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Hip development after surgery to prevent hip dislocation in cerebral palsy: a longitudinal register study of 252
Philippe Wagner1, Gunnar Hägglund2
1Lund University, Department of Clinical Sciences, Lund, Orthopedics; Centre for Clinical Research, Uppsala University, Region Västmanland, Västerås, Sweden. phille.wagner@gmail.com.
Insights
Adductor-psoas lengthening (APL) for cerebral palsy hip displacement shows gradual MP reduction or slower progression. Varus derotation osteotomy (VDRO) offers initial MP decrease but subsequent increase, with higher reoperation risk linked to faster preoperative displacement.
Area of Science:
- Orthopedic surgery
- Pediatric orthopedics
- Cerebral palsy research
Background:
- Hip displacement is common in cerebral palsy (CP).
- Surgical options include adductor-psoas lengthening (APL) and varus derotation osteotomy (VDRO).
- Both APL and VDRO carry risks of relapse and reoperation.
Purpose of the Study:
- To compare hip displacement progression after APL versus VDRO.
- To analyze the impact of reoperations on migration percentage (MP).
- To identify factors predicting reoperation risk.
Main Methods:
- Retrospective analysis of MP data from the Swedish Surveillance Programme for CP.
- Inclusion of 158 hips treated with APL and 94 hips treated with VDRO, with ≥ 3 years follow-up.
- Use of a mixed-effects model to assess MP changes over time.
Main Results:
- APL without reoperation led to gradual MP reduction.
- APL or VDRO for reoperation showed higher preoperative displacement but slower postoperative progression.
- VDRO resulted in an initial MP decrease followed by gradual increase.
- Reoperation after VDRO was associated with higher pre- and postoperative displacement rates.
Conclusions:
- APL can lead to stable or slower hip displacement progression in CP.
- VDRO provides temporary MP reduction but is followed by progressive displacement.
- High preoperative displacement velocity and MP increase reoperation risk in CP hip surgery.
Abstract:
Background and purpose - Operative treatment of hip displacement in cerebral palsy (CP) includes adductor-psoas lengthening (APL) or varus derotation osteotomy (VDRO) of the proximal femur, sometimes combined with pelvic osteotomy. After both operations, there is a significant risk of relapse and need for reoperation. We used the migration percentage (MP) to compare the development of hip displacement after APL and VDRO. Patients and methods - All reported MP measurements for children treated with APL (n = 158) or VDRO (n = 94) and followed ≥ 3 years were obtained from the Swedish Surveillance Programme for CP. In children treated with bilateral surgery, the hip with the highest preoperative MP was analyzed. A mixed-effects model was used to estimate the development of MP with age for each child and the population mean. Results - The 104 hips that underwent APL without reoperation showed a gradually reduced MP postoperatively. The 54 hips that underwent a 2nd surgery with APL or VDRO because of redisplacement had a higher displacement rate preoperatively and continued displacement postoperatively but at a slower rate. The 94 hips that underwent VDRO showed an instantaneous decrease in MP postoperatively followed by a rate of increasing displacement. The 15 hips that underwent a 2nd VDRO had a higher rate of displacement both pre- and postoperatively. Interpretation - After APL, hip displacement either decreases or continues to increase but at a slower rate. After VDRO, the MP decreases momentarily but then gradually increases. The risk of reoperation is higher in children with a high preoperative displacement velocity and a high preoperative MP.
