Multilevel thoracic and lumbar ligamentum flavum ossification in an achondroplasic—a rare presentation

Abstract

Introduction: Achondroplasia is a rare autosomal dominant condition characterized by stenosis in spinal canal. Multilevel Ossification of the ligamentum flavum in the spine is a rare occurrence which too can contribute to stenosed canal. Case presentation: We report a case of an Indian achondroplasic dwarf with multilevel ossification of ligamentum flavum (OLF) at thoracic and lumbar segment. She presented in the outpatient department with bilateral weakness in legs with complete foot drop on the left side and was non-ambulatory. She was managed surgically by instrumentation with multiple interbody fusions with wide decompression and excision of OLF. The patient responded well to the surgery and became a walker after 2-year follow-up. Discussion: Achondroplasic patients may present rarely with multiregional and multilevel OLF. It is important to identify them preoperatively so as to have good surgical outcome. Wide laminectomy, removal of the ossified ligament, and fusion with instrumentation resulted in the improvement of the patient’s neurological symptoms and functions.