Surgical Management of Spinal Disorders in People with Mucopolysaccharidoses

Mucopolysaccharidoses (MPS) are a group of inherited, multisystem, lysosomal storage disorders involving specific lysosomal enzyme deficiencies that result in the accumulation of glycosaminoglycans (GAG) secondary to insufficient degradation within cell lysosomes. GAG accumulation affects both primary bone formation and secondary bone growth, resulting in growth impairment. Typical spinal manifestations in MPS are atlantoaxial instability, thoracolumbar kyphosis/scoliosis, and cervical/lumbar spinal canal stenosis. Spinal disorders and their severity depend on the MPS type and may be related to disease activity. Enzyme replacement therapy or hematopoietic stem cell transplantation has advantages regarding soft tissues; however, these therapeutic modalities are not effective for bone or cartilage and MPS-related bone deformity including the spine. Because spinal disorders show the most serious deterioration among patients with MPS, spinal surgeries are required although they are challenging and associated with high anesthesia-related risks. The aim of this review article is to provide the current comprehensive knowledge of representative spinal disease in MPS and its surgical management, including the related pathology, symptoms, and examinations.