The Journal of Bone and Joint Surgery, Vol 65, Issue 6 786-796, Copyright © 1983 by Journal of Bone and Joint Surgery, Inc
Post-traumatic avascular necrosis of the femoral head predicted by preoperative technetium-99m antimony-colloid scan. An experimental and clinical study
JH Turner
We used technetium-99m antimony colloid to visualize the bone marrow of the
head of the femur within twenty-four hours after interruption of the blood
supply by subcapital osteotomy and section of the ligamentum teres in
thirteen rabbits and within twenty-four hours after a subcapital fracture
in thirty patients. Of the rabbits, all showed loss of marrow radioactivity
over the affected femoral head. Bone-imaging with technetium-99m methylene
diphosphonate, in contrast, failed to demonstrate any abnormality in the
avascular head of the femur for as long as forty-eight hours after
osteotomy. This difference between the marrow scan and the bone scan was
attributed to earlier loss of function in the marrow cells than in the
osteocytes. The thirty patients who had a preoperative scan within
twenty-four hours after sustaining a subcapital fracture were treated by
internal fixation with a Richards screw and plate and were followed for as
long as two years, or until the patient died or radiographs showed evidence
of avascular necrosis. The preoperative technetium-99m antimony-colloid
activity in the head of the fractured femur was normal in sixteen patients
and absent in fourteen; two of the fourteen had no activity in either hip,
which precluded assessment of the fractured hip in these patients. In
fifteen of the sixteen hips, preservation of the uptake in the marrow of
the head of the fractured femur preoperatively predicted normal healing.
Late segmental collapse developed in the remaining hip. In eleven of the
twelve patients who had loss of marrow activity in the femoral head
preoperatively, avascular necrosis developed within two years. One patient
was asymptomatic at two years, with no evidence of necrosis. The two
patients who had no marrow activity in either hip both had avascular
necrosis within one year after surgery.