The association between vitamin-D-resistant rickets and linear sebaceous naevus syndrome is extremely rare. Only eight cases have been described in the English literature and in none were the skeletal aspects addressed. We present three new cases and describe the musculoskeletal features. The details and outcome of surgery for correction of the deformities are discussed. The disturbances of metabolism of vitamin D and the effects of pharmacological treatment are also described.

We review the results of a modified quadricepsplasty in five children who developed stiffness of the knee after femoral lengthening for congenital short femur using an Ilizarov external fixator which spanned the knee.

All had a full range of movement of the knee before lengthening was undertaken. Unifocal lengthening was carried out in the distal metaphysiodiaphyseal region of the distal femur with a mean gain of 6.5 cm. The mean percentage lengthening was 24%.

At the end of one year after removal of the Ilizarov frame and despite intensive physiotherapy all patients had stiffness. Physiotherapy was continued after the quadricepsplasty and, at the latest follow-up (mean 27 months), the mean active flexion was 102° (80 to 130). The gain in movement ranged from 50° to 100°. One patient had a superficial wound infection which settled after a course of oral antibiotics. None developed an increased extension lag after surgery and all were very satisfied with the results. Quadricepsplasty is a useful procedure for stiffness of the knee after femoral lengthening which has not responded to physiotherapy.

Discitis is uncommon in children and presents in different ways at different ages. It is most difficult to diagnose in the uncommunicative toddler of one to three years of age. We present 11 consecutive cases. The non-specific clinical features included refusal to walk (63%), back pain (27%), inability to flex the lower back (50%) and a loss of lumbar lordosis (40%). Laboratory tests were unhelpful and cultures of blood and disc tissue were negative.

MRI reduces the diagnostic delay and may help to avoid the requirement for a biopsy. In 75% of cases it demonstrated a paravertebral inflammatory mass, which helped to determine the duration of the oral therapy given after initial intravenous antibiotics.

At a mean follow-up of 21 months (10 to 40), all the spines were mobile and the patients free from pain. Radiological fusion occurred in 20% and was predictable after two years. At follow-up, MRI showed variable appearances: changes in the vertebral body usually resolved at 24 months and recovery of the disc was seen after 34 months.

Between January 1987 and December 1988 there were 7575 births in the Swansea maternity unit. Of these 823 (10.9%) were considered to be at ‘high risk’ for developmental dysplasia of the hip (DDH). Static ultrasound examination was performed in each case and the results classified on the basis of the method of Graf. A total of 117 type III–IV hips in 83 infants was splinted using the Aberdeen splint.

Radiographs of these hips were taken at six and 12 months. Hilgenreiner’s measurements of the acetabular angle were made in all cases and the development of the femoral capital epiphysis was assessed by measuring the epiphyseal area. The effect of splintage on the acetabular angle and the epiphyseal area between the normal and abnormal splinted hips was compared. Radiographs of 16 normal infants (32 normal unsplinted hips) were used as a control group.

This cohort has now been followed up for a minimum of nine years. There have been no complications as a result of splintage. The failure rate was 1.7% or 0.25 per 1000 live births. No statistical difference was found when comparing the effect of splintage on the acetabular angle and epiphyseal area between normal and abnormal splinted hips and normal unsplinted hips.

Our study has shown that while the Aberdeen splint had a definite but small failure rate, it was safe in that it did not produce avascular necrosis. The current conventional view that a low rate of splintage is always best is therefore brought into question if the Aberdeen splint is chosen for the management of neonatal DDH.

Children with a mucopolysaccharidosis or mucolipidosis suffer progressive disability of the hands, particularly in relation to dysfunction of the median nerve. This is an increasing problem because bone-marrow transplantation has dramatically improved survival without apparently changing the musculoskeletal manifestations. We have reviewed 48 children with these syndromes who required carpal tunnel decompression, recording symptoms, signs, radiological, electrophysiological and operative findings, histology and upper-limb function. In these children the carpal tunnel syndrome differs from that seen in adults. Symptoms are rare but signs such as decreased sweating, pulp atrophy, thenar wasting and manual clumsiness are much more common. At operation, the flexor retinaculum was thickened and a mass of white tenosynovium engulfed the flexor tendons. Most patients had some definite nerve constriction with a thickened epineurium.

Functional improvement was seen after early decompression, with some benefit from simultaneous tendon release. Regular physiotherapy helped to maintain increased hand movement.

We describe our assessment protocol, the physiotherapy and operative regime and the standard functional review which helps to maximise function in the hands and upper limbs of these children.

We have studied retrospectively 37 hips in 36 children at an average of 91 months after simultaneous open reduction and Salter innominate osteotomy for developmental hip dysplasia. At the latest review 97.3% were clinically and 83.8% radiologically good or excellent. In three hips (8%) there were signs of avascular necrosis, but only one had been symptomatic. There were no cases of recurrent posterior displacement.