Introduction and aims: Leg length discrepancy (LLD) after total hip arthroplasty (THA) has been associated with a number of complications. The aim of this study was to assess the influence of LLD on the outcome of THA by comparing patients’ perception and their Oxford Hip Score with their anatomical leg length. A secondary aim was to identify the site at which LLD was created intraoperatively.

Methods: LLD and hip function were assessed in 90 patients undergoing primary total hip arthroplasty before and 3 months after surgery. Hip function was measured by the Oxford Hip Score (OHS). We measured leg length on pre- and postoperative radiographs and the position of the centre of rotation and the stem length on the postoperative radiographs.

Results: Post operatively 62% of patients’ limbs were lengthened by a mean of 9 mm. This was perceived by 43% of the lengthened patients. The OHS in patients who perceived true lengthening was 27% worse than the rest of the population. In 98%, lengthening occurred in the femoral component. 20% perceived true shortening and their OHS was not affected.

Conclusion: The problem of LLD after THA is lengthening. Accurate placement of the femoral component and especially avoiding overlengthening could significantly reduce patients’ perception of this.

We assessed leg length discrepancy and hip function in 90 patients undergoing primary total hip arthroplasty before surgery and at three and 12 months after. Function was measured using the Oxford hip score (OHS). After surgery the mean OHS improved by 26 points after three months and by 30 points after 12.

After operation 56 (62%) limbs were long by a mean of 9 mm and this was perceived by 24 (43%) patients after three months and by 18 (33%) after 12. The mean OHS in patients who perceived true lengthening was 27% worse than the rest of the population after three months and 18% worse after 12. In 55 (98%) patients, lengthening occurred in the femoral component. Appropriate placement of the femoral component could significantly reduce a patient’s perception of discrepancy of length.

Claims for personal injury after whiplash injury cost the economy of the United Kingdom more than £3 billion per year, yet only very few patients have radiologically demonstrable pathology. Those sustaining fractures of the cervical spine have been subjected to greater force and may reasonably be expected to have worse symptoms than those with whiplash injuries.

Using the neck disability index as the outcome measure, we compared pain and functional disability in four groups of patients who had suffered injury to the cervical spine. After a mean follow-up of 3.5 years, patients who had sustained fractures of the cervical spine had significantly lower levels of pain and disability than those who had received whiplash injuries and were pursuing compensation (p < 0.01), but had similar levels to those whiplash sufferers who had settled litigation or had never sought compensation.

Functional recovery after neck injury was unrelated to the physical insult. The increased morbidity in whiplash patients is likely to be psychological and is associated with litigation.

The aim of our study was to determine the current incidence and outcome of infected total knee arthroplasty (TKA) in our unit comparing them with our earlier audit in 1986, which had revealed infection rates of 4.4% after 471 primary TKAs and 15% after 23 revision TKAs at a mean follow-up of 2.8 years. In the interim we introduced stringent antibiotic prophylaxis, and the routine use of occlusive clothing within vertical laminar flow theatres and 0.05% chlorhexidine lavage during arthroplasty surgery.

We followed up 931 primary TKAs and 69 revision TKAs for a mean of 6.5 years (5 to 8). Patients were traced by postal questionnaire, telephone interview or examination of case notes of the deceased.

Nine (1%) of the patients who underwent primary TKA, and four (5.8%) of those who underwent revision TKA developed deep infection. Two of nine patients (22.2%) who developed infection after primary TKA were successfully treated without further surgery. All four of the patients who had infection after revision TKA had a poor outcome with one amputation, one chronic discharging sinus and two arthrodeses.

Patients who underwent an arthrodesis had comparable Oxford knee scores to those who underwent a two-stage revision. Although infection rates have declined with the introduction of prophylactic measures, and more patients are undergoing TKA, the outcome of infected TKA has improved very little.

Introduction: Aseptic loosening is the main cause of revision in hip replacement surgery. Improved cementation techniques have reduced the rate of loosening of the femoral component, leaving the cemented acetabular cup as the major problem, with reported loosening rates as high as 25% at 12 – 15 years. The ideal method of acetabular cementation has not been fully evaluated.

Aim: To determine the ideal thickness of cement mantle to resist torsional forces.

Method: Mahogany blocks with a 54mm hemispherical hole were used to simulate an acetabular socket. Machined aluminium cups were created in 5 sizes (52mm to 44mm) to give a cement mantle that varied in size from 1mm to 5mm. Three 10mm keyholes were drilled in the blocks and appropriate-sized spacers were inserted to ensure the mantle was accurate and even. Silicone grease was used to prevent any micro-interlock between cement and wood. The cups were then cemented into the wooden blocks using vacuum-mixed Palacos R cement and left to cure in air for 7 days at 37 °C. The constructs were tested to failure using a servo-hydraulic testing machine. Each experiment was repeated six times.

Results: The stiffness of the cement mantle varied according to thickness as follows:

Discussion: A stiffer cement mantle will transfer more torque to the bone-cement interface, possibly leading to earlier loosening of the prosthesis. This biomechanical analysis suggests that surgeons should aim to achieve a mantle at least 2mm thick. There appears to be little further mechanical advantage gained if the mantle is increased in thickness beyond 4mm.

Our aim in this study was to determine the outcome of hip arthroplasty with regard to infection at our unit. Infection after total joint arthroplasty is a devastating complication. The MRC study in 1984 recommended using vertical laminar flow and prophylactic antibiotics to reduce infection rates. These measures are now routinely used. Between 1993 and 1996, 1727 primary total hip arthroplasties and 305 revision hip arthroplasties were performed and 1567 of the primary and 284 of the revision arthroplasties were reviewed between five and eight years after surgery by means of a postal questionnaire, telephone interview or examination of the medical records of those who had died.

Seventeen (1.08%) of the patients who underwent primary and six (2.1%) of those who underwent revision arthroplasty had a post-operative infection. Only 0.45% of patients who underwent primary arthroplasty required revision for infection.

To our knowledge this is the largest multi-surgeon audit of infection after total hip replacement in the UK. The follow-up of between five and eight years is longer than that of most comparable studies. Our study has shown that a large cohort of surgeons of varying seniority can achieve infection rates of 1% and revision rates for infection of less than 0.5%.

The rate of deep infection following primary joint replacement has reduced to below 1%, but the cost remains high. The surgical team is the most important source of bacteria causing infection. All surgical gowns are susceptible to penetration by these organisms, which may then spread to the wound via the surgeon’s hands or contact with wet drapes without ever being airborne.

There is insufficient clinical data on the penetration of bacteria through surgical gowns, in part due to the difficulty of in vivo measurement. A simple new method was developed, using petri dishes filled with horse blood agar that were attached to the outside of the gown material. This was used to assess bacterial penetration through disposable spun-bonded polyester gowns and re-usable woven polyester gowns during normal use.

There was a significant difference between the two gown types when tested in the axilla (p < 0. 05), the groin (p < 0. 05) and the peri-anal region (p < 0. 01), with the disposable gowns performing to a higher standard.

Re-usable gowns demonstrated significant variation in penetrability. This is most likely to be due to the number of laundering and sterilisation cycles that they had undergone. Unless the continued satisfactory performance of multiple-use gowns can be guaranteed, they may be unsuitable for use in orthopaedic implant surgery.

Aseptic loosening of the acetabular component is the main reason for revision hip arthroplasty surgery with loosening rates reported at 25% at 12–15years. The optimum method of acetabular preparation and cementation technique has not been fully evaluated. Clinical follow-up studies suggest multiple keyholes improve survival rates.

Keyholes increase penetration of cement and torsional resistance of the bone-cement interface. Some studies support the traditional three 1/2 inch keyholes other studies have shown multiple smaller holes improve stability. The optimum size and number of holes to provide the strongest fixation has yet to be determined.

Using an established 54mm diameter acetabular model, mahogany, three sizes of keyhole were tested-3x10mm holes, 12x5mm, and 48x2.5mm- the surface area of the defects created were the same in each group. The model acetabulum was filled with cement and a metal central bar inserted through which torque could be applied using an Instron machine. Six specimens from each group were tested. Three 10mm holes produced a significantly stronger resistance to torque when compared to 2.5mm (p≤0.017) and 5mm holes (p≤0.001). There was no significant difference between 2.5mm and 5mm holes (p≤0.139). Each addition of a further 10mm hole significantly increased the torque strength until the model was destroyed at six holes.

In laboratory testing larger key holes provide a stronger cement-acetabular interface.

Twelve patients undergoing total hip replacements were given 600mg linezolid as a 20min intravenous infusion along with conventional prophylaxis of 1gm cefamandole immediately before surgery. Routine total hip arthroplasty was performed and at timed intervals during surgery, samples of bone, fat, muscle and blood were collected for assay by HPLC analysis. Samples of haematoma fluid that formed around the operation site and further blood samples were also collected at timed intervals following the operation for assay. The penetration of linezolid into bone was rapid with mean levels of 9.1mg/L (95% CI: 7.7–10.6mg/L) achieved at 10min after the infusion, decreasing to 6.3mg/L (95% CI: 3.9–8.6mg/L) at 30min. Correcting for the simultaneous blood concentrations gave values for bone penetration of 51% at 10min, 60% at 20min and 47% at 30min. although the penetration of linezolid into fat was also rapid, mean levels and degree of penetration were approximately 60% of those seen in bone at 10min: 4.5mg/L (95%CI:3–6.1mg/L; penetration 27%) 20min: 5.2mg/L (95% CI:4–6.4mg/L; penetration 37%) and 30min:4.1mg/L (95% CI:3.3–4.8mg/L; penetration 31%). For muscle, the corresponding values were 10min: 10.4mg/L (95%CI:8.1–12.7mg/L; penetration 58%), 20min 13.4mg/L (95%:10.2–16.5mg/L; penetration 94%) and 30min 12mg/L (95% CI:9.2–14.8mg/L; penetration 93%). Mean concentration of linezolid in the haematoma around the operation site were 8.2mg/L at 6–8h and 5.6mg/L at 8–10h after the infusion and 7mg/L at 2–4h following a second 600mg infusion given 12h postoperatively.

We conclude that linezolid exhibits rapid penetration in bone, fat and muscle of patients undergoing hip arthroplasty to achieve levels in excess of the MIC for sensitive organisms (MIC of < _ 4mg/L); with therapeutic levels maintained in the drainage which surrounds the operation site for more than 16h. This pharmaco-kinetic profile is similar to those of agents currently used for the treatment of bone and associated soft tissue infections and suggests a role for linezolid in the management of such patients

We undertook a prospective, randomised study to compare the analgesic effect of injection of steroid and of extracorporeal shock-wave therapy (ESWT) for the treatment of tennis elbow. Group 1 received a single injection of 20 mg of triamcinolone with lignocaine while group 2 received 2000 shock waves in three sessions at weekly intervals. After six weeks there was a significant difference between the groups with the mean pain score for the injection group falling from 66 to 21 compared with a decrease from 61 to 35 in the shock-wave group (p = 0.05). After three months, 84% of patients in group 1 were considered to have had successful treatment compared with 60% in group 2.

In the medium term local injection of steroid is more successful and 100 times less expensive than ESWT in the treatment of tennis elbow.

Percutaneous repair of the ruptured tendo Achillis has a low rate of failure and negligible complications with the wound, but the sural nerve may be damaged. We describe a new technique which minimises the risk of injury to this nerve.

The repair is carried out using three midline stab incisions over the posterior aspect of the tendon. A No. 1 nylon suture on a 90 mm cutting needle approximates the tendon with two box stitches. The procedure can be carried out under local anaesthesia.

We reviewed 27 patients who had a percutaneous repair at a median interval of 35 months after the injury. They returned to work at four weeks and to sport at 16. One developed a minor wound infection and another complex regional pain syndrome type II. There were no injuries to the sural nerve or late reruptures. This technique is simple to undertake and has a low rate of complications.

Nerve injury is a rare complication of total hip replacement which may be related to the exposure used for the operation. The posterior approach is traditionally associated with injury to the sciatic nerve. We have compared the incidence of nerve injury after primary total hip replacement (THR) using either a posterior or a direct lateral approach.

We studied 42 consecutive patients undergoing primary total hip replacement. The surgeons used a posterior (22 patients) or direct lateral (20 patients) approach in accordance with their normal practice. The obturator, femoral, posterior tibial and common peroneal nerves were assessed clinically and electrophysiologically by electromyography (EMG) and measurement of the velocity of nerve conduction before operation and at four weeks after.

All patients were free from symptoms of nerve injury after operation but five lesions were identified in four patients by the electrophysiological studies; the obturator nerve was involved in two, the femoral in one, the common peroneal in one and the posterior tibial in one. All these injuries occurred using the lateral approach.

Clinical assessment alone underestimates the incidence of nerve injury complicating THR. Our study does not confirm the association of nerve injury with the posterior approach which had been described previously.

Forty patients with a whiplash injury who had been reviewed previously 2 and 10 years after injury were assessed again after a mean of 15.5 years by physical examination, pain and psychometric testing.

Twenty-eight (70%) continued to complain of symptoms referable to the original accident. Neck pain was the commonest, but low-back pain was present in half. Women and older patients had a worse outcome. Radiating pain was more common in those with severe symptoms.

Evidence of psychological disturbance was seen in 52% of patients with symptoms. Between 10 and 15 years after the accident 18% of the patients had improved whereas 28% had deteriorated.