An interventional study of PAO with hip arthroscopy and PAO without hip arthroscopy in Hip Dysplasia, sponsored by Ottawa Hospital Research Institute. Recruiting at 7 sites in 2 countries. Open to participants aged 16 Years to 50 Years. Per ClinicalTrials.gov, last updated 2025-12-30.
Sponsored by Ottawa Hospital Research Institute · Not applicable, Interventional, and Treatment
At present, it is not clear whether performing a hip arthroscopy at the same time as a PAO improves patient outcomes after surgery compared to a PAO alone.
This research project will randomize patients to receive either a PAO alone, or a PAO and a hip arthroscopy at the same time.
Hip dysplasia is a developmental abnormality of the acetabulum (hip socket) that causes abnormal stresses inside the hip joint and leads to painful arthritis at a young age. Many patients develop painful symptoms in their hip before advanced arthritis occurs.
The periacetabular osteotomy (PAO) is a surgical procedure that reorients the acetabulum to reduce the stresses inside the hip joint. The PAO is very effective at improving symptoms and quality of life. However, some patients may have residual symptoms.
Frequently, people with hip dysplasia will have an MRI done before their surgery, which helps to identify other the abnormalities inside their hip joint (e.g., labral tears). These abnormalities inside the joint cannot easily be addressed through PAO alone, however they can be addressed with hip arthroscopy. Hip arthroscopy is a separate minimally invasive surgical procedure that allows the surgeon to access the inside of the hip joint with a small camera and address any abnormalities.
At present, it is not clear whether performing a hip arthroscopy at the same time as a PAO improves patient outcomes after surgery compared to a PAO alone.
This research project will randomize patients to receive either a PAO alone, or a PAO and a hip arthroscopy at the same time. Patients will be followed for 2 years after surgery. Symptomatic differences between the two patient groups will be assessed to determine added benefit of the hip arthroscopy.
Exclusion Criteria:
Patient's in the "Scope PAO" group have been diagnosed with hip dysplasia and a decision has been made between the patient and the surgeon that the best way to treat the hip problems is with surgery. Patient's in the "Scope-PAO" group have been randomized to receive a periacetabular osteotomy with a hip arthroscopy.
Procedure: PAO with hip arthroscopy
Patient's in the "PAO-only" group have been diagnosed with hip dysplasia and a decision has been made between the patient and the surgeon that the best way to treat the hip problems is with surgery. Patient's in the "PAO-only" group have been randomized to receive a periacetabular osteotomy only.
Procedure: PAO without hip arthroscopy
Participants who are randomized to the Scope-PAO group will receive central compartment hip arthroscopy in addition to the PAO.
Participants who are randomized to the "PAO-only" group will receive a Bernese Periacetabular Osteotomy (PAO) for treatment of hip dysplasia.
iHOT-33
Patient-reported quality of life will be the primary outcome used for comparison between the two treatment groups as measured by the International Hip Outcome Tool (iHOT-33). The iHOT-33 is a validated, self-administered quality of life assessment tool for young, active patients with hip symptoms.
Time frame: 24 months
HOOS
Hip-specific symptoms and functional impairment will be compared using the Hip Disability and Osteoarthritis Outcome Score (HOOS). This 40-item patient reported outcome tool has been validated for use in patients with and without hip osteoarthritis and has shown good responsiveness, reliability and reproducibility in this patient population.
Time frame: before surgery, 6 months, 12 months, 24 months after surgery
PROMIS Global 10
Global Health assessment will be compared using the PROMIS Global 10 Score. This 10-item tool assesses general domains of health related quality of life in the domains of physical, mental, and social well-being.
Time frame: before surgery, 6 months, 12 months, 24 months after surgery
Operative time
Total operative time is expected to be longer in the "Scope-PAO" treatment group, however the average increase in time will be valuable information for future research assessing cost-effectiveness of this treatment strategy. Total operative time will be measured from the time the patient enters the operating room to the time the patient is ready for transfer to post-anesthetic care unit (PACU). This time interval represents the best assessment of the overall time cost to the health care system associated with the surgical procedure while avoiding confounding due to delays in transfer to PACU.
Time frame: intra-operative
Hospital Length of Stay
Length of stay, measured in days, will be assessed from date of admission to date of discharge up to one month.
Time frame: up to one month
Adverse Events
Adverse events will be assessed prospectively at the first and second post-operative visits using Sink et al.'s classification system that grades the complications based on required treatment and long-term morbidity.
Time frame: 2-4 weeks and 3 months after surgery
Cost-Effectiveness
The cost-effectiveness of the two study groups will be assessed prospectively using the Work Productivity and Activity Impairment Questionnaire. This 6-item validated questionnaire quantifies work impairments. Four scores are derived: percentage of absenteeism, percentage of presenteeism (reduced productivity while at work), an overall work impairment score that combines absenteeism and presenteeism and percentage of impairment in activities performed outside of work. Greater scores indicate greater impairment.
Time frame: 6 months, 12 months, and 24 months after surgery
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Ottawa Hospital Research Institute