The gait function of slipped capital femoral epiphysis in patients after growth arrest and its correlation with the clinical outcome

Abstract

Slipped capital femoral epiphysis (SCFE) represents the preliminary stage of osteoarthritis. Reliable tools for outcome evaluation should be developed to prevent persisting defects. The functional outcome of SCFE-patients after growth arrest is analysed by instrumented 3D-gait analysis (GA). The results are matched to the clinical examination findings. A total of 39 SCFE patients after growth arrest (18.8 years; BMI 26.5 kg/m²) with unilateral affection were included. The clinical results were classified according to Harris hip and clinical Heyman Herndon scores. 3D-GA-parameters were evaluated and compared to the sound side and a group of 40 healthy adults (28.0 years; 21.9 kg/m²). The subgroup analysis was performed according to clinical results. The clinical examination revealed very good results. GA could detect even small alterations. Some parameters indicated sustained functional impairments: Compared to the control group patients' walking speed (p = 0.022), step frequency (p < 0.001) and single support of the slip side (p < 0.001) decreased, while step width (p = 0.014), double support (p = 0.004) and stance time of sound side increased (p = 0.001). For kinematics patients, the sagittal range of motion (ROM) of pelvis (p < 0.001) and the external rotation of the ankle on both sides increased (p = 0.011) and sagittal ROM of hip (p = 0.002) and knee flexion of slip side (p < 0.001) decreased. The sagittal ROM of the ankle on the slip side decreased compared to the sound side (p = 0.003). Subgroup analysis revealed a positive correlation between clinically unsatisfying results and GA parameters. Functional impairments in SCFE-patients can be found even after growth arrest. Alterations are explained partly by the disease and partly by patients' constitution. BMI-matched controls and long-term follow-up are needed.