Does the level of proximal femur rotation osteotomy influence the correction results in patients with cerebral palsy?

Proximal femur external rotation osteotomy is a common procedure used for the correction of increased femur anteversion and hip internal rotation in cerebral palsy (CP). Different levels of osteotomy have been used at the proximal femur, but there are no studies in the literature comparing the results in CP. Patients with spastic CP, Gross Motor Function Classification System (GMFCS) I-III, who had undergone a femoral rotational osteotomy from August 1998 to August 2007, and with complete documentation at gait laboratory were included in the study. Patients were divided into two groups according to the level of osteotomy at the proximal femur. Group A [Dynamic Compression Plate (DCP) group] included 24 patients (36 osteotomies), and the osteotomy in this group was performed below the lesser trochanter. In Group B (Blade Plate group), 29 patients (35 osteotomies) were included and the level of osteotomy was above the lesser trochanter. Age at surgery, sex distribution, follow-up time, previous surgical procedures, surgical procedures performed in the same session as femur osteotomy, GMFCS level, topographic classification, clinical findings (internal and external hip rotation, and femur anteversion), and hip rotation at kinematics were analyzed and the results were compared between groups. Groups A and B were matched in terms of the sex distribution, follow-up time, GMFCS levels, and severity of clinical findings and hip internal rotation at kinematics before surgery. The mean age of the patients at surgery was 9.24 years in group A and 12 years in group B, and this difference was significant on performing statistical analysis (P=0.004). The number of patients who had undergone previous hip adductors' tenotomy was higher in group B (P=0.036). Improvements in clinical and kinematics parameters were observed in both groups after femur osteotomy (P<0.001). The increase in hip external rotation at clinical examination and the reduction in hip internal rotation at kinematics did not show differences between groups A and B on performing statistical analysis. However, reduction of femoral anteversion (P=0.032) and hip internal rotation (P=0.002) were more remarkable in group B. In conclusion, reduction of hip internal rotation and femur anteversion at physical examination were more significant in patients with intertrochanteric osteotomies; however, improvement in kinematics was observed in both groups after surgical procedures.