C5 palsy after decompression surgery for cervical myelopathy - Review of the literature

Study Design. A literature review was conducted to integrate and compile available reports on postoperative C5 palsy. Objectives. To review the clinical features, possible pathogenesis, and procedures for treatment and prevention of postoperative C5 palsy as a complication of surgery for cervical compression myelopathy. Summary of Background Data. Although postoperative C5 palsy develops in approximately 5% of patients after decompression, surgery of the cervical spine, its pathogenesis and the options for prevention and treatment remain unidentified and many controversies exist. Method. We reviewed and analyzed papers published from 1986 to 2002 regarding C5 palsy,as a postoperative complication. Statistical comparisons were made when appropriate. Results. Postoperative C5 palsy is reported to occur in an average of 4.6% of patients after surgery for cervical compression myelopathy. No significant differences were noted between patients undergoing anterior decompression and fusion and laminoplasty, nor were distinctions apparent between unilateral hinge laminoplasty and French-door laminoplasty, or between cervical spondylotic myelopathy and ossification of the posterior longitudinal ligament. Two theories were put forth to account for the pathogenesis of C5 palsy: nerve root injury and segmental spinal cord disorder. Neither of these hypotheses has been consistently supported and evidence to refute each hypothesis can be found in the literature. Recently, surgeons have advocated foraminotomy, combined with laminoplasty to preventor treat C5 palsy, but further studies into the,efficacy of this procedure are needed. Although patients with C5 palsy generally have a good prognosis for neurologic and functional recovery, those with severe paralysis require significantly longer recovery times when compared to more mild cases. Conclusion. The incidence of postoperative C5 palsy has been reported at 4.6% after surgery for cervical compression myelopathy and this value has not varied with different surgical procedures or disease etiologies. The pathogenesis of postoperative C5 palsy remains unclear at the present time. Patients with postoperative C5 palsy generally have a good prognosis for functional recovery, but the severely paralyzed cases required significantly longer recovery times than the mild cases.