Hinged versus fixed arthrodiastasis in late-onset Perthes’ disease

Abstract

Background Late-onset Perthes’ disease occurs in patients older than 8 years and constitutes approximately 20% of cases and is known for its aggressive course and poor outcome with chronic hip pain and stiffness. The best treatment is still unknown, and various surgical treatment options have been proposed, but they have some inherent drawbacks. Arthrodiastasis had been introduced as a treatment method for late-onset Perthes’ disease. Patients and methods This is a prospective study performed in Suez Canal University hospitals during the period from October 2010 to December 2014. Twenty hips were divided into two groups. Group I consisted of 10 hips treated by hinged arthrodiastasis. Group II consisted of 10 hips treated by fixed arthrodiastasis. Arthrodiastasis was done by external ring fixator. At the end of the follow-up period, patients were evaluated clinically and radiologically. Results At the end of the follow-up period, which ranged from 24 to 30 months, with a mean of 27.6 months for group I, and a mean of 26.2 months for group II, preoperative and postoperative clinical features and outcome scoring systems in both groups showed improvement and statistically significant relationship in values of limb length discrepancy, total hip range of motion, modified Harris hip score, and epiphyseal index. Comparing postoperative clinical features and outcome scoring systems between both groups at final follow-up showed values in group I better than group II, but there is no statistically significant relationship. Conclusion Arthrodiastasis either hinged or fixed using ring external fixator combined with adductor tenotomy is an excellent and reliable method for treatment of late-onset Perthes’ disease, where prognosis is usually poor and conventional methods of treatment are not reliable.