Predictive value of early scintimetry in intracapsular hip fractures. A prospective study with regard to femoral head necrosis, delayed union and non-union.

In 84 patients with an intracapsular hip fracture, early technetium-99m methylene diphosphonate (99mTc-MDP) scintimetry could be carried out preoperatively of in the case of conservative treatments within 72 h after injury. Fifty-four patients were available for a 3-year follow-up. The corrected uptake ratio showed a very high accuracy in predicting secondary dislocation, non-union (NU), delayed union (DU) or femoral head necrosis (FHN) and was far more reliable than the uncorrected uptake ratio. The predictive value of scintimetric follow-up at a 2- or 12-week interval could not reach the same accuracy of early scintimetry in predicting poor outcome. A comparison of follow-up scintimetry after conservative treatment and osteosynthesis showed that the major vascular injury to the femoral head is caused at the moment of the initial trauma and that no additional damage occurs perioperatively with closed reduction and fixation with a Dynamic Hip Screw device. Scintimetry is a useful tool in predicting poor outcome due to FHN and/or NU in the treatment of intracapsular hip fractures.