Treatment of multilevel cervical spondylotic myeloradiculopathy with posterior decompression and fusion with lateral mass plate fixation and local bone graft

Design and Validation of a Novel Robotic Neck Brace for Cervical Traction

Cervical traction is a common and effective treatment for degenerative disk diseases and pain in the cervical spine. However, the manual or mechanical methods of applying traction to the head-neck are limited due to variability in the applied forces and orientation of the head-neck relative to the shoulder during the procedure. Current robotic neck braces are not designed to provide independent rotation angles and independent vertical translation, or traction, to the brace end-effector connected to the head, making them unsuitable for traction application. This work proposes a novel architecture of a robotic neck brace, which can provide vertical traction to the head while keeping the head in a prescribed orientation, with flexion and lateral bending angles. In this paper, the kinematics of the end-effector attached to the head relative to a coordinate frame on the shoulders are described as well as the velocity kinematics and force control. The paper also describes benchtop experiments designed to validate the position control and the ability of the brace to provide a vertical traction force. It was shown that the maximum achievable end-effector orientations are 16° in flexion, 13.9° in extension, and ± 6.5° in lateral bending. The kinematic model of the active brace was validated using an independent motion capture system with a maximum root mean square error of 2.41°. In three different orientations of the end-effector, neutral, flexed, and laterally bent, the brace was able to provide a consistent upward traction force during intermittent force application. In these configurations, the force error has standard deviations of 0.55, 0.29, and 0.07N, respectively. This work validates the mechanism's ability to achieve a range of head orientations and provide consistent upward traction force in these orientations, making it a promising intervention tool in cases of cervical disk degeneration.

Are There Advantages in Cervical Intrafacetal Fusion With Minimal Posterolateral Fusion (PLF) Compared to Conventional PLF in Posterior Cervical Fusion?

OBJECTIVE

We propose that cervical intrafacetal fusion (cIFF) using bone chip insertion into the facetal joint space additional to minimal PLF is a supplementary fusion method to conventional posterolateral fusion (PLF).

METHODS

Patients who underwent posterior cervical fixation accompanied by cIFF with minimal PLF or conventional PLF for cervical myelopathy from 2012 to 2023 were investigated retrospectively. Radiological parameters including Cobb angle and C2-7 sagittal vertical axis (SVA) were compared between the 2 groups. In cIFF with minimal PLF group, cIFF location and PLF location were carefully divided, and the fusion rates of each location were analyzed by computed tomography scan.

RESULTS

Among enrolled 46 patients, 31 patients were in cIFF group, 15 in PLF group. The postoperative change of Cobb angle in 1-year follow-up in cIFF with minimal PLF group and conventional PLF group were 0.1° ± 4.0° and -9.7° ± 8.4° respectively which was statistically lower in cIFF with minimal PLF group (p = 0.022). Regarding the fusion rate in cIFF with minimal PLF group in postoperative 6 months, the rates was achieved in 267 facets (98.1%) in cIFF location, and 244 facets (89.7%) in PLF location (p < 0.001).

CONCLUSION

Postoperative sagittal alignment was more preserved in cIFF with minimal PLF group compared with conventional PLF group. Additionally, in cIFF with minimal PLF group, the bone fusion rate of cIFF location was higher than PLF location. Considering the concerns of bone chip migration onto the spinal cord and relatively low fusion rate in PLF method, applying cIFF method using minimized PLF might be a beneficial alternative for posterior cervical decompression and fixation.

Comparison of radiological and clinical outcomes of cervical laminoplasty versus lateral mass screw fixation in patients with ossification of the posterior longitudinal ligament

PURPOSE

This study aimed to compare cervical sagittal parameters and clinical outcomes between patients undergoing cervical laminoplasty(CL) and those undergoing lateral mass screw fixation(LMS).

METHODS

We retrospectively studied 67 patients with multilevel ossification of the posterior longitudinal ligament (OPLL) of the cervical spine who underwent lateral mass screw fixation (LMS = 36) and cervical laminoplasty (CL = 31). We analyzed cervical sagittal parameters (C2-7 sagittal vertical axis (C2-7 SVA), C0-2 Cobb angle, C2-7 Cobb angle, C7 slope (C7s), T1 slope (T1s), and spino-cranial angle (SCA)) and clinical outcomes (visual analog scale [VAS], neck disability index [NDI], Japanese Orthopaedic Association [JOA] scores, recovery rate (RR), and minimum clinically significant difference [MCID]). The cervical sagittal parameters at the last follow-up were analyzed by binary logistic regression. Finally, we analyzed the correlation between the cervical sagittal parameters and each clinical outcome at the last follow-up after surgery in both groups.

RESULTS

At the follow-up after posterior decompression in both groups, the mean values of C2-C7 SVA, C7s, and T1s in the LMS group were more significant than those in the CL group (P ≤ 0.05). Compared with the preoperative period, C2-C7 SVA, T1s, and SCA gradually increased, and the C2-C7 Cobb angle gradually decreased after surgery (P < 0.05). The improvement in the JOA score and the recovery rate was similar between the two groups, while the improvement in the VAS-N score and NDI score was more significant in the CL group (P = 0.001; P = 0.043). More patients reached MCID in the CL group than in the LMS group (P = 0.036). Binary logistic regression analysis showed that SCA was independently associated with whether patients reached MCID at NDI postoperatively. SCA was positively correlated with cervical NDI and negatively correlated with cervical JOA score at postoperative follow-up in both groups (P < 0.05); C2-7 Cobb angle was negatively correlated with cervical JOA score at postoperative follow-up (P < 0.05).

CONCLUSION

CL may be superior to LMS in treating cervical spondylotic myelopathy caused by OPLL. In addition, smaller cervical SCA after posterior decompression may suggest better postoperative outcomes.

Is Severe Neck Pain a Contraindication to Performing Laminoplasty in Patients With Cervical Spondylotic Myelopathy?

STUDY DESIGN

Retrospective review.

OBJECTIVE

The purpose of this study was to investigate the surgical outcomes in a cohort of patients with severe preoperative axial neck pain undergoing laminoplasty for cervical spondylotic myelopathy (CSM).

SUMMARY OF BACKGROUND DATA

No study has investigated whether patients with severe axial symptoms may achieve satisfactory neck pain and disability outcomes after laminoplasty.

METHODS

We performed a retrospective review of 91 patients undergoing C4-6 laminoplasty for CSM at a single academic institution between 2010 and 2021. Patient-reported outcome measures (PROMs), including Neck Disability Index (NDI), visual analog scale (VAS) Neck, and VAS Arm, were recorded preoperatively and at 6 months and 1 year postoperatively. Patients were stratified as having mild pain if VAS neck was 0-3, moderate pain if 4-6, and severe pain if 7-10. PROMs were then compared between subgroups at all the perioperative time points.

RESULTS

Both the moderate and severe neck pain subgroups demonstrated a substantial improvement in VAS neck from preoperative to 6 months postoperatively (-3.1±2.2 vs. -5.6±2.8, respectively; P <0.001), and these improvements were maintained at 1 year postoperatively. There was no difference in VAS neck between subgroups at either the 6-month or 1-year postoperative time points. Despite the substantially higher mean NDI in the moderate and severe neck pain subgroups preoperatively, there was no difference in NDI at 6 months or 1 year postoperatively ( P =0.99). There were no differences between subgroups in the degree of cord compression, severity of multifidus sarcopenia, sagittal alignment, or complications.

CONCLUSIONS

Patients with moderate and severe preoperative neck pain undergoing laminoplasty achieved equivalent PROMs at 6 months and 1 year as patients with mild preoperative neck pain. The results of this study highlight the multifactorial nature of neck pain in these patients and indicate that severe axial symptoms are not an absolute contraindication to performing laminoplasty in well-aligned patients with CSM.

The Effect of Laminectomy with Instrumented Fusion Carried into the Thoracic Spine on the Sagittal Imbalance in Patients with Multilevel Ossification of the Posterior Longitudinal Ligament

OBJECTIVE

To determine if there is a difference in either the cervical alignment or the clinical outcomes in cervical ossification of the posterior longitudinal ligament (OPLL) patients who underwent laminectomy with instrumented fusion (LIF) ending at C₆ , C₇ , or proximal thoracic spine for the treatment of multilevel OPLL, and to find out the appropriate distal fusion level.

METHODS

This was a single-center retrospective study. In total, 36 patients with cervical OPLL who underwent three or more level LIF in our institution between January 2015 and January 2017 were enrolled. They were divided into three groups according to their distal ends: C₆ (nine females and 11 males, 60.45 ± 9.68 years old), C₇ (four females and six males, 61.60 ± 10.29 years old), and T-group (two females and four males, 64.33 ± 8.12 years old). Radiographic (compression level, classification of OPLL, occupying rate, C_2-7 cobb angle, C_2-7 sagittal vertical axis, and fusion level) and clinical outcomes (NDI score, operative time, and blood loss) were compared. Predictors of postoperative sagittal imbalance were also identified according to if the postoperative C_2-7 SVA was greater than 40 mm. The sensitivity and specificity of preoperative parameters predicting postoperative cervical stability were evaluated via the receiver operating characteristic (ROC) curve.

RESULTS

All patients were followed up at least 1 year. The blood loss in T group was significantly more than C₆ or C₇ group. The length of fusion level became significantly longer when the caudal level extended to the thoracic spine. The age, preoperative SVA, and NDI score at follow-up were significantly greater in the imbalance group. At the final follow-up, the cervical lordosis tended to be straight and the C_2-7 SVA tended to be greater when the caudal level of fusion was extended to upper thoracic segment. Further ROC curve analysis suggested that patients' age had a sensitivity of 75.00%, specificity of 79.17% for cervical stability, and the AUC was 0.844 (P < 0.01), with the cutoff value for age being 66.5 years old. For preoperative SVA, the sensitivity was 58.30%, and specificity was 91.70%, with the AUC of 0.778 (P < 0.01). The cutoff value for preoperative SVA was 30.4 mm.

CONCLUSION

Although posterior fusion terminating in the thoracic spine was not superior to the cervical spine for patients with multilevel OPLL, for elderly patients (>67 years) with great preoperative SVA (>30 mm), terminating at C₆ was recommended to limit the invasion of cervical extensor muscles, provided the decompression was adequate.

Relationship of Change in Cervical Curvature after Laminectomy with Lateral Mass Screw Fixation to Spinal Cord Shift and Clinical Efficacy

BACKGROUND AND STUDY AIMS

 Although laminectomy with lateral mass screw fixation (LCSF) is an effective surgical treatment for cervical spondylotic myelopathy (CSM), loss of cervical curvature may result. This study aimed to investigate the effect of cervical curvature on spinal cord drift distance and clinical efficacy.

PATIENTS AND METHODS

 We retrospectively analyzed 78 consecutive CSM patients with normal cervical curvature who underwent LCSF. Cervical curvature was measured according to Borden's method 6 months after surgery. Study patients were divided into two groups: group A, reduced cervical curvature (cervical lordosis depth 0-7mm; n = 42); and group B, normal cervical curvature (cervical lordosis depth 7-17mm; n = 36). Spinal cord drift distance, laminectomy width, neurologic functional recovery, axial symptom (AS) severity, and incidence of C5 palsy were measured and compared.

RESULTS

 Cervical lordosis depth was 5.1 ± 1.2 mm in group A and 12.3 ± 2.4 mm in group B (p < 0.05). Laminectomy width was 21.5 ± 2.6 mm in group A and 21.9 ± 2.8 mm in group B (p > 0.05). Spinal cord drift distance was significantly shorter in group A (1.9 ± 0.4 vs. 2.6 ± 0.7 mm; p < 0.05). The Japanese Orthopaedic Association (JOA) score significantly increased after surgery in both groups (p < 0.05). Neurologic recovery rate did not differ between the two groups (61.5 vs. 62.7%; p > 0.05). AS severity was significantly higher in group A (p < 0.05). C5 palsy occurred in three group A patients (7.1%) and four group B patients (11.1%), but the difference was not significant (p > 0.05).

CONCLUSION

 After LCSF, 53.8% of the patients developed loss of cervical curvature. A smaller cervical curvature resulted in a shorter spinal cord drift distance. Loss of cervical curvature was related to AS severity but not improvement of neurologic function or incidence of C5 palsy.

A biomechanical analysis of four anterior cervical techniques to treating multilevel cervical spondylotic myelopathy: a finite element study

BACKGROUND

The decision to treat multilevel cervical spondylotic myelopathy (MCSM) remains controversial. The purpose of this study is to compare the biomechanical characteristics of the intervertebral discs at the adjacent segments and internal fixation, and to provide scientific experimental evidence for surgical treatment of MCSM.

METHODS

An intact C2-C7 cervical spine model was developed and validated. Four additional models were developed from the fusion model, including multilevel anterior cervical discectomy and fusion (mACDF), anterior cervical corpectomy and fusion (ACCF), hybrid decompression and fusion (HDF), and mACDF with cage alone (mACDF-CA). Biomechanical characteristics on the plate and the disc of adjacent levels (C2/3, C6/7) were comparatively analyzed.

RESULTS

Of the four models, stress on the upper (C2/3) adjacent intervertebral disc was the lowest in the mACDF-CA group and highest in the ACCF group. Stress on the intervertebral discs at adjacent segments was higher for the upper C2/3 than the lower C6/7 intervertebral disc. In all models, the mACDF-CA group had the lowest stress on the intervertebral disc, while the ACCF group had the highest stress. In the three surgical models with titanium plate fixation (mACDF, ACCF, and HDF), the ACCF group had the highest stress at the titanium plate-screw interface, while the mACDF group had the lowest stress.

CONCLUSION

Among the four anterior cervical reconstructive techniques for MCSM, mACDF-CA makes little effect on the adjacent disc stress, which might reduce the incidence of adjacent segment degeneration (ASD) after fusion. However, the accompanying risk of the increased incidence of cage subsidence should never be neglected.

Effect of Ventral vs Dorsal Spinal Surgery on Patient-Reported Physical Functioning in Patients With Cervical Spondylotic Myelopathy: A Randomized Clinical Trial

Importance

Cervical spondylotic myelopathy is the most common cause of spinal cord dysfunction worldwide. It remains unknown whether a ventral or dorsal surgical approach provides the best results.

Objective

To determine whether a ventral surgical approach compared with a dorsal surgical approach for treatment of cervical spondylotic myelopathy improves patient-reported physical functioning at 1 year.

Design, Setting, and Participants

Randomized clinical trial of patients aged 45 to 80 years with multilevel cervical spondylotic myelopathy enrolled at 15 large North American hospitals from April 1, 2014, to March 30, 2018; final follow-up was April 15, 2020.

Interventions

Patients were randomized to undergo ventral surgery (n = 63) or dorsal surgery (n = 100). Ventral surgery involved anterior cervical disk removal and instrumented fusion. Dorsal surgery involved laminectomy with instrumented fusion or open-door laminoplasty. Type of dorsal surgery (fusion or laminoplasty) was at surgeon's discretion.

Main Outcomes and Measures

The primary outcome was 1-year change in the Short Form 36 physical component summary (SF-36 PCS) score (range, 0 [worst] to 100 [best]; minimum clinically important difference = 5). Secondary outcomes included 1-year change in modified Japanese Orthopaedic Association scale score, complications, work status, sagittal vertical axis, health resource utilization, and 1- and 2-year changes in the Neck Disability Index and the EuroQol 5 Dimensions score.

Results

Among 163 patients who were randomized (mean age, 62 years; 80 [49%] women), 155 (95%) completed the trial at 1 year (80% at 2 years). All patients had surgery, but 5 patients did not receive their allocated surgery (ventral: n = 1; dorsal: n = 4). One-year SF-36 PCS mean improvement was not significantly different between ventral surgery (5.9 points) and dorsal surgery (6.2 points) (estimated mean difference, 0.3; 95% CI, -2.6 to 3.1; P = .86). Of 7 prespecified secondary outcomes, 6 showed no significant difference. Rates of complications in the ventral and dorsal surgery groups, respectively, were 48% vs 24% (difference, 24%; 95% CI, 8.7%-38.5%; P = .002) and included dysphagia (41% vs 0%), new neurological deficit (2% vs 9%), reoperations (6% vs 4%), and readmissions within 30 days (0% vs 7%).

Conclusions and Relevance

Among patients with cervical spondylotic myelopathy undergoing cervical spinal surgery, a ventral surgical approach did not significantly improve patient-reported physical functioning at 1 year compared with outcomes after a dorsal surgical approach.

Trial Registration

ClinicalTrials.gov Identifier: NCT02076113.

Comparison of 30-Day Outcomes in Patients with Cervical Spine Metastasis Undergoing Corpectomy Versus Posterior Cervical Laminectomy and Fusion: A 2006-2016 ACS-NSQIP Database Study

BACKGROUND

Patients with metastatic disease to the cervical spine have historically had poor outcomes, with an average survival of 15 months. Every effort should be made to avoid complications of surgical intervention for stabilization and decompression.

METHODS

We identified patients who had undergone anterior cervical corpectomy and fusion (ACCF) or posterior cervical laminectomy and fusion (PCLF) for metastatic disease of the cervical spine using the American College of Surgeons National Surgical Quality Improvement Program database from 2006 to 2016. Patients meeting the inclusion criteria were subsequently propensity matched 1:1. We compared the overall complications, intensive care unit level complications, mortality, and return to the operating room between the 2 groups.

RESULTS

After identifying the patients who met the inclusion criteria and propensity matching, a cohort of 240 patients was included, with 120 (50%) in the ACCF group and 120 (50%) in the PCLF group. The patients in the ACCF group were more likely to have experienced any complication (odds ratio, 2.1; 95% confidence interval, 1.1-4.1; P = 0.026) but not severe complications or a return to the operating room (P = 0.406 and P = 0.450, respectively).

CONCLUSION

In the present study, we found that anterior surgical approaches (ACCF) for metastatic cervical spine disease resulted in a significantly greater rate of overall complications (2.1 times more) compared with PCLF in the first 30 days. Although more studies are required to further elucidate this relationship, the general belief that the anterior approach is better tolerated by patients might not apply to patients with metastatic tumors.

Outcomes of posterior cervical fusion and decompression: a systematic review and meta-analysis

BACKGROUND CONTEXT

Posterior cervical fusion (PCF) with decompression is a treatment option for patients with conditions such as spondylosis, spinal stenosis, and degenerative disc disorders that result in myelopathy or radiculopathy. The annual rate, number, and cost of PCF in the United States has increased. Far fewer studies have been published on PCF outcomes than on anterior cervical fusion (ACF) outcomes, most likely because far fewer PCFs than ACFs are performed.

PURPOSE

To evaluate the patient-reported and clinical outcomes of adult patients who underwent subaxial posterior cervical fusion with decompression.

STUDY DESIGN/SETTING

Systematic review and meta-analysis.

PATIENT SAMPLE

The total number of patients in the 31 articles reviewed and included in the meta-analysis was 1,238 (range 7-166).

OUTCOME MEASURES

Preoperative to postoperative change in patient-reported outcomes (visual analog scales for arm pain and neck pain, Neck Disability Index, Japanese Orthopaedic Association [JOA] score, modified JOA score, and Nurick pain scale) and rates of fusion, revision, and complications or adverse events.

METHODS

This study was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and a preapproved protocol. PubMed and Embase databases were searched for articles published from January 2001 through July 2018. Statistical analyses for patient-reported outcomes were performed on the outcomes' raw mean differences, calculated as postoperative value minus preoperative value from each study. Pooled rates of successful fusion, revision surgery, and complications or adverse events, and their 95% confidence intervals, were also calculated. Two subgroup analyses were performed: one for studies in which only myelopathy or radiculopathy (or both) were stated as surgical indications and the other for studies in which only myelopathy or ossification of the posterior longitudinal ligament (or both) were stated as surgical indications. This study was funded by Providence Medical Technology, Inc. ($32,000).

RESULTS

Thirty-three articles were included in the systematic review, and 31 articles were included in the meta-analysis. For all surgical indications and for the 2 subgroup analyses, every cumulative change in patient-reported outcome improved. Many of the reported changes in patient-reported outcome also exceeded the minimal clinically important differences. Pooled outcome rates with all surgical indications were 98.25% for successful fusion, 1.09% for revision, and 9.02% for complications or adverse events. Commonly reported complications or adverse events were axial pain, C5 palsy, transient neurological worsening, and wound infection.

CONCLUSIONS

Posterior cervical fusion with decompression resulted in significant clinical improvement, as indicated by the changes in patient-reported outcomes. Additionally, high fusion rates and low rates of revision and of complications and adverse events were found.

Cervical Laminectomy With or Without Lateral Mass Instrumentation: A Comparison of Outcomes

STUDY DESIGN

Narrative review.

BACKGROUND

Cervical decompressive laminectomy is a common posterior approach for addressing multilevel cervical spondylotic myelopathy. However, there is a concern that cervical laminectomy can lead to kyphotic deformity with subsequent neurological decline. In this context, cervical laminectomy with fusion using lateral mass instrumentation has become increasingly utilized with the aim of reducing the risk of developing postoperative kyphotic deformity, which is thought to predispose to poorer neurological outcomes in the long term.

OBJECTIVE

To compare the evidence for stand-alone cervical laminectomy with laminectomy with posterior fusion in terms of clinical outcomes and the incidence of adverse events, particularly the development of postoperative cervical kyphosis.

MATERIAL AND METHODS

Initial Medline search using MeSH terms yielded 226 articles, 23 of which were selected. An additional PubMed search and the reference list of individual papers were utilized to identify the remaining papers of relevance.

RESULTS

Cervical laminectomy both with and without fusion offers effective decompression for symptomatic multilevel cervical spondylotic myelopathy. The incidence of postlaminectomy kyphosis is lower following posterior fusion; however, there seems to be no clinical-radiologic correlation given that patients who develop postoperative kyphosis often do not progress to clinical myelopathy. Furthermore, there are specific additional risks of posterior instrumentation that need to be considered.

CONCLUSION

In carefully selected patients with normal preoperative cervical sagittal alignment, stand-alone cervical laminectomy may offer acceptably low rates of postoperative kyphosis. In patients with preoperative loss of cervical lordosis and/or kyphosis, posterior fusion is recommended to reduce the risk of progression to postoperative kyphotic deformity, bearing in mind that radiologic evidence of kyphosis may not necessarily correlate with poorer clinical outcomes. Furthermore, the specific risks associated with posterior fusion (instrumentation failure, pseudarthrosis, infection, C5 nerve root palsy, and vertebral artery injury) need to be considered and weighed up against potential benefits.

The effect of C2-3 disc angle on postoperative adverse events in cervical spondylotic myelopathy

OBJECTIVEComplete radiographic and clinical evaluations are essential in the surgical treatment of cervical spondylotic myelopathy (CSM). Prior studies have correlated cervical sagittal imbalance and kyphosis with disability and worse health-related quality of life. However, little is known about C2-3 disc angle and its correlation with postoperative outcomes. The present study is the first to consider C2-3 disc angle as an additional radiographic predictor of postoperative adverse events.METHODSA retrospective chart review was performed to identify patients with CSM who underwent surgeries from 2010 to 2014. Data collected included demographics, baseline presenting factors, and postoperative outcomes. Cervical sagittal alignment variables were measured using the preoperative and postoperative radiographs. Univariable logistic regression analyses were used to explore the association between dependent and independent variables, and a multivariable logistic regression model was created using stepwise variable selection.RESULTSThe authors identified 171 patients who had complete preoperative and postoperative radiographic and outcomes data. The overall rate of postoperative adverse events was 33% (57/171), and postoperative C2-3 disc angle, C2-7 sagittal vertical axis, and C2-7 Cobb angle were found to be significantly associated with adverse events. Inclusion of postoperative C2-3 disc angle in the analysis led to the best prediction of adverse events. The mean postoperative C2-3 disc angle for patients with any postoperative adverse event was 32.3° ± 17.2°, and the mean for those without any adverse event was 22.4° ± 11.1° (p < 0.0001).CONCLUSIONSIn the present retrospective analysis of postoperative adverse events in patients with CSM, the authors found a significant association between C2-3 disc angle and postoperative adverse events. They propose that C2-3 disc angle be used as an additional parameter of cervical spinal sagittal alignment and predictor for operative outcomes.

Predictive Risk Factors of Nonhome Discharge Following Elective Posterior Cervical Fusion

OBJECTIVE

To identify risk factors that are predictive of nonhome discharge after elective posterior cervical fusion.

METHODS

We performed a retrospective cohort study of adult patients who underwent elective posterior cervical fusion using the American College of Surgeons National Surgical Quality Improvement Program database from 2010 to 2014. Patients were divided into 2 groups: home discharge and nonhome discharge. Univariate analysis was performed to compare incidence of 30-day postoperative complications between groups. Multivariate analysis was performed to identify complications that were predictive of nonhome discharge.

RESULTS

The cohort included 2875 patients; 24.1% were discharged to a nonhome facility, including skilled and nonskilled care facilities, nursing homes, assisted living facilities, and rehabilitation facilities. Nonhome discharge was associated with higher rates of 30-day pulmonary complication, cardiac complication, venous thromboembolism, urinary tract infection, blood transfusion, sepsis, and reoperation. Significant predictors of nonhome discharge were wound complication (odds ratio [OR] = 1.73; 95% confidence interval [CI], 1.07-2.80; P = 0.024), pulmonary complication (OR = 3.61; 95% CI, 1.96-6.63; P < 0.001), cardiac complication (OR = 6.13; 95% CI, 1.61-23.4; P = 0.008), venous thromboembolism (OR = 2.97; 95% CI, 1.43-6.19; P = 0.004), urinary tract infection (OR = 2.69; 95% CI, 1.50-4.82; P < 0.001), blood transfusion (OR = 1.70; 95% CI, 1.20-2.39; P = 0.003), sepsis (OR = 2.75; 95% CI, 1.25-6.02; P = 0.012), and prolonged length of stay (OR = 4.07; 95% CI, 3.34-4.95; P < 0.001).

CONCLUSIONS

Early identification of patients who are at high risk for nonhome discharge is important to implement early comprehensive discharge planning protocols and minimize hospital-acquired conditions related to prolonged length of stay and associated health care costs.

Regression of Anterior Disk-Osteophyte Complex Following Cervical Laminectomy and Fusion for Cervical Spondylotic Myelopathy

STUDY DESIGN

A retrospective case-control study.

OBJECTIVE

To investigate whether posterior cervical laminectomy and fusion modifies the natural course of anterior disk-osteophyte complex in patients with multilevel cervical spondylotic myelopathy.

SUMMARY OF BACKGROUND DATA

Dorsal migration of the spinal cord is the main purported mechanism of spinal cord decompression following cervical laminectomy and fusion but other potential mechanisms have received scant attention in the literature. This study was conducted to investigate whether cervical laminectomy and fusion affects the size of anterior disk-osteophyte complex.

METHODS

The medical records and radiographic imaging of 44 patients who underwent cervical laminectomy and fusion for cervical spondylotic myelopathy between 2006 and 2013 were analyzed. The size of the anterior disk-osteophyte complex was measured preoperatively and postoperatively on MR images taken at an interval of >3 months apart. A control group consisted of 20 nonoperatively treated advanced cervical spondylosis patients. Patients in the control met the same inclusion and exclusion criteria and also had sequential magnetic resonance imaging (MRI) taken at an interval of >3 months apart.

RESULTS

The nonoperative and operative groups were statistically similar in the pertinent patient demographics and characteristics including sex, age, time to second MRI, size of anterior disk-osteophyte complex on baseline MRI, mean number of levels affected, and percentage of patients with T2 signal change. As expected the mJOA scores were significantly lower in the operative versus nonoperative cohort (13.6 vs. 16.5, P<0.01). A significant decrease in the size of anterior disk osteophyte was observed in the operative group postoperatively (P<0.01). In comparison, there was no statistically significant change in the size of the anterior disk-osteophyte complex in the control group (P>0.05). The magnitude of the change in disk size between the 2 groups was statistically significant (P<0.01).

CONCLUSIONS

The findings of this study suggest that regression of anterior disk-osteophyte complex occurs following cervical laminectomy and fusion, and likely provides another mechanism of spinal cord decompression.

Trends and Cost of Posterior Cervical Fusions With and Without Recombinant Human Bone Morphogenetic Protein-2 in the US Medicare Population

STUDY DESIGN

Retrospective database review.

OBJECTIVE

To analyze and report the trends and cost of posterior cervical fusions (PCFs) with and without off-label recombinant human bone morphogenetic protein-2 (rhBMP-2) in the Medicare population.

METHODS

Patient records from the PearlDiver database were retrospectively reviewed from January 1, 2005, to December 31, 2012, to distinguish individuals who underwent a PCF with or without rhBMP-2. Total numbers, incidence, age, gender, geographic region, reimbursement, and length of stay were analyzed and summarized.

RESULTS

The combined total of non-rhBMP-2 (n = 39 479; 85.51%) and rhBMP-2 PCF (n = 6692; 14.49%) procedures performed between 2005 and 2012 was 46 171. In general, the number of PCFs without rhBMP-2 consistently increased over time, while the number of PCFs with rhBMP-2 had only a slight increase from 2005 to 2012. On average, PCFs without rhBMP-2 were associated with $1197 higher cost than those with rhBMP-2, but the average length of stay was similar (6 days). From 2005 to 2012, the average cost for procedures with and without rhBMP-2 increased by $12 605 and $7291, respectively. The percentage of rhBMP-2 use peaked in 2007 and dwindled until 2010, and declined an additional 2.84% from 2011 to 2012. Multiple age, region, and gender tendencies were observed.

CONCLUSIONS

To our knowledge, this was the first study to use the PearlDiver database to report incidence and cost trends of PCF procedures. This article provides meaningful trend data on PCFs to surgeons and clinicians, researchers, and patients, as well as functions as a beacon for future research questions.

Surgical treatment of severe multilevel circumferential compressive myelopathy of the cervical spine: is circumferential procedure necessary?

OBJECTIVE

To determine the necessity of circumferential decompression and fusion in patients with severe multilevel cervical spondylotic myelopathy with circumferential cord compression.

METHODS

This prospective study involved 51 patients with severe multilevel circumferential cervical myelopathy underwent two-stage circumferential procedure between July 2008 and June 2010. VAS scores, satisfaction surveys and JOA scores and imaging studies were obtained. Twenty-three patients (45.1%) underwent two-stage surgery (group A); the other 28 patients (54.9%) were satisfied with the outcomes after first-stage surgery, and the second-stage surgery was avoided (group B). Age, sex and symptom duration did not differ between the groups.

RESULTS

Patients were followed up for 3-5 years (mean, 42.5 months). In group A, VAS and JOA scores significantly improved from 63.3 and 7.9 to 38.3 and 10.4, respectively, at 3 months after the first-stage operation and 10.2 and 12.7, respectively, at 3 months after the second-stage operation. In group B, the VAS and JOA scores significantly improved from 62.7 and 7.9 to 31.1 and 11.2 respectively, at 3 months and 18.2 and 12.4, respectively at 6 months. Patient satisfaction rate significantly increased from 43.5% after the first-stage operation to 82.6% after the second-stage operation in group A. In group B, this rate was 89.3%. In group A, cervical spine lordosis increased from 12.8° preoperatively to 18.5° (p < .0001) and 19.1° (p > .05) at 3 months after the first-stage and second-stage operations, respectively. In group B, lordosis significantly increased from 12.5° preoperatively to 18.8° at 3 months. The total complication rate did not significantly differ from the rates after a single surgery (either anterior or posterior).

CONCLUSION

Only 45.1% patients required surgery via both approaches. Therefore, a two-stage procedure is a rational choice and safe procedure. If outcomes are unsatisfactory after the first-stage operation, a second-stage operation can be performed.

Cervical Laminectomy with Lateral Mass Screw Fixation in Cervical Spondylotic Myelopathy: Neurological and Sagittal Alignment Outcome: Do We Need Lateral Mass Screws at each Segment?

BACKGROUND

Anterior cervical decompression and fusion is the standard procedure used for treating patients with cervical myelopathy. However, these procedures are associated with complications such as pseudarthrosis, construct failure, and neurological complications. Posterior cervical laminectomy and instrumentation is an alternative procedure to treat multilevel cervical myelopathy. In this study, we raised questions whether instrumentation is required at all levels and whether stabilizing the spine in neutral or lordotic contour with indirect decompression leads to neurological improvement with radiological evidence of anterior decompression. The results of posterior cervical laminectomy and instrumentation with lateral mass screw in terms of radiological and functional outcome in patients with multilevel cervical myelopathy are prospectively evaluated.

MATERIALS AND METHODS

In this prospective study conducted between June 2006 and December 2015, we have evaluated 112 patients with multilevel cervical myelopathy who underwent multilevel cervical laminectomy and instrumentation with lateral mass screw. All patients were evaluated preoperatively and postoperatively with Nurick's grading and Modified Japanese Orthopaedic Association (mJOA) scale for neurological function. Cooper scale and British Medical Research Council grading system for motor function. Curvature index was used to measure the alignment of cervical spine preoperatively and postoperatively. Alignment of the cervical spine was done preoperatively and postoperatively by calculating the curvature index. Axial MRI was used to calculate the severity of compression preoperatively which was calculated as per Singh's criteria and postoperatively to assess the adequacy of decompression at the operated level.

RESULTS

In our study, there were 112 patients including 99 males and 13 females, with mean age of 59.53 years. The mean duration of followup of patients was 33.24 months. In total, cervical laminectomy was performed at 342 levels in 112 patients with an average of 3.05 laminectomies, and in total, 112 lateral mass screws were inserted. On postoperative followup, the mJOA and Nurick's grading showed improvement in all cases as compared to preoperative findings. The mean mJOA improved significantly from 8.56 preoperatively to 13.57 postoperatively (P < 0.001). The mean Nurick's grading also improved significantly from 2.59 preoperatively to 0.66 postoperatively (P < 0.001). The mean Cooper scale also showed significant improvement in both upper and lower limbs postoperatively (P < 0.001). The mean preoperative Cooper scale was 1.75 and postoperative was 0.31 for upper limbs, and the mean Cooper scale was 2.14 preoperatively and 0.56 postoperatively for lower limbs. X-rays done on routine followups showed good alignment of the cervical spine with maintenance of curvature index in all patients. The mean grade of compression as seen on preoperative MRI was 2.46 which reduced significantly postoperatively to 0.16 (P < 0.001).

CONCLUSION

The multilevel cervical laminectomy and instrumentation with lateral mass screw for multilevel cervical myelopathy is a safe technique that provides decompression of the spinal cord, prevents the development of kyphotic spinal deformity and posterior tension band of the spinal cord as associated with laminoplasty or uninstrumented laminectomy.

Reoperation rates for symptomatic nonunions in posterior cervicothoracic fusions with and without bone morphogenetic protein in a cohort of 450 patients

OBJECTIVE

Fusions across the cervicothoracic junction have been challenging because of the large biomechanical forces exerted resulting in frequent reoperations for nonunions. The objective of this study was to investigate a retrospective cohort using chart review of posterior cervicothoracic spine fusions with and without bone morphogenetic protein (BMP) and to determine the reoperation rates for symptomatic nonunions in both groups.

METHODS

Between January 2009 and September 2013, posterior cervicothoracic spine fusion cases were identified from a large spine registry (Kaiser Permanente). Demographics, diagnoses, operative times, lengths of stay, and reoperations were extracted from the registry. Reoperations for symptomatic nonunions were adjudicated via chart review. Logistic regression was used to estimate odds ratios and 95% confidence intervals. Kaplan-Meier curves for the non-BMP and BMP groups were generated and compared using the log-rank test.

RESULTS

In this cohort there were 450 patients (32.7% with BMP) with a median follow-up of 1.4 years (interquartile range [IQR] 0.5–2.7 years). Kaplan-Meier curves showed no significant difference in reoperation rates for nonunions using the log-rank test (p = 0.088). In a subset of patients with more than 1 year of follow-up, 260 patients were identified (43.1% with BMP) with a median follow-up duration of 2.4 years (IQR 1.6–3.3 years). There was no statistically significant difference in the symptomatic operative nonunion rates for posterior cervicothoracic fusions with and without BMP (0.0% vs 2.7%, respectively; p = 0.137) for more than 1 year of follow-up.

CONCLUSIONS

This study presents the largest series of patients using BMP in posterior cervicothoracic spine fusions. Reoperation rates for symptomatic nonunions with more than 1 year of follow-up were 0% with BMP and 2.7% without BMP. No statistically significant difference in the reoperation rates for symptomatic nonunions with or without BMP was found.

Posterior Cervical Fusion With Recombinant Human Bone Morphogenetic Protein-2: Complications and Fusion Rate at Minimum 2-Year Follow-Up

STUDY DESIGN

Retrospective case series.

OBJECTIVE

The purpose of this study was to determine the fusion rate and evaluate the complications associated with the application of recombinant human bone morphogenetic protein-2 (rhBMP-2) in posterior cervical fusion.

SUMMARY OF BACKGROUND DATA

The rates of fusion and complications associated with the use of rhBMP-2 in posterior cervical fusion is unclear, though recent work has shown up to a 100% fusion rate.

METHODS

We independently reviewed consecutive series of patients who underwent posterior cervical, occipitocervical, or cervicothoracic instrumented fusion augmented with rhBMP-2. Two surgeons at a tertiary-referral, academic medical center performed all operations, and each patient had a minimum of 2-year follow-up. Fusion status was determined by bony bridging on computed tomography scans, absence of radiolucency around instrumentation, and absence of motion on lateral flexion/extension radiographs.

RESULTS

Fifty-seven patients with a mean age of 56.7±13.2 years and mean follow-up of 37.7±20.6 months were analyzed. Forty-eight patients (84.2%) had undergone previous cervical surgery, and 42.1% had a preexisting nonunion. Constructs spanned 5.6±2.6 levels; 19.3% involved the occiput, whereas 61.4% crossed the cervicothoracic junction. The mean rhBMP-2 dose was 21.1±8.7 mg per operation. Iliac crest autograft was used for 29.8% of patients. Six patients (10.5%) experienced nonunion; only 2 required revision. In each case of nonunion, instrumentation crossed the occipitocervical or cervicothoracic junction. However, none of the analyzed variables was statistically associated with nonunion. Fourteen patients (24.6%) suffered complications, with 7 requiring additional surgery.

CONCLUSIONS

The observed fusion rate of rhBMP-2-augmented posterior cervical, occipitocervical, and cervicothoracic fusions was 89.5%. This reflects the complicated nature of the patients included in the current study and demonstrates that rhBMP-2 cannot always overcome the biomechanical challenges entailed in spanning the occipitocervical or cervicothoracic junction.

Diagnosis and neurologic status as predictors of surgical site infection in primary cervical spinal surgery

BACKGROUND CONTEXT

Surgical site infection (SSI) incidence after cervical spinal surgery ranges from 0.1% to 17%. Although the general risk factors for SSI have been discussed, the relationship of neurologic status and trauma to SSI has not been explicitly explored.

PURPOSE

This study aimed to study associated risk factors and to report the incidence of SSI in patients who have undergone cervical spinal surgery with the following four preoperative diagnoses: (1) degenerative disease with no myelopathy (MP), (2) degenerative disease with MP, (3) traumatic cervical injury without spinal cord injury (SCI), (4) traumatic cervical injury with SCI. We hypothesize that SSI incidence would increase from Group (1) to Group (4).

STUDY DESIGN

Retrospective database analysis was carried out.

PATIENTS SAMPLE

We used International Classification of Diseases codes to identify the four groups of patients in the U.S. Nationwide Inpatient Sample (NIS) from the years 2000 to 2011. We complemented this study with a similar search in our institutional database (ID) from the years 2000 to 2013. Patients with concomitant congenital deformity, infection, inflammatory disease, and neoplasia were excluded, as were revision surgeries.

OUTCOME MEASURES

The primary outcome studied was the occurrence of SSI. Statistical analyses included bivariate comparisons and chi-square distribution of demographic data and multivariable regression for demographic, surgical, and outcome variables.

RESULTS

A total of 1,247,281 and 5,540 patients met inclusion criteria in the NIS database and the ID, respectively. Overall SSI incidence was 0.73% (NIS) versus 1.75% (ID). Surgical site infection incidence increased steadily from 0.52% in Group (1) to 1.97% in Group (4) in the NIS data and from 0.88% to 5.54% in the ID. Differences between diagnostic groups and cohorts reached statistical significance. Surgical site infection was predicted significantly by status (odds ratio [OR] 1.69, p<.0001) and trauma (OR 1.30, p=.0003) in the NIS data. Other significant predictors included the following: approach, number of levels fused, female gender, black race, medium size hospital, rural hospital, large hospital, western US hospital and Medicare coverage. In the ID, only trauma (OR 2.11, p=.03) reached significance when accounting for comorbidities.

CONCLUSIONS

Both primary diagnosis (trauma vs. degenerative) and neurologic status (MP or SCI) were found to be strong and independent predictors of SSI in cervical spine surgery.

Reoperation rates for symptomatic nonunions in posterior cervical (subaxial) fusions with and without bone morphogenetic protein in a cohort of 1158 patients

OBJECTIVE

Bone morphogenetic protein (BMP) was first approved in 2002 for use in single-level anterior lumbar fusions as an alternative to iliac crest grafts. Subsequent studies have concluded that BMP provides superior fusions rates and therefore reduces reoperations for nonunions. The purpose of this study was to determine the reoperation rates for symptomatic nonunions in posterior cervical (subaxial) spinal fusions with and without the use of BMP and to determine if the nonunion rates are statistically significantly different between the two groups.

METHODS

Between January 2009 and September 2013, the authors identified 1158 posterior cervical spinal fusion cases in the subaxial spine (C2–7) from a large spine registry (Kaiser Permanente). Patient characteristics, diagnoses, operative times, lengths of stay, and reoperations were extracted from the registry. Reoperations for symptomatic nonunions were adjudicated via chart review. Logistic regression was conducted to produce estimates of odds ratios (OR) and 95% confidence intervals (CIs). Kaplan-Meier curves for the non-BMP and BMP groups were generated and compared using the log-rank test.

RESULTS

In this cohort there were 1158 patients (19.3% with BMP) with a median follow up of 1.7 years (interquartile range [IQR] 0.7–2.9 years) and median duration to operative nonunion of 0.63 years (IQR 0.44–1.57 years). Kaplan-Meier curves showed no significant difference in reoperation rates for nonunions using the log-rank test (p = 0.179). In a subset of patients with more than 1 year of follow-up, 788 patients were identified (22.5% with BMP) with a median follow-up duration of 2.5 years (IQR 1.7–3.4 years) and a median time to operative nonunion of 0.73 years (IQR 0.44–1.57 years). There was no statistically significant difference in the symptomatic operative nonunion rates for posterior cervical (subaxial) fusions with BMP compared with non-BMP (1.1% vs 0.7%; crude OR 1.73, 95% CI 0.32–9.55, p = 0.527) for more than 1 year of follow-up.

CONCLUSIONS

This study presents the largest series of patients using BMP in posterior cervical (subaxial) spinal fusions. Reoperation rates for symptomatic nonunions with more than 1 year of follow-up were found to be 1.1% with BMP and 0.7% without BMP. There was no significant difference in the reoperation rates for symptomatic nonunions with or without BMP.

Exploratory meta-analysis on dose-related efficacy and morbidity of bone morphogenetic protein in spinal arthrodesis surgery

OBJECT

Bone morphogenetic protein (BMP) is frequently used for spinal arthrodesis procedures in an "off-label" fashion. Whereas complications related to BMP usage are well recognized, the role of dosage is less clear. The objective of this meta-analysis was to assess dose-dependent effectiveness (i.e., bone fusion) and morbidity of BMP used in common spinal arthrodesis procedures. A quantitative exploratory meta-analysis was conducted on studies reporting fusion and complication rates following anterior cervical discectomy and fusion (ACDF), posterior cervical fusion (PCF), anterior lumbar interbody fusion (ALIF), transforaminal lumbar interbody fusion (TLIF), posterior lumbar interbody fusion (PLIF), and posterolateral lumbar fusion (PLF) supplemented with BMP.

METHODS

A literature search was performed to identify studies on BMP in spinal fusion procedures reporting fusion and/or complication rates. From the included studies, a database for each spinal fusion procedure, including patient demographic information, dose of BMP per level, and data regarding fusion rate and complication rates, was created. The incidence of fusion and complication rates was calculated and analyzed as a function of BMP dose. The methodological quality of all included studies was assessed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Data were analyzed using a random-effects model. Event rates are shown as percentages, with a 95% CI.

RESULTS

Forty-eight articles met the inclusion criteria: ACDF (n = 7), PCF (n = 6), ALIF (n = 9), TLIF/PLIF (n = 17), and PLF (n = 9), resulting in a total of 5890 patients. In ACDF, the lowest BMP concentration analyzed (0.2-0.6 mg/level) resulted in a fusion rate similar to the highest dose (1.1-2.1 mg/level), while permitting complication rates comparable to ACDF performed without BMP. The addition of BMP to multilevel constructs significantly (p < 0.001) increased the fusion rate (98.4% [CI 95.4%-99.4%]) versus the control group fusion rate (85.8% [CI 77.4%-91.4%]). Studies on PCF were of poor quality and suggest that BMP doses of ≤ 2.1 mg/level resulted in similar fusion rates as higher doses. Use of BMP in ALIF increased fusion rates from 79.1% (CI 57.6%-91.3%) in the control cohort to 96.9% (CI 92.3%-98.8%) in the BMP-treated group (p < 0.01). The rate of complications showed a positive correlation with the BMP dose used. Use of BMP in TLIF had only a minimal impact on fusion rates (95.0% [CI 92.8%-96.5%] vs 93.0% [CI 78.1%-98.0%] in control patients). In PLF, use of ≥ 8.5 mg BMP per level led to a significant increase of fusion rate (95.2%; CI 90.1%-97.8%) compared with the control group (75.3%; CI 64.1%-84.0%, p < 0.001). BMP did not alter the rate of complications when used in PLF.

CONCLUSIONS

The BMP doses used for various spinal arthrodesis procedures differed greatly between studies. This study provides BMP dosing recommendations for the most common spine procedures.

Cervical spondylotic myelopathy surgical trial: randomized, controlled trial design and rationale

BACKGROUND

Cervical spondylotic myelopathy (CSM) is the most common cause of spinal cord dysfunction in the world. There are significant practice variation and uncertainty as to the optimal surgical approach for treating CSM.

OBJECTIVE

To determine whether ventral surgery is associated with superior Short Form-36 Physical Component Summary outcome at the 1-year follow-up compared with dorsal (laminectomy/fusion or laminoplasty) surgery for the treatment of CSM, to investigate whether postoperative sagittal balance is an independent predictor of overall outcome, and to compare health resource use for ventral and dorsal procedures.

METHODS

The study is a randomized, controlled trial with a nonrandomized arm for patients who are eligible but decline randomization. Two hundred fifty patients (159 randomized) with CSM from 11 sites will be recruited over 18 months. The primary outcome is the Short Form-36 Physical Component Summary score. Secondary outcomes include disease-specific outcomes, overall health-related quality of life (EuroQOL 5-dimension questionnaire), and health resource use.

EXPECTED OUTCOMES

This will be the first randomized, controlled trial to compare directly the health-related quality-of-life outcomes for ventral vs dorsal surgery for treating CSM.

DISCUSSION

A National Institutes of Health-funded (1R13AR065834-01) investigator meeting was held before the initiation of the trial to bring multiple stakeholders together to finalize the study protocol. Study investigators, coordinators, and major stakeholders were able to attend and discuss strengths of, limitations of, and concerns about the study. The final protocol was approved for funding by the Patient-Centered Outcomes Research Institute (CE-1304-6173). The trial began enrollment on April 1, 2014.

C5 nerve root palsy following decompression of the cervical spine

C5 nerve root palsy is a rare and potentially debilitating complication of cervical spine surgery. Currently, however, there are no guidelines to help surgeons to prevent or treat this complication.

We carried out a systematic review of the literature to identify the causes of this complication and options for its prevention and treatment. Searches of PubMed, Embase and Medline yielded 60 articles for inclusion, most of which addressed C5 palsy as a complication of surgery. Although many possible causes were given, most authors supported posterior migration of the spinal cord with tethering of the nerve root as being the most likely.

Early detection and prevention of a C5 nerve root palsy using neurophysiological monitoring and variations in surgical technique show promise by allowing surgeons to minimise or prevent the incidence of C5 palsy. Conservative treatment is the current treatment of choice; most patients make a full recovery within two years.

Cite this article: Bone Joint J 2014;96-B:950–5.

Lateral mass screw fixation in the cervical spine: a systematic literature review

BACKGROUND

Lateral mass screw fixation with plates or rods has become the standard method of posterior cervical spine fixation and stabilization for a variety of surgical indications. Despite ubiquitous usage, the safety and efficacy of this technique have not yet been established sufficiently to permit "on-label" U.S. Food and Drug Administration approval for lateral mass screw fixation systems. The purpose of this study was to describe the safety profile and effectiveness of such systems when used in stabilizing the posterior cervical spine.

METHODS

A systematic search was conducted in MEDLINE and the Cochrane Collaboration Library for articles published from January 1, 1980, to December 1, 2011. We included all articles evaluating safety and/or clinical outcomes in adult patients undergoing posterior cervical subaxial fusion utilizing lateral mass instrumentation with plates or rods for degenerative disease (spondylosis), trauma, deformity, inflammatory disease, and revision surgery that satisfied our a priori inclusion and exclusion criteria.

RESULTS

Twenty articles (two retrospective comparative studies and eighteen case series) satisfied the inclusion and exclusion criteria and were included. Both of the comparative studies involved comparison of lateral mass screw fixation with wiring and indicated that the risk of complications was comparable between treatments (range, 0% to 7.1% compared with 0% to 6.3%, respectively). In one study, the fusion rate reported in the screw fixation group (100%) was similar to that in the wiring group (97%). Complication risks following lateral mass screw fixation were low across the eighteen case series. Nerve root injury attributed to screw placement occurred in 1.0% (95% confidence interval, 0.3% to 1.6%) of patients. No cases of vertebral artery injury were reported. Instrumentation complications such as screw or rod pullout, screw or plate breakage, and screw loosening occurred in <1% of the screws inserted. Fusion was achieved in 97.0% of patients across nine case series.

CONCLUSIONS

The risks of complications were low and the fusion rate was high when lateral mass screw fixation was used in patients undergoing posterior cervical subaxial fusion. Nerve root injury attributed to screw placement occurred in only 1% of 1041 patients. No cases of vertebral artery injury were identified in 758 patients. Screw or rod pullout, screw or plate breakage, and screw loosening occurred in <1% of the screws inserted.

Retrospective cost analysis of cervical laminectomy and fusion versus cervical laminoplasty in the treatment of cervical spondylotic myelopathy

Background

Cervical laminoplasty (CLP) and posterior cervical laminectomy and fusion (CLF) are well-established surgical procedures used in the treatment of cervical spondylotic myelopathy (CSM). In situations of clinical equipoise, an influential factor in procedural decision making could be the economic effect of the chosen procedure. The object of this study is to compare and analyze the total hospital costs and charges pertaining to patients undergoing CLP or CLF for the treatment of CSM.

Methods

We performed a retrospective review of 81 consecutive patients from a single institution; 55 patients were treated with CLP and 26 with CLF. CLP was performed via the double-door allograft technique that does not require implants, whereas laminectomy fusion procedures included metallic instrumentation. We analyzed 10,682 individual costs (HC) and charges (HCh) for all patients, as obtained from hospital accounting data. The Current Procedural Terminology codes were used to estimate the physicians’ fees as such fees are not accounted for via hospital billing records. Total cost (TC) therefore equaled the sum of the hospital cost and the estimated physicians’ fees.

Results

The mean length of stay was 3.7 days for CLP and 5.9 days for CLF (P < .01). There were no significant differences between the groups with respect to age, gender, previous surgical history, and medical insurance. The TC mean was $17,734 for CLP and $37,413 for CLF (P < .01). Mean HCh for CLP was 42% of that for CLF, and therefore the mean charge for CLF was 238% of that for CLP (P < .01). Mean HC was $15,426 for CLP and $32,125 for CLF (P < .01); the main contributor was implant cost (mean $2582).

Conclusions

Our study demonstrates that, in clinically similar populations, CLP results in reduced length of stay, TC, and hospital charges. In CSM cases requiring posterior decompression, we demonstrate CLP to be a less costly procedure. However, in the presence of neck pain, kyphotic deformity, or gross instability, this procedure may not be sufficient and posterior CLF may be required.

Functional outcome instruments used for cervical spondylotic myelopathy: interscale correlation and prediction of preference-based quality of life

BACKGROUND CONTEXT

There is limited literature comparing different functional outcome measures used for cervical spondylotic myelopathy (CSM).

PURPOSE

To determine the correlation among five functional outcome measures used in CSM patient assessment and their ability to predict preference-based quality of life (QOL).

STUDY DESIGN/SETTING

Prospective observational study.

PATIENT SAMPLE

Patients, aged 40 to 85 years, with CSM and cervical spinal cord compression at two or more levels from degenerative spondylosis were enrolled from seven sites over a 2-year period.

OUTCOME MEASURES

The modified Japanese Orthopedic Association scale, Oswestry neck disability index (Oswestry NDI or Oswestry), Nurick scale, norm-based short-form 36 physical component summary, and EuroQol-5D (EQ-5D) were collected.

METHODS

The Jean and David Wallace foundation provided funding for this study. Cervical spondylotic myelopathy patients undergoing either anterior or posterior surgery were prospectively followed with five different functional outcome measures over 1 year. Correlations among scales were tested using the Spearman rank correlation test. The sensitivity and specificity of each scale for predicting the global index of the EQ-5D were determined, and receiver-operating characteristic analysis was used to compare each scale's ability to discriminate QOL.

RESULTS

A total of 106 patients were initially enrolled; 103 were operated on for CSM and followed for 1 year. Their ages ranged from 40 to 82 years (mean 61.9), and 61.3% were men. Correlations among the various functional outcome instruments were all highly significant (p<.001), but the degree of correlation varied greatly. Correlation between the EQ-5D scale and the Nurick scale was the least (Spearman rho 0.5539); correlation was the highest with the Oswestry NDI (Spearman rho 0.8306). The Oswestry NDI also had the greatest ability to discriminate favorable from adverse QOL compared with the other outcome instruments (p=.023).

CONCLUSIONS

Preference-based quality-of-life instruments, such as the EQ-5D, are important measures for studying spinal disorders. Among the various commonly used outcome instruments for CSM, the Oswestry NDI is the most predictive of preference-based QOL.

Ventral fusion versus dorsal fusion: determining the optimal treatment for cervical spondylotic myelopathy

Cervical spondylotic myelopathy (CSM) often can be surgically treated by either ventral or dorsal decompression and fusion. However, there is a lack of high-level evidence on the relative advantages and disadvantages for these treatments of CSM. The authors' goal was to provide a comprehensive review of the relative benefits of ventral versus dorsal fusion in terms of quality of life (QOL) outcomes, complications, and costs. They reviewed 7 studies on CSM published between 2003 and 2013 and summarized the findings for each category. Both procedures have been shown to lead to statistically significant improvement in clinical outcomes for patients. Ventral fusion surgery has been shown to yield better QOL outcomes than dorsal fusion surgery. Complication rates for ventral fusion surgery range from 11% to 13.6%, whereas those for dorsal fusion surgery range from 16.4% to 19%. Larger randomized controlled trials are needed, with particular emphasis on QOL and minimum clinically important differences.

Predictors of outcome in patients with degenerative cervical spondylotic myelopathy undergoing surgical treatment: results of a systematic review

PURPOSE

To conduct a systematic review of the literature to determine important clinical predictors of surgical outcome in patients with cervical spondylotic myelopathy (CSM).

METHODS

A literature search was performed using MEDLINE, MEDLINE in Process, EMBASE and Cochrane Database of Systematic Reviews. Selected articles were evaluated using a 14-point modified SIGN scale and classified as either poor (<7), good (7-9) or excellent (10-14) quality of evidence. For each study, the association between various clinical factors and surgical outcome, evaluated by the (modified) Japanese Orthopaedic Association scale (mJOA/JOA), Nurick score or other measures, was defined. The results from the EXCELLENT studies were compared to the combined results from the EXCELLENT and GOOD studies which were compared to the results from all the studies.

RESULTS

The initial search yielded 1,677 citations. Ninety-one of these articles, including three translated from Japanese, met the inclusion and exclusion criteria and were graded. Of these, 16 were excellent, 38 were good and 37 were poor quality. Based on the excellent studies alone, a longer duration of symptoms was associated with a poorer outcome evaluated on both the mJOA/JOA scale and Nurick score. A more severe baseline score was related with a worse outcome only on the mJOA/JOA scale. Based on the GOOD and EXCELLENT studies, duration of symptoms and baseline severity score were consistent predictors of mJOA/JOA, but not Nurick. Age was an insignificant predictor of outcome on any of the functional outcomes considered.

CONCLUSION

The most important predictors of outcome were preoperative severity and duration of symptoms. This review also identified many other valuable predictors including signs, symptoms, comorbidities and smoking status.

Cervical lateral mass screw fixation without fluoroscopic control: analysis of risk factors for complications associated with screw insertion

OBJECTIVE

To examine the outcome of cervical lateral mass screw fixation focusing on analysis of the risk factors for screw-related complications.

METHODS

Ninety-four patients who underwent posterior cervical fixation with a total of 457 lateral mass screws were included in the study. The lateral mass screws were placed using a modified Magerl method. Computed tomographic (CT) images were taken in the early postoperative period in all patients, and the screw trajectory angle was measured on both axial and sagittal plane images.

RESULTS

In the postoperative CT analysis for the screw trajectory, 56.5 % of the screws were directed within the acceptable range (within 21-40° on both axial and sagittal planes). As intraoperative screw-associated complications, 9.6 % of the screws were found to contact with or breach the vertebral artery foramen. In this group, the screw trajectory angle on axial plane was significantly lower than in the group without contact. Facet violation was observed in 13 screws (2.8 %). This complication was associated with a significantly lower trajectory angles in the sagittal plane, predominantly at C6 level (69.2 %). In the patient chart review, no serious neurovascular injuries were documented.

CONCLUSIONS

In the analysis of potential risk factors for violation of the VA foramen as well as FV during screw insertion, the former incidence was significantly related to the screw trajectory angle (lack of lateral angulation) in the axial plane, while the latter incidence was related to a poor screw trajectory angle in the sagittal plane.

Adjacent-level range of motion and intradiscal pressure after posterior cervical decompression and fixation: an in vitro human cadaveric model

STUDY DESIGN

This in vitro human cadaveric study measured adjacent-level kinematics after posterior cervical decompression and fixation.

OBJECTIVE

Quantify adjacent-level changes in range of motion (ROM) and intradiscal pressure after posterior cervical decompression and fixation.

SUMMARY OF BACKGROUND DATA

Optimal length of instrumentation after posterior decompression is unclear. Longer posterior cervical fixation constructs may increase the risk of adjacent-segment degeneration.

METHODS

Eight cervicothoracic spines were evaluated intact, with C3-C6 laminectomy, C3-C6 laminectomy + C3-C6 fixation, C3-C6 laminectomy + C3-C7 fixation, C3-C7 laminectomy, C3-C7 laminectomy + C3-C7 fixation, C3-C7 laminectomy + C2-C7 fixation, C3-C7 laminectomy + C3-T2 fixation, and C3-C7 laminectomy + C2-T2 fixation. Testing included intact moments (± 2.0 N·m) in flexion/extension, axial rotation, and lateral bending, with quantification of ROM at C2-C3, C6-C7, and C7-T1 normalized to the intact spine. Intradiscal pressures were also measured at each level.

RESULTS

For the C3-C6 laminectomy group, there were no differences in adjacent-level flexion/extension ROM or intradiscal pressure based on construct length, except at C6-C7, where ROM was significantly decreased when fixation was extended to C7 (P < 0.05). After C3-C7 laminectomy and reconstruction, the greatest increase in C2-C3 flexion/extension ROM and intradiscal pressure occurred in the C3-T2 fixation subgroup (ROM: 348% [P < 0.05]; intradiscal pressure: 319 ± 243 psi [pounds per square inch] vs. 65 ± 41 psi intact [P < 0.05]). At C7-T1, the greatest increase in flexion/extension ROM and intradiscal pressure occurred after C2-C7 fixation (ROM: 531% [P < 0.05]; intradiscal pressure: 152 ± 83 psi vs. 21 ± 14 psi intact [P < 0.05]).

CONCLUSION

For C3-C6 laminectomy, instrumentation to C7 significantly decreased flexion/extension ROM and intradiscal pressure at C6-C7 without significantly increasing either measure at C2-C3 or C7-T1 relative to C3-C6 fixation. In the setting of a C3-C7 laminectomy, when instrumenting to either C2 or T2, consideration should be given to including both levels within these constructs.

Operative outcomes for cervical degenerative disease: a review of the literature

To date, several studies were conducted to find which procedure is superior to the others for the treatment of cervical myelopathy. The goal of surgical treatment should be to decompress the nerves, restore the alignment of the vertebrae, and stabilize the spine. Consequently, the treatment of cervical degenerative disease can be divided into decompression of the nerves alone, fixation of the cervical spine alone, or a combination of both. Posterior approaches have historically been considered safe and direct methods for cervical multisegment stenosis and lordotic cervical alignment. On the other hand, anterior approaches are indicated to the patients with cervical compression with anterior factors, relatively short-segment stenosis, and kyphotic cervical alignment. Recently, posterior approach is widely applied to several cervical degenerative diseases due to the development of various instruments. Even if it were posterior approach or anterior approach, each would have its complication. There is no Class I or II evidence to suggest that laminoplasty is superior to other techniques for decompression. However, Class III evidence has shown equivalency in functional improvement between laminoplasty, anterior cervical fusion, and laminectomy with arthrodesis. Nowadays, each surgeon tends to choose each method by evaluating patients' clinical conditions.

Operative outcomes for cervical myelopathy and radiculopathy

Cervical spondylotic myelopathy and radiculopathy are common disorders which can lead to significant clinical morbidity. Conservative management, such as physical therapy, cervical immobilisation, or anti-inflammatory medications, is the preferred and often only required intervention. Surgical intervention is reserved for those patients who have intractable pain or progressive neurological symptoms. The goals of surgical treatment are decompression of the spinal cord and nerve roots and deformity prevention by maintaining or supplementing spinal stability and alleviating pain. Numerous surgical techniques exist to alleviate symptoms, which are achieved through anterior, posterior, or circumferential approaches. Under most circumstances, one approach will produce optimal results. It is important that the surgical plan is tailored to address each individual's unique clinical circumstance. The objective of this paper is to analyse the major surgical treatment options for cervical myelopathy and radiculopathy focusing on outcomes and complications.

Performing a Cost Analysis in Spine Outcomes Research

BACKGROUND:

Medical cost analysis is increasingly important, but the methodology is complex and varied.

OBJECTIVE:

To illustrate how different cost analysis methodologies influence conclusions generated from data from a prospective nonrandomized trial for treatment of cervical spondylotic myelopathy.

METHODS:

Patients 40 to 85 years of age with degenerative cervical spondylotic myelopathy were enrolled from 7 sites over 2 years (2007–2009). Patients were treated with ventral or dorsal fusion surgery, and outcomes were measured to 1 year postoperatively. A hospital-based cost analysis was performed using Medicare cost-to-charge ratios (CCRs) multiplied by hospital charges from the index hospitalization (CCR method). A society-based cost analysis was performed by estimating costs from the index hospitalization using Medicare coding reimbursement (the Medicare reimbursement method). A separate outpatient cost analysis was performed on a subset of 20 patients.

RESULTS:

Of the 85 patients analyzed, 72 had 1-year follow-up. The CCR method showed a difference in upfront direct costs between the dorsal and ventral approaches ($27 942 ± 14 220 vs $21 563 ± 8721; P = .02). Overall upfront direct costs with the Medicare reimbursement method were not different. With the CCR method, the ventral approach dominates an incremental cost-effectiveness ratio analysis. With the Medicare reimbursement method, the incremental cost-effectiveness ratio for ventral surgery is $34 533, the cost of 1 additional quality-adjusted life-year gained by using ventral instead of dorsal surgery. In the subanalysis, outpatient costs were less after ventral surgery than dorsal surgery ($1997 ± 1211 vs $4734 ± $2874; P = .006).

CONCLUSION:

The choice of cost methodology may substantially influence the final results of an economic study.

A Prospective, Randomized Trial Comparing Expansile Cervical Laminoplasty and Cervical Laminectomy and Fusion for Multilevel Cervical Myelopathy

BACKGROUND:

Controversy exists as to the best posterior operative procedure to treat multilevel compressive cervical spondylotic myelopathy.

OBJECTIVE:

To determine clinical, radiological, and patient satisfaction outcomes between expansile cervical laminoplasty (ECL) and cervical laminectomy and fusion (CLF).

METHODS:

We performed a prospective, randomized study of ECL vs CLF in patients suffering from cervical spondylotic myelopathy. End points included the Short Form-36, Neck Disability Index, Visual Analog Scale, modified Japanese Orthopedic Association score, Nurick score, and radiographic measures.

RESULTS:

A survey of academic North American spine surgeons (n = 30) demonstrated that CLF is the most commonly used (70%) posterior procedure to treat multilevel spondylotic cervical myelopathy. A total of 16 patients were randomized: 7 to CLF and 9 to ECL. Both groups showed improvements in their Nurick grade and Japanese Orthopedic Association score postoperatively, but only the improvement in the Nurick grade for the ECL group was statistically significant (P &lt; .05). The cervical range of motion between C2 and C7 was reduced by 75% in the CLF group and by only 20% in the ECL group in a comparison of preoperative and postoperative range of motion. The overall increase in canal area was significantly (P &lt; .001) greater in the CLF group, but there was a suggestion that the adjacent level was more narrowed in the CLF group in as little as 1 year postoperatively.

CONCLUSION:

In many respects, ECL compares favorably to CLF. Although the patient numbers were small, there were significant improvements in pain measures in the ECL group while still maintaining range of motion. Restoration of spinal canal area was superior in the CLF group.

Does smoking influence fusion rates in posterior cervical arthrodesis with lateral mass instrumentation?

BACKGROUND

Smoking is associated with reduced fusion rates after anterior cervical decompression and arthrodesis procedures. Posterior cervical arthrodesis procedures are believed to have a higher fusion rate than anterior procedures.

QUESTIONS/PURPOSES

We asked whether smoking (1) would reduce the fusion rate in posterior cervical procedures; and (2) be associated with increased pain, decreased activity level, and a decreased rate of return of work as compared with nonsmokers.

METHODS

We retrospectively reviewed 158 patients who had a posterior cervical fusion with lateral mass instrumentation and iliac crest bone grafting between 2003 and 2008. Fusion rates and Odom Criteria grades were compared among smokers and nonsmokers. The minimum followup was 3 months (average, 14.5 months; range, 3-72 months).

RESULTS

Smokers and nonsmokers had similar fusion rates (100%). Although 80% of patients had Odom Criteria Grade I or II, smokers were five times more likely to have Grade III or IV with considerable limitation of physical activity. Age, gender, and diagnosis did not influence fusion rates or the Odom Criteria grade.

CONCLUSIONS

In contrast to the effect of smoking on anterior cervical fusion, we found smoking did not decrease posterior cervical fusion with lateral mass instrumentation and iliac crest bone grafting. Posterior cervical fusion with lateral mass instrumentation should be considered over anterior procedures in smokers if the abnormality can appropriately be addressed from a posterior approach.

LEVEL OF EVIDENCE

Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Laminoplasty versus laminectomy and fusion for multilevel cervical spondylotic myelopathy

BACKGROUND

Cervical spondylotic myelopathy is increasingly prevalent in the elderly and is the leading cause of spinal cord dysfunction in this population. Laminectomy with fusion and laminoplasty halt progression of myelopathy in these patients; however, both procedures have well-documented complications and associated morbidity and it is unclear which might be most advantageous.

QUESTIONS/PURPOSES

We therefore compared the pain, function and alignment of patients who underwent laminectomy with fusion to those with laminoplasty for the treatment of multilevel cervical spondylotic myelopathy.

METHODS

We performed a retrospective matched cohort analysis on all 121 patients from 2002 to 2007 who underwent laminectomy with fusion (82) or laminoplasty (39) for multilevel cervical spondylotic myelopathy. We determined change in preoperative and postoperative sagittal alignment using Cobb measurement, development of junctional stenosis, and subjective improvements in pain and gait. Complications were recorded for both cohorts.

RESULTS

The majority of patients in both cohorts reported improvements in pain and gait postoperatively. There were seven complications in the laminectomy and fusion cohort (9%) with two patients requiring formal revision surgery (2%). There were five complications in the laminoplasty cohort (13%) with two formal revision procedures (5%).

CONCLUSIONS

Patients in both the laminectomy with fusion and laminoplasty cohorts reported similar functional improvements after treatment for cervical spondylotic myelopathy. Prospective randomized control trials are needed to determine whether one procedure is truly superior.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Increased in-hospital complications after primary posterior versus primary anterior cervical fusion

BACKGROUND

Although anterior (ACDF) and posterior cervical fusion (PCDF) are relatively common procedures and both are associated with certain complications, the relative frequency and severity of these complications is unclear. Since for some patients either approach might be reasonable it is important to know the relative perioperative risks for decision-making.

QUESTIONS/PURPOSES

The purposes of this study were to: (1) characterize the patient population undergoing ACDF and PCDF; (2) compare perioperative complication rates; (3) determine independent risk factors for adverse perioperative events; and (4) aid in surgical decision-making in cases in which clinical equipoise exists between anterior and posterior cervical fusion procedures.

METHODS

The National Inpatient Sample was used and entries for ACDF and PCDF between 1998 and 2006 were analyzed. Demographics and complication rates were determined and regression analysis was performed to identify independent risk factors for mortality after ACDF and PCDF.

RESULTS

ACDF had a shorter length of stay and their procedures were more frequently performed at nonteaching institutions. The incidence of complications and mortality was 4.14% and 0.26% among patients undergoing ACDF and 15.35% and 1.44% for patients undergoing PCDF, respectively. When controlling for overall comorbidity burden and other demographic variables, PCDF was associated with a twofold increased risk of a fatal outcome compared with ACDF. Pulmonary, circulatory, and renal disease were associated with the highest odds for in-hospital mortality.

CONCLUSIONS

PCDF procedures were associated with higher perioperative rates of complications and mortality compared with ACDF surgeries. Despite limitations, these data should be considered in cases in which clinical equipoise exists between both approaches.

LEVEL OF EVIDENCE

Level II, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.

Comparative Effectiveness of Ventral vs Dorsal Surgery for Cervical Spondylotic Myelopathy

BACKGROUND:

Cervical spondylotic myelopathy (CSM) is the most common cause of spinal cord dysfunction.

OBJECTIVE:

To determine the feasibility of a randomized clinical trial comparing the clinical effectiveness and costs of ventral vs dorsal decompression with fusion surgery for treating CSM.

METHODS:

A nonrandomized, prospective, clinical pilot trial was conducted. Patients ages 40 to 85 years with degenerative CSM were enrolled at 7 sites over 2 years (2007–2009). Outcome assessments were obtained preoperatively and at 3 months, 6 months, and 1 year postoperatively. A hospital-based economic analysis used costs derived from hospital charges and Medicare cost-to-charge ratios.

RESULTS:

The pilot study enrolled 50 patients. Twenty-eight were treated with ventral fusion surgery and 22 with dorsal fusion surgery. The average age was 61.6 years. Baseline demographics and health-related quality of life (HR-QOL) scores were comparable between groups; however, dorsal surgery patients had significantly more severe myelopathy (P &lt; .01). Comprehensive 1-year follow-up was obtained in 46 of 50 patients (92%). Greater HR-QOL improvement (Short-Form 36 Physical Component Summary) was observed after ventral surgery (P = .05). The complication rate (16.6% overall) was comparable between groups. Significant improvement in the modified Japanese Orthopedic Association scale score was observed in both groups (P &lt; .01). Dorsal fusion surgery had significantly greater mean hospital costs ($29 465 vs $19 245; P &lt; .01) and longer average length of hospital stay (4.0 vs 2.6 days; P &lt; .01) compared with ventral fusion surgery.

CONCLUSION:

Surgery for treating CSM was followed by significant improvement in disease-specific symptoms and in HR-QOL. Greater improvement in HR-QOL was observed after ventral surgery. Dorsal fusion surgery was associated with longer length of hospital stay and higher hospital costs. The pilot study demonstrated feasibility for a larger randomized clinical trial.

Preserving the C7 spinous process in laminectomy combined with lateral mass screw to prevent axial symptom

BACKGROUND

Preserving the C7 spinous process during cervical laminoplasty has been reported to prevent axial symptom. Some patients underwent laminectomy and fixation developed the symptom. The objective of this article was to investigate whether axial symptom can be reduced by preserving the C7 spinous process during cervical laminectomy and fixation with lateral mass screw.

METHODS

Between 2005 and 2008, data of 53 patients who underwent laminectomy and lateral mass-screw fixation for multilevel cervical myelopathy were reviewed. Analysis consisted of the incidence of axial symptom, Japan Orthopaedic Association (JOA) scores, recovery rate, cervical lordotic angle, and atrophy rate of cervical posterior muscle. Axial symptom severity was quantified by a visual analog scale (VAS). Twenty-five patients were decompressed from C3 to C7 (group A) and 28 from C3 to C6 with dome-shape removal of the C7 superior lamina (group B).

RESULTS

Analysis of final follow-up data showed improvement in clinical outcome for both groups. No difference in recovery rate, cervical lordotic angle and atrophy rate was observed between groups. Postoperative axial-neck pain was significantly rarer in group B than in group A. Axial symptom severity was correlated with cervical posterior muscle atrophy rate; correlation coefficient was 0.665.

CONCLUSION

The C7 spinous process might play an important role in preventing axial symptom, but there is a need for randomized, control studies with long-term follow-up to clarify the results.

Cervical surgical techniques for the treatment of cervical spondylotic myelopathy

OBJECT

The objective of this systematic review was to use evidence-based medicine to compare the efficacy of different surgical techniques for the treatment of cervical spondylotic myelopathy (CSM).

METHODS

The National Library of Medicine and Cochrane Database were queried using MeSH headings and keywords relevant to anterior and posterior cervical spine surgery and CSM. The guidelines group assembled an evidentiary table summarizing the quality of evidence (Classes I-III). The group formulated recommendations that contained the degree of strength based on the Scottish Intercollegiate Guidelines network. Validation was done through peer review by the Joint Guidelines Committee of the American Association of Neurological Surgeons/Congress of Neurological Surgeons.

RESULTS

A variety of techniques have improved functional outcome after surgical treatment for CSM, including anterior cervical discectomy with fusion (ACDF), anterior cervical corpectomy with fusion (ACCF), laminoplasty, laminectomy, and laminectomy with fusion (Class III). Anterior cervical discectomy with fusion and ACCF appear to yield similar results in multilevel spine decompression for lesions at the disc level. The use of anterior plating allows for equivalent fusion rates between these techniques (Class III). If anterior fixation is not used, ACCF may provide a higher fusion rate than multilevel ACDF but also a higher graft failure rate than multilevel ACDF (Class III). Anterior cervical discectomy with fusion, ACCF, laminectomy, laminoplasty, and laminectomy with arthrodesis all provide near-term functional improvement for CSM. However, laminectomy is associated with late deterioration compared with the other types of anterior and posterior surgeries (Class III).

CONCLUSIONS

Multiple approaches exist with similar near-term improvements; however, laminectomy appears to have a late deterioration rate that may need to be considered when appropriate.

Preoperative patient selection with magnetic resonance imaging, computed tomography, and electroencephalography: does the test predict outcome after cervical surgery?

OBJECT

The objective of this systematic review was to use evidence-based medicine to assess whether preoperative imaging or electromyography (EMG) predicts surgical outcomes in patients undergoing cervical surgery.

METHODS

The National Library of Medicine and Cochrane Database were queried using MeSH headings and keywords relevant to the preoperative imaging and EMG. Abstracts were reviewed after which studies meeting inclusion criteria were selected. The guidelines group assembled an evidentiary table summarizing the quality of evidence (Classes I-III). Disagreements regarding the level of evidence were resolved through an expert consensus conference. The group formulated recommendations that contained the degree of strength based on the Scottish Intercollegiate Guidelines network. Validation was done through peer review by the Joint Guidelines Committee of the American Association of Neurological Surgeons/Congress of Neurological Surgeons.

RESULTS

Preoperative MR imaging and CT myelography are successful in confirming clinical radiculopathy (Class II). Multilevel T2 hyperintensity, T1 focal hypointensity combined with T2 focal hyperintensity, and spinal cord atrophy each convey a poor prognosis (Class III). There is conflicting data concerning whether focal T2 hyperintensity or cervical stenosis are associated with a worse outcome. Electromyography has mixed utility in predicting outcome (Class III).

CONCLUSIONS

Magnetic resonance imaging or CT myelography are important for preoperative assessment. Magnetic resonance imaging may be helpful in assessing prognosis, whereas EMG has mixed utility in assessing outcome.