An interventional study of PAO and Usual care after PAO in Hip Dysplasia, sponsored by University of Aarhus. Completed at 3 sites in 2 countries. Open to participants aged 18 Years to 40 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2026-05-29.
Sponsored by University of Aarhus · Not applicable, Interventional, and Treatment
The primary aim of this study is to examine if Periacetabular Osteotomy (PAO) followed by 4 months of usual care followed by 8 months of progressive resistance training (PRT) is superior to 12 months of a PRT intervention in patients with hip dysplasia eligible for PAO in terms of self-reported pain on the HAGOS questionnaire. Secondary aims are to investigate changes in patient-reported symptoms, physical function in daily living, physical function in sport and recreation, hip and/or groin-related quality of life, generic health status, functional performance, muscle strength, physical activity and adverse events between PAO followed by usual care+PRT compared to PRT only. We hypothesise that in patients with hip dysplasia, PAO followed by usual care+PRT, results in significantly less pain at 12 months follow-up, compared to PRT only.
Group 1 (PAO+usual+PRT):
PAO will be performed as the trans-sartorial approach or the anterior pelvic approach. Patients commence post-operative rehabilitation as usual and follow the rehabilitation program guided by a physiotherapist specialized in hip problems until 4 months after the operation. 4 months postoperative the patients complete usual care and continue with the same PRT intervention program as the PRT group, with 4 months of supervised sessions (see description below).
Group 2 (PRT):
The PRT group receives 4 months of supervised PRT 2 times per week. A physiotherapist or students will supervise all training sessions the first 4 weeks. The following 4 weeks, 6 out of 8 training sessions are supervised and from week 9-16, half of the training sessions (8 out of 16) are supervised. After these 4 months (16 weeks), patients receive a free membership to a fitness center near their home address and are encouraged to train on their own 2 times per week until 12 months follow-up with one supervised session per month. The PRT program involves 10-min of warm up followed by 50-min of bilateral resistance exercises including sets of loaded squats, hip extension, hip flexion, and hip abduction. The absolute training load will be individually adjusted on a set-by-set basis, using the plus two principle (if the patient is able to perform two or more repetitions than required, the load is increased). Hip related pain levels up to 5 on the VAS is considered acceptable during exercise.
The study is a multicentre randomised controlled and assessor blinded trial. Primary endpoint will be 12 months after initiation of surgical/non-surgical treatment. Secondary endpoints will be measured at 4 months after the start of the treatment (surgical/non-surgical). In addition, 5-year and 10-year follow-up with questionnaires is planned.
107 studies on the registry are indexed under Hip Dislocation; 36 are open to participants now.
This study's enrollment of 69 is below the median of 86 across 64 interventional studies indexed under Hip Dislocation.
Browse Hip Dislocation studies →University of Aarhus is the lead sponsor of 1,300 studies on the registry; 189 are open to participants now.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
BMI (body mass index)
Weight in kilograms divided by height in metres squared. Example: 70 kg and 1.75 m gives 70 ÷ (1.75 × 1.75) ≈ 22.9.
What counts as overweight or obesity differs between countries (some use lower cut-offs), so go by the range the study states.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
PAO+usual+PRT
Procedure: PAO · Other: Usual care after PAO · Other: PRT
PRT
Other: PRT
PAO will be performed as the trans-sartorial approach or the anterior pelvic approach.
Patients commence post-operative rehabilitation as usual and follow the rehabilitation program guided by a physiotherapist specialized in hip problems until 4 months after the operation.
4 months of partly supervised progressive resistance training 2 times per week. After these 4 months (16 weeks), patients receive a free membership to a fitness center near their home address and are encouraged to train on their own 2 times per week until 12 months follow-up with one supervised session per month. The PRT program involves 10-min of warm up followed by 50-min of bilateral resistance exercises including sets of squats, hip extension, hip flexion, and hip abduction.
Change in pain related to hip function, between baseline and 12 months follow-up
The pain subscale of the patient reported questionnaire Copenhagen Hip and Groin Outcome Score (HAGOS), were the total score ranges from 0 (worst) to 100 (best).
Time frame: Measured at baseline, 4 month follow-up and 12 month follow-up
Change in self-reported hip function
The subscales; Symptoms, Physical function in daily living, Physical function in Sport and Recreation, Participation in Physical Activities and hip and/or groin-related Quality of Life of the patient reported questionnaire Copenhagen Hip and Groin Outcome Score (HAGOS), where the total score ranges from 0 (worst) to 100 (best).
Time frame: Measured at baseline, 4 month follow-up and 12 month follow-up
Change in hip function
Single leg hop for distance is a test that measure functional performance requiring both strength, power and balance. The distance from start to landing is measured in cm. and height adjusted by dividing the distance of the hop with the height of the patient.
Time frame: Measured at baseline, 4 month follow-up and 12 month follow-up
Change in balance function
The Y balance test require strength, flexibility, neuromuscular control, stability, range of movement, balance and proprioception. These elements are tested and the maximal reach distance is recorded for each direction (anterior, posteromedial and posteroladeral). The composite reach is calculated and normalized to limb length for analysis of the overall performance on the test.
Time frame: Measured at baseline, 4 month follow-up and 12 month follow-up
Number of patients with adverse events and serious adverse events after PAO
Adverse events: * Haematoma * Delayed wound closure * Dysaethesia of lateral femoral cutaneous nerve * Malpositioning; retroversion or insufficient reorientation. Insufficient reorientation (coverage) - optimal is CE angle 30-40 degrees. AI angle 0-10 degrees. * Heterotopic ossifications (Brooker I and II) * Urinary tract infections * Infection not requiring surgical revision Serious adverse events: * Avascular necrosis of the femoral head or acetabulum * Nerve palsy * Major bleeding (administration of more than 5 blood units intra- and postoperatively) * Peroneal and femoral neurapraxia * Deep vein thrombosis * Pulmonary embolism * Stress fracture of ischial bone and posterior column * Intraarticular osteotomy * Heterotopic ossifications (Brooker III and IV) * Infection requiring surgical revision * Loss of fixation/loss of reorientation * Delayed or non-union of pubic, ischial or iliac bone
Time frame: Reported within 12 months after surgery
Change in usage of painkillers
Usage of painkillers (yes/no), including type of painkillers (Paracetamol, NSAID, Morfin/opiods and/other type of medicine)
Time frame: Measured at baseline, 4 month follow-up and 12 month follow-up
Change in self-reported pain
Pain reported by the Visual Analogue Scale (VAS). A scale where pain is marked from 0-100, and 0 is no pain and 100 is worst imaginable pain.
Time frame: Measured at baseline, 4 month follow-up and 12 month follow-up
Change in hip awareness
Hip awareness is measured with the Forgotten Joint Score questionnaire (FJS), where each patient completes the 12 questions regarding awareness of their affected hip. Each question is answered with one of the following options; never, almost never, seldom, sometimes and mostly, corresponding to a score of 1-5. The sum of the scores will be converted into a score between 0-100. A high score will indicate lack of awareness and a low score will indicate great awareness of the affected hip.
Time frame: Measured at baseline, 4 month follow-up and 12 month follow-up
Change in muscle strength
Muscle strength in hip-abduction, hip-flexion and hip-extension is measured isometrically, with a dynamometer.
Time frame: Measured at baseline, 4 month follow-up and 12 month follow-up
Change in physical activity
Tri-axial accelerometer
Time frame: Measured at baseline and 12 month follow-up
Change in patient-reported health
Change in patient-reported health will be measured with the EuroQol Group 5-dimension patient-reported questionnaire (EQ-5D-5L), where each dimension has five response levels; ranging from no problems to extreme problems (level 1 to level 5). The scores will be combined, using one level from each dimension, ranging from 11111 (best health) to 55555 (worst health). The instrument also includes a visual analogue scale (VAS) where self-perceived health is scored on a 0 to 100 mm scale representing "the worst health you can imagine" and "the best health you can imagine".
Time frame: Measured at baseline, 4 month follow-up and 12 month follow-up
PDFs hosted by the registry, ClinicalTrials.gov.
Plan to share: Yes — Aarhus University Hospital is responsible for handling all personal data provided by both sites in accordance to the Clinical Trial Agreement and the EU General Data Protection Regulation (GDPR).
Supporting information: Study protocol, Statistical analysis plan, Informed consent form
Time frame: End of study and 5 years ahead
Access criteria: Oslo University Hospital agree that information directly related to the protocol and trial, including data, material, Intellectual Property and results generated from the trial shall be the property of Aarhus University Hospital, and shall be treated in strict confidence, and shall not be disclosed to any third party, or use for its benefit or the benefit of any third party, without the prior written consent of Aarhus University Hospital, except for data that is (i) publicly known or available from other sources who are not under a confidentially obligation to the other party; (li) has been made available by the other party without confidentiality obligation; or (iii) is independently developed or otherwise already known by or available to the other party without a confidentiality obligation; or (iv) is already required disclosed by law.
Ran from Jul 2019 to primary completion in Sep 2025, 74 months.
Of 32 interventional studies with no phase under Hip Dislocation, half reached primary completion within 45 months of starting (the median), counting those still running; a quarter within 18. This study's 74 months is above that.
How these figures are worked out, and which studies are left out of them.
This study is completed, as verified in Oct 2025. You cannot join it, but the record below documents what was studied.
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