THE EFFECT OF REDUCING INCISION SIZE ON COMPONENT ORIENTATION IN TOTAL HIP ARTHROPLASTY

Abstract

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.