Purpose: Hand injuries rank as the second most common category in A& E medicolegal claims. Accurate diagnosis and treatment is essential, with a high index of suspicion and low threshold for exploration. The first clinical examination for tendon and nerve injuries is crucial for prioritisation in a busy unit and surgical/anaesthetic planning.

Method: St Andrew’s being a tertiary level hand unit in the United Kindgom, has a significant throughput of trauma (head to feet) with 10–15 cases daily. Most patients are reviewed in the daily consultant/senior trainee–lead trauma clinic, with entries recorded on a computerised trauma database. We analysed the pattern of tendon and nerve injuries and accuracy of pre-operative assessment compared to operative findings. The database for a 12-month period was reviewed. After exclusions, 1670 sequential cases of adults with below-elbow, soft tissue injuries and complete clinical/operative notes were included. There were 1573 structures potentially injured in 823 digits, including 994 named tendons and 568 nerves. Knife and glass injuries predominated and 89% were operated on within 24 hours of assessment.

Results: Anatomical accuracy was greater than 98% for both tendons and nerves. Border nerves (index radial and little finger ulnar) were particularly at risk. Assessment of severity (nil, partial or total) was accurate in 60 % overall – 58% for nerves and 62% for tendons. Highest error rates(excluding true negatives) were same in all the digits. Zonewise, high error rates were encountered in flexors and nerves at wrist, while for the extensors it was at E6. On analysis of tendons individually, high false positives were encountered with FDS and FDP among the flexors.

Conclusion: This findings support our practice of low threshold for exploration. Distribution and accuracy by structure and zone are discussed, with recommendations for diagnostically difficult regions. Knowledge of potential pitfalls may prevent inappropriate choices of anaesthetic and aids prioritisation.

Introduction: Patients’ demands from hip arthroplasty are changing. Bigger bearings with alternative bearing surfaces are marketed to meet these demands. The aim of this study is to investigate the level of function achieved by patients with the larger hard-on-hard hip replacements in the short term.

Methods: Three groups of patients were identified from the arthroplasty register. The two study groups were those who received a 36mm ceramic-on-ceramic hip replacement (28 patients) and those who received larger metal-on-metal hip replacements (56 patients). The control group (25 patients) was age matched patients receiving 28mm hip replacements with a polyethylene acetabular component.

All patients received postal questionnaires comprising the Oxford Hip Score, the HOOS score and a satisfaction score. Routine yearly radiological examination was also undertaken. Demographic data are shown in Table 1.

Results: All three groups showed significant improvement in the oxford hip score after hip arthroplasty. Those with the larger head sizes had significantly lower scores than those with 28mm.

Activity scores in the HOOS hip survey were not significantly different in the three groups.

There was no difference in satisfaction scores and whether patients would have the same operation again.

Discussion: Our findings suggest that in the short term, functional levels achieved following hip replacement are not influenced by the size of bearing. Should these results be reproduced in larger and longer term studies use of these costly implants may have to be questioned.

Introduction: We present our results of the first 413 Charnley arthroplasties performed by and under the supervision of the senior surgeon, using the posterior approach.

Methods: This is a prospective study of clinical and radiographic outcomes. Four hundred and thirteen hip replacements were performed in 380 patients (215 female and 165 male) between 1992 and 1996. The mean age at the time of primary surgery was 67 years (28 – 91 years).

Results: The primary aetiology in 297 of the hips was osteoarthritis. Eighty-two had rheumatoid arthritis.

Eleven patients (3%) had one or more episodes of dislocation.

There were 22 revisions. Three of the revisions were carried out for infection, and a further 2 for recurrent dislocation. Aseptic loosening was the cause of failure in the remaining 17.

Thirty three patients (36 hips, 9%) could not be traced at the time of the final follow-up. There was significant and maintained improvement in pain and function scores.

One hundred and thirty eight patients (146 hips) had died at the time of the final follow-up.

The best and worst case survivorship figures at 10 years were 93 +/− 2% and 83 +/− 2%, and those at 14 years were 88 +/− 4% and 78 +/− 4%, respectively, with revision for any reason as the end-point.

Discussion: Excellent results for the Charnley hip are possible using the posterior approach and surgeons of varying experience. The results presented compare favourably with the published data and confirm that the Charnley remains the gold-standard for longevity in hip arthroplasty. The newer and more costly implants not only need to reproduce these results but also match the cost effectiveness of this prosthesis.

Objective: A patient-specific finite element model of the spine is being developed to aid the surgeon in the diagnosis and clinical management of spinal conditions¹. To validate the application of the computer model, a laboratory validation spine is being developed. This study is concerned with the development and basic characteristics of the intervertebral disc component of the laboratory spine.

Method: The external profile of the laboratory disc was determined from CT images of a cadaveric spine. A two-part silicon rubber was used to form the annulus part of the disc. Prior to sealing it was possible to fill the cavity with an appropriate medium (such as grease or oil) to represent the nucleus pulposus with the further option of applying external pressurisation through a small pressure inlet in the wall of the disc. The laboratory disc was then tested in denucleated form, and grease-filled with initial intradiscal pressures of 0, 0.1, 0.2 and 0.3 MPa. A finite element model of the disc was also developed and used to investigate the characteristics of the laboratory disc.

Results: The agreement between the finite element results and experimental test results was excellent and the compressive and flexural load-deflection characteristics of both intact and denucleated laboratory discs were found to lie within the range of values reported in the literature for cadaveric discs. Disc bulge characteristics of the intact and denucleated silicon discs were also similar to that observed with natural discs in vitro.

Conclusions: An artificial disc for a laboratory validation spine has been developed and shown to have representative characteristic properties in compression loading. The disc is now being modelled and tested in torsion.