Aim: To develop a device to improve the preparation of morcellised bone graft for use in revision arthroplasty surgery.

Background: Washing morcellised graft prior to impaction has been shown to improve the stability of the graft after impaction. By removing the cellular debris the chance of contamination is potentially reduced.

Methods: A readily available domestic appliance was identified which met the requirements of being able to contain the graft whilst allowing free drainage of the pulsed lavage solution. This hand held potato masher has an all metal construction with few moving parts and is therefore easily cleaned and sterilised between cases. The numerous perforations in the receiver of the masher ensure that the lavage solution rarely backs up and also that all of the cellular debris is washed through effectively.

Results: This device has been in regular use in this institution over the last two years. It allows a no touch technique for the preparation of morcellised graft in complex cases that require replacement of the bone stock.

This poster will demonstrate pictorially the technique for graft preparation and the quality of the prepared graft that can be obtained.

Aim: A radiological review to assess component orientation in a consecutive series of primary total hip replacements performed by a high volume hip surgeon through either a standard or reduced size incision.

Background: Using a posterior approach and standard instrumentation the senior author has reduced his incision size in selected patients over the last 2 years. There is no fixed definition of incision size in this series, incision sizes fall between 10 and 15cm in most cases. The implication is that deliberate efforts were made to limit the incision length compared to a routine exposure at the start of surgery.

Method: From the operative records kept for the senior author a series of 48 patients was identified, with equal numbers having reduced or standard incisions. A radiological review was performed looking at the cementation, leg length and component orientation in both the AP and lateral planes.

Results: In the AP plane there was no significant difference in the alignment of the components. In the reduced incision group an increased number of stems were directed from anterior to posterior on the lateral x-rays.

The quality of the femoral cement mantles was significantly better in the standard incision group (75% Barrack A vs. 50% Barrack A)

On the acetabular side the components were better positioned and orientated in the small incision group but cementation was again improved in the standard incision group.

Conclusions: Reducing incision size does have an influence on cementation and the positioning of components during hip arthroplasty.

The orientation and cementation of components in both study groups would be considered acceptable in the majority of cases.

The authors recommend small audit studies of this nature as a way of providing ongoing feedback on the quality of their surgery thereby allowing improvements to be made to their surgical technique.

Background: Infection in total joint replacement remains one of the most devastating post operative complications. The majority of these infections are still caused by organisms normally found on the skin. The use of adhesive wound drapes has become commonplace in orthopaedic surgery but frequently these are detached from the wound edges at the end of surgery allowing contamination of the wound.

Aim: To develop a technique to improve the adherence of wound drapes.

Methods: The first part of this study was to experiment with a number of techniques to prepare the skin preoperatively. We were able to identify that a combination of initial Betadine in alcohol preparation, followed by re-preparation of the operative site with Chlorhexidine in alcohol produced the best combination of drape adherence. In a consecutive series of 100 patients we have used our original technique of preparing the wound for 50 patients followed by a further 50 patients prepared with the new technique.

Results: In the initial patient group all of the adhesive drapes were detached enough to expose the skin edges in at least one part of the wound by the end of the surgical procedure. With the new technique we have had no detachments of the adhesive drape.

There have been no complications or skin reactions related to this method of skin preparation. There has been no significant difference in the incidence of early post operative wound infection.

Conclusion: This technique of operation site preparation provides an excellent means of preventing detachment of adhesive wound drapes. We have found it reliable, safe and effective to date and it adds little to the overall procedure time. We recommend this technique as a way of ensuring that the skin edges remain covered throughout primary and revision procedures.

We present the case of an elderly lady who was treated surgically as an infant for osteomyelitis of the left distal femur. Throughout the whole of her adult life she describes episodes where the thigh has become more painful and warm followed by a watery discharge from a sinus on the upper medial aspect of the thigh. This sinus has discharged at least weekly up until the present day. No further surgery has been performed on the proximal femur since childhood.

Almost 10 years ago the patient presented with symptoms of osteoarthritis in the left hip. A total hip replacement was performed at that time without any further active measures aimed at eradication of the osteomyelitis.

Despite obvious concerns of the possibility of exacerbating the osteomyelitis and developing pan femoral disease this has not been the case. The hip replacement is symptom free, stable and there are no signs of infection clinically or radiologically.

Conclusions: Whilst we would not immediately recommend this course of action; the surgical treatment of long bone osteomyelitis if an arduous procedure for both patient and surgeon with high recurrence rates. This case demonstrates that in low demand elderly patients it may be possible to implant a hip replacement.

Aim: To review the study size and requirements of studies looking at factors affecting outcome following total hip arthroplasty.

Background: The orthopaedic literature is full of claims that new products out-perform older ones, cemented and un-cemented components are equal, cementing grades and mantles are all important and that component orientation is vital to longevity. We are also aware of patients who have performed well despite having numerous adverse features to their joint replacements.

We have searched the available literature for factors that have been implicated in the survival of hip replacements. We have used these to determine the likely study sizes required to provide meaningful data.

Method: We identified over 50 variables that have been implicated in the survival of hip replacements. Assuming all of them to be of equal relevance the study size required for multivariate analysis to be possible would be in excess of 50000. Some of these variables are less likely to be of great significance and this number could potentially be reduced to 25–30000.

Discussion: Because total hip replacement has a greater than 90% success rate at 10 years in nearly all series this makes the numbers required for multivariate analysis much larger. Individual factors affecting survival will be difficult to identify unless large series are considered.

Conclusion: The only way to reduce the numbers required for meaningful studies is to increase the matching of as many variables as possible to ensure that investigators conclusions are valid in the majority of small series orthopaedic studies.

The use of Joint Registers is likely to be the only way of obtaining the volume of data required to detect individual factors affecting survival. Care will still need to be taken interpreting this data as there are still numerous variables which are not accounted for in the Joint Register.