Deceptive low back pain and pseudoradicular signs in avascular necrosis of the femoral head.

Background. Deceptive low back and buttock pain, especially at night, is often the main subjective symptom in necrosis of the femoral head. During this period, limitations of the final phase of the range of hip movement (especially inward rotation and abduction) constitute an objective symptom. Careful examination of both hip joints typically reveals asymmetry in the range of movement. Scintigraphy is decisive for the diagnosis. The real source of the pain is in the hip, but their common location in the lumbosacral area and the buttocks often leads to mistaken diagnosis. Material and methods. In the Orthopedics, Traumatology and Rehabilitation Clinic in Lublin 86 patients (41 women, 45 men), ranging in age from 19 to 69 years (mean age 42) were treated for necrosis of the femoral head (116 hips). Disturbances of blood supply to both femoral heads were found in 30 cases. Results. Ineffective treatment of 18 patients (20.9%) by neurologists and neurosurgeons, who performed unnecessary discectomies in 4 patients, delayed diagnosis of necrosis in 26 femoral heads (22%). The errors were discovered only in the third or fourth phases of the disease, when the only effective remaining treatment is hip arthroplasty. Conclusions. In patients with low back and buttock pain, examination of the range of hip movement is indispensable. If even a slight limitation of the range of movement is detection, hip x-rays should be made in two projections. If there is suspicion of early radionegative disturbances of the blood supply to the femoral head, scintigraphy is decisive.