A Comparison of the Anterior Approach and the Posterior Approach in Treating Multilevel Cervical Myelopathy: A Meta-Analysis

Impact of Preoperative Frailty on Outcomes in Patients with Cervical Spondylotic Myelopathy Undergoing Anterior vs. Posterior Cervical Surgery

Introduction: Frailty has been shown to negatively influence patient outcomes across many disease processes, including in the cervical spondylotic myelopathy (CSM) population. The aim of this study was to assess the impact that frailty has on patients with CSM who undergo anterior cervical discectomy and fusion (ACDF) or posterior cervical decompression and fusion (PCDF). Materials and Methods: A retrospective cohort study was performed using the 2016-2019 national inpatient sample. Adult patients (≥18 years old) undergoing ACDF only or PCDF only for CSM were identified using ICD codes. The patients were categorized based on receipt of ACDF or PCDF and pre-operative frailty status using the 11-item modified frailty index (mFI-11): pre-Frail (mFI = 1), frail (mFI = 2), or severely frail (mFI ≥ 3). Patient demographics, comorbidities, operative characteristics, perioperative adverse events (AEs), and healthcare resource utilization were assessed. Multivariate logistic regression analyses were used to identify independent predictors of extended length of stay (LOS) and non-routine discharge (NRD). Results: A total of 37,990 patients were identified, of which 16,665 (43.9%) were in the pre-frail cohort, 12,985 (34.2%) were in the frail cohort, and 8340 (22.0%) were in the severely frail cohort. The prevalence of many comorbidities varied significantly between frailty cohorts. Across all three frailty cohorts, the incidence of AEs was greater in patients who underwent PCDF, with dysphagia being significantly more common in patients who underwent ACDF. Additionally, the rate of adverse events significantly increased between ACDF and PCDF with respect to increasing frailty (p < 0.001). Regarding healthcare resource utilization, LOS and rate of NRD were significantly greater in patients who underwent PCDF in all three frailty cohorts, with these metrics increasing with frailty in both ACDF and PCDF cohorts (LOS: p < 0.001); NRD: p < 0.001). On a multivariate analysis of patients who underwent ACDF, frailty and severe frailty were found to be independent predictors of extended LOS [(frail) OR: 1.39, p < 0.001; (severely frail) OR: 2.25, p < 0.001] and NRD [(frail) OR: 1.49, p < 0.001; (severely frail) OR: 2.22, p < 0.001]. Similarly, in patients who underwent PCDF, frailty and severe frailty were found to be independent predictors of extended LOS [(frail) OR: 1.58, p < 0.001; (severely frail) OR: 2.45, p < 0.001] and NRD [(frail) OR: 1.55, p < 0.001; (severely frail) OR: 1.63, p < 0.001]. Conclusions: Our study suggests that preoperative frailty may impact outcomes after surgical treatment for CSM, with more frail patients having greater health care utilization and a higher rate of adverse events. The patients undergoing PCDF ensued increased health care utilization, compared to ACDF, whereas severely frail patients undergoing PCDF tended to have the longest length of stay and highest rate of non-routine discharge. Additional prospective studies are necessary to directly compare ACDF and PCDF in frail patients with CSM.

Effectiveness of different surgical methods in the treatment of acute central cord syndrome without fractures and dislocations of the cervical spine

BACKGROUND

Acute central cord syndrome (ACCS) without fractures or dislocations is the most common form of incomplete spinal cord injury.

OBJECTIVE

To evaluate the effectiveness of different surgical methods in the treatment of acute central cord syndrome without fractures or dislocations of the cervical spine.

METHODS

A total of 164 patients with ACCS without fracture or dislocation of the cervical spine treated in our hospital from May 2012 to October 2019 were recruited and assigned to study group A and study group B according to different treatment modalities, with 82 cases in each group. Study group A underwent anterior cervical discectomy and fusion, and study group B was treated with posterior cervical laminectomy. The American Spinal Injury Association (ASIA) classification and motor scores of all cases at admission and at discharge were recorded, and the treatment outcomes of the two groups were compared.

RESULTS

No significant differences were found in the ASIA classification and ASIA motor scores between the two groups at admission (P> 0.05). One year after surgery, the ASIA motor scores and sensory scores were not statistically significant between the two groups (P> 0.05) but showed significant improvement compared to the preoperative scores (P< 0.05).

CONCLUSION

Both anterior cervical discectomy and fusion and posterior cervical laminectomy can improve the ASIA classification, ASIA motor scores, and sensory scores of ACCS patients without fractures or dislocations of the cervical spine. Therefore, surgical methods should be adopted based on the patients' conditions.

Comparison of anterior cervical discectomy and fusion versus artificial disc replacement for cervical spondylotic myelopathy: a meta-analysis

OBJECTIVE

Anterior cervical discectomy and fusion (ACDF) has long been regarded as a gold standard in the treatment of cervical myelopathy. Subsequently, cervical artificial disc replacement (c-ADR) was developed and provides the advantage of motion preservation at the level of the intervertebral disc surgical site, which may also reduce stress at adjacent levels. The goal of this study was to compare clinical and functional outcomes in patients undergoing ACDF with those in patients undergoing c-ADR for cervical spondylotic myelopathy (CSM).

METHODS

A systematic literature review and meta-analysis were performed using the Embase, PubMed, and Cochrane Central Register of Controlled Trials databases from database inception to November 21, 2021. The authors compared Neck Disability Index (NDI), SF-36, and Japanese Orthopaedic Association (JOA) scores; complication rates; and reoperation rates for these two surgical procedures in CSM patients. The Mantel-Haenszel method and variance-weighted means were used to analyze outcomes after identifying articles that met study inclusion criteria.

RESULTS

More surgical time was consumed in the c-ADR surgery (p = 0.04). Shorter hospital stays were noted in patients who had undergone c-ADR (p = 0.04). Patients who had undergone c-ADR tended to have better NDI scores (p = 0.02) and SF-36 scores (p = 0.001). Comparable outcomes in terms of JOA scores (p = 0.24) and neurological success rate (p = 0.12) were noted after the surgery. There was no significant between-group difference in the overall complication rates (c-ADR: 18% vs ACDF: 25%, p = 0.17). However, patients in the ACDF group had a higher reoperation rate than patients in the c-ADR group (4.6% vs 1.5%, p = 0.02).

CONCLUSIONS

At the midterm follow-up after treatment of CSM, better functional outcomes as reflected by NDI and SF-36 scores were noted in the c-ADR group than those in the ACDF group. c-ADR had the advantage of retaining range of motion at the level of the intervertebral disc surgical site without causing more complications. A large sample size with long-term follow-up studies may be required to confirm these findings in the future.

A systematic review and meta-analysis comparing anterior decompression with fusion and posterior laminoplasty for cervical spondylotic myelopathy

BACKGROUND

The optimal surgical procedure for the treatment of cervical spondylotic myelopathy (CSM) remains controversial because there are few comprehensive studies that have investigated the surgical methods. Therefore, we conducted a systematic review and meta-analysis to evaluate evidence in the literature and to compare the surgical outcomes between anterior decompression with fusion (ADF) and laminoplasty, which are representative procedures for CSM.

METHODS

An extensive literature search was performed using PubMed, Embase, and the Cochrane Library to identify comparative studies of ADF and laminoplasty for CSM. The language was restricted to English, and the publication period was from January 2001 to July 2019. We only included studies of CSM and excluded studies that involved patients with ossification of the posterior longitudinal ligament and treatments with posterior instrumented fusion. We extracted outcomes from the studies, such as preoperative and postoperative Japanese Orthopaedic Association (JOA) scores, cervical alignment, surgical complications and reoperation rates. Then, a meta-analysis was performed on these surgical outcomes.

RESULTS

Nine studies were obtained, and the quality of the studies was acceptable. In the meta-analysis, the preoperative JOA score was similar between the ADF and laminoplasty groups. The postoperative JOA scores and neurological recovery rates were not different between the ADF and laminoplasty groups. ADF exhibited more favorable results than laminoplasty in terms of postoperative cervical alignment. In contrast, overall complications were more frequently observed in the ADF group than in the laminoplasty group, leading to higher rates of reoperation. However, postoperative neck pain was more frequently observed in the laminoplasty group than in the ADF group.

CONCLUSIONS

This systematic review and meta-analysis showed both the merits and shortcomings of ADF and laminoplasty. ADF and laminoplasty showed similar results in terms of neurological recovery. Postoperative cervical lordosis was better preserved with ADF than with laminoplasty. However, ADF was associated with a higher incidence of surgical complications than laminoplasty.

Comparison of anterior decompression with fusion and posterior decompression with fusion for cervical spondylotic myelopathy-A systematic review and meta-analysis

BACKGROUND

The optimal surgical procedure for the treatment of cervical spondylotic myelopathy (CSM) remains controversial. Recently, laminectomy/laminoplasty with instrumented fusion (LAMF) has been increasingly applied to treat CSM. However, few comprehensive studies have compared anterior decompression with fusion (ADF) and LAMF. Therefore, we conducted a meta-analysis to evaluate the evidence in the literature and to compare the surgical outcomes between the 2 procedures. Since the surgical outcomes and risks differ between patients with CSM and ossification of the posterior longitudinal ligament (OPLL) and between only posterior decompression and decompression with fusion treatments, we excluded patients with OPLL and patients with only posterior decompression in this review.

METHODS

An extensive literature search was performed using PubMed, Embase, and the Cochrane Library to identify comparative studies of ADF and LAMF for the treatment of CSM. The language was restricted to English, and the publication period was from January 2001 to July 2019. We only included studies about CSM and excluded studies that involved patients with ossification of the posterior longitudinal ligament and with the treatment of posterior decompression without fusion. We extracted outcomes from the studies, such as preoperative and postoperative Japanese Orthopaedic Association (JOA) scores, neck disability index (NDI) scores, cervical alignment data, and surgical complications. Then, a meta-analysis was performed on these surgical outcomes.

RESULTS

Eleven studies were obtained, and the quality of the studies was acceptable. In the meta-analysis, the pre- and postoperative JOA scores were similar between the ADF and LAMF groups. The ADF group exhibited more favorable results than the LAMF group in terms of postoperative cervical alignment and the NDI. Overall complications were similar between the ADF and LAMF groups; however, C5 palsy was more frequently observed in the LAMF group than in the ADF group.

CONCLUSIONS

While the ADF and LAMF groups demonstrated similar results in terms of neurological recovery, postoperative cervical lordosis and NDI scores were more favorable with ADF than with LAMF. The overall complication rate was similar between the ADF and LAMF groups. Surgeons should understand the merits and shortcomings of both procedures when deciding on a surgical procedure.

Surgical approaches and outcomes for cervical myelopathy with increased signal intensity on T2-weighted MRI: a meta-analysis

OBJECTIVE

Increased signal intensity (ISI) on T2-weighted magnetic resonance imaging (MRI) often indicates severe compression in patients with cervical myelopathy (CM). The optimal surgical approach for CM patients with ISI on T2-weighted MRI remains unclear. This meta-analysis aims to compare the clinical outcomes between anterior and posterior approaches for the treatment of these patients.

METHODS

MEDLINE, EMBASE, Web of Science, and Chinese National Knowledge Infrastructure (CNKI) were searched for relevant studies through January 2019. Statistical comparisons were made when appropriate.

RESULTS

A total of 9 studies (748 participants) out of 1066 citations were included in this study. All of the selected studies were high quality, as indicated by the Newcastle-Ottawa scale and the Cochrane Collaboration tool for assessing the risk of bias. Clinical outcomes were compared between anterior and posterior approaches in 4 studies (237 participants). The preoperative Japanese Orthopedic Association (JOA) score was similar between the two groups [P = 0.98, weighted mean difference (WMD) = 0.01 (- 0.58, 0.59)]. The postoperative JOA score [P < 0.05, WMD = 0.68 (0.06, 1.30)] and recovery rates [P < 0.01, WMD = 0.12 (0.06, 0.17)] were significantly higher in the anterior group than in the posterior group.

CONCLUSION

The anterior approach was associated with better postoperative neural function than the posterior approach in CM patients with ISI on T2-weighted MRI.

Development and Achievement of Cervical Laminoplasty and Related Studies on Cervical Myelopathy

Cervical laminoplasty (CL) is one of the surgical methods via the posterior approach for treating patients with multilevel affected cervical myelopathy (CM). The main purpose of CL is to decompress the cervical spinal cord by widening the narrowed spinal canal, combined with preserving the posterior anatomical structures to the degree possible and preserving the widened space stably. During the development and improvement of spine surgeries including CL, various studies on CM have progressed and useful achievements have been obtained: (1) posterior cervical spine fixation systems that can be used in combination with CL simultaneously have been developed; (2) various materials to stably maintain the enlarged spinal canal have been developed; (3) the main influential factors on the surgical results are the inner factors of the patients, such as the patient's age and the disease duration; (4) various surgical methods to preserve the function of the posterior cervical muscles have been tried to avoid postoperative kyphotic changes of the cervical spine; (5) postoperative complications, such as C5 palsy and axial pain, have been examined, and the countermeasures have been tried; (6) K-line on lateral X-ray films has been applied to evaluate the indication of CL in patients with CM due to ossification of the posterior longitudinal ligament (OPLL) preoperatively; and (7) the method and idea of CL have been adapted to surgeries at the thoracic and lumbar spine. However, some issues remain to be resolved, such as the deterioration of neurological findings, especially in patients with continuous or mixed-type OPLL, the postoperative kyphotic-directional alignment change of the cervical spine, C5 palsy, and axial pain.

Anterior versus posterior approach for the therapy of multilevel cervical spondylotic myelopathy: a meta-analysis and systematic review

BACKGROUND

The goal of this meta-analysis is to explore the overall efficacy as well as the safety of anterior versus posterior approach for the therapy of patients with multilevel cervical spondylotic myelopathy based on qualified studies.

METHODS

Three electronic databases, PubMed, Cochrane, Embase were searched updated to January 2018 to identify all relevant and qualified studies using the index words. The qualified studies were including prospective or retrospective comparative studies. Relative risk (RR) and mean difference (MD) along with 95% confidence interval (95% CI) were used to analyze the main outcomes.

RESULTS

In this meta-analysis, there were a total of 24 studies with 959 patients in the anterior approach group and 1072 patients in the posterior approach group. The final results showed, in comparison of the posterior approach group, the anterior approach group significantly increased the JOA score (SMD: 0.36, 95% CI 0.10-0.62), the operation time (WMD: 49.87, 95% CI 17.67-82.08), and the neurological recovery rate (WMD: 10.55, 95% CI 3.99-17.11) with higher complication rate (RR: 1.53, 95% CI 1.24-1.89). Besides, there was no significant difference of the blood loss (SMD: - 0.40, 95% CI - 1.12 to 0.32) and ROM (SMD: - 0.28, 95% CI - 0.78 to - 0.22) between posterior approach group and anterior approach group.

CONCLUSIONS

Studies found a significant increase of JOA score as well as neurological recovery rate by the anterior approach treatment when compared with posterior approach treatment. However, increased operation time and complications could also occur through the anterior approach treatment. More high-quality randomized controlled trials with larger sample size, multi-centric and longer follow-ups are needed to support our current conclusions.