Can Multilevel Anterior Cervical Discectomy and Fusion Result in Decreased Lifting Capacity of the Shoulder?

OBJECTIVES: To investigate the upper-extremity abduction, and lifting limitations and associated factors after anterior cervical decompression and fusion. METHODS: A total of 117 patients who underwent anterior cervical decompression and fusion for cervical spondylosis were assessed retrospectively. Their upper-extremity abduction and lifting capacity after operation and manual muscle test grade for deltoid muscle strength and its sensory status were recorded. In addition, spinal cord function (Japanese Orthopaedic Association and Neck Disability Index scores) and C4-5 intervertebral height (radiographs) were assessed. Finally, high signal and ossification of posterior longitudinal ligament were observed by T2 magnetic resonance imaging and computed tomography, respectively. RESULTS: Seven individuals had a decrease in muscle strength, with 2 patients also exhibiting sensory defect. Six individuals had bilateral weakness of deltoid and biceps brachii and 1 of unilateral. After 8-16 months of follow-up, the abduction function and lift capacity were restored. The manual muscle test grade recovered to 5 and 4 degrees, respectively, in 6 and 1 patients. Two patients remained with sensory defect. The mean recovery time 19.7 days on average, and Japanese Orthopaedic Association scores significantly improved. Among the 117 patients, less than 2-level decompression showed upper-extremity function limitations in 1 of 67 (1.5%), whereas more than a 3-level decompression resulted in greater rate in 6 of 50 (12%), a significant difference (P < 0.05). No significant difference was obtained in C4-5 intervertebral heights, as well as for rates of C3-5 high signal area in magnetic resonance imaging. CONCLUSIONS: The rate of upper-extremity abduction and lifting limitation after anterior cervical decompression and fusion is low, indicating a good prognosis after active treatment.