There is much debate about the nature and extent of deformities in the proximal femur in children with cerebral palsy. Most authorities accept that increased femoral anteversion is common, but its incidence, severity and clinical significance are less clear. Coxa valga is more controversial and many authorities state that it is a radiological artefact rather than a true deformity. We measured femoral anteversion clinically and the neck-shaft angle radiologically in 292 children with cerebral palsy. This represented 78% of a large, population-based cohort of children with cerebral palsy which included all motor types, topographical distributions and functional levels as determined by the gross motor function classification system. The mean femoral neck anteversion was 36.5° (11° to 67.5°) and the mean neck-shaft angle 147.5° (130° to 178°). These were both increased compared with values in normally developing children. The mean femoral neck anteversion was 30.4° (11° to 50°) at gross motor function classification system level I, 35.5° (8° to 65°) at level II and then plateaued at approximately 40.0° (25° to 67.5°) at levels III, IV and V. The mean neck-shaft angle increased in a step-wise manner from 135.9° (130° to 145°) at gross motor function classification system level I to 163.0° (151° to 178°) at level V. The migration percentage increased in a similar pattern and was closely related to femoral deformity. Based on these findings we believe that displacement of the hip in patients with cerebral palsy can be explained mainly by the abnormal shape of the proximal femur, as a result of delayed walking, limited walking or inability to walk. This has clinical implications for the management of hip displacement in children with cerebral palsy.
Most children with spastic hemiplegia have high levels of function and independence but fixed deformities and gait abnormalities are common. The classification proposed by Winters et al is widely used to interpret hemiplegic gait patterns and plan intervention. However, this classification is based on sagittal kinematics and fails to consider important abnormalities in the transverse plane. Using three-dimensional gait analysis, we studied the incidence of transverse-plane deformity and gait abnormality in 17 children with group IV hemiplegia according to Winters et al before and after multilevel orthopaedic surgery. We found that internal rotation of the hip and pelvic retraction were consistent abnormalities of gait in group-IV hemiplegia. A programme of multilevel surgery resulted in predictable improvement in gait and posture, including pelvic retraction. In group IV hemiplegia pelvic retraction appeared in part to be a compensating mechanism to control foot progression in the presence of medial femoral torsion. Correction of this torsion can improve gait symmetry and function.
We studied prospectively the impact of a hip surveillance clinic on the management of spastic hip disease in children with cerebral palsy in a tertiary referral centre. Using a combination of primary clinical and secondary radiological screening we were able to detect spastic hip disease at an early stage in most children and to offer early surgical intervention. The principal effect on surgical practice was that more preventive surgery was carried out at a younger age and at a more appropriate stage of the disease. The need for reconstructive surgery has decreased and that for salvage surgery has been eliminated. Displacement of the hip in children with cerebral palsy meets specific criteria for a screening programme. We recommend that hip surveillance should become part of the routine management of children with cerebral palsy. The hips should be examined radiologically at 18 months of age in all children with bilateral cerebral palsy and at six- to 12-monthly intervals thereafter. A co-ordinated approach by orthopaedic surgeons and physiotherapists may be the key to successful implementation of this screening programme.
