Noncalcified Hypertrophic Ligamentum Flavum Causing Severe Cervical Stenosis and Myelopathy: Case Report and Review of the Literature.

Background: Calcified hypertrophic ligamentum flavum is a known entity that causes myeloradiculopathy of the cervical, thoracic, and lumbar spine and is seen more commonly in Asian populations. Noncalcified hypertrophic changes are less common and may mimic other epidural space-occupying lesions.

Case Description: A 59-year-old woman presented with progressive myelopathy, and imaging studies were consistent with an epidural space-occupying lesion from C4-T3. The patient underwent posterior cervical decompression and fusion with instrumentation. Pathology specimens revealed noncalcified hypertrophic ligamentum flavum.

Conclusions: To our knowledge, noncalcified hypertrophic ligamentum flavum causing progressive cervical myelopathy has never been reported in the English literature. This entity should be considered in cases with epidural masses causing progressive myelopathy.