Despite extensive experience with prosthetic replacement for the reconstruction of limbs following juxta-articular resection of tumours, there are few reports of prosthetic replacement of the distal radius. We present two cases of massive bone defects of the distal radius in which alumina ceramic prosthetic replacements were used. We evaluated the patients more than ten years after the procedure. Both patients had degenerative changes to the wrist. This, however, was not associated with pain or decreased function, and both had returned to their previous occupation after surgery. When a patient has a massive defect of the distal radius, reconstruction using a ceramic prosthesis is a reasonable alternative to using autograft. This method of treatment results in little pain, a moderate range of movement and satisfactory function.
We examined osteochondral autografts, obtained at a mean of 19.5 months (3 to 48) following extracorporeal irradiation and re-implantation to replace bone defects after removal of tumours. The specimens were obtained from six patients (mean age 13.3 years (10 to 18)) and consisted of articular cartilage (five), subchondral bone (five), external callus (one) and tendon (one). The tumour cells in the grafts were eradicated by a single radiation dose of 60 Gy. In three cartilage specimens, viable chondrocytes were detected. The survival of chondrocytes was confirmed with S-100 protein staining. Three specimens from the subchondral region and a tendon displayed features of regeneration. Callus was seen at the junction between host and irradiated bone.
Multiple tumours of peripheral nerves are often seen in patients with neurofibromatosis of type 1 or 2. Multiple schwannomas may occur without other manifestations of neurofibromatosis. We have reviewed 12 patients with multiple schwannomas arising from peripheral lesions who did not fulfil the criteria for either type of neurofibromatosis. Four had spinal and one an intracranial lesion in addition to the peripheral tumours. Two patients had one and three The large size of tumours, the difficulties of histological diagnosis on biopsy, and the confusion with neurofibromatosis can lead to overtreatment. Malignant change seldom, if ever, occurs in patients with multiple schwannomas.
We have reviewed 37 patients under the age of 18 years with lesions of the lumbar posterior end plate. All but one were active in sport, and most were seen because of low back pain. An abnormality was commonly found at the inferior rim of the body of L4 and at the superior rim of the sacrum. All adjacent intervertebral discs showed a decrease of signal intensity on the T2-weighted MRI. In 12 patients there was no interposed tissue at the posterior end-plate lesions. When disc material had migrated posteriorly none protruded beyond the posterior margin of the end plate, the dissociated portion of which was the main element compressing neural tissue. The posterior end-plate lesion should be regarded as a vertebral non-articular osteochondrosis.
We investigated 185 adolescents under the age of 19 years with spondylolysis. All but five were active in sport. The pars defect was classified into early, progressive and terminal stages. Of the 346 pars defects in 185 patients, 39.6% were early, 29.5% progressive and 30.9% in the terminal stages. Conservative management produced healing in 73.0% of the early, 38.5% of the progressive and none of the terminal defects. These results suggest that spondylolysis is caused by repetitive microtrauma during growth and can be successfully treated conservatively if treatment is started in the early stage. There was elongation of the pars interarticularis as the pars defect progressed, and this is likely to be a consequence of the defect rather than a contributing cause.
