feasibility of a web-based exercise program delivered by a patient organisation to patients with hip and/or knee osteoarthritis[END_REF], [START_REF] Lawford | Consumer perceptions of and willingness to use remotely delivered service models for exercise management of knee and hip osteoarthritis: A cross-sectional survey[END_REF], [START_REF] Martinsen | Effect of a mHealth exercise intervention compared with supervised exercise therapy in osteoarthritis management: protocol of the DigiOA trial[END_REF], [START_REF] Muñoz-Fonseca | Efectos en la capacidad funcional de un programa de ejercicio físico terapéutico basado en telesalud en personas con diagnóstico de osteoartritis de rodilla y cadera[END_REF], [START_REF] Östlind | Experiences of activity monitoring and perceptions of digital support among working individuals with hip and knee osteoarthritis-a focus group study[END_REF]. Eight [START_REF] Bennell | Effects of adding an internet-based pain coping skills training protocol to a standardized education and exercise program for people with persistent hip pain (HOPE trial): randomized controlled trial protocol[END_REF], [START_REF] Bossen | Effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis: randomized controlled trial[END_REF], [START_REF] Bossen | The usability and preliminary effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis[END_REF], [START_REF] Claassen | Preparing for an orthopedic consultation using an eHealth tool: a randomized controlled trial in patients with hip and knee osteoarthritis[END_REF], [START_REF] Cronström | I would never have done it if it hadn't been digital': a qualitative study on patients' experiences of a digital management programme for hip and knee osteoarthritis in Sweden[END_REF], [START_REF] Joseph | The AktiWeb study: feasibility of a web-based exercise program delivered by a patient organisation to patients with hip and/or knee osteoarthritis[END_REF], [START_REF] Martinsen | Effect of a mHealth exercise intervention compared with supervised exercise therapy in osteoarthritis management: protocol of the DigiOA trial[END_REF], [START_REF] Muñoz-Fonseca | Efectos en la capacidad funcional de un programa de ejercicio físico terapéutico basado en telesalud en personas con diagnóstico de osteoartritis de rodilla y cadera[END_REF], [START_REF] Saragiotto | Telerehabilitation for hip or knee osteoarthritis[END_REF] studies used a protocol with a control group and an experimental group, 6 studies [START_REF] Allen | Osteoarthritis physical activity care pathway (OA-PCP): results of a feasibility trial[END_REF], [START_REF] Dahlberg | A web-based platform for patients with osteoarthritis of the hip and knee: a pilot study[END_REF], [START_REF] Dahlberg | Improving osteoarthritis care by digital means-Effects of a digital self-management program after 24-or 48-weeks of treatment[END_REF], [START_REF] Jönsson | Factors associated with clinically relevant pain reduction after a self-management program including education and exercise for people with knee and/or hip osteoarthritis: Data from the BOA register[END_REF], [START_REF] Lawford | Consumer perceptions of and willingness to use remotely delivered service models for exercise management of knee and hip osteoarthritis: A cross-sectional survey[END_REF], [START_REF] Östlind | Experiences of activity monitoring and perceptions of digital support among working individuals with hip and knee osteoarthritis-a focus group study[END_REF], compared outcomes within a single group. The aim of studies was either to assess the acceptance and feasibility of implementing a follow-up program in patients (n=4) [START_REF] Lawford | Physical therapists' perceptions of telephone-and internet video-mediated service models for exercise management of people with osteoarthritis[END_REF], [START_REF] Jönsson | Factors associated with clinically relevant pain reduction after a self-management program including education and exercise for people with knee and/or hip osteoarthritis: Data from the BOA register[END_REF], [START_REF] Kloek | Cost-effectiveness of a blended physiotherapy intervention compared to usual physiotherapy in patients with hip and/or knee osteoarthritis: a cluster randomized controlled trial[END_REF], [START_REF] Pelle | Use and usability of the dr. Bart app and its relation with health care utilisation and clinical outcomes in people with knee and/or hip osteoarthritis[END_REF] and, a study [START_REF] Bernetti | SHORT PAPER Medical management of osteoarthritis during the CO-VID-19 pandemic: a challenge for the present and the future[END_REF] to inform the implementation of telemedicine in people with hip OA. (Fig. 5). As mentioned in the methodology section, quality assessment scales for the articles were made. These scales illustrate the methodological quality of the studies set up.

The Newcastle Ottawa Scale (Table IIa) results show that 3 articles [START_REF] Lawford | Physical therapists' perceptions of telephone-and internet video-mediated service models for exercise management of people with osteoarthritis[END_REF], [START_REF] Kloek | Cost-effectiveness of a blended physiotherapy intervention compared to usual physiotherapy in patients with hip and/or knee osteoarthritis: a cluster randomized controlled trial[END_REF], [START_REF] Pelle | Use and usability of the dr. Bart app and its relation with health care utilisation and clinical outcomes in people with knee and/or hip osteoarthritis[END_REF] have 5 stars. One article [START_REF] Dahlberg | A web-based platform for patients with osteoarthritis of the hip and knee: a pilot study[END_REF] has 6 stars. And finally, 3 articles have 7 stars [START_REF] Allen | Osteoarthritis physical activity care pathway (OA-PCP): results of a feasibility trial[END_REF], [START_REF] Dahlberg | Improving osteoarthritis care by digital means-Effects of a digital self-management program after 24-or 48-weeks of treatment[END_REF], [START_REF] Jönsson | Factors associated with clinically relevant pain reduction after a self-management program including education and exercise for people with knee and/or hip osteoarthritis: Data from the BOA register[END_REF]. Moreover, according to PEDro scale (Table IIb), one article [START_REF] Östlind | Experiences of activity monitoring and perceptions of digital support among working individuals with hip and knee osteoarthritis-a focus group study[END_REF] is at level 5, 4 articles at level 6 [START_REF] Cronström | I would never have done it if it hadn't been digital': a qualitative study on patients' experiences of a digital management programme for hip and knee osteoarthritis in Sweden[END_REF], [START_REF] Lawford | Consumer perceptions of and willingness to use remotely delivered service models for exercise management of knee and hip osteoarthritis: A cross-sectional survey[END_REF], [START_REF] Muñoz-Fonseca | Efectos en la capacidad funcional de un programa de ejercicio físico terapéutico basado en telesalud en personas con diagnóstico de osteoartritis de rodilla y cadera[END_REF], [START_REF] Saragiotto | Telerehabilitation for hip or knee osteoarthritis[END_REF], 3 articles had a level 7 [START_REF] Bossen | Effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis: randomized controlled trial[END_REF], [START_REF] Bossen | The usability and preliminary effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis[END_REF], [START_REF] Martinsen | Effect of a mHealth exercise intervention compared with supervised exercise therapy in osteoarthritis management: protocol of the DigiOA trial[END_REF], and finally 3 articles with a score of 8 [START_REF] Bennell | Effects of adding an internet-based pain coping skills training protocol to a standardized education and exercise program for people with persistent hip pain (HOPE trial): randomized controlled trial protocol[END_REF], [START_REF] Claassen | Preparing for an orthopedic consultation using an eHealth tool: a randomized controlled trial in patients with hip and knee osteoarthritis[END_REF], [START_REF] Joseph | The AktiWeb study: feasibility of a web-based exercise program delivered by a patient organisation to patients with hip and/or knee osteoarthritis[END_REF]. Finally, a comparison between the means of communication used in the articles (cf. telerehabilitation, tele-consulting, etc.) and the evaluation scores of the Newcastle Ottawa Scale and PEDro scales, the results show that the care quality is higher for those that used a method of IV.

CONCLUSION AND PERSPECTIVES

The aim of this scoping review was to highlight the technologies used in the field of digital health over the last ten years in patients with hip OA, more particularly in the context of tele-rehabilitation care. Indeed, our scoping review shows that the majority of articles (12 out of 19, i.e. 60%) [START_REF] Allen | Osteoarthritis physical activity care pathway (OA-PCP): results of a feasibility trial[END_REF], [START_REF] Bennell | Effects of adding an internet-based pain coping skills training protocol to a standardized education and exercise program for people with persistent hip pain (HOPE trial): randomized controlled trial protocol[END_REF], [START_REF] Bossen | The usability and preliminary effectiveness of a web-based physical activity intervention in patients with knee and/or hip osteoarthritis[END_REF], [START_REF] Claassen | Preparing for an orthopedic consultation using an eHealth tool: a randomized controlled trial in patients with hip and knee osteoarthritis[END_REF], [START_REF] Dahlberg | A web-based platform for patients with osteoarthritis of the hip and knee: a pilot study[END_REF], [START_REF] Dahlberg | Improving osteoarthritis care by digital means-Effects of a digital self-management program after 24-or 48-weeks of treatment[END_REF], [START_REF] Jönsson | Factors associated with clinically relevant pain reduction after a self-management program including education and exercise for people with knee and/or hip osteoarthritis: Data from the BOA register[END_REF], [START_REF] Joseph | The AktiWeb study: feasibility of a web-based exercise program delivered by a patient organisation to patients with hip and/or knee osteoarthritis[END_REF], [START_REF] Lawford | Consumer perceptions of and willingness to use remotely delivered service models for exercise management of knee and hip osteoarthritis: A cross-sectional survey[END_REF], [START_REF] Martinsen | Effect of a mHealth exercise intervention compared with supervised exercise therapy in osteoarthritis management: protocol of the DigiOA trial[END_REF], [START_REF] Östlind | Experiences of activity monitoring and perceptions of digital support among working individuals with hip and knee osteoarthritis-a focus group study[END_REF], [START_REF] Pelle | Use and usability of the dr. Bart app and its relation with health care utilisation and clinical outcomes in people with knee and/or hip osteoarthritis[END_REF] from a distance assessed symptoms, motor function and quality of life due to hip OA. In addition, these studies used many of the same variables, including the assessment questionnary which measures fatigue, pain, and quality of life.

The questionnaires used (WOMAC, HOOS, EuroQol, etc.) are recommended by the International Consortium for Health Outcomes Measurement to allow a standard assessment, based on biopsychosocial approach as the use of International Classification of Functioning, Disabil-ity and Health model [79]. Namely, the main objective of these questionnaires in research is to obtain relevant information in the most reliable and valid way [START_REF] Taherdoost | Validity and reliability of the research instrument; how to test the validation of a questionnaire/survey in research[END_REF].

In 2016, [START_REF] Whittaker | Osteoarthritis year in review 2020: rehabilitation and outcomes[END_REF] proved to us that rehabilitation in orthopaedics has been defined as any nonpharmacological or non-surgical intervention aimed at improving symptoms (pain, deformity, stiffness), motor function and/or quality of life.

The results of the studies seem to be consistent with other authors, such as [START_REF] Lin | Active video games for knee osteoarthritis improve mobility but not WOMAC score: A randomized controlled trial[END_REF] where the authors showed that technologies can provide exercise therapy, encourage adherence to physical activity [START_REF] Baker | Efficacy of Computer-Based Telephone Counseling on Long-Term Adherence to Strength Training in Elderly Patients With Knee Osteoarthritis: A Randomized Trial[END_REF] and support distance rehabilitation [START_REF] Hinman | Does telephonedelivered exercise advice and support by physiotherapists improve pain and/or function in people with knee osteoarthritis? Telecare randomised controlled trial[END_REF][START_REF] Sykes | Health classifications 1-an introduction to the ICF[END_REF].Moreover, these results are confirmed by some authors [START_REF] Lawford | Consumer perceptions of and willingness to use remotely delivered service models for exercise management of knee and hip osteoarthritis: A cross-sectional survey[END_REF] have stated that distance monitoring programming is more comprehensive as a complement to conventional therapy.Furthermore, some studies [START_REF] Kloek | Cost-effectiveness of a blended physiotherapy intervention compared to usual physiotherapy in patients with hip and/or knee osteoarthritis: a cluster randomized controlled trial[END_REF] have shown that distance monitoring allows a reduction in intervention and medication costs, compared to usual therapy.

Despite the positive results and the potential acceptability of TICs by patients in the articles included, some limitations remain in the literature. Indeed, the complexity of integrating technology into rehabilitation interventions and research has been highlighted by these authors [86]. According to them, it may be useful to consider that in most situations, individual technologies are used as a mechanism to deliver, promote or monitor the active ingredient (i.e. exercise therapy) in an intervention. It will also be essential to find ways to monitor and improve the fidelity of interventions and/or implementation. Moreover, it is important to recognize that technological aids may be less appropriate in lower socio-economic communities unless they can be adapted to the local context. These contexts pose rise to numerous problems in terms of ergonomics (e.g., interface ergonomics), use (centred on the adaptation of clinical and rehabilitation care towards patient autonomy) and finally, the reduction of social diversification (e.g., short-, medium-and long-term follow-up care). These problems must therefore be assessed and characterized specifically to propose digital devices adapted and in line with the demands of users (patients and clinicians).

In conclusion, our study was able to provide a summary of the effective care of patients with preoperative hip OA using biomedical devices and digital health technologies. This work highlights the importance and relevance to evaluate the contributions and limitations of new health technologies in order to improve future patient follow-up and thus enable recommended standard care. This also highlights the importance of considering the needs of users by adopting a usercentric approachce when designing new health technologies. Indeed, it seems relevant to us that future studies be based in particular on specific models such as the model of the International Classification of Functioning, Disability and Health [START_REF] Sykes | Health classifications 1-an introduction to the ICF[END_REF], used as a guide for setting rehabilitation objectives, planning interventions and follow-up; but also ergonomic analysis models used to quantify user needs.

Figure 1 .

 1 Figure 1. Flow Diagram.

Figure 2 .

 2 Figure 2. Distribution of articles in the countries.

Figure 3 .

 3 Figure 3. The different means of communication used.

Figure 4 .

 4 Figure 4. Variables and assessments implemented.

Figure 5 .

 5 Figure 5. Pie chart representing the distribution of items.

  and/or graphs exchanges on the physical activity program.

Table I

 I

			. PICOT criteria.
	Population	Elderly with hip osteoarthritis
	Intervention	Therapeutic and clinical care with NTICs,
		implementation of	physical activities
		programs with NTICs
	Comparison	e.g., conventional therapies vs. therapies
		with NTICs, only NTICs (before-after
		care)
	Outcomes	e.g., clinical evaluations (questionnaires,
		scores, mobility and activity scales, etc.),
		user	feedback	(satisfaction
		questionnaires)
	Temporality	pre-surgery, before stade 4 of hip OA or
		before hip arthroplasty.

TABLE IIb :

 IIb Methodological assessment of studies with the PEDro scale -a scale for assessing the quality of randomised controlled trials.


Gregorio Viera

Stéphanie Huet

Maxime Mikikian

Laifa Boufendi
email: laifa.boufendi@univ-orleans.fr

Electron diffraction and high-resolution transmission microscopy studies of nanostructured Si thin films deposited by radiofrequency dusty plasmas

Keywords: Polymorphous silicon, nanostructured, fcc, RF plasma-CVD, electron microscopy

come

Electron diffraction and high-resolution transmission microscopy studies of nanostructured Si thin films deposited by radiofrequency dusty plasmas

Introduction

The term "polymorphous Si" is used to define a new type of Si material that consists of a two-phase mixture of amorphous and ordered Si [1]. These thin films are obtained by plasma-enhanced chemical vapor deposition (PECVD) under a wide variety of plasma conditions, but always allowing the formation of Si nanoparticles in the plasma gas phase and their contribution to the growing film. Despite the heterogeneity of these films, transport properties have been found to be greatly improved when compared to standard amorphous Si (a-Si:H), thus enhancing their device applications in the solar cell domain [2].

Usually, polymorphous Si (pm-Si) films are also called hydrogenated nanostructured Si (ns-Si:H) in agreement with their high hydrogen concentration and with the nanometer size of the Si ordered domains [3]. In the following, we will use the designation of ns-Si:H.

Here, a careful analysis by TEM, HRTEM and electron diffraction is presented with the aim to clarify the specific atomic structure of these films. We have focused on the characterization of Si films deposited by square-wave modulated (SQWM) radio-frequency (rf) plasmas of SiH 4 diluted in Ar. Modulation period and process temperature were changed to obtain films with different nanostructures. The results of the present characterization were compared to that found in films deposited in continuous SiH 4 -H 2 plasmas, and in nanocrystalline Si powders grown in modulated SiH 4 -Ar plasmas. Whatever the plasma conditions, the electron diffraction images always reveal the existence of a well-defined crystalline structure different to the diamond-like structure of Si. A new Si face-centeredcubic (fcc) structure is noticed.

Experimental

n-Si:H thin films were produced in a PECVD reactor by glow discharge decomposition of SiH 4 diluted in Ar. The plasma camera was of the circularplate type with horizontal electrodes and rf power excited at 13.56 MHz. The gas flow was injected with a showerhead type rf powered electrode. The rf power source was SQWM to control the powder size. SQWM consists of alternating plasma-on periods (T ON ), during which a film is deposited on the anode and particles are formed in the plasma gas phase, with afterglow periods (T OFF ), during which the particles leave the plasma and can contribute to film deposition. T OFF was long enough to restore the initial conditions of the gas in each new cycle. On the basis of previous studies on the formation of Si powder particles [4], we chose the following parameters: 30 sccm of Ar, 1.2 sccm of SiH 4 , total pressure of 12 Pa, rf power density of 60 mW/cm 2 , and gas temperature of 100°C. The T ON was varied from 0.1 to 5 s in order to produce films with different particle size and concentration.

The particle morphology and structure were observed by conventional and high resolution transmission electron microscopy (HRTEM and TEM, respectively) and selected area electron diffraction (SAED), using a Philips CM30 microscope operating at 300kV. The samples were cross-sectional prepared using the conventional thinning method: first they are mechanically polished using abrasive materials and finally thinned with ion milling. The measurements performed on HRTEM and SAED images were previously calibrated from the analysis of the crystalline Si substrate of the n-Si:H thin films.

Results

Figure 1 shows dark field images of a thin film deposited at T ON = 5s and T G = 150°C (Fig. 1a) and those of thin films deposited at the same lower temperature T G = 100 °C but at two different plasma durations (T ON = 1 s Fig. 1b and T ON = 5 s Fig. 1c ). The films deposited at T ON = 5 s and T G =150 °C appear highly amorphous. This is in agreement with previous studies on particle formation in the plasma [4]. Therefore, this sample can be taken as a reference for the dark field analysis. The film deposited at T ON = 5 s and T G = 100°C (Fig. 1c) clearly shows a considerable increase in crystalline density. This is consistent with the emergence of distinct rings in the corresponding electron diffraction pattern (insert in the image).

In order to obtain further information about the size and density of the crystallites in the different pm-Si:H samples, we have used an image processing and analysis software to identify the bright points in the dark-field images (considered as objects) and to extract the features of these objects (quantity, area, perimeter, roundness, etc). By means of this software, the size histograms and the crystalline densities D C have been calculated (figure 2). These histograms indicate that the majority of crystallites presents dimensions inferior to 2 nm, with decreasing populations for larger grain sizes. This figure also shows that crystalline density increases when the gas temperature decreases, and even more when plasma duration increases.

Figure 3 shows the HRTEM images of the thin film deposited at T ON = 5 s and T G = 150°C (Fig. 3a), and of the film deposited at the same temperature T G = 100 °C but at two different plasma durations (T ON = 1 s Fig. 3b and T ON = 5 s Fig. 3c). The films deposited at higher temperature appear highly amorphous, while the sample deposited at 100°C contains many ordered domains limited to 3-5 planes, corroborating the average crystallite size is inferior to 2 nm. This is D C ) was also calculated from the dark field images calculated from the dark-field images (some of the ordered domains are surrounded by white circles in the image). The interplanar distances of these domains are 0.3-0.34 nm. The HRTEM image of the sample deposited at 100°C but at T ON = 5s also shows the presence of these small crystalline entities, as well as some larger crystallites up to 5 nm. These observations are commensurate with the results obtained from the dark-field images and do demonstrate the presence of ordered structures in the amorphous Si matrix of the films considered here. Comparable HRTEM images have already been reported for nanostructured Si thin films deposited using continuous rf discharges of SiH 4 highly diluted in H 2 at 100°C and at low rf power [5].

The plasma parameters for the production of these pm-Si:H films were adapted from previous reports devoted to the formation of silicon particles in Ardiluted SiH 4 discharges [4]. Three growth phases have been defined: 1. a first step of particle nucleation of around 2 nm, where particle concentration increases while their size remains constant. 2. a second phase of coagulation of particles, which gives rise to larger particles and to a drop in particle concentration. 3. a third phase (from ∼ 20-40 nm) where the coagulation is finished and particles grow more slowly by sticking of silicon radicals on their surface. These studies also showed that the gas temperature plays an important role in the process of particle formation, by delaying the appearance of the initial crystallites and, to a greater extent, the start of their coagulation.

Using the results of Boufendi et al. [4], we have estimated the characteristic times for the onset of particle nucleation (t 1 ), of coagulation (t 2 ) and of molecular sticking (t 3 ) for the three deposition temperatures considered in this study (T G = 25, 100, 150°C), which are the following: In view of these results, the sample deposited at 150°C and T ON =5s as well as the sample deposited at 100°C and T ON =1s could contain only crystallites of a few nanometers coming from the first nucleation stage. This is well demonstrated from the TEM and HRTEM photographs presented in figures 1 and 3. At this stage of particle development, the particle size remains constant with time while the concentration is known to increase. This fact could also explain why the density of crystallites found in the sample deposited at T ON = 1 s and 100°C is higher than at T ON = 5s and 150°C, since the T ON used at 100°C is more close to the onset time for particle coagulation than the T ON used at 150°C.

In addition, the sample deposited at 100°C and T ON =5s may be formed by nanoparticles just after the coagulation process. This is in agreement with the TEM image of figure 1c, which shows the presence of larger crystallites. This film contains also smaller particles of 1-2 nm (figure 2c), identified as a population of particles that started its growth later in the plasma-on period.

It is important to remark that, for the sample deposited at 100°C and at T ON =1 s, the T ON used is a little smaller than the characteristic coagulation time t 2 ≈ 2 s. Therefore, a higher density of nanocrystallites is expected for the corresponding film obtained just before particle coagulation, and this is consistent with the higher crystalline density of the samples deposited at 100°C and T ON =5.

In the insert of each image of figure 1, the corresponding selected area electron diffraction (SAED) patterns are also shown. The SAED patterns of figures 1a and 1b contain diffuse rings which can be assigned to an amorphous structure. However, for the film obtained at T ON = 5 s and at T G = 100°C, nanocrystalline features can be identified through the appearance of sharp rings. This pattern is different from the diamond-like structure of crystalline Si. After indexation, a face-centred-cubic (fcc) structure is revealed, as demonstrated by the appearance of the (111), ( 200), ( 220), (311), (331), …, diffraction rings. The lattice constant deduced from this diffraction pattern is 3.65 Å. A similar crystalline structure was found in nanostructured Si thin films deposited under continuous SiH 4 -H 2 rf plasma [5] and in Si nanometric powder [6], where nanocrystalline clusters with fcc structure were found to be embedded in an amorphous matrix.

Although it is accepted that the diamond structure is not the most stable structure for small Si crystallites of a few number of atoms (< 2 nm) [7], little information is found in the literature on the particular atomic structure of the nanoparticles created in rf plasmas. To the authors knowledge, the fcc has not been previously reported for Si nanocrystallites. This phase is generally given as unstable polytype of Si which can be obtained under high pressures [8].

The existence of the fcc crystalline lattice in the nanostructured Si thin films is not evident to explain. Other authors have also identified a lonsdaleite phase (hexagonal close-packed, hcp) [9]. The existence of stable phases for nanocrystalline Si which are usually metastable or unstable for macroscopic bulk silicon is commonly related to size effects. Moreover, other factors related to the process of particle formation by rf plasma, such as the process temperature, pressure and the inert gas dilution, may play an important role in the reconstruction of the particle structure. In addition, ns-Si:H films are highly hydrogenated [6] and the saturation of the crystallite surface with hydrogen can also influence the most stable structure.

Of very important relevance is the high similarity which exists between the hcp and fcc phases. Besides their identical packing fraction (0.74), coordination number (12), and relative nearest-neighbor (1.296, normalized to the distance in the diamond lattice), the two phases present a very similar total structural energy. When compared to the energy of the diamond structures, the difference of structural energy between the three structures is smaller than 10% [8]. The formation of anyone of these structures under particular conditions of crystal nucleation should not then be privileged. Therefore, it is reasonable that we have observed the formation of Si crystallites with fcc, while other authors had obtained samples grown by the same technique but with the hcp structure. Further research is now being undertaken to clarify the atomic structure of these polymorphous Si thin films [10].

Conclusions

TEM and HRTEM analysis on ns-Si:H thin films grown in dust-forming rf plasmas of SiH 4 diluted in Ar agrees with previous growth kinetic studies on Si nanoparticles in these plasmas, and corroborates the hypothesis that ns-Si:H films come from the simultaneous deposition of radicals and particles. Silicon crystallites of the fcc phase were clearly identified using selected area electron diffraction

Figure 1 .

 1 Figure 1. Dark-field images of as-deposited pm-Si:H films grown in rf plasmas of Ar-diluted SiH 4 under different dustforming conditions: a) T ON = 5 s and T G = 150°C; b) T ON = 1 s and T G = 100°C, and T ON = 5 s and T G =100°C. The inserts in the images show the corresponding selected area electron diffraction patterns.

Figure 2 .

 2 Figure 2. Particle size histograms deduced from the TEM images on dark field of figure 1. The crystalline density (D C ) was also calculated from the dark field images

Figure 3 .

 3 Figure 3. HRTEM photographs of as-deposited pm-Si:H film deposited at (a) T G = 150°C and T ON = 5 s, (b) T G = 100°C and T ON = 1 s and (c) T G = 100°C and T ON = 5 s. Some of the nanometric ordered domains embedded in the amorphous silicon matrix are surrounded by a white line.

Acknowledgments

This study was financed by the European Community under contract "H-Alpha Solar" N. ERK6-CT-1999-00004 and partially supported by CICYT, MAT99-0569-CO2-01 of the government of Spain (which is coordinated by Prof. Enric Bertran from the group FEMAN of the University of Barcelona). The authors thank to Juan Carlos Ferrer (from the Serveis Cientifico-Tecnics of the University of Barcelona) for their collaboration with the TEM measurements, and to Dr. Alain Pineau for helpful discussions on the electron diffraction patterns.