Optimising Post-Centring Pavlik Time in Infant DDH: A Non-Inferiority RCT of 8 vs 12 Weeks
Trial Snapshot
- Phase
- Not Applicable
- Status
- Not yet recruiting
- Enrollment
- 110
- Locations
- 1
- Primary Endpoint
- Acetabular Index at 24 Months of Age
Study Overview
Brief Summary
Developmental dysplasia of the hip is the most common bone and joint condition in babies. It is usually treated with a harness that holds the hips in a safe position so they can develop normally. After the hip is confirmed to be in the correct position, babies are commonly kept in the harness for up to 12 weeks or more. While effective, wearing a harness for this length of time can be challenging for families. It can make everyday care such as feeding, bathing and dressing more difficult, and add stress during an important time for bonding.
This trial compares two treatment options: 8 versus 12 weeks of harness wear. The 8-week option is being tested because research has shown that most hips appear normal on ultrasound by this point. The main measure of success is whether the hip looks normal on x-ray two years after treatment. Families will also be asked about their experience and treatment-related problems.
If the shorter option is as effective as the longer option, many babies could spend less time in brace, reducing burden without compromising outcomes. Because this trial is embedded in routine care, results can be put into practice quickly and guide care for babies across Ontario and beyond.
Detailed Description
Single-centre, parallel-group, non-inferiority randomised controlled trial comparing two durations of Pavlik harness treatment (8 weeks versus the current 12-week standard) for infants ≤6 months with developmental dysplasia of the hip (DDH). Participants are randomised 1:1 after sonographic hip centring (or at brace initiation for centred dysplastic hips), with allocation stratified by key clinical factors. The primary hypothesis is that 8 weeks of post-centring wear is non-inferior to 12 weeks in terms of acetabular development at 2 years, while potentially improving caregiver experience and health-care efficiency.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Treatment
- Masking
- Single (Outcomes Assessor)
Eligibility Criteria
- Ages
- 0 Months to 6 Months (Child)
- Sex
- All
- Accepts Healthy Volunteers
- No
Inclusion Criteria
- •Age: <= 6 months of chronological age at time the maturation period is initiated (hip centred).
- •Diagnosis of DDH confirmed on standardised coronal hip ultrasound per institutional protocol, with measurement of α angle and femoral head coverage, meeting one of two entry phenotypes:
- •Decentred hip at presentation (subluxated/dislocated, femoral head coverage < 40%)
- •Centred dysplastic hip at presentation (femoral head coverage ≥ 40%, α < 60°)
- •Treatment plan: Deemed suitable for Pavlik harness as per institutional guidelines.
Exclusion Criteria
- •Previous treatment: Prior use of Pavlik harness, alternative brace, or surgical intervention for DDH. (Clarification: for infants presenting with decentred hips, enrolment is only after sonographic centring; the pre-enrolment harnessing used to achieve centring does not constitute prior treatment, and does not preclude participation)
- •Decentred hips failing to centre by 3 weeks in harness, requiring transition to fixed abduction brace or surgical reduction.
- •Secondary non-idiopathic dysplasia: Known neuromuscular disorders, connective tissue disorders, or genetic syndromes (e.g. spina bifida, arthrogryposis, Ehlers-Danlos syndrome).
- •Prematurity: Infants born at <34 weeks gestational age.
- •Medical contraindications to safe Pavlik use or study procedures.
- •Concurrent research participation: Enrolment in another interventional clinical trial that may confound outcomes.
Arms & Interventions
8-Week Arm
Participants randomised to this group will undergo an 8-week post-centring Pavlik harness maturation period. If predefined stopping criteria are not met at 8 weeks, treatment will be extended according to the study protocol. Clinical and imaging assessments will be completed according to the established care pathway.
Intervention: Pavlik Harness (Device)
12-Week Arm
Participants randomised to this group will undergo the SickKids standard 12-week post-centring Pavlik harness maturation period. If predefined stopping criteria are not met at 12 weeks, treatment will be extended according to the study protocol. Clinical and imaging assessments will be completed according to the established care pathway.
Intervention: Pavlik Harness (Device)
Outcomes
Primary Outcomes
Acetabular Index at 24 Months of Age
Time Frame: At 24 months of age, with an allowable assessment window of ±3 months.
Acetabular index, measured in degrees using the lateral-edge method on a standardised anteroposterior pelvic radiograph, will be assessed for the prespecified index hip. Two independent assessors blinded to treatment allocation will measure each radiograph, and the mean of their measurements will be used for analysis. The mean acetabular index will be compared between the 8-week and 12-week Pavlik harness treatment groups. The non-inferiority margin is 2°.
Secondary Outcomes
- Caregiver-Reported Experience Measured Using the EMBRACE Tool(At 2 weeks after randomisation and at harness discontinuation, occurring at 8 or 12 weeks after randomisation or following protocol-defined extension, up to 20 weeks after randomisation.)
- Caregiver Reported Impact of Harness Treatment on the Infant Using VAS Item(At 2 weeks after randomisation and at harness discontinuation, occurring at 8 or 12 weeks after randomisation or following protocol-defined extension, up to 20 weeks after randomisation.)
- Caregiver Reported Impact of Harness Treatment on the Caregiver Using VAS Item(At 2 weeks after randomisation and at harness discontinuation, occurring at 8 or 12 weeks after randomisation or following protocol-defined extension, up to 20 weeks after randomisation.)
- Caregiver Reported Impact of Harness Treatment on the Family Using VAS Item(At 2 weeks after randomisation and at harness discontinuation, occurring at 8 or 12 weeks after randomisation or following protocol-defined extension, up to 20 weeks after randomisation.)
- Caregiver Reported Satisfaction with DDH Care Using VAS Item(At 2 weeks after randomisation and at harness discontinuation, occurring at 8 or 12 weeks after randomisation or following protocol-defined extension, up to 20 weeks after randomisation.)
- Failure to Meet Protocol-Defined Stopping Criteria at 8 Weeks(At 8 weeks after randomisation.)
- Healthcare Resource Utilization(From randomisation through the assessment at 24 months of age (allowable assessment window of ±3 months).)
- Treatment-Related Complications(From randomisation through the assessment at 24 months of age (allowable assessment window of ±3 months).)
Investigators
Luckshman Bavan
Staff Orthopaedic Surgeon, Division of Orthopaedic Surgery, The Hospital for Sick Children
The Hospital for Sick Children