Fibrous dysplasia of thoracic and lumbar spine: A case report

Introduction Fibrous dysplasia (FD) is a rare genetic disease characterized by development of dysplastic bone tissue leading to pain, deformities and compressive complications. Spinal involvement is rare particularly for the polyostotic form. Case report Herein, we present a case of 52-year-old man presented with isolated low back pain who received non-steroidal anti-inflammatory drugs (NSAIDs) with partial pain relief. On examination, the thoracic and lumbar spines were tender. Lumbar spine movements, attested by Shober’s test and finger-to-floor test, were limited. There was no radicular pain and neurological examination was normal. The erythrocyte sedimentation rate was 20 mm/1st hour, C- reactive protein 2 mg/l and white blood cell count, serum calcium, phosphorus, alkaline phosphatase and parathormone were normal. Plain x-ray lumbar and thoracic spine and hips were normal. X-ray cervical spine and peripheral bone showed no lesions. Computed tomography (CT) and magnetic resonance imaging showed multiple osteolytic lesions with ground-glass opacity and sclerotic rims of thoracic and lumbar (L1 and L2) spine. Investigations to rule out malignancy or infections were negative. CT guided biopsy of a lumbar vertebra was performed and showed the presence of abnormal fibrous matrix surrounding an irregular shaped immature bone. The diagnosis of polyostotic FD of the spine was made. Zoledronic acid infusion was introduced and the patient felt better thereafter with no additional osteolytic lesions or new pain localization reported for 2 years on follow up. Conclusion Thoracic and lumbar spine FD is a rare localization that should be considered in the differential diagnosis of back pain.