脊柱杂志

Surgical Management of C5 Palsy Resulting from Posterior Spinal Decompression for the Treatment of Cervical Spondylotic Myelopathy

Abstract

Khaled Saoud, Amr El-Shehaby and Ayman El-Shazly

Objective: To assess the feasibility of anterior cervical procedures in the treatment of C5 palsy occurring after posterior cervical decompression procedures done for the treatment of cervical spondylotic myelopathy.

Introduction: In this study we hypothesized that anterior cervical decompression would benefit these patients through widening the cervical foramen, directly by rongeurs and drills and indirectly by placing an intervertebral spacer (cervical cage). The aim of the study is to assess whether a more proactive approach would benefit these patients.

Materials and methods: Between January 2005 and September 2011, 200 posterior cervical procedures have been done by the authors, for the treatment of cervical spondylotic myelopathy (CSM). The procedures done were laminectomy with or without instrumentation. Forty cases developed C5 palsy postoperatively (20%). 20 cases (50%) presented immediate postoperatively and the rest presented during the first week postoperatively. All the cases started a course of conservative treatment of steroids, analgesics and physiotherapy. Thirty patients (75%) improved on conservative treatment. Ten patients did not improve after more than one year of conservative management. Two cases had a single level anterior cervical discectomy and cage fusion (ACDF), 3 cases had single level ACDF with
plate fixation and 3 cases had 2 levels ACDF with plate fixation. Two cases had 3 levels ACDF with interbody fusion and plate fixation. The operative choice was made in order to increase the lordotic curve and the foraminal diameter.

Results: Immediately postoperatively all patients had improved radicular pain. Assessment of the motor power was made immediately postoperative and 3 months afterwards with continuous physiotherapy. There was no change in the C5 palsy in all cases on the immediate postoperative examination, whereas all cases showed improvement of at least 2 grades in the 3 months postoperative visits. All patients at the final follow up had an MMT (Manual Muscle Test) grade of at least 3. Six patients reached an MMT grade of 4 or more. One case had recurrent myelopathy 9 months after 3 levels ACDF and fixation. His MRI showed adjacent segment degeneration at a higher level and had led to myelopathy. He improved on conservative treatment. Two cases died during follow up period: one at 10 months postoperatively from complications of massive myocardial infarction and the other one 15 months postoperatively from
bronchogenic carcinoma diagnosed 7 months after surgery.

Conclusion: Postoperative C5 palsy following posterior decompression for cervical spondylotic myelopathy is not an uncommon occurrence and the majority of cases will respond to conservative treatment. Anterior decompression procedures may offer a safe and effective solution for those few patients who do not respond to a prolonged period of conservative management.