C5 palsy after anterior decompression and fusion of cervical spine

English Keywords:C5 palsy  Cervical spine  Anterior surgery  Decompression

English Abstract:

  【Abstract】 Objectives: To observe the clinical features and prognosis of C5 palsy after anterior decompression and spinal fusion of cervical spine. Methods: Between May 2007 and January 2012, 121 patients without deltoid weakness underwent anterior cervical decompression and spinal fusion which included the level of C4/5. The patients included 65 males and 56 females with a mean age of 64.2 years. The diagnoses were cervical spondylotic myelopathy(45 patients), cervical spondylotic myeloradiculopathy(32 patients) and cervical ossification of posterior longitudinal ligament(44 patients). The grade of manual muscle test(MMT) of deltoid and biceps brachii, the diameter of the C4/5 foramen on CT and the high signal changes in the spinal cord on T2-weighted MRI were measured and evaluated. In the present study, C5 palsy was defined as a deterioration of deltoid muscle by at least 2 grades in a standard MMT without aggravation of lower extremity function. Results: 6 patients developed C5 palsy, 1 of them suffered from bilateral weakness of deltoid and biceps brachii and 5 of them from unilateral. All presented with pain or numbness on the C5 enervation region. One of them underwent the decompression of C4/5 and another one underwent the corpectomy of C5, the rest of them underwent anterior multiple segment decompressions. The high signal changes in the spinal cord on T2-weighted MRI were found in all 5 patients suffering from C5 palsy. All patients were followed up for 1-4 years. The grade of MMT recovered to 4-5 degree in 8 months after surgery, two of them recovered to 4 degree with a mean period of 4 months(range, 1-8 months). The JOA score improved from 10.8±1.1 preoperatively to 16.2±1.3 postoperatively, with significant difference. The rate of satisfaction of patients was 40%-70%(mean 55%). The diameter of the C4/5 foramen in C5 palsy and no palsy was 2.86±0.28mm and 3.18±0.39mm respectively, which showed no statistical difference. In 53 cases with the diameter of C4/5 foramen less than 3.0mm, 4 cases developed C5 palsy. Only 2 cases in 68 cases with the diameter of C4/5 foramen more than 3.0mm developed C5 palsy. Among 121 cases， less than 2 level decompression had the rate of C5 palsy of 2.4%(2/82), while 3 level decompression had the rate of 10.2%(4/39), which showed significant difference（P＜0.05）. Conclusions: C5 palsy is the possibly complication after the anterior cervical decompression, which has a good prognosis. Corresponding conservative intervention is effective.