Outcomes in patients with late sequelae (healed stage) of Legg-Calvé-Perthes disease undergoing arthroscopic treatment: retrospective case series.

Introduction: The residual hip deformities after Legg-Calve-Perthes disease (LCPD) cause mechanical symptoms and are associated with a pathomechanical environment that can feature femoroacetabular impingement (FAI). The aim of this study is to evaluate the clinical and radiological outcomes in residual or healed LCPD after arthroscopic treatment. Patients and methods: We retrospectively reviewed patients with LCPD amongst patients with FAI who underwent arthroscopic treatment between January 2009 and June 2013. We determined LCPD through 3-dimensional computed tomographic scans and simple radiography of the hip joint. The clinical outcomes were rated using a visual analogue scale pain score (VAS), the modified Harris Hip Score (mHHS) and hip range of motion (ROM) pre-operatively and at the 2-year follow-up. All radiographs were assessed using the Tonnis classification system pre-operatively and at the final follow-up of each patient. There were 23 patients (14 men, 9 women) with mean age 26.4 (range, 16-49) years undergoing arthroscopic treatment for FAI symptoms because of residual or healed LCPD. Results: At the 2-year follow-up, the mean VAS had improved significantly from 6.7 to 2.1, the mean mHHS had improved significantly from 62.6 to 87.4, and hip flexion and external rotation had improved significantly from 88.7 degrees to 106.5 degrees and from 20.4 degrees to 33.5 degrees, respectively (all p<0.001). The Tonnis osteoarthritis grade had not changed in any patient at the latest follow-up. Conclusions: Arthroscopic treatment for sequelae of LCPD relieved symptoms and improved range of motion, making arthroscopic treatment a good option for the sequelae of LCPD.