Scintigraphic evaluation of transtrochanteric rotational osteotomy for osteonecrosis of the femoral head. Comparison between scintigraphy, radiography and outcome in 34 patients.

Scintigrams and radiographs of 36 femoral heads in 34 patients before and after Sugioka's transtrochanteric rotational osteotomy for osteonecrosis of the femoral head were investigated prospectively. Patients were followed for more than 3 years after the operation. The patterns of early scintigrams made within 3 months of the operation were classified into four categories. All 4 patients with a large cold area evidenced collapse within 1 year despite good recovery of the weight-bearing surfaces immediately after operation on conventional radiograms. Twenty-two hips with no cold area in the femoral head did not demonstrate collapse. Femoral head collapse after rotational osteotomy can be predicted by early postoperative bone scintigraphy.