First-line Treatment for Femoroacetabular Impingement Syndrome

There is sparse evidence on the effectiveness of first-line treatment in patients with femoroacetabular impingement syndrome (FAIS) regarding clinical- and cost-effectiveness.

The goal of this randomized controlled trial is to compare the clinical effectiveness and cost-effectiveness of a supervised strength exercise intervention to usual first-line care in patients with FAIS.

The main hypothesis it aims to investigate are:

1. 6-months of supervised strength exercise intervention is superior (i.e., at least 6 points, on a scale from 0-100) to usual care in improving hip related quality of life in patients with FAIS at the end of intervention.
2. 6-months of supervised strength exercise intervention is cost-effective compared to usual first-line care at 12-month follow-up in patients with FAIS.
3. High exercise adherence and dosage will be superior to low exercise adherence and dosage in mediating clinical effectiveness in patients with FAIS.

There is sparse evidence on the effectiveness of first-line treatment in patients with femoroacetabular impingement syndrome (FAIS) regarding clinical- and cost-effectiveness.

The Better Hip trial is a multicenter, stratified (by hospital site), randomized (allocation 1:1), controlled, assessor blinded, superiority trial conducted in Denmark (Aarhus, Horsens, Aalborg, and Odense) and Australia (Melbourne). Eligible patients will either be randomized to a supervised strength exercise intervention or to usual care. The primary outcome will be hip-related quality of life measured at end of intervention (6 months) with the iHOT-33. A health economic evaluation will assess the difference in cost-effectiveness between groups from baseline to 12 months. Secondary outcomes will be measured at baseline, 3-, 6- and 12- months after initiating the intervention for patient reported outcome measures (PROMs), and at baseline and 6-months for objective outcome measures obtained at clinical assessments.

This trial aims to investigate the clinical and cost-effectiveness of a supervised strength exercise intervention compared to usual care as first-line treatment in patients with FAIS. A secondary aim is to explore how exercise adherence and dosage of a supervised strength exercise intervention mediates outcomes.

The investigators hypothesis that;

1. 6-months of supervised strength exercise intervention is superior (i.e., at least 6 points, on a scale from 0-100) to usual care in improving hip related quality of life in patients with FAIS at the end of intervention.
2. 6-months of supervised strength exercise intervention is cost-effective compared to usual first-line care at 12-month follow-up in patients with FAIS.
3. High exercise adherence and dosage will be superior to low exercise adherence and dosage in mediating clinical effectiveness in patients with FAIS.

A full trial protocol will be published and made publicly available prior to analysis for the primary paper. All primary and secondary outcomes will be analysed with the intention-to-treat principle. Supplementary to the intention-to-treat analysis a per protocol analysis will be conducted. Between-group differences will be analyzed using a linear mixed effect model for continuous outcomes and a logistical mixed effect model for binary outcome variables. Intervention group, recruitment site and time will be included as fixed effects and patients will be included as a random effect. Incremental cost-effectiveness ratios (ICER) will be calculated by dividing the difference in costs by the difference in effects (quality-adjusted life years for cost-utility and iHOT-33 for cost-effectiveness)

Eligibility Criteria:
Inclusion Criteria:

1. Activity- or position-related pain lasting ≥ 3 months
2. Positive Flexion-Adduction-Internal rotation (FADIR) test
3. Cam-type FAIS; x-ray alpha angle =\> 60 degrees
4. Pincer-type FAIS; lateral center edge angle \> 39 degrees or crossover-sign
5. Mixed-type FAIS; a combination of cam- and pincer-type impingement
6. Motivated to exercise 2 times a week for 6 months
7. 18-50 years old
8. Body Mass Index (BMI) score \< 35

Exclusion Criteria:

1. Physiotherapist-led strengthening exercises targeting the hip for at least 3 months for ≥ 6 sessions prior to inclusion
2. Previous hip surgery or other major hip injury in index hip (i.e., hip arthroscopy, fracture, calves perthes, necrosis or luxation).
3. Evidence of pre-existing osteoarthritis, defined as Tönnis grade ≥ 2 or Kellgreen-Lawrence ≥ 2
4. Evidence of pre-existing osteoarthritis, defined as lateral joint space width ≥ 3 mm (measured at the lateral sourcil).
5. Hip dysplasia, defined as a Center-Edge-angle (CE-angle) ≤ 25° and an acetabular index \> 10°
6. Comorbidities or other problems considered to affect hip function and participation in exercise
7. Unable to communicate in the respective languages of the participating countries