This is the first published report of a patient with Klippel-Feil syndrome treated with cervical arthroplasty. A 36-year-old man presented with posterior neck pain and myelopathic symptoms. A radiograph demonstrated congenital fusion of the vertebral bodies at C2-3, C4-5 and C5-6. On MRI, the spinal cord was compressed by a protruding cervical disc and bony spurs at C6-7. After anterior discectomy and decompression of the spinal cord at the C6-7 level, the disc was replaced with the Bryan cervical disc system (Medtronic Sofamor Danek, Memphis, TN, USA) to restore normal motion. The absence of adjacent segment degeneration and the preservation of cervical motion were noted 2 years after surgery. Arthroplasty may be performed in selected patients with Klippel-Feil syndrome in order to restore motion and to prevent degeneration of the adjacent segment by reducing hypermobility.