The SOAR (Stop OsteoARthritis) Program Proof-of-Concept Study (SOARPOC)

The Arthritis Society, Canada, Canadian Institutes of Health Research (CIHR), Michael Smith Foundation for Health Research

Adolescents and young adults who hurt their knees playing sports or doing recreational activities can develop joint damage, muscle weakness, inactivity, and weight gain which might lead to an increased risk of osteoarthritis (OA), a disabling joint condition in their later lives. Despite knowing that muscles and joints benefit from exercise, there is no proven exercise-based treatments to delay or even halt the onset of OA after a knee joint injury. The current study will assess if a physiotherapist-guided intervention called Stop OsteoARthritis (SOAR) improves knee muscle strength, physical inactivity, knee-related self-efficacy, and knee-related quality of life in people at risk for osteoarthritis due to a past knee injury. A total of 70 former knee injury participants will be randomly assigned to two groups. One group will immediately start a 16-week SOAR program, while the second will wait for 9-weeks before starting an 8-week SOAR program. Trained physiotherapists will deliver the SOAR program with videoconferencing. The study hypothesis is that participating in the 8-Week SOAR program will improve the knee muscle strength, physical activity levels, knee-related self-efficacy and knee-related quality of life in people discharged from regular healthcare after a sports knee injury. The findings will help researchers understand the ideal length of the program for a future clinical trial in real-world settings.

Purpose: The purpose of this study is to evaluate a novel, virtually delivered, PT-guided, knee health program (Stop OsteoARthritis - SOAR) for people who have been discharged from regular healthcare after a sports knee injury. Objectives: The primary objective of the study is to assess the efficacy of an 8-week SOAR program to improve knee muscle strength measured by computerized dynamometry (primary outcome and daily average moderate to vigorous physical activity measured by Tri-axial Accelerometer (secondary outcome), self-reported knee-specific self-efficacy (secondary outcome), and self-reported knee-related quality of life (secondary outcome) in people discharged from regular care after sports knee trauma. Several exploratory outcomes will also be assessed to inform the design of a future clinical trial. A secondary objective of this study is to evaluate the feasibility of a protocol for a future full-scale clinical trial to assess the effectiveness and implementation of SOAR. Both SOAR program and study protocol implementation and practicality outcomes will be collected. A third objective of this study is to inform the optimal length of the SOAR program. A fourth, exploratory objective, of this study, is to explore the experiences of stakeholders (i.e., knee injury participants and physiotherapists) to inform future implementation. Research Design: This is a proof-of-concept, two-armed, open-label, randomized delayed control trial with embedded 1:1 interviews. In this design, randomization determines when the intervention is provided (immediate or 9-week delay). Consenting eligible knee injury participants will be randomly allocated in a 1:1 ratio to immediate intervention (experimental) or delayed intervention (control) groups using a computer-generated sequence of random numbers. Consenting eligible and physiotherapists will complete Brief Action Planning certification and SOAR training before delivering the SOAR program virtually to the knee injury participants. The immediate study group will be complete an 8-week (weeks 1-8) SOAR program (Knee Camp, home-based exercise-therapy and physical activity with tracking, weekly 1:1 PT counseling sessions, and optional weekly group-based exercise classes) followed by an additional 8 weeks (weeks 10-17) of home-based exercise-therapy and physical activity with tracking, weekly 1:1 PT counseling sessions, and optional weekly group-based exercise classes. In contrast, after a 9-week delay, the delayed study group will complete an 8-week (weeks 10-17) intervention (Knee Camp, home-based exercise-therapy and physical activity with tracking, weekly 1:1 PT counseling sessions, and optional weekly group-based exercise classes). Knee injury participant outcomes will be evaluated at baseline (T0), 9-weeks (T1-primary endpoint to assess efficacy), and 18-weeks (T2- endpoint to inform optimal intervention length). Physiotherapist participants will be evaluated prior to training, immediately after training, and after they have delivered the SOAR program to all knee injury participants that they have been assigned in the study. Statistical Analysis: Descriptive statistics will be calculated for all demographic variables, and observed differences (sex, prior injury, injury type, prior treatment, etc.) considered when interpreting findings. Randomization integrity will be monitored. Outcomes will be disaggregated by sex and gender, and mean differences between T0 and T1, and T1 and T2 described by the study group. Intention-to-treat analyses will be conducted. Generalized linear mixed-effects regression models for longitudinal data (95%CI), controlling for the blocking effect, will estimate the effect of an 8-week intervention (IG T1-T0 versus DG T1-T0, and DG T2-T1 versus T1-T0) and the delay (IG T1-T0 versus DG T2-T1) for the primary outcome (Figure 2). In addition, two exploratory analyses will be conducted. To inform the optimal intervention length for the future clinical trial, a longitudinal mixed-effects model will be used to examine the intervention effect at 16-week. This model will include the following fixed effects: 1) the randomization group indicator for baseline difference; 2) indicator variables for follow-up assessment time points (9-week and 18-week) to account for secular trend, and; 3) indicator variables for the lengths of time since intervention initiation (9-week or 18-week) to estimate effects after these time intervals. The model will also include participant-specific random effects to account for repeated measures. To inform the most meaningful muscle function outcome for the future clinical trial linear regression (95%CI) models, adjusted for age and sex, will be used to identify differences in the association between various aspects of knee extensor muscle function (torque, power, rate of force development), and composite self-reported knee symptoms and function score. Interview recordings with knee injury participants and physiotherapist participants will be transcribed verbatim and de-identified. Using a constant comparative approach data will be coded and categories developed by comparing and determining meaningful patterns across codes. High-order themes will illuminate the relationship between categories. Uniqueness in experience by gender will be explored and if identified, data will be reanalyzed in gender sub-groups. A detailed audit of analytic decisions will be kept.

Arthritis, Osteoarthritis, Arthritis Knee, Osteo Arthritis Knee, Knee Injuries, Anterior Cruciate Ligament Tear, Meniscus Tear

Randomized delayed control trial, Knee health, Knee injury, Sport injury, Knee muscle, Self-efficacy, Quality of life, Osteoarthritis

Participants with a past sport-related knee injury randomized to the 'immediate intervention' group will complete an 8-week (weeks 1-8) SOAR program (Knee Camp, home-based exercise-therapy and physical activity with tracking, weekly 1:1 physiotherapist counseling sessions, and optional weekly group-based exercise classes) followed by an additional 8 weeks (weeks 10-17) of home-based exercise-therapy and physical activity with tracking, weekly 1:1 PT counseling sessions, and optional weekly group-based exercise classes. Consented trained physiotherapists will deliver the SOAR program throughout the study period to one or more immediate SOAR group knee injury participants.

Participants with a past sport-related knee injury randomized to the 'delayed intervention' group will have a 9-week unstandardized delay before completing an 8-week SOAR program (weeks 10-17). During the delay (weeks 1-9) the delay comparison intervention will be unstandardized to reflect usual care in Canada. After the 9-week delay, these participants will complete an 8-week (weeks 10-17) SOAR program (Knee Camp, home-based exercise-therapy and physical activity with tracking, weekly 1:1 PT counseling sessions, and an optional weekly group-based exercise classes). Consented trained physiotherapists will deliver the SOAR program from week 10 to week 17 to one or more delayed SOAR group knee injury participants.

This is an 8-week, virtually delivered, exercise-based, knee health program delivered to knee injury participants by trained physiotherapists. The program has 3 components: Knee Camp: This includes an interactive education session about knee health, 1:1 knee exam, and 1:1 counseling session to identify Specific, Measurable, Attainable, Relevant, and Time-bound (SMART) weekly home-based exercise-therapy and physical activity goals, Participants are asked to wear Fitbit's® 24-hours/day. Weekly Home-based Exercise-Therapy and Physical Activity, with Tracking: At home, participants work to meet their exercise-therapy and physical activity goals. Exercises are tracked with an online bespoke form and activity, with a Fitbit. Weekly PT-guided Exercise-Therapy and Physical Activity Counseling Sessions: Each week participants will attend a 1:1 virtual physiotherapist counseling session to modify SMART goals and have the option to attend a group exercise class.

This is an 8-week, virtually delivered, exercise-based, knee health program delivered to knee injury participants by trained physiotherapists. The program has 3 components: Knee Camp: This includes an interactive education session about knee health, 1:1 knee exam, and 1:1 counseling session to identify Specific, Measurable, Attainable, Relevant, and Time-bound (SMART) weekly home-based exercise-therapy and physical activity goals, Participants are asked to wear Fitbit's® 24-hours/day. Weekly Home-based Exercise-Therapy and Physical Activity, with Tracking: At home, participants work to meet their exercise-therapy and physical activity goals. Exercises are tracked with an online bespoke form and activity, with a Fitbit. Weekly PT-guided Exercise-Therapy and Physical Activity Counseling Sessions: Each week participants will attend a 1:1 virtual physiotherapist counseling session to modify SMART goals and have the option to attend a group exercise class.

A computerized dynamometer (Biodex®) will be used to assess and calculate normalized peak concentric knee extension (quadriceps muscle) isokinetic torque (Nm/kg) at 90 degrees/seconds over 0-100 degrees of knee flexion. After a five-minute stationary cycling warm-up, participants will be seated with straps secured across their hips and chest. After three practice trials and a 30-second rest, participants will be instructed to straighten and bend their knee as hard as they can for three repetitions. The total time for this test is 10 minutes. Computerized dynamometry (Biodex®) is a reliable, valid, relevant, and recommended measure of muscle strength.

Change in Daily Average Moderate to Vigorous Physical Activity over 9-weeks (knee injury participants)

A small, lightweight hip worn wearable triaxial accelerometer (ActiGraph GT3X®) will be used to assess physical activity. Participants will be asked to wear this device (attached via an elastic belt around their waist), for a period of 7 consecutive days removing only for bathing/swimming activities. The average number of 10-minute moderate-to-vigorous physical activity bouts over the 7-day period will be calculated. Accelerometry is a valid measure of physical activity in youth and young adult populations.

A 19 item questionnaire (the Knee Self-efficacy Scale) will be used to measure self-reported knee-specific self-efficacy. Each item is scored on an 0-10-point Likert scale, with 0 indicating no knee-related self-efficacy and 10 indicating full knee-related self-efficacy. Individual item scores are summed and divided by 19 to produce a total score ranging from 0-10 (0 representing poor knee-related self-efficacy and 10 representing full knee-related self-efficacy). The total time for this questionnaire is 3 minutes. The Knee Self-efficacy Scale is a valid and reliable measure of knee-specific self-efficacy in individuals with a sport-related knee injury in the past five years.

A 5 item subscale of the Knee Injury and Osteoarthritis Outcome Score (KOOS) questionnaire will be used to measure self-reported knee-related quality of life. Each item is scored on an 0-10-point Likert scale, with 0 indicating no knee-related quality of life and 10 indicating full knee-related quality of life. Individual item scores are summed and transformed to a score out of 100 (0 representing poor knee-related quality of life and 100 representing full knee-related quality of life). The total time for this questionnaire is 3 minutes. The KOOS knee-related quality of life sub-scale is a valid and reliable patient-reported outcome measure across multiple patient populations, including at various timepoints after knee trauma

A computerized dynamometer (Biodex®) will be used to assess and calculate normalized peak concentric knee extension (quadriceps muscle) isokinetic torque (Nm/kg) at 90 degrees/seconds over 0-100 degrees of knee flexion. After a five-minute stationary cycling warm-up, participants will be seated with straps secured across their hips and chest. After three practice trials and a 30-second rest, participants will be instructed to bend and straighten their knee as hard and as fast as they can for three repetitions. The total time for this test is 10 minutes. Computerized dynamometry (Biodex®) is a reliable, valid, relevant, and recommended measure of muscle strength.

Change in Daily Average Moderate to Vigorous Physical Activity over 18-weeks (knee injury participants)

A small, lightweight hip worn wearable triaxial accelerometer (ActiGraph GT3X®) will be used to assess physical activity. Participants will be asked to wear this device (attached via an elastic belt around their waist), for a period of 7 consecutive days removing only for bathing/swimming activities. The average number of 10-minute moderate-to-vigorous physical activity bouts over the 7-day period will be calculated. Accelerometry is a valid measure of physical activity in youth and young adult populations.

A 19 item questionnaire (the Knee Self-efficacy Scale) will be used to measure self-reported knee-specific self-efficacy. Each item is scored on an 0-10-point Likert scale, with 0 indicating no knee-related self-efficacy and 10 indicating full knee-related self-efficacy. Individual item scores are summed and divided by 19 to produce a total score ranging from 0-10 (0 representing poor knee-related self-efficacy and 10 representing full knee-related self-efficacy). The total time for this questionnaire is 3 minutes. The Knee Self-efficacy Scale is a valid and reliable measure of knee-specific self-efficacy in individuals with a sport-related knee injury in the past five years.

A 5 item subscale of the Knee Injury and Osteoarthritis Outcome Score (KOOS) questionnaire will be used to measure self-reported knee-related quality of life. Each item is scored on an 0-10-point Likert scale, with 0 indicating no knee-related quality of life and 10 indicating full knee-related quality of life. Individual item scores are summed and transformed to a score out of 100 (0 representing poor knee-related quality of life and 100 representing full knee-related quality of life). The total time for this questionnaire is 3 minutes. The KOOS knee-related quality of life sub-scale is a valid and reliable patient-reported outcome measure across multiple patient populations, including at various timepoints after knee trauma

The 8 and 18 item symptom and pain subscales of the Knee Injury and Osteoarthritis Outcome Score (KOOS) questionnaire will be used to measure self-reported knee-related symptoms. Each item is scored on an 0-10-point Likert scale, with 0 indicating a high degree of symptoms and 10 indicating no symptoms. Individual item scores are summed and transformed to a score between 0 and 100, with higher scores indicating a better outcome (i.e., fewer knee-related symptoms). The total time for this questionnaire is 3 minutes. The KOOS knee-related symptoms sub-scale is a valid and reliable patient-reported outcome measure across multiple patient populations, including at various timepoints after knee trauma.

Change in Self-reported knee-related Sport and Recreation Function over 9-weeks (knee injury participants)

The 17 and 5 item function in daily living and function in sport and recreation subscales of the Knee Injury and Osteoarthritis Outcome Score (KOOS) questionnaire will be used to measure self-reported knee-related symptoms. Each item is scored on an 0-10-point Likert scale, with 0 indicating no knee-related sport and recreation function and 10 indicating full knee-related sport and recreation function. Individual item scores are summed and transformed to a score out of 100 (0 representing poor knee-related sport and recreation function and 100 representing full knee-related sport and recreation function). The total time for this questionnaire is 3 minutes. The KOOS knee-related sport and recreation function sub-scale is a valid and reliable patient-reported outcome measure across multiple patient populations, including at various timepoints after knee trauma.

The 3 item Patient Specific Functional Scale will be used to identify, quantify and assess changes in functional limitations that are most relevant to participants. This scale prompts participants to identify three activities important to them and rate their ability to perform each activity on a 10-point numerical rating scale. Individual scale scores are summed and transformed to a 0-100 scale with higher scores indicating better outcomes. The total time for this questionnaire is 3 minutes. The Patient-Specific Functional Scale is valid and reliable for use in persons with a knee injury.

The 4 item Godin Leisure Time Questionnaire will be used to measure self-reported physical activity. Using the number of 15-minute bouts of mild, moderate, and strenuous physical activity a participant engages in over a typical seven-day period weekly metabolic equivalents of physical activity are calculated. The total time for this questionnaire is 1 minute. The Godin Leisure Time Questionnaire has been validated to assess physical activity.

The 12 item Partner in Health Scale will be used to measure perceived self-care (active involvement to self-manage a chronic condition). Each item is scored on a 0-9 point Likert scale. Scores on individual items are summed to produce a total score ranging between 0 and 96, with 0 representing no perceived self-management and 96 representing full perceived self-management. The total time for this questionnaire is 3 minutes. The Partner in Health Scale is valid and reliable across numerous chronic conditions.

The 11 item Tampa Scale of Kinesiophobia will be used to measure self-reported fear of movement and re-injury. Each item is scored on a 0-4 point Likert-scale, with 0 indicating no fear of movement and 4 indicating greater fear of movement. The item scores are summed to produce a total score ranging between 0 and 44, with higher values indicating a higher degree of fear of movement. The total time for this questionnaire is 3 minutes. The Tampa Scale of Kinesiophobia has evidence of known-group validity (scores discriminated between athletes who returned and did not return to pre-injury sports participation level after knee trauma).

Change in Self-reported Perceived Social Support from family and friends over 9-weeks (knee injury participants)

The 12 item Multi-Dimensional Scale of Perceived Support will be used to measure perceived support from family, friends, and significant others. Each item is scored on a 0-7 point Likert scale, with 0 representing poor perceived support and 7 representing greater perceived support. Individual item scores are summed and divided by 12 to produce a total score ranging between 0 and 7 with higher scores indicating higher levels of perceived support. The total time for this questionnaire is 3 minutes. The Multi-Dimensional Scale of Perceived Support is reliable and valid across diverse general populations including adolescents.

Change in Self-reported Perceived Social Support from Sport and Recreation Community over 9-weeks (knee injury participants)

The 16 item Perceived Available Social Support Questionnaire will be used to assess perceived support from the sporting or recreational community. Each item is scored on a 0-4 point Likert scale, with 0 representing poor perceived support and 4 representing greater perceived support. Individual item scores are summed and divided by 16 to produce a total score ranging from 0 to 4, with higher scores indicating higher levels of perceived support. The total time for this questionnaire is 3 minutes. The Perceived Available Social Support Questionnaire is a valid and reliable measure of self-reported perceived support for sporting populations.

Change from baseline self-reported perceived social support from the sport and recreation community 9-weeks

A computerized dynamometer (Biodex®) will be used to assess and calculate normalized peak concentric knee flexor (hamstring muscles) isokinetic torque (Nm/kg) at 90 degrees/seconds over 0-100 degrees of knee flexion. After a five-minute stationary cycling warm-up, participants will be seated with straps secured across their hips and chest. After three practice trials and a 30-second rest, participants will be instructed to straighten and bend their knee as hard as they can for three repetitions. The total time for this test is 10 minutes (assessed in conjunction with normalized peak knee extension torque). Computerized dynamometry (Biodex®) is a reliable, valid, relevant, and recommended measure of muscle strength.

A computerized dynamometer (Biodex®) will be used to assess and calculate knee extension power (Watts). After completing the protocol for normalized peak concentric knee extension and flexion torque the participants' knee joint will be fixed in 60 degrees of sagittal plane flexion. After three practice trials and a 30-second rest, participants will be instructed to straighten their knee as hard and as fast as they can for five seconds. This will be repeated five times with a 30-second rest period between each repetition. The total time for this test is 10 minutes. Computerized dynamometry (Biodex®) is a reliable, valid, relevant, and recommended measure of muscle power.

A computerized dynamometer (Biodex®) will be used to assess and calculate knee flexion power (Watts). After completing the protocol for normalized peak concentric knee extension and flexion torque the participants' knee joint will be fixed in 60 degrees of sagittal plane flexion. After three practice trials and a 30-second rest, participants will be instructed to bend their knee as hard and as fast as they can for five seconds. This will be repeated five times with a 30-second rest period between each repetition. The total time for this test is 10 minutes. Computerized dynamometry (Biodex®) is a reliable, valid, relevant, and recommended measure of muscle power.

Single leg hop function will be measured using the 6-meter timed hop test. Participants are asked to hop forward with the goal of covering a 6-meter distance as quickly as they can. Two practice trials will be completed on each limb, starting with the unaffected side to familiarize participants with the task. Participants will then complete two test trials on each limb, starting again with the unaffected side. The time (seconds) required to hop the 6-m distance will be recorded. This protocol will take 10 minutes. The 6-m timed hop is clinically applicable and reliable.

Fat mass index (kg/m2) will be measured with Bioelectrical Impedance (Tanita Body Composition Analyzer, Model TBF-300A, Tanita Inc., USA). Participants will stand barefoot on the bioelectrical impedance platform during which the resistance to the flow of this single, high frequency alternating electrical current (500 A at 50 kHz) will be measured. Bioelectrical Impedance is a feasible method for assessing and tracking body composition in clinical settings and has been shown to be valid and reliable in child, youth, and adult populations. This test will take 5 minutes to complete. The device will be calibrated prior to each scan (according to the manufacturer's protocol).

At the end of the study, semi-structured 1:1 interviews will be conducted with a sub-sample of 15-20 knee injury participants. Using an inductive approach and interview guide, participants will be asked open-ended queries about their experiences with the intervention (SOAR program). Interviews will last approximately 45 minutes.

A bespoke online survey will assess physiotherapists' overall confidence to deliver the intervention (SOAR program) including Brief Action Planning, SMART goal setting, and virtual physiotherapy delivery. Participants will be asked to rate their overall confidence on a 0-10 point numerical rating scale where 0 represents no confidence and 10 represents full confidence. The score will be transformed to a score between 0 and100, with higher scores indicating higher confidence. The survey will take 3 minutes to complete.

Inclusion Criteria: Knee Injury Participant Inclusion Criteria: 16-35 years of age Currently live in British Columbia, Canada Experienced a sport-related intra-articular knee injury (i.e., clinical diagnosis of ligament, meniscal, or other intra-articular tibio- or patello-femoral trauma) that required both medical consultation (i.e., physician, physiotherapist, chiropractor, surgeon, or athletic therapist) and disrupted regular sports participation (missed at least one training session or competition) 12-36 months previously.18 Are currently not receiving ongoing health care related to the past knee injury and have no scheduled surgical procedures (any part of the body) that would interfere with exercise during the study. Have daily access to an email address and a computer with internet Are willing to wear an activity tracker during the study Physiotherapist Participant Inclusion Criteria: Registered physiotherapist Able to communicate in English Have an email address and daily access to a computer with internet service Exclusion Criteria: Knee Injury Participant Exclusion Criteria: Inability to communicate in English Previous physician diagnosis of index knee osteoarthritis Inflammatory arthritis or systemic condition Lower limb injury, surgery, or intra-articular injection in the past 6-months Current pregnancy Have a pacemaker or other internal medical device Physiotherapist Participant Exclusion Criteria: Do not hold a license to practice physiotherapy Unable to communicate in English Do not have an email address or daily access to a computer with internet service

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