Psoas tenotomy and heterotopic ossification after Charnley low-friction arthroplasty.

One hundred twelve cases of Charnley low-friction arthroplasty (LFA), with elevation of the psoas tendon from the lesser trochanter, were reviewed. Twenty-six (23.3%) had heterotopic ossification in that area. No heterotopic ossification was present in 124 cases without psoas tenotomy. Periosteal elevation at the time of tenotomy is a likely cause of psoas heterotopic ossification.