Clinical Challenges and Advances in Cervical Spine Surgery

Introduction: In a multilevel cervical laminoplasty operation for patients with cervical spondylotic myelopathy (CSM), a partial or complete C3 laminectomy may be performed at the upper level instead of a C3 plated laminoplasty. It is unknown whether C3 technique above the laminoplasty affects loss of cervical lordosis or range of motion. Methods: Patients undergoing multilevel laminoplasty of the cervical spine (C3–C6/C7) at a single institution were retrospectively reviewed. Patients were divided into two cohorts based on surgical technique at C3: C3–C6/C7 plated laminoplasty (“C3 laminoplasty only”, N = 61), C3 partial or complete laminectomy, plus C4–C6/C7 plated laminoplasty (N = 39). All patients had at least 1-year postoperative X-ray treatment. Results: Of 100 total patients, C3 laminoplasty and C3 laminectomy were equivalent in all demographic data, except for age (66.4 vs. 59.4 years, p = 0.012). None of the preoperative radiographic parameters differed between the C3 laminoplasty and C3 laminectomy cohorts: cervical lordosis (13.1° vs. 11.1°, p = 0.259), T1 slope (32.9° vs. 29.2°, p = 0.072), T1 slope–cervical lordosis (19.8° vs. 18.6°, p = 0.485), or cervical sagittal vertical axis (3.1 cm vs. 2.7 cm, p = 0.193). None of the postoperative radiographic parameters differed between the C3 laminoplasty and C3 laminectomy cohorts: cervical lordosis (9.4° vs. 11.2°, p = 0.369), T1 slope–cervical lordosis (21.7° vs. 18.1°, p = 0.126), to cervical sagittal vertical axis (3.3 cm vs. 3.6 cm, p = 0.479). In the total cohort, 31% had loss of cervical lordosis >5°. Loss of lordosis reached 5–10° (mild change) in 13% of patients and >10° (moderate change) in 18% of patients. C3 laminoplasty and C3 laminectomy cohorts did not differ with respect to no change (<5°: 65.6% vs. 74.3%, respectively), mild change (5–10°: 14.8% vs. 10.3%), and moderate change (>10°: 19.7% vs. 15.4%) in cervical lordosis, p = 0.644. When controlling for age, ordinal regression showed that surgical technique at C3 did not increase the odds of postoperative loss of cervical lordosis. C3 laminectomy versus C3 laminoplasty did not differ in the postoperative range of motion on cervical flexion–extension X-rays (23.9° vs. 21.7°, p = 0.451, N = 91). Conclusion: There was no difference in postoperative loss of cervical lordosis or postoperative range of motion in patients who underwent either C3–C6/C7 plated laminoplasty or C3 laminectomy plus C4–C6/C7 plated laminoplasty. Full article

Background: The combined anterior–posterior approach has shown good clinical outcomes for multilevel cervical diseases. This work describes the biomechanical advantage of cervical-pedicle-screw fixation over lateral-mass-screw fixation in combined anterior–posterior cases. Method: Seventy-six patients who received combined cervical surgery from June 2013 to December 2020 were included. The patients were divided into two groups: the lateral-mass-screw group (LMS) and the pedicle-screw group (PPS). Radiological outcomes were assessed with lateral cervical spine X-rays for evaluating sagittal alignment, subsidence, and bone remodeling. Results: At 1 year postoperatively, the numbers of patients whose C2–C7 cervical lordosis was less than 20 degrees decreased by more in the PPS group (p-value = 0.001). The amount of vertical-length change from immediately to 1 year postsurgery was less in the PPS group than in the LMS group (p-value = 0.030). The mean vertebral-body-width change was larger in the PPS group than in the LMS group during 3 months to 1 year postsurgery (p-value = 0.000). Conclusions: In combined anterior–posterior cervical surgery cases, maintenance of cervical lordosis and protection of the vertebral body from subsidence were better with the pedicle-screw fixation. More bone remodeling occurred when using the pedicle-screw fixation method. Full article

C5 palsy is a frequent sequela of cervical decompression surgeries for cervical myeloradiculopathy. Although many researchers have suggested various risk factors, such as cord shifting and the correction of lordotic angles, the tethering of the C5 root beneath the narrow foramen is an independent risk factor for C5 palsy. In this study, we tried to investigate different techniques for foramen decompression with posterior cervical fusion and assess the incidence of C5 palsy with each technique depending on the order of foraminal decompression. A combined 540° approach with LMS and uncovertebrectomy was used in group 1. Group 2 combined a 540° approach with pedicle screws and posterior foraminotomy, while posterior approach only with pedicle screws and foraminotomy was used in group 3. For groups 2 and 3, prophylactic posterior foraminotomy was performed before laminectomy. Motor manual testing to assess C5 palsy, the Neck Disability Index (NDI) and the Japanese Orthopedic Association (JOA) scores were determined before and after surgery. Simple radiographs, MRI and CT scans, were obtained to assess radiologic parameters preoperatively and postoperatively. A total of 362 patients were enrolled in this study: 208 in group 1, 72 in group 2, and 82 in group 3. The mean age was 63.2, 65.5, and 66.6 years in groups 1, 2, and 3, respectively. The median for fused levels was 4 for the three groups. There was no significant difference between groups regarding the number of fused levels. Weight, height, comorbidities, and diagnosis were not significantly different between groups. Preoperative JOA scores were similar between groups (p = 0.256), whereas the preoperative NDI score was significantly higher in group 3 than in group 2 (p = 0.040). Mean JOA score at 12-month follow-up was 15.5 ± 1.89, 16.1 ± 1.48, and 16.1 ± 1.48 for groups 1, 2, and 3, respectively; it was higher in group 3 compared with group 1 (p = 0.008) and in group 2 compared with group 1 (p = 0.024). NDI score at 12 months was 13, 12, and 13 in groups 1, 2, and 3, respectively; it was significantly better in group 3 than in group 1 (p = 0.040), but there were no other significant differences between groups. The incidence of C5 palsy was significantly lower in posterior foraminotomy groups with pedicle screws (groups 2 and 3) than in LMS with uncovertebrectomy (group 1) (p < 0.001). Thus, preventive expansive foraminotomy before decompressive laminectomy is able to significantly decrease the root tethering by stenotic lesion, and subsequently, decrease the incidence of C5 palsy associated with posterior only or combined posterior and anterior cervical fusion surgeries. Additionally, such expansive foraminotomy might be appropriate with pedicle screw insertion based on biomechanical considerations. Full article

The influence of the sequence of surgery in the development of prevertebral soft tissue swelling (PSTS) in staged combined multilevel anterior–posterior complex spine surgery was examined. This study was conducted as a retrospective study of patients who underwent staged combined multilevel anterior–posterior complex cervical spine surgery from March 2014 to February 2021. Eighty-two patients were identified, of which fifty-seven were included in the final analysis after screening. PSTS was measured from routine serial monitoring lateral cervical radiographs prior to and after surgery for five consecutive days at each cervical level from C2 to C7 in patients who underwent anterior then posterior (AP) and posterior then anterior–posterior (PAP) surgery. The mean PSTS measurements significantly differed from the preoperative to postoperative monitoring days at all cervical levels (p = 0.0000) using repeated measures analysis of variance in both groups. PSTS was significantly greater in PAP than in AP at level C2 on postoperative day (POD) 1 (p = 0.0001). PSTS was more prominent at levels C2–4 during PODs 2–4 for both groups. In staged combined multilevel anterior–posterior complex spine surgery, PSTS is an inevitable complication. Therefore, surgeons should monitor PSTS after surgery when performing anterior–posterior complex cervical spine surgery, especially in the immediate postoperative period after PAP surgery. Full article

Intraoperative neuromonitoring (IONM) has become an indispensable surgical adjunct in cervical spine procedures to minimize surgical complications. Understanding the historical development of IONM, indications for use, associated pitfalls, and recent developments will allow the surgeon to better utilize this important technology. While IONM has shown great promise in procedures for cervical deformity, intradural tumors, or myelopathy, routine use in all cervical spine cases with moderate pathology remains controversial. Pitfalls that need to be addressed include human error, a lack of efficient communication, variable alarm warning criteria, and a non-standardized checklist protocol. As the techniques associated with IONM technology become more robust moving forward, IONM emerges as a crucial solution to updating patient safety protocols. Full article