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Similarities and differences between unilateral and bilateral Perthes' disease
Andrzej Grzegorzewski1, Marek Synder, Wiesław Szymczak
1Katedra i Klinika Ortopedii i Ortopedii Dzieciecej Uniwersytetu Medycznego, Łódź
Insights
Bilateral Perthes disease typically begins 15 months earlier than unilateral cases. Both forms show similar outcomes based on the Stulberg classification, with younger age at onset correlating to better results.
Area of Science:
- Orthopedics
- Pediatric Orthopedics
- Pediatric Rheumatology
Background:
- Perthes disease affects hip joint development in children.
- Understanding differences between unilateral and bilateral presentations is crucial for treatment.
- This study compares clinical characteristics and outcomes of unilateral versus bilateral Perthes disease.
Purpose of the Study:
- To compare unilateral and bilateral Perthes disease.
- To analyze age of onset, incidence, and prognostic factors.
- To evaluate treatment outcomes using established classifications.
Main Methods:
- Retrospective analysis of 261 unilateral and 50 bilateral Perthes disease cases.
- Follow-up from onset to skeletal maturity (mean 13.4 years).
- Assessment of femoral head necrosis (Herring, Catterall) and outcome (Stulberg, Mose).
Main Results:
- Bilateral Perthes disease onset averaged 15 months earlier than unilateral.
- Peak incidence: 6-9 years (unilateral), <6 years (bilateral).
- No significant difference in Stulberg outcomes between unilateral and bilateral groups; younger onset correlated with better outcomes.
Conclusions:
- Age at onset differs significantly between unilateral and bilateral Perthes disease.
- Stulberg classification shows comparable outcomes for both forms.
- Early onset is a key factor for better prognosis in Perthes disease.
Abstract:
Background. The aim of our research was to compare unilateral and bilateral Perthes disease. Material and methods. The study population consisted of 261 patients with unilateral Perthes disease and 50 with bilateral. The hip joints were followed up from onset to the end of the growth period. The mean age at onset in unilateral disease was 7 years 1 month (range: 2.5-13 years), and in bilateral, 5 years and 10 months (range: 2.5-10.4 years). The mean follow up was 13.4 years (range: 4-50 years). Necrosis was estimated using the Herring and Catterall classifications. Outcome was evaluated using the Stulberg and Mose classification. Results. There was no correlation between gender and unilateral or bilateral Perthes disease. Onset in patients with unilateral femoral head necrosis averaged 15 months later than in the bilateral group. The greatest incidence of Perthes' disease was between age 6 and 9 in the unilateral group and under 6 in the bilateral group. There was no difference between unilateral and bilateral Perthes disease according to Stulberg classification. Age at onset correlated with Stulberg classification. Better results were achieved significantly more often in younger patients. There was no correlation between age at onset and Herring's classification in either group. Statistical analysis revealed that patients with unilateral disease in Catterall group 4 were the youngest. Conclusion. The age at onset of bilateral Perthes disease averaged 15 months earlier than with unilateral disease. There was no significant difference between unilateral and bilateral femoral head necrosis according to the Stulberg classification.
