This is a prospective study of 107 repairs of obstetric brachial plexus palsy carried out between January 1990 and December 1999. The results in 100 children are presented. In partial lesions operation was advised when paralysis of abduction of the shoulder and of flexion of the elbow persisted after the age of three months and neurophysiological investigations predicted a poor prognosis. Operation was carried out earlier at about two months in complete lesions showing no sign of clinical recovery and with unfavourable neurophysiological investigations.

Twelve children presented at the age of 12 months or more; in three more repair was undertaken after earlier unsuccessful neurolysis. The median age at operation was four months, the mean seven months and a total of 237 spinal nerves were repaired.

The mean duration of follow-up after operation was 85 months (30 to 152). Good results were obtained in 33% of repairs of C5, in 55% of C6, in 24% of C7 and in 57% of operations on C8 and T1. No statistical difference was seen between a repair of C5 by graft or nerve transfer.

Posterior dislocation of the shoulder was observed in 30 cases. All were successfully relocated after the age of one year. In these children the results of repairs of C5 were reduced by a mean of 0.8 on the Gilbert score and 1.6 on the Mallett score. Pre-operative electrodiagnosis is a reliable indicator of the depth of the lesion and of the outcome after repair. Intra-operative somatosensory evoked potentials were helpful in the detection of occult intradural (pre-ganglionic) injury.

Aim To determine if tissue metabolism varies in supraspinatus tendons with distance from the edge of the rotator cuff tendon tear and also with differing size of tear.

Background Tissue metabolism can be assessed by measuring oxygen and nitrous oxide concentrations within the tissue. Viable tendon tissue consumes oxygen and contains nitrous oxide (used in the general anaesthetic) from the blood stream. Non-viable tendon tissue will not consume oxygen but will contain nitrous oxide.

Methods Oxygen and Nitrous Oxide concentrations were measured amperometrically using silver needle microelectrodes.

The needle was inserted into the supraspinatus tendon of patients with massive, large, medium and small full thickness rotator cuff tears and patients with partial thickness and no tears. Patients undergoing open stabilisation were used as controls. Measurements were made at a number of quantifiable points from the tendon edge to allow the creation of a topographical map of tissue metabolism. Oxygen consumption was calculated using measured oxygen and nitrous oxide levels at each point.

Results In patients with rotator cuff tears oxygen consumption was significantly lower near to the edge of the tear.

Patients with impingement syndrome but no evidence of a rotator cuff tear also showed a decreased level of oxygen consumption in the anterior part of supraspinatus, but this was significantly higher than the levels seen in the torn tendon.

The control group showed no significant alteration in oxygen levels

Conclusion Patients with rotator cuff tendon tear demonstrate significantly reduced levels of tissue metabolism. This reduction in tissue viability is significantly greater at the edge of the tear and in larger tears. Patients with intact tendons and impingement syndrome also demonstrate minor reduction in tissue tendon viability compared with controls.

Background and Purpose: Intervertebral discs are the largest avascular tissue sources in the human body. The transport of vital nutrients and oxygen into and metabolic waste products out of the disc, relies mainly on the diffusion through the disc matrix. The health or degree of degeneration of the disc is thought to be directly related to the transport properties of the disc. The diffusivity of nutrients and metabolites varies with matrix composition and especially with matrix hydration. The hydration of the disc varies by approximately 25% in the normal 24hour loading cycle of human beings. This work addresses the question of the effect of hydration of the disc tissue on the solute diffusivity.

Methods: Measurements of the diffusion of solutes were performed in ca. 2year bovine caudal discs. Diffusivity of dissolved oxygen and nitrous oxide was monitored electrochemically. Diffusivity of 0.05 to 70kDa solute species was determined by measuring concentration gradients using either fluorescent or radiotracers. Hydration was controlled by either mechanical static load or by osmotic equilibration.

Results: Diffusion rates varied with solute molecular weight (MW), decreasing steeply with an increase in MW. For small solutes, the diffusivity was greater in the nucleus than the outer annulus, but this difference was insignificant for the larger solutes. Diffusivity changed by a significant amount with hydration changes, which were significantly affected by loading. Application of a 0.2MPa mechanical load led to a drop in hydration of the outer annulus and nucleus of 33.3% and 42.1% and corresponding falls in diffusivity of glucose of 34.0% and 81.3% respectively.

Conclusions: The large changes in hydration experienced during normal loading of the spine have a marked effect on nutrient and metabolite diffusivity. This effect has not been considered previously but could significantly influence supply of nutrients to the disc cells.

Primary disc space infections are thought to occur in children because of the abundant vascularity of the disc prior to skeletal maturity, and while they generally resolve with treatment, little is known about the long-term consequences on the spine.

An ovine model of discitis was used to investigate the effects of discitis on spinal development in the growing sheep. Six-week-old lambs underwent lumbar discography at multiple spinal levels using either radiographic contrast inoculated with Staphylococcus epidermidis (inoculated group) or radiographic contrast only (control group). Plain x-rays of the spines were taken at intervals up to 18 months before the animals were killed and the spines removed for histologic and morphometric analysis.

Discs from animals in the control group were radiologically and histologically normal at all time points, and as expected there was a steady increase in vertebral body and disc dimensions. Although not all inoculated animals showed histologic evidence of discitis, disc abnormalities were evident from an early stage. In particular disc height was significantly reduced from 2 weeks after inoculation and vertebral body dimensions were significantly reduced from one year.

Infection of discs at a young age, whether or not it progresses to discitis, has a significant effect on spinal development.

A single reviewer reviewed 184 consecutive wrist arthroscopies performed by one surgeon. Epidemiological data and clinical findings including outcome measures were recorded. It was noted that clinical assessment was more accurate than modern Imaging modalities in diagnosing wrist injuries apart from TFCC injuries. The results also showed a low intervention rate with 37 further procedures performed. There was a low complication rate.

Wrist arthroscopy is a safe and accurate diagnostic procedure.

Septic arthritis has been regarded as rare in haemophiliacs, but its incidence may have increased since HIV infection has become widespread in these patients. We describe six cases treated at one haemophilia unit over a two-year period and discuss their investigation, diagnosis and treatment. Four of the patients were seropositive to anti-HIV.