Osteochondroma arising from posterior superior iliac spine: A case report of unusual cause of low back pain

Abstract

Low-back pain is the most common symptom encountered in orthopaedic spine out-patient practice. In young adults, the usual causes are soft tissue injuries, myofascial pain, annular tear of the intervertebral disc, sacroiliitis and spondyloarthropathies. We report a case of 20-year-old skeletally mature male presenting with chronic low back pain who was treated symptomatically elsewhere. He presented to us for second opinion and upon clinical assessment, he was diagnosed to have osteochondroma arising from the right postero-superior iliac spine. Osteochondromas are osteo-cartilaginous benign tumour with 1% malignant potential seen in adolescents and young adults. They usually arise from the metaphysis of long bones around the knee and occasionally reported in humerus, spine and pelvis. These lesions are mostly asymptomatic and found incidentally. En-bloc excision of the tumor is recommended for symptomatic osteochondromas. Clinicians should be aware of atypical pelvic osteochondromas which can present as extra-spinal cause of chronic low back pain.