Cervical Klippel-Feil syndrome progressing to myelopathy following minor trauma

Klippel-Feil syndrome (KFS) is a rare disease with a clinical triad of low posterior hairline, short neck, and limited neck motion. Frequent fusion of two or more cervical vertebrae resulting from a congenital segmentation defect can lead to adjacent level hypermobility, instability, and even neurologic symptoms that require surgical intervention. However, surgical results in adults with KFS with concomitant atlantoaxial subluxation and cervical spinal stenosis have not been reported. We report a 58-year-old man with complaints of an unsteady gait, general weakness, and clumsiness in both hands for 6 months. Deep tendon reflexes in both knee joints were increased, with a positive Babinski sign. Bladder and sphincter function were intact. Radiographic findings included C2–C7 congenital fusion with atlantoaxial subluxation and spinal cord compression. He was treated with posterior occipitocervicothoracic fusion, instrumentation, and posterior decompression with a partial craniectomy under the diagnosis of cervical myelopathy. Postoperatively, the neurologic deficits improved without any complications, although bilateral rod breakage was noted at consecutive outpatient department (OPD) follow-ups. He recovered well with residual left hand numbness.