Introduction: As knee arthroplasty is becoming more commonplace in the working population its outcome and probability of return to work is of interest. Despite a wealth of anecdotal evidence about patient return to work post knee arthroplasty there is nothing published in the recent literature. The NHS Direct patient information website quotes patients return to work about 6 to 8 weeks post knee arthroplasty. In order to address this lack of informed information we conducted a retrospective survey.

Methods: 148 consecutive patients of working age, who underwent knee arthroplasty in 2007 were identified by our Electronic Patients Record. (52 male, 96 female, average age 58 years (range 37–65 years)) They were asked to complete a simple questionnaire relating to their occupational history, arthroplasty satisfaction and their current working capacity.

Results: Our survey had a response rate of 67% (99/148 responders, 64 female and 35 male), with a range of follow up from 7 to 19 months. 39% of patients were in employment at the time of their arthroplasty, with 46 % (46/99) returning to some working capacity post surgery. 32% (32/99) patients were able to return to their exact same employment. 88% (28/32) of these patients had worked up to the date of their arthroplasty. There was no correlation between operative indication or type of prosthesis implanted and patients who returned to employment and those who did not.

Conclusion: Despite high expectation in lay literature of ability to work post knee arthroplasty, only 46% of our patients returned to any form of employment. For patients who returned to work, the duration of sick leave prior to their surgery was a strong predictor of whether they returned to any form of employment. Caution must be exercised when informing patients of likelihood of return to work post knee arthroplasty.

Most hospitals have introduced digital radiography (PACS) systems. Accurate pre-operative templating prior to hip arthroplasty requires precise information on the magnification of the digital image. Without this information the benefits of expensive digital templating programs (Orthoview-£10000) cannot be realised.

To determine the magnification of a digital image involves the placement of a “calibration object” at the level of the hip joint. This is unpopular with patients and radiographers alike. We describe a method that requires a single measurement to be made from the greater trochanter to the digital film.

An AP pelvis x-ray was taken of 50 patients with hip replacements. The “predicted” magnification was calculated using the new method. As the size of the head of the prosthesis was known the “actual” magnification could be calculated also. There was no significant difference at 0.05, Wilcoxon T, 2-tail test.

Conventional radiography, which assumes a magnification of 20%, results in errors up to 11%. Templating may therefore predict an incorrectly sized prosthesis. Our method is as accurate as methods using a calibration object whilst being acceptable to patients and staff. Its use should lead to more accurate pre-operative templating prior to total hip arthroplasty

To review the outcome of patients with deep infection using a new 2-stage revision technique.

A management plan consisting of initial debridement, insertion of antibiotic spacers and 2 weeks of intravenous antibiotics is currently used. No further antibiotics are given systemically. If blood tests are satisfactory at 12 weeks, reimplantation occurs. Patients are encouraged to partially weight-bear and perform a range of motion exercises with their spacers in place. The necessary data has been prospectively collected to identify predictors of success.

Thirty four patients have been identified and fully followed up for more than 1 year. 27 patients have over 2 years of follow-up. When looking at all of the patients we have achieved an 82% success rate. For patients whose only previous major surgery was their arthroplasty this rises to 90%. Where multiple surgeries have been undertaken this falls to 73%. All of the peri-operative investigations have been reviewed and whilst they have a good negative predictive value they are not specific enough to alter practice.

Conclusions: Short courses of parenteral treatment can produce comparable results to previously- published series when treating deep infection after knee replacement. There seems to be a failure rate that is difficult to avoid associated with chronic, multiple revision cases.

Background. Just under 2% of the joint infection work performed over the last 10 years in our institution has involved organisms found in the oropharynx. The issue of antibiotic prophylaxis for dental work in the presence of a joint prosthesis is controversial. However, advanced dental sepsis requires detection and treatment prior to joint replacement.

Methods. Patients from whom non B-haemolytic streptococcal were recovered from revisions of prosthetic joints over the period 1993–2003 were retrospectively reviewed for predisposing factors.

Results. 9 patients had viridans streptococcal infection detected and confirmed by histology and culture at excision arthroplasty. There were 5 total hip joints, 3 knee arthroplasties and 1 shoulder affected. No patient had a history of endocarditis. Two of the patients had previously had multiple revisions. Mean interval in these patients since last surgery was 7.6 years. All patients underwent 2 stage revision procedures. All patients required multiple dental extractions in the interval between 1st and 2nd stage surgery.

On reviewing the patients’ histories further: One patient had reported a broken tooth reported at the time of surgery and been given reassurancethat it was safe to proceed. One patient had an overt dental abscess ongoing for 15 years and one patient had an occult dental abscess revealed on radiology. Two other patients had extensive dental caries with blackened stumps as teeth. Follow-up after antibiotic treatment and revision arthroplasty is limited in these cases but results appear satisfactory at up to five years.

Conclusion. Poor dental care is associated with an increased risk of arthroplasty infection. Looking in the mouth should be a routine part of pre-op assessment prior to primary joint replacement, just as it would be in a cardiac surgery unit. Patients referred from other centres for revision arthroplasty should receive a dental examination if excision arthroplasty cultures yield viridans streptococci.

Aim: To review the early complications associated with staged revision hip Arthroplasty utilising the Biomet antibiotic loaded cement spacer.

Method: We report on 80 consecutive staged revision hip replacements using the Biomet antibiotic loaded cement system in our institution over 3 years (1999–2002), performed by three consultant surgeons, with a minimum 1 year follow up.

Results: Our patients had an average age of 68 (range 48–90) years, with an equal sex distribution.

The median time between the first and second stage was 147 (range 50–619) days.

Fractures of the Biomet antibiotic loaded acrylic spacer occurred in 11% revisions when associated with an increase in time between stages and there was a 7% dislocation rate.

Patients did not receive a revision prosthesis in 19% cases and had early recurrent sepsis following their two stage procedure in 6%. Three patients had a single episode of dislocation of their revision hip prosthesis within a month postoperatively. Two patients had a proximal DVT and one patient had a pulmonary embolus. The mortality within eight weeks was 7%, rising to 10% within a year. This may be related to patient sepsis and comorbidities or the energy expenditure required to mobilise following a first stage procedure that we have analysed.

Conclusions: The risks of staged revision hip surgery for infection are substantial when considering the time involved, the energy expenditure required to mobilise following a first stage, the possibility of not achieving a revision hip prosthesis and the mortality rate.

The Biomet antibiotic loaded cement system articulates and maintains soft tissue length in the majority of patients for the duration required between stages.

The use of distal femoral centralising devices has been advocated in order to achieve an even cement mantle. This has been shown to improve femoral component survival but it is recognised that the presence of voids in the mantle has a deleterious effect on the mechanical strength of cement at laboratory testing and in terms of implant survival. The effect of centralising devices on the mantle in relation to the timing of stem insertion has not previously been investigated.

The purpose of this study is to assess the quality of the cement mantle in artificial bone using a polished taper stem with centralisation inserted at different stages of cement cure time and using different cements.

Three cement types were studied, 45‘saw bone’ models were used. The cementation was carried out in an operating theatre at constant temperature of 23.2Ê°C. The cement was mixed according to the manufacturers instructions and pressurised. Early, intermediate and late stem insertion times were determined for each cement type. The late group included stems with and without centralisers. Video recordings of the stem cement interface were made with a 4 mm endoscope after stem removal. Large cement mantle defects were noted in the ‘with centraliser’ group in 7 out of 15 late insertion times and all had small defects in the mantle. None of the ‘without centraliser’ group had cement mantle defects.

Based on our results we advise surgeons to be very aware of the timing of stem insertion when using centralisers.