Progressive Resistance Training Versus Total Hip Arthroplasty in Patients With Hip Osteoarthritis

The OHS is a 12-item patient-reported outcome measure designed to assess hip function and pain within the last four weeks among patients suffering from hip osteoarthritis in one score. The total score ranges from 0 to 48, with higher scores indicating better disease status.

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.

The HOOS pain 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 symptoms status.

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.

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.

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.

The UCLA Activity Score is a single-item patient-reported outcome measure designed to assess physical activity level. The score ranges from 1 to 10, with higher scores indicating greater physical activity level.

The 40m-FPWT is a physical function test designed to assess short distance maximum walking speed (meters/second).

The 30s-CST is a physical function test designed to assess sit-to-stand function (number of repetitions).

SAE according to the International Conference on Harmonisation-Good Clinical Practice (ICH-GCP) guidelines will be collected from The Danish National Patient Registry and medical record review conducted at the 6 months follow-up. Furthermore, a short patient-reported questionnaire at the 3 and 6 months follow-up will be used to ensure that all SAE are recorded.

The VAS pain is a single-item patient-reported outcome measure used to assess mean hip pain intensity at rest, and main hip pain intensity activity during the previous 24 hours. The total scale ranges from 0 (no pain) to 100 (worst pain imaginable).

The EQ-5D-5L is a five-item patient-reported outcome measure designed to assess generic health-related quality-of-life. The total score of the descriptive index and EQ-VAS ranges from -0.624 (worst) to 1.000 (best) and 0 (worst imaginable health) to 100 (best imaginable health), respectively. This will also allow for a later cost-utility analysis.

Medicine consumption will be assessed with the following question: "Have you been taking pain medication within the last week?" on a dichotomous scale (yes/no). Patients answering "yes" will be asked to provide type of medication on a categorical scale (Paracetamol, NSAID, morphine/opioids, Gabapentin, and other), frequency on 6-point Likert-scale ranging from "1 time a week" to "4 times a day or above", and asked "Have you primarily been taking pain medication due to your hip?" rated on a dichotomous scale (yes/no). Patients responding "no" to the latter question will be asked "If no, have you been taking pain medication due to other known diseases or disorders?" rated on on a dichotomous scale (yes/no).

The GPE of the interventions will be assessed for seven domains, including overall hip problems, hip pain, hip symptoms, ADL function, sports and recreation, hip-related quality-of-life, and physical activity on a 15-point Likert scale ranging from "a very great deal worse" (worst) to "a very great deal better" (best).

PASS will be assessed with the following question: "When you think of your hip function, will you consider your current condition as satisfying?" By hip function, you should take into account your activities of daily living, sport and recreational activities, your hip pain and other symptoms and your quality-of-life on a dichotomous scale (yes/no).

Patient-reported treatment failure will be assessed only by patients answering "no" to PASS with the following question: "Would you consider your current state as being so unsatisfactory that you think the treatment has failed?" on a dichotomous scale (yes/no).

Physical activity will be recorded with a tri-axial accelerometer (AX3, Axivity, Ltd., Newcastle, UK) mounted on the lateral thigh during a 7 day period. Data will be post-processed using a custom designed algorithm (MATLAB, Mathworks, Natick, MA, USA).

Isometric muscle strength of the index hip will be recorded for hip extension, flexion, and abduction with a handheld dynamometer (Commander Echo Wireless Console and Muscle Tester, JTECH Medical, Salt Lake City, Utah, USA) and reported as Newton meters per kilogram of the bodyweight (Nm/kg).

Number of total hip arthroplasty surgeries performed in the PRT group will be registered through a medical record review.

In the PRT group, the number of PRT sessions participated in by the patient will be registered by the supervising physiotherapist. High compliance will be defined as participation in ≥75% of the training sessions corresponding to 18 out of 24 sessions; moderate compliance as participation in 50-74% of the sessions; and poor compliance as participation in <50% of the sessions.

Training load of each exercise in the PRT group will be registered by the supervising physiotherapist and reported as kilogram (kg).

Following the 12-week supervised PRT program, adherence to three-months of optional unsupervised PRT will be measured by a patient-reported questionnaire.

Participation in postoperative supervised exercise in the THA group will be assessed using a patient-reported questionnaire.

Other treatments related to the index hip will be assessed using a patient-reported questionnaire.