Heterotopic ossification in total hip arthroplasty. The influence of the approach.

The effects of lateral approaches for total hip arthroplasty on heterotopic bone formation were studied in 264 patients with primary osteoarthritis. The Hardinge approach was used in 82 patients, the transtrochanteric approach in 94, and the Liverpool approach in 88. The incidence of heterotopic ossification was 42%. A severe form of bone formation occurred five times more in the Liverpool approach than in other two approaches.