Pain due to bone insufficiency as a symptom heralding femoral neck fracture.

Although falls are a major factor in the occurrence of femoral neck fractures, their type and frequency have not been studied in detail. A few case-reports have demonstrated that bone insufficiency can lead to femoral neck fracture and that some falls occur as a result of acute pain preceding the fracture. Estimations of the proportion of femoral neck fractures due to bone insufficiency have ranged from 3% to 24%. We conducted a clinical study of 51 patients with recent femoral neck fractures (46 women and 5 men; mean age, 80.6 +/- 9.3 years). Of the 38 patients who fell from the standing position, three (5.9%) experienced acute pain before the fall. Five patients (9.8%) reported trivial trauma and eight (15.7%) no trauma. Twenty-three patients (45.5%) had hip pain during the weeks preceding the fracture; in 20 cases, the pain was located only to the hip that was subsequently fractured. Features associated with spontaneous fracture were pain during the preceding weeks (7/8; p<0.01), gradually worsening pain (6/7; p<0.02), pain in the inguinal or crural area (6/7), and recent onset of pain (< 3 months) (5/7). We believe that the incidence of bond insufficiency as a cause of femoral neck fracture has been substantially underestimated as a result of diagnostic difficulties and of the usually moderate severity of prefracture pain. Improved knowledge of prefracture symptoms provided by a prospective study may allow appropriate treatment by elimination of weight-bearing, avoiding a substantial number of femoral neck fractures.