Spinal Stenosis Due to Hypertrophy of the Ligament Flavum with Monosodium Urate Deposits

Park, Jong Beom; Kim, Seung Gey; Choi, Woo Sung; Maeng, Lee So; Chae, Jong Woo; Chang, Han

Abstract

Deposition of monosodium urate crystal in joints and periarticular soft tissue is regarded as one of the characteristics of chronic gouty arthritis. In spine, however, only nineteen cases of tophaceous deposits have been reported to date suggesting the rarity of clinical symptoms secondary to involvement of spine. Authors report a case of spinal stenosis due to hypertrophy of ligament flavum with monosodium urate deposits. The patient was 65 years of age with chronic gouty arthritis who underwent a decompressive laminectomy at L4-5. At surgery, hypertrophied ligament flavum that was covered with chalky amorphous materials was noted without any evidence of radiologic features. Microscopically, a portion of ligament flavum had been focally destoryed by amorphous material deposits that were surrounded by a thin layer of mononuclear and giant cells along with occasional sprinkling of chronic inflammatory cells and negative birefringence on polarizing microscopy.