How to properly correct and to assess acetabular position: an evidence-based approach.

BACKGROUND

The periacetabular osteotomy (PAO) described by Ganz and colleagues is currently used to reorient the acetabulum in cases of acetabular dysplasia and malrotation. It is considered a technically difficult procedure with a formidable learning curve. The purpose of this paper is to answer the following questions: (1) What are the current indications and technique of the PAO? (2) What is the available biomechanical evidence that supports acetabular reorientation? (3) What measures are established for intraoperative assessment of acetabular correction?

METHODS

A systematic literature review of Pubmed, CINAHL, and Cochrane Library was performed for selected keywords. A total of 400 abstracts were reviewed and papers chosen if they met selection criterion.

RESULTS

Thirty-eight papers were reviewed. The clinical indications for PAO are consistent among retrospective reviews. There is a growing body of in vitro and finite element data that supports the concept of acetabular reorientation. There are no prospective clinical data that correlate clinical outcome scores with measures of acetabular reorientation.

CONCLUSIONS

Although PAO is considered the standard of care for the correction of acetabular malrotation and dysplasia, magnitude of correction and assessment of correction is based upon conceptualized ideal acetabular anatomy. Further, basic biomechanical research and clinical outcomes research is necessary to help optimize acetabular position following reorientation.