A 15-year-old woman had mucopolysaccharidoses type 4A (Morquio syndrome). Recent neck pain, progressive weakness, and numbness in 4 extremities were described. Physical examination revealed decreased muscle power, increased deep tendon reflex, and positive Hoffman sign. A brain and cervical cord magnetic resonance image was obtained and showed mild atlantoaxial subluxation, odontoid hypoplasia, and thickened soft tissue without contrast enhancement anterior to the cord, which contributed to cervical cord compression (Figure). The patient was later referred to another hospital for surgical intervention.
Li M, Chiu P, Weng M, Lai P. Atlantoaxial Instability and Cervical Cord Compression in Morquio Syndrome. Arch Neurol. 2010;67(12):1530. doi:10.1001/archneurol.2010.308