Study design: This retrospective study involves 26 patients with degenerative cervical myelopathy who were surgically treated by anterior corpectomy, titanium mesh cage (TMC) filled with autogenous bone, and anterior plate +/- posterolateral plate and fusion.
Objectives: This study was conducted to determine the indications, efficacy, and complication rate associated with performing corpectomy to achieve anterior decompression of neural elements or for removing anterior lesions.
Summary of background data: This retrospective study involves patients with degenerative cervical myelopathy who were surgically treated by > or =2-level anterior corpectomy, TMC filled with autogenous bone, and anterior plate +/- posterolateral plate and fusion. The purpose was to evaluate and compare the results in terms of neurologic recovery and function and effectivity of TMC as a structural support.
Methods: Twenty-six patients with degenerative cervical myelopathy who had surgical treatment and average 30 months (range, 24-52 months) follow up were included. The mean age was 64.9 years (range, 55-74 years) and average period between myelopathic symptoms and surgery was 2.8 years (range, 6 months-5 years). Preoperative evaluation of every patient consisted of anterior-posterior, lateral, bilateral oblique, flexion, and extension radiographs, computed tomography reconstructions and magnetic resonance imaging of the cervical spine, Doppler ultrasound of the carotid arteries, vertebral artery magnetic resonance angiography, neurologic examination, and electromyography. Degree of pre- and postoperative myelopathy was determined according to the scoring systems developed by Nurick and Japanese Orthopedic Association (JOA). Twelve patients had a mild balance problem and difficulty while walking but were able to perform their daily activities. Fourteen patients had spastic quadriparesis ambulating on either crutches or with wheelchairs. Of these, 11 experienced bladder disturbance as well. Surgical treatment in 18 patients consisted of anterior decompressive corpectomy, structural TMC, and anterior plate stabilization in 14 patients who had 2-level corpectomy. Posterior plate stabilization without laminectomy was added to this procedure in another 4 patients who had 3- or more level corpectomy. The remaining 8 patients had first laminectomy and posterolateral plate, then anterior corpectomy, TMC, and anterior plate on the same stage. Corpectomy levels were between C3 and T1, and anterior corpectomy, structural TMC, and anterior plating was the procedure that all patients had in common.
Results: Mean sagittal Cobb angle (C2-C7) was 9 degrees (range, 0-23 degrees) before surgery, 17.1 degrees (range, 11-22 degrees) on the third postoperative month, and 16.9 degrees (range, 10-22 degrees) at last follow-up. The difference in sagittal alignment on the third month and last follow up was not statistically significant (P > 0.05). Average preoperative Nurick score was 3.5 (range, 2-5) and JOA score was 7 (range, 1-14). Major and statistically significant neurologic recovery was within the first 3 months, and average Nurick and JOA scores at 3 months were 2 (range, 0-3) and 11 (range, 8-17) (P < 0.001), respectively. All patients had improved neurologic status at final follow up. As confirmed by plain radiographs and computed tomography reconstructions, solid fusion was achieved across the TMC with no settling or migration, and we had no implant-related complication or failure. As major complications, 1 (3.8%) early deep posterior infection developed but responded to early debridement and antibiotics. Also, 3 patients (11.5%) had transient C5 nerve root injury. At final follow up, all patients were able to ambulate without support and maintain their daily activities.
Conclusions: Anterior decompression provides good neurologic recovery in patients with degenerative cervical myelopathy. TMC provides good structural support, and solid fusion can be achieved with TMC and anterior plate (for < or =2-level corpectomy) and/or posterior plate (> or =3-level corpectomy). There is increased risk of C5 nerve root injury when first laminectomy and posterolateral plate stabilization are performed.