Calcium crystal deposition in the ligamentum flavum of the cervical spine.

This article reports eight patients who underwent posterior decompressive surgery for myeloradiculopathy caused by calcium crystal deposition in the ligamentum flavum of the cervical spine. All were women with an average age of 72 years and showed neurologic improvement postoperatively. Four patients had diabetes mellitus, and knee meniscus calcification on radiographs were noted in four patients. The ligamentum flavum of C5-6 and C6-7 were sites frequently involved. Crystallographic examination confirmed resected deposits as calcium pyrophosphate dihydrate crystal in all patients and additional hydroxyapatite crystal in two. Histology confirmed marked degeneration in elastic fibers about the calcium deposits. This pathologic condition is possibly spinal manifestation of systemic calcium crystal deposition disease.