Efficacy of anterior oblique keyhole approach for cervical discogenic disease

The anterior oblique keyhole approach does not require fusion manipulation, and is a useful surgical method that is less invasive for the treatment of discopathy of the cervical spine. This approach can be used even in the treatment of multilevel lesions. However, long-term follow-up study is required to determine the efficacy of this technique. We report 52 cases surveyed more than one year. The mean follow-up period was 36 months. The patients consisted of 30 men and 22 women with an average age of 58.1 years old(33-83 years old). The levels treated with this procedure involved C₃/₄, C₄/₅, C₅/₆, C₆/ ₇, and C₇/T₁. Pathology included: cervical disc hernia, 41 cases; cervical spondylosis, 10 cases; and ossification of the posterior longitudinal ligament, 1 case. The numbers of intervertebral spaces treated with this procedure were 1 (32 cases), 2 (17 cases), or 3 (3 cases). The neurological symptoms included radiculopathy alone in 34 cases, myelopathy alone in 10 cases, and both radiculopathy and myelopathy in 8 cases. Postoperative neurological evaluation was performed in accordance with the Neurosurgical Cervical Spine Scale. Cervical spine computed tomography and magnetic resonance imaging were used for postoperative and follow-up neuroradiological evaluation. The average improvement rate was 86.4% at one month after surgery, and it remained at this level even one year after surgery. We divided the cases into two groups, which were the cases represented with the radiculopathy alone (group 1) and the cases represented with the radiculopathy and myelopathy, myelopathy alone (group 2). Excellent or good outcome was observed in 88.9% of cases in group 1 and in 72.7% of cases in group 2. No patients had postoperative cervical spine instability. The width of anterior decompression was 6 to 12 mm with an average of 8.7 mm. The average hospitalization period was 10 days. There was one case showed spinal cord injury as the postoperative complication. The patients domonstrated no limitation of activity the day after surgery and showed the preservation of the neck motion postoperatively because the procedure did not include disc fusion. This method is less invasive and can be performed in elderly patients to improve QOL.