Acetabular cup size trends in total hip arthroplasty

ARTICLE HIGHLIGHTS

Research background

To the authors knowledge this is the first study examining total hip arthoplasty experience and the relationship with acetabular cup size. Other facets of arthroplasty learning are documented however the trend towards ever decreasing cup sizes has not been previously described in the literature.

Research motivation

The motivation for this study was derived from noting a trend towards smaller acetabular cup sizes by one of the arthroplasty surgeons in our institution. We wanted to investigate if this observation was in fact correct and if so identify the underlying reasons.

Research objectives

The main objective was to record acetabular cup size used against time. This was completed by means of chart review. Future research by means of a prospective trial would benefit from standardization in cup size used.

Research methods

The log books from our elective theaters were cross checked with the national hip database. Acetabular cup sizes used were recorded for each surgeon. Logistic regression was then used to assess the trend against time.

Research results

We found experience in hip arthroplasty predicts an ever-decreasing acetabular cup size. The main unresolved question is why does this trend exists? This retrospective study also highlights that the trend for males appears to be more pronounced. This finding was unexpected and again the exact reason for this can only be speculated at this stage.

Research conclusions

This study proposes that even despite being fully trained in hip arthroplasty, a trend exists to ever decreasing acetabular cup sizes for arthroplasty surgeons.

Research perspectives

Future research should be targeted at investigating if these smaller acetabular cups result in improved clinical outcomes and also at the underlying reasons for this trend.