Femoral subtrochanteric insufficiency fracture after long-term bisphosphonate therapy masked from foraminal stenosis of lumbar spine: A case report

ABSTRACT

We present a case of an insufficiency fracture of the subtrochanteric region of the femur in a 78-year-old woman masked by lumbar spinal foraminal stenosis. She complained of pain and a tingling sensation in the anterior and lateral side of the right thigh, leg, and ankle. Selective transforaminal epidural (L4-5, Rt.) and caudal block were done under the diagnosis of lumbar foraminal stenosis. The tingling sensation was completely relieved, but the pain was not completely relieved. The patient had been receiving bisphosphonate therapy for 6 years under the diagnosis of osteoporosis. We performed magnetic resonance imaging, which showed a unicortical break line and marrow edema around the hypertrophied area. Surgery was done. In cases with incomplete relief of the pain in the thigh following epidural block, physicians should keep in mind the possibility of femoral insufficiency fracture in patients who have received long-term bisphosphonate therapy.