Atraumatic avulsion of the distal iliopsoas tendon: an unusual cause of hip pain

Abstract

While uncommon, isolated avulsion fractures of the lesser trochanter occur in children and adolescents prior to the fusion of this apophysis as a result of athletic activities. In the elderly, isolated fractures of the lesser trochanter are rare but can occur as a result of trauma. They have been identified in patients with primary or secondary bone malignancies, which were previously considered pathognomonic for metastatic disease. In the absence of trauma, weakening of the bone due to systemic disorders such as osteoporosis or osteomalacia chronica renal failure may also be responsible. Diagnosis may be difficult with physical examination and radiographs alone. This case report details this rare fracture in 2 patients suffering from debilitating chronic disease. Patient 1 was a 30-year-old woman with an 18-year history of type 1 diabetes mellitus, a 6-year history of end-stage renal disease, hypertension, hypothyroidism, peripheral vascular disease, and a 3-year history of systemic lupus erythematosus with antiphospholipid syndrome treated with warfarin. Patient 2 was a 66-year-old woman with a history of type 2 diabetes mellitus, peripheral neuropathy, obesity, chronic obstructive pulmonary disease, gout, hypertension, and chronic neck and low back pain. Both were assessed with magnetic resonance imaging following physical examination, which revealed atraumatic avulsion of the distal iliopsoas tendon from the lesser trochanter. Following retraction of the iliopsoas tendon, the patients were treated with conservative therapy and anti-inflammatory medication. These 2 cases broaden the range of patients for whom spontaneous avulsion of the distal iliopsoas tendon should be considered in the differential diagnosis.