Background

Advances in diagnosis and treatment should mean that hindquarter amputation is now rarely needed. Unfortunately this is not the case. We have performed 166 of these amputations in the past 36 years. We have investigated the reasons why this procedure is still required and the outcomes following it.

Introduction

Neurological involvement occurs in 10-30% cases of caries spine. Surgical debridement and stabilisation is needed to decompress the cord and prevent progression of deformity. This prospective study was undertaken to determine the efficacy of operative treatment in the management and neurological recovery in patients with caries spine with neural deficit.

Children with diplegic cerebral palsy develop progressive musculoskeletal deformities with deterioration in their gait. Multilevel surgery is a well-established treatment modality involving a combination of soft tissue lengthening and correction of bony deformities.

At Bristol Royal Children's Hospital we have identified a cohort of 45 children with diplegic cerebral palsy who have undergone multilevel surgery. Video gait analysis had been performed pre-operatively and three years post-operatively. We utilised the Edinburgh Visual Gait Score (EVGS)^[1], a validated system that allows direct comparison with gait videos taken during different periods of the patient's treatment. Seventeen measurements are taken per limb at each stage. The patients were also categorised according to the Functional Walking Score (FWS) ^[2] that assesses their level of independence.

Post-operative results demonstrate a significant improvement in gait score on both the EVGS and FWS. Patients whose gait was more severely affected prior to surgery had the greatest improvement in mobility and functional scores. Patients consistently had significant improvements in hip and knee extension in stance phase, with more modest improvement in knee flexion in swing with persistent co-contraction. Both initial contact and heel lift were consistently abnormal pre-operatively, but few patients achieved a heel strike and normal heel lift post-operatively. We are proceeding with a long-term follow-up of this cohort of patients at 15 years following surgery.

The combination of using detailed video gait analysis with functional assessment is a valuable tool in retrospective assessment of patients' outcome following surgery. It gives a quantitative evaluation of progression over time as well as allowing comparison with a cohort of patients to estimate the future level of functional independence.

Since 1970, 2200 primary endoprosthetic replacements have been carried out at our Unit for bone tumours. 3% were carried out in the 1970s, 21% in the 1980s, 33% in the 1990s and 43% since 2000.

The most common diagnosis was osteosarcoma (839)(38%) followed by metastatic disease (18%) and chondrosarcoma (13%). The most common site was the distal femur (35%) followed by the proximal femur and proximal tibia. The least common sites were the scapula and distal radius. The mean age at operation was 35 but varied widely, being 19 in patients with osteosarcoma and 58 for those with metastases. 239 extendable prostheses were inserted in children. 50% of the patients were alive at 10yrs and 42% at 20yrs. 7% required an amputation either for local recurrence or infection.

The failure rate of the prostheses varied by age and site, with pelvic and proximal tibial replacements having the highest risk of infection and proximal humeral replacements the lowest risk of any complication. The failure rates of the most common prostheses (distal femur and proximal tibia) have improved over time and are now ~ 1.5% per year. Hydroxyapatite collars have largely resolved the problem of aseptic loosening. Silver coated prostheses have been used in 48 complex cases with encouraging results in controlling infection. Functional scores averaged 80% and were the same for revision as for primary implants.