The learning curve for the direct anterior approach for total hip arthroplasty: a single surgeon's first 500 cases.

BACKGROUND: Concerns arise over the early complications encountered during the learning curve for the direct anterior approach for total hip arthroplasty.The purpose of this study is to examine the learning experience of a single surgeon in adapting this approach.

METHODS: The 1st 500 primary total hip arthroplasties are reviewed. The patients were evaluated out to 3 months. Rates of major complications, reoperations, periprosthetic fractures, heterotopic ossification, leg length discrepancies and lateral femoral cutaneous nerve deficits were identified for each of 100 patients.

RESULTS: The major complication rate decreased from 5% to 2% throughout the series. Reoperation rates fluctuated from 2% in the 1st 100 cases to 3% in the 4th 100 cases to 1% in the 5th 100 cases. The periprosthetic fracture rate decreased from 9% to 2%.

CONCLUSIONS: The incidence of heterotopic ossification declines throughout the series and is attributed to changes in irrigation technique and quantity. The incidence of major complications decreases with increasing experience. The most dramatic improvements occur after the 1st group of 100 cases.