Exercise Intervention Targeting Hip Strengthening Compared to Usual Care in Patients Undergoing Revision Hip Replacement

Study Overview
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Brief Summary
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There is sparse evidence on revision total hip replacement (THR), regarding the effectiveness on pain and function, and no consensus exists on optimal rehabilitation after revision THR. Further, patients undergoing revision THR achieve worse clinical outcomes on hip pain and function compared to patients undergoing primary THR. The primary aim of this randomized controlled trial is to compare the clinical effectiveness of a partly tele-delivered exercise intervention targeting hip strengthening with the standard community-based rehabilitation (usual care) in patients undergoing revision THR. The investigators will test the hypothesis that the exercise intervention targeting hip strengthening is superior to standard community-based rehabilitation in improving physical function measured with the 30-second Chair Stand Test at 16-week follow-up.

Detailed Description
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There is sparse evidence on revision total hip replacement (THR), regarding the effectiveness on pain and function, and no consensus exists on optimal rehabilitation after revision THR. Revision THR is one of the more technically challenging orthopedic surgeries and patients undergoing revision THR report improvements in pain and function. Nevertheless, patients undergoing revision THR achieve worse clinical outcomes on hip pain and function compared to patients undergoing primary THR. This calls for research exploring different rehabilitation approaches, in order to improve clinical outcomes for patients after revision THR. This study aims to compare the clinical effectiveness of a partly tele-delivered exercise intervention targeting hip strengthening with the standard community-based rehabilitation (usual care) in patients undergoing revision THR. This randomized, controlled, assessor-blinded trial is a multicenter trial involving hospitals and municipality rehabilitation centers across Denmark. Eligible patients undergoing revision THR will be randomized into two groups: A partly remotely-delivered hip strengthening rehabilitation intervention (strength group) or usual care (control group). The exercise intervention targeting hip strengthening will partly follow the Neuromuscular Exercise (NEMEX) program as described by Eva Ageberg et al., and the intervention is further modified based on expert opinion from patients' experience with rehabilitation from a prior qualitative study. Usual care consists of rehabilitation in the municipalities, where it is up to the individual physiotherapist and the municipality to organize the rehabilitation, which is why both type, content, and duration may vary. The primary outcome will be change in functional performance measured by the 30-second Chair Stand Test. Outcomes will be measured at baseline, after 16 weeks of intervention, and at 12-month follow-up. The investigators hypothesize that the exercise intervention targeting hip strengthening is superior to usual care in improving physical function measured with the 30-second Chair Stand Test at 16-week follow-up.

Official Title
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Effect of an Exercise Intervention Targeting Hip Strengthening in Patients Undergoing Revision Total Hip Replacement - a Multicenter, Randomized Controlled Trial (The Strong Hip Trial)

Conditions
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Revision Total Hip Arthroplasty

Intervention / Treatment
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* Other: Exercise Intervention Targeting Hip Strengthening
* Other: Usual Care


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing first revision THR Age ≥ 18 years Motivated to participate in an exercise program for 16 weeks Provided informed consent to participate Patients who has the cup and/or stem replaced or a combination of liner and caput replaced Patients who can be baseline tested (chair stand test, stair climb test, 40m walking test) Exclusion Criteria: Dependency of wheelchair Preplanned other lower limb surgery within 12 months Body Mass Index (BMI) score > 40 Currently undergoing cancer treatment, e.g. chemo-, immuno-, or radiotherapy. Comorbidities that prevent exercise Inadequacy in written and spoken Danish Mentally unable to participate

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Strength group<br>Group 1 | Other: Exercise Intervention Targeting Hip Strengthening<br>* An initial 16-week exercise intervention of 45 minutes of training 3 times a week in the patient's own home or at a rehabilitation center. Patients will be instructed by a physiotherapist during the first 3 sessions, in order to be able to perform the exercises at home. Subsequently, there are physiotherapist-supervised sessions once every second week. The delivery of the supervised sessions is based on the patient's preferences, either by physical attendance or remotely in the patient's home. The intervention will consist of 4 exercises adapted from the NEMEX program targeting lower extremity muscle strength, stability, postural function, and postural orientation. Progression is made when an exercise is performed with good sensorimotor control and good performance quality and with minimal exertion and adequate movement control. Progression is primarily provided by 3 levels of difficulty and secondly by varying the number of repetitions or where possible, by increasing the weight load.<br>|
| Active Comparator: Control group<br>Group 2 | Other: Usual Care<br>* The intervention will consist of a rehabilitation intervention corresponding to standard care in the participating municipalities (i.e. content and duration of intervention). The intervention will be delivered individually or as group training, based on a clinical assessment of the individual patients' needs. The intervention can be supported by home-based exercises following instruction from a physiotherapist, supplemented by the provision of written information or access to a virtual training program. The intervention occurs in either the rehabilitation center's gym or the patient's home. The training sessions may consist of some of the following parameters: Strength training, stretching, functional training e.g. walking and stair climbing, stability training, balance training, endurance training, and gait correction.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in functional performance measured by the 30-seconds chair stand test | The 30-second chair stand test is a valid and reliable measure of lower-extremity muscle strength evaluating sit-to-stand function, which is limited in people undergoing hip replacement. | Measured at baseline, 16-week, and 12-month follow-up. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in the Hip disability and Osteoarthritis Outcome Score (HOOS) pain subscale | The HOOS pain subscale is a 10-item patient-reported outcome measure designed to assess hip pain in patients with hip osteoarthritis. The total score ranges from 0 to 100, with higher scores indicating better pain status. | Measured at baseline, 16-week, and 12-month follow-up. | 
| Change in the HOOS symptoms subscale | The HOOS symptom subscale is a five-item patient-reported outcome measure designed to assess other hip symptoms in patients with hip osteoarthritis. The total score ranges from 0 to 100, with higher scores indicating better symptom status. | Measured at baseline, 16-week, and 12-month follow-up. | 
| Change in the HOOS activities of daily living (ADL) function subscale | The HOOS ADL function subscale is a 17-item patient-reported outcome measure designed to assess ADL function in patients with hip osteoarthritis. The total score ranges from 0 to 100, with higher scores indicating better ADL function status. | Measured at baseline, 16-week, and 12-month follow-up. | 
| Change in the HOOS quality-of-life subscale | The HOOS quality-of-life subscale is a four-item patient-reported outcome measure designed to assess hip-related quality-of-life in patients with hip osteoarthritis. The total score ranges from 0 to 100, with higher scores indicating better quality-of-life status. | Measured at baseline, 16-week, and 12-month follow-up. | 
| Change in the HOOS sports and recreation subscale | The HOOS sports and recreation subscale is a four-item patient-reported outcome measure designed to assess sports and recreation function in patients with hip osteoarthritis. The total score ranges from 0 to 100, with higher scores indicating better sports and recreation status. | Measured at baseline, 16-week, and 12-month follow-up. | 
| Change in 40m Fast-Paced Walk Test (40m-FPWT) | The 40m-FPWT is a physical function test designed to measure the ability to walk quickly over short distances and is measured as the time it takes to complete a 40 m course at a fast walking pace. | Measured at baseline, 16-week, and 12-month follow-up. | 
| Change in 9-step Timed Stair Climb Test (9-step TSCT) | The 9-step TSCT is a physical function test designed to measure lower body strength and balance as well as ascending and descending stair activity and is measured as the time it takes to ascend and descend a 9-step stair. | Measured at baseline, 16-week, and 12-month follow-up. | 
| Change in leg extension muscle power (watt/kg body weight) | The Nottingham Power Rig (NPR) is used to measure leg extensor muscle power. The NPR measures the power output in total watt and watt pr. bodyweight in kilograms from a seated push on a flat pedal which is transmitted by a lever and chain to spin a flywheel. The NPR is a safe and reliable method to measure explosive knee extensor muscle power and has been validated as a clinically important measure of muscle function in elderly individuals. | Measured at baseline, 16-week, and 12-month follow-up. | 
| Global Perceived Effect (GPE) | The GPE will be used as a measure of patient-rated recovery and will be assessed for three domains; pain, activities of daily living, and quality of life rated on a 7-point Likert scale ranging from 'very bad' (worst) to 'very good' (best) | Measured at 16-week and 12-month follow-up. | 
| AE (Adverse Events) & Serious Adverse Events (SAE) | Continuous registration of health issues and injuries. The events will be monitored by the physiotherapists supervising the exercise sessions. Further, patients will be asked at 4- and 12-month follow-ups about potential AE and SAE using open-probe questions. | Registered throughout the 12-month study period. | 
| Adherence to the 16-week intervention | High adherence is defined as attendance in ≥75% of the exercise sessions. | Registered throughout the 16-week initial intervention. | 
| Drop-outs | Number of drop-out from the interventions. | Registered throughout the 12-month study period. |