Anterior cervical corpectomy for cervical spondylotic myelopathy

A novel cervical vertebral bone quality score can independently predict cage subsidence after anterior cervical corpectomy and fusion

OBJECTIVES

To optimize cervical vertebral bone quality (C-VBQ) score and explore its effectiveness in predicting cage subsidence in Anterior Cervical Corpectomy and Fusion (ACCF) and identify a new method for evaluating subsidence without different equipment and image scale interference.

METHODS

Collecting demographic, imaging, and surgical related information. Measuring Cage Subsidence with a new method. Multifactorial logistic regression was used to identify risk factors associated with subsidence. Pearson's correlation was used to determine the relationship between C-VBQ and computed tomography (CT) Hounsfield units (HU). The receiver operating characteristic (ROC) curve was used to assess C-VBQ predictive ability. Correlations between demographics and C-VBQ scores were analyzed using linear regression models.

RESULTS

92 patients were included in this study, 36 (39.1%) showed subsidence with a C-VBQ value of 2.05 ± 0.45, in the no-subsidence group C-VBQ Value was 3.25 ± 0.76. The multifactorial logistic regression showed that C-VBQ is an independent predictor of cage subsidence with a predictive accuracy of 93.4%. Pearson's correlation analysis showed a negative correlation between C-VBQ and HU values. Linear regression analysis showed a positive correlation between C-VBQ and cage subsidence. Univariate analyses showed that only age was associated with C-VBQ.

CONCLUSIONS

The C-VBQ values obtained using the new measurements independently predicted postoperative cage subsidence after ACCF and showed a negative correlation with HU values. By adding the measurement of non-operated vertebral heights as a control standard, the results of cage subsidence measured by the ratio method are likely to be more robust, perhaps can exclude unavoidable errors caused by different equipment and proportional.

Safety of anterior cervical corpectomy and fusion (ACCF) for the treatment of subaxial cervical spine injuries, a single center comparative matched analysis

INTRODUCTION

Anterior Cervical Discectomy and Fusion (ACDF) and Anterior Cervical Corpectomy and Fusion (ACCF) are both common surgical procedures in the management of pathologies of the subaxial cervical spine. While recent reviews have demonstrated ACCF to provide better decompression results compared to ACDF, the procedure has been associated with increased surgical risks. Nonetheless, the use of ACCF in a traumatic context has been poorly described. The aim of this study was to assess the safety of ACCF as compared to the more commonly performed ACDF.

METHODS

All patients undergoing ACCF or ACDF for subaxial cervical spine injuries spanning over 2 disc-spaces and 3 vertebral-levels, between 2006 and 2018, at the study center, were eligible for inclusion. Patients were matched based on age and preoperative ASIA score.

RESULTS

After matching, 60 patients were included in the matched analysis, where 30 underwent ACDF and ACCF, respectively. Vertebral body injury was significantly more common in the ACCF group (p = 0.002), while traumatic disc rupture was more frequent in the ACDF group (p = 0.032). There were no statistically significant differences in the rates of surgical complications, including implant failure, wound infection, dysphagia, CSF leakage between the groups (p ≥ 0.05). The rates of revision surgeries (p > 0.999), mortality (p = 0.222), and long-term ASIA scores (p = 0.081) were also similar.

CONCLUSION

Results of both unmatched and matched analyses indicate that ACCF has comparable outcomes and no additional risks compared to ACDF. It is thus a safe approach and should be considered for patients with extensive anterior column injury.

Characterizing mJOA-defined post-surgical recovery patterns in patients with degenerative cervical myelopathy

Background

Degenerative cervical myelopathy is a spinal disorder resulting in progressive cord compression and neurological deficits that are assessed using the modified Japanese Orthopedic Association (mJOA) questionnaire. It is difficult to predict which patients will recover neurological function after surgery, making it challenging for clinicians to set postoperative patient expectations. In this study, we used mJOA subscores to identify patterns of recovery and recovery timelines in patients with moderate and severe myelopathy.

Methods

Fifty-three myelopathy patients were enrolled and completed the mJOA questionnaire both pre-surgery, and six weeks and six months post-surgery. Pearson chi-square tests were performed to assess relationships of both recovery patterns and recovery timelines with severity of disease.

Results

Moderate myelopathy patients were significantly more likely than severe myelopathy patients to experience full recovery of upper extremity, lower extremity, and sensory domains. Disease severity did not significantly impact the timeline during which recovery occurs. Overall, >90% of patients experienced at least partial recovery by six months post surgery, 80% of which demonstrated it within the first six weeks.

Conclusions

This study shows the more severe the disease experienced by myelopathy patients, the more likely they will be left with permanent disabilities despite surgery. Early identification and treatment are therefore necessary to prevent worsening quality of life and increased costs of functional dependence. The recovery timelines for each subscore are similar and provide new values to guide patient expectations in their potential post-operative recovery. The overall recovery timeline is more generalizable though potentially lacking the specificity patients seek.

Anterior cervical corpectomy for the treatment of spondylotic myelopathy: results of a prospective double-armed study with a three-year follow-up

BACKGROUND

Since the first description in the 1950s, cervical spondylotic myelopathy (CSM) has posed many challenges to neurosurgeons and spine surgeons. Direct comparison among different operative approaches has failed to produce valuable results due to either an insufficient number of enrolled patients or a lack of standardization of baseline conditions. This prospective double-armed non-randomized study with a 3-year follow-up involved 80 patients with degenerative cervical myelopathy surgically and conservatively treated. The primary aim was to determine the efficacy of corpectomy in mild-moderate and severe CSM and to compare the outcomes of conservative and surgical treatment.

METHODS

Eighty patients were stratified into two arms, on the basis of the mJOA score: mild-moderate (mJOA ≥12) and severe myelopathy (mJOA score <12). Each arm was subdivided into two treatment groups (operative or conservative): A1, mild-moderate myelopathy treated with corpectomy; A2, mild-moderate myelopathy treated conservatively; B1, severe myelopathy treated with corpectomy; B2, severe cervical myelopathy treated conservatively. The clinical outcome was evaluated with the modified JOA score, timed 10-meter walk, Mehalic grade, motor evoked potentials, the SF-12, and further assessed by external observers blinded to the type of treatment.

RESULTS

No significant differences in the recovery rates were found between the A1 and A2 groups at 6 months, although better results were recorded in the surgical groups (A1 and B1) at 12 months and at the final follow-up, as suggested by the significantly higher recovery rates. Multivariate analysis showed an inverse correlation between the duration of symptoms and the recovery rate (P<0.0001). Moreover, the preoperative timed 10-meter walk (P<0.004), the preoperative hypointensity on T1-weighted MR images (P<0.001), a higher Mehalic grade (P<0.02), the pre-treatment MEP (P<0.002), and the preoperative spinal canal diameter (P<0.004) significantly influenced the recovery rate.

CONCLUSIONS

This prospective double-armed non-randomized study demonstrates that corpectomy is an effective and safe treatment, especially for severe forms of myelopathy. In mild-moderate conditions, a discrepancy between neurological improvement and expressed level of satisfaction was found. The present results also show that a multiparametric evaluation is crucial for proper patient selection for corpectomy.

One Hundred Top Cited Articles in Cervical Myelopathy: A Bibliographic Analysis

STUDY DESIGN

A bibliometric review of the literature.

OBJECTIVES

The aim of this study was to identify the most highly cited articles relating to cervical myelopathy and to analyze the most influential articles.

SUMMARY OF BACKGROUND DATA

Over the past several decades, a lot of research has been conducted regarding the subject of cervical myelopathy. Although there are a large number of articles on this topic, to our knowledge, this is the first bibliometric analysis.

METHODS

A selection of search terms and keywords were inputted into the "Dimensions" database and the most highly cited articles in cervical myelopathy were selected from high impact factor journals. The top 100 articles were analyzed for year of publication, authorship, publishing journals, institution and country of origin, subject matter, article type, and level of evidence.

RESULTS

The 100 most cited articles in the topic of cervical myelopathy were published from 1956 to 2015. These articles, their corresponding authors, and number of citations are shown in Table 1. The number of citations ranged from 121 times for the 100th article to 541 times for the top article in a total of 20 journals. The most common topic was operative technique, whereas the journals which contributed the most articles were the Spine journal and the Journal of Neurosurgery.

CONCLUSION

Our study provided an extensive list of the most historically significant articles regarding cervical myelopathy, acknowledging the key contributions made to the advancement of this field.Level of Evidence: 5.

Risk Factors and Radiologic Changes in Subsidence after Single-Level Anterior Cervical Corpectomy: A Minimum Follow-Up of 2 Years

Objective

Anterior cervical corpectomy using a titanium mesh cage may result in delayed nonunion and thus a change in cervical alignment, and patients may require revision surgery. We investigated the radiologic and clinical outcomes of cervical corpectomy and the risk factors for subsidence.

Methods

We studied 74 patients who underwent single-level anterior cervical corpectomy for cervical spondylotic myelopathy with or without ossification of the posterior longitudinal ligament between 2007 and 2014. Graft subsidence was considered present when there was a reduction in the anterior and posterior heights by an average of 4 mm or more 2 years after the operation. We measured cervical parameters before surgery, immediately after surgery, and 6, 12, and 24 months after surgery. The clinical outcomes were the neck and arm visual analog scale scores and reoperation rate.

Results

In the subsidence group, these values gradually decreased over the 24 months. The radiologic parameters did not differ between the 2 groups for 24 months after the onset of subsidence. There were no differences in clinical outcome or reoperation rate. In the analysis of the risk factors, subsidence occurred with a large T1 slope and a large change in the C27 Cobb angle (p=0.020 and p=0.026, respectively).

Conclusion

Subsidence gradually occurred after single-level anterior cervical corpectomy for up to 24 months. However, the presence of subsidence did not affect the radiologic and clinical outcomes. When the T1 slope was large and the C27 Cobb angle change was severe, more subsidence occurred.

Spinal cord compression is associated with brain plasticity in degenerative cervical myelopathy

The impact of spinal cord compression severity on brain plasticity and prognostic determinates is not yet fully understood. We investigated the association between the severity of spinal cord compression in patients with degenerative cervical myelopathy, a progressive disease of the spine, and functional plasticity in the motor cortex and subcortical areas using functional magnetic resonance imaging. A 3.0 T MRI scanner was used to acquire functional images of the brain in 23 degenerative cervical myelopathy patients. Patients were instructed to perform a structured finger-tapping task to activate the motor cortex to assess the extent of cortical activation. T₂-weighted images of the brain and spine were also acquired to quantify the severity of spinal cord compression. The observed blood oxygen level-dependent signal increase in the contralateral primary motor cortex was associated with spinal cord compression severity when patients tapped with their left hand (r = 0.49, P = 0.02) and right hand (r = 0.56, P = 0.005). The volume of activation in the contralateral primary motor cortex also increased with spinal cord compression severity when patients tapped with their left hand (r = 0.55, P = 0.006) and right hand (r = 0.45, P = 0.03). The subcortical areas (cerebellum, putamen, caudate and thalamus) also demonstrated a significant relationship with compression severity. It was concluded that degenerative cervical myelopathy patients with severe spinal cord compression recruit larger regions of the motor cortex to perform finger-tapping tasks, which suggests that this adaptation is a compensatory response to neurological injury and tissue damage in the spinal cord.

Establishment of a nomogram for predicting the surgical difficulty of anterior cervical spine surgery

Background

For a long time, surgical difficulty is mainly evaluated based on subjective perception rather than objective indexes. Moreover, the lack of systematic research regarding the evaluation of surgical difficulty potentially has a negative effect in this field. This study was aimed to evaluate the risk factors for the surgical difficulty of anterior cervical spine surgery (ACSS).

Methods

This was a retrospective cohort study totaling 291 consecutive patients underwent ACSS from 2012.3 to 2017.8. The surgical difficulty of ACSS was defined by operation time longer than 120 min or intraoperative blood loss equal to or greater than 200 ml. Evaluation of risk factors was performed by analyzing the patient’s medical records and radiological parameters such as age, sex, BMI, number of operation levels, high signal intensity of spinal cord on T2-weighted images, ossified posterior longitudinal ligament (OPLL), sagittal and coronal cervical circumference, cervical length, spinal canal occupational ratio, coagulation function index and platelet count.

Results

Significant differences were reported between low-difficulty and high-difficulty ACSS groups in terms of age (p = 0.017), sex (p = 0.006), number of operation levels (p < 0.001), high signal intensity (p < 0.001), OPLL (p < 0.001) and spinal canal occupational ratio (p < 0.001). Multivariate logistic regression analysis revealed that number of operation levels (OR = 5.224, 95%CI = 2.125–12.843, p < 0.001), high signal intensity of spinal cord (OR = 4.994, 95%CI = 1.636–15.245, p = 0.005), OPLL (OR = 6.358, 95%CI = 1.932–20.931, p = 0.002) and the spinal canal occupational ratio > 0.45 (OR = 3.988, 95%CI = 1.343–11.840, p = 0.013) were independently associated with surgical difficulty in ACSS. A nomogram was established and ROC curve gave a 0.906 C-index. There was a good calibration curve for difficulty estimation.

Conclusion

This study indicated that the operational level, OPLL, high signal intensity of spinal cord, and spinal canal occupational ratio were independently associated with surgical difficulty and a predictive nomogram can be established using the identified risk factors. Optimal performance was achieved for predicting surgical difficulty of ACSS based on preoperative factors.

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.

Cervical Spondylotic Myelopathy: When and Why the Cervical Corpectomy?

BACKGROUND

Cervical spondylotic myelopathy (CSM) is a degenerative disease that represents the most common spinal cord disorder in adults. The best treatment option has remained controversial. We performed a prospective study to evaluate the clinical, radiographic, and neurophysiologic outcomes for anterior cervical corpectomy in the treatment of CSM.

METHODS

From January 2011 to January 2017, 60 patients with CSM were prospectively enrolled in the present study. The patients were divided according to the modified Japanese Orthopaedic Association scale (mJOA) score into 2 groups: group A, patients with mild to moderate CSM (mJOA score ≥13); and group B, patients with severe myelopathy (mJOA score <13). Data were collected for each participating subject, including demographic information, symptoms, medical history, radiologic and neurophysiologic features, and functional impairment.

RESULTS

Of the 60 patients, 35 were men (58.3%) and 25 were women (41.7%). Their average age was 57.48 ± 10.60 years. The mean symptom duration was 25.33 ± 16.00 months; range, 3-57 months). Of the 60 patients, 22 had undergone single-level corpectomy and 36 multilevel corpectomy. A significant improvement in the motor evoked potentials was observed in both groups.

CONCLUSIONS

Single- and multilevel corpectomy are valid and safe options in the treatment of CSM. In the present prospective study, a statistically significant improvement in the mJOA score and neurophysiologic parameters was observed for both moderate and severe forms of CSM.

Complications of anterior cervical spine surgery: a systematic review of the literature

The anterior approach to the cervical spine is commonly utilized for a variety of degenerative, traumatic, neoplastic, and infectious indications. While many potential complications overlap with those of the posterior approach, the distinct anatomy of the anterior neck also presents a unique set of hazards. We performed a systematic review of the literature to assess the etiology, presentation, natural history, and management of these complications. Following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), a PubMed search was conducted to evaluate clinical studies and case reports of patients who suffered a complication of anterior cervical spine surgery. The search specifically included articles concerning adult human subjects, written in the English language, and published from 1989 to 2019. The PubMed search yielded 240 articles meeting our criteria. The overall rates of complications were as follows: dysphagia 5.3%, esophageal perforation 0.2%, recurrent laryngeal nerve palsy 1.3%, infection 1.2%, adjacent segment disease 8.1%, pseudarthrosis 2.0%, graft or hardware failure 2.1%, cerebrospinal fluid leak 0.5%, hematoma 1.0%, Horner syndrome 0.4%, C5 palsy 3.0%, vertebral artery injury 0.4%, and new or worsening neurological deficit 0.5%. Morbidity rates in anterior cervical spine surgery are low. Nevertheless, the unique anatomy of the anterior neck presents a wide variety of potential complications involving vascular, aerodigestive, neural, and osseous structures.

Risk factors for subsidence of titanium mesh cage following single-level anterior cervical corpectomy and fusion

Background

To clarify the risk factors for subsidence of titanium mesh cage (TMC) following single-level anterior cervical corpectomy and fusion (ACCF) to reduce subsidence.

Methods

The present retrospective cohort study included 73 consecutive patients who underwent single-level ACCF. Patients were divided into subsidence (n = 31) and non-subsidence groups (n = 42). Medical records and radiological parameters such as age, sex, operation level, segmental angle (SA), cervical sagittal angle (CSA), height of anterior (HAE) and posterior endplate (HPE), ratio of anterior (RAE) and posterior endplate (RPE), the alignment of TMC, the global cervical Hounsfield Units (HU) were analyzed. Clinical results were evaluated using the Japanese Orthopedic Association (JOA) scoring system and the Visual Analog Scale (VAS).

Results

Subsidence occurred in 31 of 73 (42.5%) patients. Comparison between the groups showed significant differences in the value of RAE, the alignment of TMC and the global cervical HU value (p < 0.001, p = 0.002, p < 0.001). In multivariate logistic regression analysis, RAE > 1.18 (OR = 6.116, 95%CI = 1.613–23.192, p = 0.008), alignment of TMC > 3° (OR = 5.355, 95%CI = 1.474–19.454, p = 0.011) and the global cervical HU value< 333 (OR = 11.238, 95%CI = 2.844–44.413, p = 0.001) were independently associated with subsidence. Linear regression analysis revealed that RAE is significantly positive related to the extent of subsidence (r = − 0.502, p = 0.006).

Conclusion

Our findings suggest that the value of RAE more than 1.18, alignment of TMC and poor bone mineral density are the risk factors for subsidence. TMC subsidence does not negatively affect the clinical outcomes after operation. Avoiding over expansion of intervertebral height, optimizing placing of TMC and initiation of anti-osteoporosis treatments 6 months prior to surgery might help surgeons to reduce subsidence after ACCF.

A Systematic Review of Definitions for Neurological Complications and Disease Progression in Patients Treated Surgically for Degenerative Cervical Myelopathy

STUDY DESIGN

Systematic review.

OBJECTIVE

This review aims to (1) outline how neurological complications and disease progression are defined in the literature and (2) evaluate the quality of definitions using a novel four-point rating system.

SUMMARY OF BACKGROUND DATA

Degenerative cervical myelopathy (DCM) is a progressive, degenerative spine disease that is often treated surgically. Although uncommon, surgical decompression can be associated with neurological complications, such as C5 nerve root palsy, perioperative worsening of myelopathy, and longer-term deterioration. Unfortunately, important questions surrounding these complications cannot be fully addressed due to the heterogeneity in definitions used across studies. Given this variability, there is a pressing need to develop guidelines for the reporting of surgical complications in order to accurately evaluate the safety of surgical procedures.

METHODS

An electronic database search was conducted in MEDLINE, MEDLINE in Process, EMBASE and Cochrane Central Register of Controlled Trials for studies that reported on complications related to DCM surgery and included at least 10 surgically treated patients. Data extracted included study design, surgical details, as well as definitions and rates of surgical complications. A four-point rating scale was developed to assess definition quality for each complication.

RESULTS

Our search yielded 2673 unique citations, 42 of which met eligibility criteria and were summarized in this review. Defined complications included neurological deterioration, late onset deterioration, perioperative worsening of myelopathy, C5 palsy, nerve root or upper limb palsy or radiculopathy, surgery failure, inadequate decompression and progression of ossified lesions. Reported rates of these complications varied substantially, especially those for neurological deterioration (0.2%-33.3%) and progression of ossified lesions (0.0%-86.7%).

CONCLUSION

Reported incidences of various complications vary widely in DCM surgery, especially for neurological deterioration and progression of ossified lesions. This summary serves as a first step for standardizing definitions and developing guidelines for accurately reporting surgical complications.

LEVEL OF EVIDENCE

2.

Role of Decompressive Laminectomy without Instrumentation in the Management of Nurick Grade 4 and 5 Cervical Compressive Myelopathy

Introduction

Cervical laminectomy is a very well-known posterior decompressive procedure for cervical compressive myelopathy (CCM). Our objective is to evaluate the functional effect of posterior decompressive laminectomy for poor grade CCM.

Methods

This study was an observational retrospective study carried out on patients with poor-grade CCM who underwent decompressive laminectomy from January 2010 to December 2015. Patients with Nurick Grades 4 and 5 (walking with support or bedbound) were included in the study. Clinical data and radiological information were collected from medical records, and objective scales were applied to compare the surgical outcome between preoperative score and postoperative score.

Results

A total of 69 patients who underwent decompressive laminectomy for poor grade CCM were included. The mean age was 54.9 years, and the male-to-female ratio was 5.3:1. Ossified posterior longitudinal ligament comprised 52.6% cases. The follow-up data of at least 6 months' duration after surgery was available for 57 (82.6%) cases. On comparing with preoperative Nurick grade at follow-up, 40 of the 57 patients (70.2%) were found to have improvement following surgery by at least one grade. The remaining 17 (29.8%) had either remained the same or had deteriorated further. The mean preoperative modified Japanese Orthopedic Association score was 8.4 ± 2.8, and the mean follow-up score was 11.8±0.3 (P = 0.0001). On multivariate analysis, the number of levels of laminectomy, postoperative deterioration, and anesthesia grade were predictors of outcome.

Conclusion

Decompressive laminectomy for poor grade myelopathy is effective in improving functional outcome.

Evaluation of five scoring systems for cervical spondylogenic myelopathy

BACKGROUND CONTEXT

Comparison of measured clinical deficits and outcomes is vital for international discussion about the identification and treatment of cervical spondylotic myelopathy (CSM). There is currently little information comparing outcomes as assessed by different CSM scoring systems.

PURPOSE

To qualitatively and quantitatively analyze five specific CSM outcome scores that are frequently used to assess the grade of severity and outcome after operative decompression.

STUDY DESIGN

This retrospective study evaluated the Nurick score, the Japanese Orthopedic Association score (JOA score), the Cooper myelopathy scale (CMS), the Prolo score, and the European myelopathy score (EMS).

PATIENT SAMPLE

The study included 43 patients with clinical and morphological signs of CSM, who underwent ventral decompression. Data were evaluated in sufficient detail to objectively assess the scores.

OUTCOME MEASURES

Clinical findings (funicular and radicular symptoms), recovery rate, symptom duration, age, economic situation, time away from employment, somatic-evoked potentials, and radiological findings were assessed.

METHODS

Scores were assessed using both pre- and postoperative clinical data. Correlations between scores, score improvement, and how well the scores reflected the clinical, diagnostic, and anamnestic data were analyzed using nonparametric, descriptive statistical tests. The recovery rate, as a measure of cumulative outcome, was also assessed and compared for each scoring system.

RESULTS

All five scores were suitable for qualitatively assessing the clinical characteristics and progression of cervical myelopathy. All showed a statistically significant correlation (p<.05), and measured postoperative improvement (p<.001). All scores also reflected clinical deficits except for the Prolo score, which rates the severity of CSM with an emphasis on data related to the economic impact on the patient's situation rather than on clinical symptoms per se. Quantitative assessment of clinical symptom improvement varied greatly among the scores, for example, Nurick score (33%) versus JOA score (81%). The recovery rates, as a measure of cumulative improvement, showed less variation among most of the scores. The Nurick score and the EMS measured clinical deficit improvements in significantly fewer patients than did the JOA score (p<.05).

CONCLUSIONS

Evaluating the recovery rate is essential for comparing the results of the five CSM scores evaluated in this study. There was a large quantitative difference among the scores as the result of the different criteria used to produce each score. Qualitatively, all five scores allowed evaluation of cervical myelopathy, but only the recovery rate allowed for statistical comparison. Advancements in the treatment of CSM depend on the ability of clinicians to evaluate the therapeutic results of CSM studies. This study suggests that using the recovery rate to assess outcome is best for comparing studies that use different scores.

Ultrasonic bone scalpel: utility in cervical corpectomy. A technical note

PURPOSE

Anterior cervical corpectomy and fusion (ACCF) is a technically challenging surgery. Use of conventional instruments like high-speed burr and kerrison rongeurs is associated with high complication rates such as increased blood loss and incidental durotomy. Use of ultrasonic bone scalpel (UBS) in cervical corpectomy helps to minimize such adverse events.

METHODS

We performed a retrospective study based on the data of 101 consecutive patients who underwent cervical corpectomies with UBS for different cervical spine pathologies from December 2014 to December 2016. Total duration of surgery, time taken for corpectomy, estimated blood loss, and incidental durotomies were noted.

RESULTS

Total surgical time was 30-80 min (59.36 ± 13.21 min) for single-level ACCF and 60-120 min (92.74 ± 21.04 min) for double-level ACCF. Time taken for single-level corpectomy was 2 min 11  ± 10 s and 3 min 41  ± 20 s for double-level corpectomy. Estimated blood loss ranged from 20-150 ml (52.07 ± 29.86 ml) in single level and 40-200 ml (73.22 ± 41.64 ml) in double level. Four (3.96%) inadvertent dural tears were noted, two during single-level corpectomy and other two during double-level corpectomy.

CONCLUSIONS

Use of UBS is likely to provide a safe, rapid, and effective surgery when compared to conventional rongeurs and high-speed burr. The advantages such as lower blood loss and lower intra-operative incidental dural tears were noted with the use of UBS.

Neurological Recovery Pattern in Cervical Spondylotic Myelopathy after Anterior Surgery: A Prospective Study with Literature Review

Study Design

Prospective clinical study.

Purpose

The present study aimed to examine the neurological recovery pattern in cervical spondylotic myelopathy (CSM) after anterior cervical decompression and compare it with the existing reports in the literature.

Overview of Literature

Neurological recovery and regression of myelopathy symptoms is an important factor that determines the outcomes of surgical decompression. The present findings contribute to the literature on the pattern of neurological recovery and patient prognosis with respect to the resolution of myelopathy symptoms after surgery.

Methods

This prospective study was conducted in Government Medical College in Jammu, North India between November 2012 and October 2014, a total of 30 consecutive patients with CSM were included and treated with anterior decompression and stabilization. They were prospectively followed up for 1 year and were evaluated for their neurological recovery pattern. The postoperative outcome was evaluated using the modified Japanese Orthopaedic Association (mJOA) score. The recovery rate was calculated using Hirabayashi’s method. The JOA score was assessed before the operation and postoperatively at 1 week, 2 weeks, 1 month, 3 months, 4 months, 6 months, and 1 year.

Results

The postoperative mJOA score was 0 in the 1st month, 12.90±3.57 in the 3rd month, 13.50±3.55 in the 4th month, 14.63±3.62 in the 6th month, and 14.9±3.24 at the final follow-up of 1 year. The average recovery rate during the 1st month follow-up was 0%, and that during the 3rd month follow-up was 12.91% with a range of 0%–50%. The average recovery rate during the 4th month was 32.5%, with a range of 0%–60%, while that during the 6th month was 72.83%, with a range of 0%–100%. The average recovery rate during the final follow-up of 1 year was 54.3%.

Conclusions

Neurological recovery after surgical decompression starts from the 3rd postoperative month and progresses until the 6th postoperative month; thereafter, it gradually plateaus over the subsequent 6 months until it steadies. Symptom duration is an important factor that requires consideration while determining postoperative neurological recovery.

Clinical Comparison of Surgical Constructs for Anterior Cervical Corpectomy and Fusion in Patients With Cervical Spondylotic Myelopathy or Ossified Posterior Longitudinal Ligament: A Systematic Review and Meta-Analysis

STUDY DESIGN

This is a systematic review and meta-analysis.

OBJECTIVE

To examine the differences in outcomes among current constructs and techniques for anterior cervical corpectomy and fusion (ACCF) in patients with single or multiple level cervical myelopathy (CM) secondary to cervical spondylosis or ossified posterior longitudinal ligament.

SUMMARY OF BACKGROUND DATA

The natural history of CM can be a progressive disease process. In such cases, where surgical decompression is indicated to halt the progression, ACCF is typically chosen for pathology located posterior to the vertebral body. Numerous studies have shown that decompression with appropriate stabilization not only halts progression, but also improves patient outcomes. However, several constructs are available for this procedure, all with variable outcomes.

MATERIALS AND METHODS

A systematic review was conducted using Cochrane Database, Medline, and PubMed. Only studies with a minimum patient population of 10, reporting on CM because of cervical spondylosis or ossified posterior longitudinal ligament were included; a minimum follow-up period of 12 months and 1 clinical and/or radiographic outcome were required. Studies examining patients with cervical trauma/fracture, tumor, and infection or revision cases were excluded. Data analysis was carried out with Microsoft Excel.

RESULTS

A total of 30 studies met the inclusion criteria for qualitative analysis, while 26 studies were included for quantitative analysis. Constructs that were reported in these studies included titanium mesh cages, nano-hydroxyapatite/polyamide 66 composite struts, bone graft alone, expandable corpectomy cages, and polyetheretherketone cages. Clinical outcomes included Japanese Orthopaedic Association and modified Japanese Orthopaedic Association scores, Visual Analog Scale scores, Neck Disability Index scores, and Nurick grades. Radiographic outcomes included C2-C7 and segmental Cobb angles and pseudarthrosis rates. Each construct type had variable and unique benefits and shortcomings.

CONCLUSIONS

ACCF is a common surgical option for CM, despite carrying certain risks expected of any anterior cervical approach. Several constructs are available for ACCF, all with variable clinical and radiographic outcomes.

Two-level cervical corpectomy-long-term follow-up reveals the high rate of material failure in patients, who received an anterior approach only

In contrast to a one-level cervical corpectomy, a multilevel corpectomy without posterior fusion is accompanied by a high material failure rate. So far, the adequate surgical technique for patients, who receive a two-level corpectomy, remains to be elucidated. The aim of this study was to determine the long-term clinical outcome of patients with cervical myelopathy, who underwent a two-level corpectomy. Outcome parameters of 21 patients, who received a two-level cervical corpectomy, were retrospectively analyzed concerning reoperations and outcome scores (VAS, Neck Disability Index (NDI), Nurick scale, modified Japanese Orthopaedic Association score (mJOAS), Short Form 36-item Health Survey Questionnaire (SF-36)). The failure rate was determined using postoperative radiographs. The choice over the surgical procedures was exercised by every surgeon individually. Therefore, a distinction between two groups was possible: (1) anterior group (ANT group) with a two-level corpectomy and a cervical plate, (2) anterior/posterior group (A/P group) with two-level corpectomy, cervical plate, and additional posterior fusion. Both groups benefitted from surgery concerning pain, disability, and myelopathy. While all patients of the A/P group showed no postoperative instability, one third of the patients of the ANT group exhibited instability and clinical deterioration. Thus, a revision surgery with secondary posterior fusion was needed. Furthermore, the ANT group had worse myelopathy scores (mJOAS_{ANT group} = 13.5 ± 2.5, mJOAS_{A/P group} = 15.7 ± 2.2). Patients with myelopathy, who receive a two-level cervical corpectomy, benefitted from surgical decompression. However, patients with a sole anterior approach demonstrated a very high rate of instability (33%) and clinical deterioration in a long-term follow-up. Therefore, we recommend to routinely perform an additional posterior fusion after two-level cervical corpectomy.

Long-Term Sustainability of Functional Improvement Following Central Corpectomy for Cervical Spondylotic Myelopathy and Ossification of Posterior Longitudinal Ligament

STUDY DESIGN

Retrospective study.

OBJECTIVE

To examine predictors of long-term outcome and sustainability of initial functional improvement in patients undergoing corpectomy for cervical spondylotic myelopathy (CSM) or ossification of the posterior longitudinal ligament (OPLL).

SUMMARY OF BACKGROUND DATA

There are limited data on the predictors of outcome and sustainability of initial functional improvement on long-term follow-up after cervical corpectomy.

METHODS

We studied the functional outcome at more than 1-year follow-up after central corpectomy in 352 patients with CSM or OPLL. Functional status was evaluated with the Nurick grading system. Analysis was directed at identifying factors associated with both improvement in functional status and the achievement of a "cure" (improvement to a follow-up Nurick grade of 0 or 1). A survival analysis was performed to identify factors associated with sustained functional improvement in patients with serial follow-up evaluations.

RESULTS

Nurick grade improved from 3.2 ± 0.1 to 1.9 ± 0.1 over a mean follow-up period of 57.1 months (range 12-228 mo). On multivariate analysis, age ≥50 years (P = 0.008) and symptom duration ≥1 year (P < 0.001) were negatively associated with functional improvement by ≥1 Nurick grade. Independent factors negatively associated with "cure" after surgery included age 50 years or older (P = 0.005), preoperative Nurick grade of 4 or higher (P < 0.001) and symptom duration of 1 or more years (P < 0.001). Early improvement in functional status was maintained in 90.5% and 76.3% of patients at 5 and 10 years follow-up, respectively. On survival analysis, patients with shorter preoperative symptom duration (<1 yr) were more likely to demonstrate sustained improvement in functional status after surgery (P = 0.022).

CONCLUSION

Initial gains in functional status after central corpectomy for CSM and OPLL are maintained in more than 75% of patients at 10 years after surgery. Overall, the most favorable long-term outcomes are achieved in younger patients who present early and with good preoperative functional status.

LEVEL OF EVIDENCE

4.

Anterior corpectomy and reconstruction using dynamic cervical plate and titanium mesh cage for cervical spondylotic myelopathy: A minimum 5-year follow-up study

Anterior cervical corpectomy and fusion (ACCF) is an effective surgical technique for cervical spondylotic myelopathy (CSM). However, no data exist regarding long-term outcomes after ACCF with the dynamic cervical plate for CSM. This study aimed to provide minimum 5-year clinical and radiographic outcomes of anterior corpectomy and reconstruction using dynamic cervical plate and titanium mesh cage (TMC) for CSM.Thirty-five patients who underwent single- or 2-level ACCF with dynamic cervical plate and TMC for the treatment of CSM were retrospectively investigated. The Japanese Orthopedic Association (JOA) score was used to assess the clinical outcome. Radiographic evaluations included TMC subsidence, fusion status, cervical lordosis, segmental angle, and segmental height.Twenty-eight patients underwent single-level and 7 patients underwent 2-level corpectomy with a mean follow-up period of 69.5 months. The average preoperative JOA score was 11.3 ± 3.0 and improved significantly to 14.2 ± 2.0 at the last follow-up (P < .001). Both cervical lordosis (P = .013) and segmental angle (P = .001) were significantly increased toward lordosis at the last follow-up. The TMC subsidence rate was 31.4% (n = 11) at the last follow-up. There was no significant difference in JOA recovery rate between subsidence and no subsidence group (P = .43). All patients obtained solid fusion at 1-year follow-up.Anterior corpectomy and reconstruction with dynamic cervical plate and TMC might be an effective method for the treatment of CSM at a minimum 5-year follow-up. It can maintain or restore cervical sagittal alignment. Subsidence of the TMC did not influence the clinical outcome.

Sagittal Alignment of a Strut Graft Affects Graft Subsidence and Clinical Outcomes of Anterior Cervical Corpectomy and Fusion

Study Design

Retrospective study.

Purpose

The purpose of this study was to investigate the influence of sagittal alignment of the strut graft on graft subsidence and clinical outcomes after anterior cervical corpectomy and fusion (ACCF).

Overview of Literature

ACCF is a common technique for the treatment of various cervical pathologies. Although graft subsidence sometimes occurs after ACCF, it is one cause for poor clinical results. Malalignment of the strut graft is probably one of the factors associated with graft subsidence. However, to the best of our knowledge, no prior reports have demonstrated correlations between the alignment of the strut graft and clinical outcomes.

Methods

We evaluated 56 patients (33 men and 23 women; mean age, 59 years; range, 33–84 years; 45 with cervical spondylotic myelopathy and 11 with ossification of the posterior longitudinal ligament) who underwent one- or two-level ACCF with an autogenous fibular strut graft and anterior plating. The Japanese Orthopaedic Association (JOA) score recovery ratio for cervical spondylotic myelopathy was used to evaluate clinical outcomes. The JOA score and lateral radiograms were evaluated 1 week and 1 year postoperatively. Patients were divided into two groups (a straight group [group I] and an oblique group [group Z]) based on radiographic assessment of the sagittal alignment of the strut graft.

Results

Group I showed a significantly greater JOA score recovery ratio (p<0.05) and a significantly lower graft subsidence than group Z (p<0.01).

Conclusions

Our findings suggest that a straight alignment of the strut graft provides better clinical outcomes and lower incidence of graft subsidence after ACCF. In contrast, an oblique strut graft can lead to significantly increased strut graft subsidence and poor clinical results.

Biomechanics of Cervical "Skip" Corpectomy Versus Standard Multilevel Corpectomy

STUDY DESIGN

In vitro biomechanical study of flexibility with finite-element simulation to estimate screw stresses.

OBJECTIVE

To compare cervical spinal stability after a standard plated 3-level corpectomy with stability after a plated 3-level "skip" corpectomy where the middle vertebra is left intact (ie, two 1-level corpectomies), and to quantify pullout forces acting on the screws during various loading modes.

SUMMARY OF BACKGROUND DATA

Clinically, 3-level cervical plated corpectomy has a high rate of failure, partially because only 4 contact points affix the plate to the upper and lower intact vertebrae. Leaving the intermediate vertebral body intact for additional fixation points may overcome this problem while still allowing dural sac decompression.

METHODS

Quasistatic nonconstraining torque (maximum 1 N m) induced flexion, extension, lateral bending, and axial rotation while angular motion was recorded stereophotogrammetrically. Specimens were tested intact and after corpectomy with standard plated and strut-grafted 3-level corpectomy (7 specimens) or "skip" corpectomy (7 specimens). Screw stresses were quantified using a validated finite-element model of C3-C7 mimicking experimentally tested groups. Skip corpectomy with C5 screws omitted was also simulated.

RESULTS

Plated skip corpectomy tended to be more stable than plated standard corpectomy, but the difference was not significant. Compared with standard plated corpectomy, plated skip corpectomy reduced peak screw pullout force during axial rotation (mode of loading of highest peak force) by 15% (4-screw attachment) and 19% (6-screw attachment).

CONCLUSIONS

Skip corpectomy is a good alternative to standard 3-level corpectomy to improve stability, especially during lateral bending. Under pure moment loading, the screws of a cervical multilevel plate experience the highest pullout forces during axial rotation. Thus, limiting this movement in patients undergoing plated multilevel corpectomy may be reasonable, especially until solid fusion is achieved.

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.

Enlarged anterior cervical diskectomy and fusion in the treatment of severe localised ossification of the posterior longitudinal ligament

Background

Severe localised ossification of the posterior longitudinal ligament (OPLL) should be directly removed by anterior approach, but the exposure during anterior cervical diskectomy and fusion (ACDF) is restricted and may increase the risk of a cerebrospinal fluid (CSF) leak. Corpectomy is facilitated to extirpate the ossification, but it is relatively more invasive. The purpose of this study was to investigate the feasibility and clinical outcome of enlarged ACDF in treating severe localised OPLL.

Methods

Twenty-four selective patients with severe localised OPLL who underwent enlarged ACDF from January 2011 to July 2013 were retrospectively investigated. The Japanese Orthopaedic Association (JOA) scales, visual analogue scale (VAS), occupying rate (OR), fused segment height (FSH), sagittal segmental alignment (SSA), range of motion (ROM), and complications were investigated.

Results

After a mean 34.9-month follow-up, the mean JOA score increased from 9.5 ± 1.4 preoperatively to 14.1 ± 1.5 at the final follow-up (p < 0.05), while OR decreased from 58.9 ± 6.1 % pre- to 10.6 ± 5.5 % postoperatively (p < 0.05). The average VAS was 6.1 ± 1.8 preoperatively and 2.1 ± 1.4 at the final follow-up (p < 0.05). The SSA angles at the final follow-up increased 2.2° compared to the preoperative values (p < 0.05). The mean FSH increased 2.4 mm from pre- to postoperatively, but decreased 2.7 mm from postoperatively to final follow-up. The cervical ROM was not obviously reduced at the final follow-up (p > 0.05) because only one level was fixed. There were three cases of cerebrospinal fluid leakage, one case of haematoma, and one case showed transient neurological deterioration.

Conclusions

Enlarged ACDF is an effective procedure for treating selective patients with severe localised OPLL. Using this technique, the retrovertebral OPLL can be removed through a one-level diskectomy and a corpectomy can be avoided.

Trial registration

This study has been registered with the ResearchRegistry and the unique identifying number is researchregistry1365 (K2015-022-04). It was retrospectively registered at 21 June 2016 and the first participant to the trial was at 4 January 2011.

Electronic supplementary material

The online version of this article (doi:10.1186/s13018-016-0449-z) contains supplementary material, which is available to authorized users.

Excision of the Posterior Longitudinal Ligament During Anterior Cervical Corpectomy: A Biomechanical Study

STUDY DESIGN

An in vitro biomechanical study of the cervical spine.

OBJECTIVE

To evaluate the biomechanical significance of the posterior longitudinal ligament (PLL) after anterior cervical corpectomy and reconstruction with a strut graft and anterior plate.

SUMMARY OF BACKGROUND DATA

Routine excision of the PLL during anterior cervical corpectomy is controversial. Many surgeons believe that maintaining the PLL after cervical corpectomy adds stability to the reconstruction, whereas others believe it can be excised without sequelae. There are no biomechanical studies to our knowledge evaluating the biomechanical significance of excising the PLL during corpectomy and whether this affects the stability of a reconstruction consisting of a strut graft and anterior plate. The purpose of this study was to evaluate the biomechanical effects of PLL excision during a complete anterior cervical corpectomy reconstructed with a strut graft and anterior plate.

METHODS

Seven human cadaveric fresh-frozen cervical spines C2-T1 were tested for range of motion before surgery and reconstruction. A complete C6 corpectomy was performed and an interbody strut spacer with load cell was placed along with an anterior plate. Range of motion was measured with ±2.5 Nm of torque in flexion-extension, lateral bending, and axial rotation. Load-sharing data were recorded with incremental axial loads. The PLL was excised and range of motion and load-sharing testing was repeated.

RESULTS

There were no significant differences in range of motion or load sharing with an anterior corpectomy and reconstruction after PLL excision.

CONCLUSIONS

Excision of the PLL during anterior cervical corpectomy reconstructed with a strut graft and anterior plate does not significantly affect the construct stability or load sharing of the graft.

Complications following central corpectomy in 468 consecutive patients with degenerative cervical spine disease

OBJECTIVE

This study was performed to describe the incidence and predictors of perioperative complications following central corpectomy (CC) in 468 consecutive patients with cervical spondylotic myelopathy (CSM) or ossification of the posterior longitudinal ligament (OPLL).

METHODS

The authors performed a retrospective review of a cohort of patients who had undergone surgery for CSM (n = 338) or OPLL (n = 130) performed by a single surgeon over a 15-year period. All patients underwent uninstrumented CC with autologous iliac crest or fibular strut grafting. Preoperative clinical and imaging details were collected, and the type and incidence of complications were studied. Univariate and multivariate analyses were performed to establish risk factors for the development of perioperative complications.

RESULTS

Overall, 12.4% of patients suffered at least 1 complication following CC. The incidence of major complications was as follows: C-5 radiculopathy, 1.3%; recurrent laryngeal nerve injury, 0.4%; dysphagia, 0.8%; surgical-site infection, 3.4%; and dural tear, 4.3%. There was 1 postoperative death (0.2%). On multivariate analysis, patients in whom the corpectomy involved the C-4 vertebral body (alone or as part of multilevel CC) were significantly more likely to suffer complications (p = 0.004). OPLL and skip corpectomy were risk factors for dural tear (p = 0.015 and p = 0.001, respectively). No factors were found to be significantly associated with postoperative C-5 palsy, dysphagia, or acute graft extrusion on univariate or multivariate analysis. Patients who underwent multilevel CC were predisposed to surgical-site infections, with a slight trend toward statistical significance (p = 0.094). The occurrence of a complication after surgery significantly increased the mean duration of postoperative hospital stay from 5.0 ± 2.3 days to 8.9 ± 6 days (p < 0.001).

CONCLUSIONS

Complications following CC for CSM or OPLL are infrequent, but they significantly prolong hospital stay. The most frequent complication following CC is dural tear, for which a diagnosis of OPLL and a skip corpectomy are significant risk factors.

Long-term results of anterior cervical corpectomy and fusion with nano-hydroxyapatite/polyamide 66 strut for cervical spondylotic myelopathy

To assess the long-term clinical and radiographic outcomes of anterior cervical corpectomy and fusion (ACCF) with a neotype nano-hydroxyapatite/polyamide 66 (n-HA/PA66) strut in the treatment of cervical spondylotic myelopathy (CSM). Fifty patients with CSM who underwent 1- or 2-level ACCF with n-HA/PA66 struts were retrospectively investigated. With a mean follow-up of 79.6 months, the overall mean JOA score, VAS and cervical alignment were improved significantly. At last follow-up, the fusion rate was 98%, and the subsidence rate of the n-HA/PA66 strut was 8%. The "radiolucent gap" at the interface between the n-HA/PA66 strut and the vertebra was further noted to evaluate the osteoconductivity and osseointegration of the strut, and the incidence of it was 62% at the last follow-up. Three patients suffered symptomatic adjacent segment degeneration (ASD). No significant difference was detected in the outcomes between 1- and 2-level corpectomy at follow-ups. In conclusion, the satisfactory outcomes in this study indicated that the n-HA/PA66 strut was an effective graft for cervical reconstruction. Moreover, the osteoconductivity and osseointegration of the strut is still need to be optimized for future clinical application owing to the notably presence of "radiolucent gap" in present study.

Anterior Cervical Reconstruction Using Free Vascularized Fibular Graft after Cervical Corpectomy

Study Design Prospective study. Objective The aim of this study was to evaluate the clinical and radiologic results of using free vascularized fibular graft (FVFG) for anterior reconstruction of the cervical spine following with varying levels of corpectomy. Methods Ten patients underwent anterior cervical reconstruction using an FVFG after cervical corpectomy augmented with internal instrumentation. All patients were evaluated neurologically according to the Japanese Orthopaedic Association (JOA) and modified JOA scoring systems and the Nurick grading system. The neurologic recovery rate was determined, and the clinical outcome was assessed based on three factors: neck pain, dependence on pain medication, and ability to return to work. The fusion status and maintenance of lordotic correction by the strut graft were determined by measuring the lordosis angle and fused segment height (FSH). Results All patients achieved successful fusion. The mean follow-up period was 35.2 months (range, 28 to 44 months). Graft union occurred at a mean of 3.5 months. The mean loss of lordotic correction was 0.95 degrees, and the mean change in FSH was <1 mm. The neurologic recovery rate was excellent in four patients, good in five, and fair in one. All patients achieved satisfactory clinical outcome. No neurologic injuries occurred during the operations. Conclusion The use of FVFG is a valuable and effective technique in anterior cervical reconstruction for complex disorders.

Anterior Cervical Corpectomy with free vascularized fibular graft versus multilevel discectomy and grafting for Cervical Spondylotic Myelopathy

PURPOSE

A retrospective study to compare the radiologic and clinical outcomes of 2 different anterior approaches, multilevel anterior cervical discectomy with fusion (ACDF) using autologus ticortical bone graft versus anterior cervical corpectomy with fusion (ACCF) using free vascularized fibular graft (FVFG) for the management of cervical spondylotic myelopathy(CSM).

METHODS

A total of 15 patients who underwent ACDF or ACCF using FVFG for multilevel CSM were divided into two groups. Group A (n = 7) underwent ACDF and group B (n = 8) ACCF. Clinical outcomes using Japanese Orthopaedic Association (JOA) score, perioperative parameters including operation time and hospital stay, radiological parameters including fusion rate and cervical lordosis, and complications were compared.

RESULTS

Both group A and group B demonstrated significant increases in JOA scores. Patients who underwent ACDF experienced significantly shorter operation times and hospital stay. Both groups showed significant increases in postoperative cervical lordosis and achieved the same fusion rate (100 %). No major complications were encountered in both groups.

CONCLUSION

Both ACDF and ACCF using FVFG provide satisfactory clinical outcomes and fusion rates for multilevel CSM. However, multilevel ACDF is associated with better radiologic parameters, shorter hospital stay and shorter operative times.

Value of intraoperative neurophysiological monitoring to reduce neurological complications in patients undergoing anterior cervical spine procedures for cervical spondylotic myelopathy

The primary aim of this study was to conduct a systematic review of reports of patients with cervical spondylotic myelopathy and to assess the value of intraoperative monitoring (IOM), including somatosensory evoked potentials, transcranial motor evoked potentials and electromyography, in anterior cervical procedures. A search was conducted to collect a small database of relevant papers using key words describing disorders and procedures of interest. The database was then shortlisted using selection criteria and data was extracted to identify complications as a result of anterior cervical procedures for cervical spondylotic myelopathy and outcome analysis on a continuous scale. In the 22 studies that matched the screening criteria, only two involved the use of IOM. The average sample size was 173 patients. In procedures done without IOM a mean change in Japanese Orthopaedic Association score of 3.94 points and Nurick score by 1.20 points (both less severe post-operatively) was observed. Within our sub-group analysis, worsening myelopathy and/or quadriplegia was seen in 2.71% of patients for studies without IOM and 0.91% of patients for studies with IOM. Variations persist in the existing literature in the evaluation of complications associated with anterior cervical spinal procedures. Based on the review of published studies, sufficient evidence does not exist to make recommendations regarding the use of different IOM modalities to reduce neurological complications during anterior cervical procedures. However, future studies with objective measures of neurological deficits using a specific IOM modality may establish it as an effective and reliable indicator of injury during such surgeries.

Post laminoplasty cervical kyphosis-Case report

INTRODUCTION

Cervical kyphosis is a progressive cervical sagittal plane deformity that may cause a reduction in the ability to look horizontally, breathing and swallowing difficulties, sense of thoracic oppression and social isolation. Moreover, cervical kyphosis can cause myelopathy due to a direct compression by osteo-articular structures on the spinal cord or to a transitory ischaemic injury. The treatment of choice is surgery. The goals of surgery are: nervous structures decompression, cervical and global sagittal balance correction and vertebral stabilization and fusion.

PRESENTATION OF CASE

In October 2008 a 35 years old woman underwent surgical removal of a cervical-bulbar ependymoma with C1-C5 laminectomy and a C2-C5 laminoplasty. Five months after surgery, the patient developed a kyphotic posture, with intense neck and scapular girdle pain. The patients had a flexible cervical kyphosis. Therefore, we decided to perform an anterior surgical approach. We performed a corpectomy C4-C5 in order to achieve the anterior decompression; we placed a titanium expansion mesh.

DISCUSSION

Cervical kyphosis can be flexible or fixed. Some authors have reported the use of anterior surgery only for flexible cervical kyphosis as discectomy and corpectomy. This approach is useful for anterior column load sharing however it is not required for deformity correction.

CONCLUSION

The anterior approach is a good surgical option in flexible cervical kyphosis. It is of primary importance the sagittal alignment of the cervical spine in order to decompress the nervous structures and to guarantee a long-term stability.

Functional assessment of patients with cervical myelopathy who underwent surgical treatment

OBJECTIVE: Evaluate and correlate the functional response of patients with cervical myelopathy with the current clinical scores in patients who underwent surgical treatment. METHODS: We analyzed medical records of 34 patients with cervical myelopathy who underwent four different types of surgery. All patients were evaluated preoperatively and postoperatively with the application of the JOA and Nurick questionnaires. RESULTS: Functional clinical improvement was statistically significant. The mean preoperative JOA was 8.5 ± 3.06 and 10.7 ± 3.9 in the postoperative; Nurick was 3.2 ± 1.1 preoperatively and 2.8 ± 1.3 postoperatively. CONCLUSION: There is benefit with the surgical procedure in patients with cervical myelopathy. The neurological function after surgery depends on the previous function (the higher the duration of the previous symptoms, the greater the progression of the disease and, therefore, worse the neurological function) and the age is not a relevant factor of improvement, as already shown in other series. The clinical functional improvement of patients is visible with surgical treatment, regardless of surgical technique.

Biomechanical comparison of a two-level anterior discectomy and a one-level corpectomy, combined with fusion and anterior plate reconstruction in the cervical spine

BACKGROUND

Common fusion techniques for cervical degenerative diseases include two-level anterior discectomy and fusion and one-level corpectomy and fusion. The aim of the study was to compare via in-vitro biomechanical testing the effects of a two-level anterior discectomy and fusion and a one-level corpectomy and fusion, with anterior plate reconstruction.

METHODS

Seven fresh frozen human cadaveric spines (C3-T1) were dissected from posterior musculature, preserving the integrity of ligaments and intervertebral discs. Initial biomechanical testing consisted of no-axial preload and 2Nm in flexion-extension, lateral bending and axial rotation. Thereafter, discectomies were performed at C4-5 and C5-6 levels, then two interbody cages and an anterior C4-C5-C6 plate was implanted. The flexibility tests were repeated and followed by C5 corpectomy and C4-C6 plate reconstruction. Biomechanical testing was performed again and statistical comparisons among the means of range of motion and axial rotation energy loss were investigated.

FINDINGS

The two-level cage-plate construct had significantly lower range of motion than the one-level corpectomy-plate construct (P≤0.03). Axial rotation energy loss was significantly (P≤0.03) greater for the corpectomy-plate construct than for the two-level cage-plate construct and the intact condition.

INTERPRETATION

A two-level cage-plate construct provides greater stability in flexion, extension and lateral bending motions when compared to a one-level corpectomy-plate construct. A two-level cage-plate is more likely to maintain axial balance by reducing the energy lost in axial rotation.

Neurologic Outcome of Laminoplasty for Acute Traumatic Spinal Cord Injury without Instability

Objective

The purpose of this study is to evaluate the efficacy of laminoplasty in the treatment of spinal cord injury (SCI) without instability.

Methods

79 patients with SCI without instability who underwent surgical treatment in our institute between January 2005 and September 2012 were retrospectively reviewed. Twenty nine patients fulfilled the inclusion criteria as follows: SCI without instability, spinal cord contusion in MRI, cervical stenosis more than 20%, follow up at least 6 months. Preoperative neurological state, clinical outcome and neurological function was measured using the American Spinal Injury Association (ASIA) impairment scale, modified Japanese Orthopedic Association (mJOA) grading scale and Hirabayashi recovering rate.

Results

Seventeen patients showed improvement in ASIA grade and twenty six patients showed improvement in mJOA scale at 6 month follow up. However, all patients with ASIA grade B and C have shown improvement of one or more ASIA grade. Mean Hirabayashi recovery rate was 47.4±23.7%. There was better neurologic recovery in those who had cervical spondylosis without ossification of posterior longitudinal ligament (OPLL) (p<0.05, χ² test).

Conclusions

It is different in B, C, D with ASIA A that there are debates going on about the application of surgical treatment in ASIA A, and surgical treatment is helpful in B, C, D since it contributes to neurologic improvement. We concluded that laminoplasty provided good neurologic recovery in SCI without instability that cervical canal stenosis, especially spondylosis without OPLL and neurologic deterioration in ASIA B, C and D.

Clinical predictors of surgical outcome in cervical spondylotic myelopathy: an analysis of 248 patients

The purpose of this study was to investigate the clinical predictors of surgical outcome in patients with cervical spondylotic myelopathy (CSM). We reviewed a consecutive series of 248 patients (71 women and 177 men) with CSM who had undergone surgery at our institution between January 2000 and October 2010. Their mean age was 59.0 years (16 to 86). Medical records, office notes, and operative reports were reviewed for data collection. Special attention was focused on pre-operative duration and severity as well as post-operative persistence of myelopathic symptoms. Disease severity was graded according to the Nurick classification. Our multivariate logistic regression model indicated that Nurick grade 2 CSM patients have the highest chance of complete symptom resolution (p < 0.001) and improvement to normal gait (p = 0.004) following surgery. Patients who did not improve after surgery had longer duration of myelopathic symptoms than those who did improve post-operatively (17.85 months (1 to 101) vs 11.21 months (1 to 69); p = 0.002). More advanced Nurick grades were not associated with a longer duration of symptoms (p = 0.906). Our data suggest that patients with Nurick grade 2 CSM are most likely to improve from surgery. The duration of myelopathic symptoms does not have an association with disease severity but is an independent prognostic indicator of surgical outcome.

Clinical and radiological outcomes in 153 patients undergoing oblique corpectomy for cervical spondylotic myelopathy

OBJECTIVE

To document the clinical and radiological outcomes in a large series of patients undergoing the oblique cervical corpectomy (OCC) for spondylotic myelopathy.

MATERIALS AND METHODS

We retrospectively analyzed our series of 153 patients undergoing OCC for cervical spondylotic myelopathy (CSM) over the last 10 years. A mean clinical follow-up of 3 years was obtained in 125 patients (81.7%), while 117 patients (76.5%) were followed up radiologically. Neurological function was measured by the Nurick grade and the modified Japanese Orthopedic Association score (JOA). Plain radiographs and magnetic resonance images (MRI) were reviewed.

RESULTS

Ninety-two percent were men with a mean age of 51 years and a mean duration of symptoms of 18 months. Sixty-one had a single level corpectomy, 66 had a 2-level, 24 had a 3-level, and two had a 4-level OCC. There was statistically significant improvement (p < 0.05) in both the Nurick grade and the JOA score at mean follow-up of 34.6 ± 25.4 months. Permanent Horner's syndrome was seen in nine patients (5.9%), postoperative C5 radiculopathy in five patients (3.3%), dural tear with CSF leak in one patient (0.7%), and vertebral artery injury in one patient (0.7%). Of the 117 patients who were followed up radiologically, five patients (4.3%) developed an asymptomatic kyphosis of the cervical spine while 22 patients (25.6%) with preoperative lordotic spines had a straightening of the whole spine curvature.

CONCLUSIONS

The OCC is a safe procedure with good outcomes and a low morbidity for treating cervical cord compression due to CSM. This procedure avoids graft-related complications associated with the central corpectomy, but is technically demanding.

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.

Long term results of anterior corpectomy and fusion for cervical spondylotic myelopathy

Background

Results showed good clinical outcomes of anterior corpectomy and fusion (ACCF) for patients with cervical spondylotic myelopathy (CSM) during a short term follow-up; however, studies assessing long term results are relatively scarce. In this study we intended to assess the long term clinical and radiographic outcomes, find out the factors that may affect the long term clinical outcome and evaluate the incidence of adjacent segment disease (ASD).

Methods

This is a retrospective study of 145 consecutive CSM patients on ACCF treatment with a minimum follow-up of 5 years. Clinical data were collected from medical and operative records. Patients were evaluated by using the Japanese Orthopedic Association (JOA) scoring system preoperatively and during the follow-up. X-rays results of cervical spine were obtained from all patients. Correlations between the long term clinical outcome and various factors were also analyzed.

Findings

Ninety-three males and fifty-two females completed the follow-up. The mean age at operation was 51.0 years, and the mean follow-up period was 102.1 months. Both postoperative sagittal segmental alignment (SSA) and the sagittal alignment of the whole cervical spine (SACS) increased significantly in terms of cervical lordosis. The mean increase of JOA was 3.8±1.3 postoperatively, and the overall recovery rate was 62.5%. Logistic regression analysis showed that preoperative duration of symptoms >12 months, high-intensity signal in spinal cord and preoperative JOA score ≤9 were important predictors of the fair recovery rate (≤50%). Repeated surgery due to ASD was performed in 7 (4.8%) cases.

Conclusions

ACCF with anterior plate fixation is a reliable and effective method for treating CSM in terms of JOA score and the recovery rate. The correction of cervical alignment and the repeated surgery rate for ASD are also considered to be satisfactory.

Ossification of the posterior longitudinal ligament: pathogenesis, management, and current surgical approaches. A review

Ossification of the posterior longitudinal ligament (OPLL) is an important cause of cervical myelopathy that results from bony ossification of the cervical or thoracic posterior longitudinal ligament (PLL). It has been estimated that nearly 25% of patients with cervical myelopathy will have features of OPLL. Patients commonly present in their mid-40s or 50s with clinical evidence of myelopathy. On MR and CT imaging, this can be seen as areas of ossification that commonly coalesce behind the cervical vertebral bodies, leading to direct ventral compression of the cord. While MR imaging will commonly demonstrate associated changes in the soft tissue, CT scanning will better define areas of ossification. This can also provide the clinician with evidence of possible dural ossification. The surgical management of OPLL remains a challenge to spine surgeons. Surgical alternatives include anterior, posterior, or circumferential decompression and/or stabilization. Anterior cervical stabilization options include cervical corpectomy or multilevel anterior cervical corpectomy and fusion, while posterior stabilization approaches include instrumented or noninstrumented fusion or laminoplasty. Each of these approaches has distinct advantages and disadvantages. While anterior approaches may provide more direct decompression and best improve myelopathy scores, there is soft-tissue morbidity associated with the anterior approach. Posterior approaches, including laminectomy and fusion and laminoplasty, may be well tolerated in older patients. However, there often is associated axial neck pain and less improvement in myelopathy scores. In this review, the authors discuss the epidemiology, imaging findings, and clinical presentation of OPLL. The authors additionally discuss the merits of the different surgical techniques in the management of this challenging disease.

Multilevel oblique corpectomy for cervical spondylotic myelopathy preserves segmental motion

PURPOSE

To document the neurological outcome, spinal alignment and segmental range of movement after oblique cervical corpectomy (OCC) for cervical compressive myelopathy.

METHODS

This retrospective study included 109 patients--93 with cervical spondylotic myelopathy and 16 with ossified posterior longitudinal ligament in whom spinal curvature and range of segmental movements were assessed on neutral and dynamic cervical radiographs. Neurological function was measured by Nurick's grade and modified Japanese Orthopedic Association (JOA) scores. Eighty-eight patients (81%) underwent either a single- or two-level corpectomy; the remaining (19%) undergoing three- or four-level corpectomies. The average duration of follow-up was 30.52 months.

RESULTS

The Nurick's grade and the JOA scores showed statistically significant improvements after surgery (p < 0.001). The mean postoperative segmental angle in the neutral position straightened by 4.7 ± 6.5°. The residual segmental range of movement for a single-level corpectomy was 16.7° (59.7% of the preoperative value), for two-level corpectomy it was 20.0° (67.2%) and for three-level corpectomies it was 22.9° (74.3%). 63% of patients with lordotic spines continued to have lordosis postoperatively while only one became kyphotic without clinical worsening. Four patients with preoperative kyphotic spines showed no change in spine curvature. None developed spinal instability.

CONCLUSIONS

The OCC preserves segmental motion in the short-term, however, the tendency towards straightening of the spine, albeit without clinical worsening, warrants serial follow-up imaging to determine whether this motion preservation is long lasting.

Long-term follow-up of cervical radiographic sagittal spinal alignment after 1- and 2-level cervical corpectomy for the treatment of spondylosis of the subaxial cervical spine causing radiculomyelopathy or myelopathy: a retrospective study

Object

Few data exist regarding long-term outcomes after cervical corpectomy for spondylotic cervical myelopathy and radiculomyelopathy. In this retrospective review, long-term radiographic outcomes are reported for 130 patients after 1- or 2-level cervical corpectomy for spondylotic myelopathy or radiculomyelopathy.

Methods

Electronic medical records including clinical data and radiographic images during a 15-year period (1993–2008) were reviewed at the Cincinnati Department of Veterans Affairs Medical Center. All patients underwent radiographic follow-up for at least 12 months (range 12–156, mean 45 ± 39.3 months), as well as clinical follow-up performed by neurosurgery staff for a mean of 29.3 ± 39.6 months (range 4–156 months). Clinical parameters at surgery and last examination included the Chiles modified Japanese Orthopaedic Association (mJOA) Myelopathy Scale. Measurements included cervical spine sagittal alignment on lateral radiographs preoperatively and postoperatively, focal Cobb angles at operated levels, and C2–7 regional alignment. Statistical analysis included the Student t-test and chi-square test. Perioperative complications and additional surgery in the cervical spine were recorded.

Results

The mJOA scores improved from a mean of 11.91 ± 2.4 preoperatively to 14.9 ± 2.33 postoperatively. The mean sagittal lordosis of the C2–7 spine increased from −16.2° ± 9.2° preoperatively to −18.5° ± 11.9° at last follow-up. Focal Cobb angles averaged a slight kyphotic angulation of 4.1° ± 2.3° at latest radiographic follow-up; of note, 7 patients (5.4%), all who had cylindrical titanium mesh cages (CTMCs), showed severe kyphotic angulation (+8.4° ± 2.4°). Patients with preoperative myelopathy showed clinical improvement at follow-up. The fusion rate was 96.2%; 3 of the 5 patients with radiographic evidence of nonfusion were smokers. Patients with postoperative kyphosis had significantly more chronic neck pain (visual analog scale score >4 lasting more than 6 months) and visits related to pain (p <0.01). Those with CTMCs had higher rates of postoperative kyphosis, chronic neck pain, and visits related to pain, irrespective of the number of levels fused (p <001). At latest follow-up, although a kyphotic increase occurred in the focal cervical sagittal Cobb angles, lordosis increased in C2–7 sagittal Gore angles. Two patients (1.5%) underwent revision of the implanted graft and/or hardware, and 5 patients (3.8%) had another procedure for adjacent-level pathologies 1–9 years later (mean 4.4 ± 2.7 years).

Conclusions

Long-term follow-up data in our veteran population support cervical corpectomy as an effective, long-lasting treatment for spondylotic myelopathy of the cervical spine. Use of CTMCs without end caps was associated with statistically significant increased postoperative kyphotic angulation and chronic pain. Despite an increase in focal kyphosis over time, regional cervical sagittal lordotic alignment had increased at the latest follow-up. Further investigation will include the association of chronic neck pain and postoperative kyphosis, and high fusion rates among a veteran population of heavy smokers.

Anterior corpectomy and reconstruction with titanium mesh cage and dynamic cervical plate for cervical spondylotic myelopathy in elderly osteoporosis patients

OBJECTIVE

This retrospective study was to evaluate the relationship between osteoporosis and dynamic cervical plates in screw-plate or screw-bone interface of elderly cervical spondylotic myelopathy (CSM) patients.

METHODS

Retrospective study was conducted on elderly CSM patients, treated by anterior corpectomy and reconstruction with titanium mesh cages (TMC) and dynamic cervical plate between July 2004 and June 2007. All patients underwent bone mineral density (BMD) assessment in preoperation, and according to the osteoporosis degree they have been divided into two groups: moderate osteoporosis degree group and severe osteoporosis degree group. The clinical outcome [Japanese Orthopaedic Association score (JOA) and Visual Analogue Scale (VAS)], bone fusion assessment (CT mielogram), the change of titanium mesh cages and plate of cephalic screw-plate-angle (SPA) and cephalic endplate-plate-angle (EPA) of plain X-ray films were measured.

RESULTS

The mean JOA score and recovery rate were not different between the two groups (P > 0.05). There was no loss of sagittal alignment after surgery in any patient, and no significant difference between both groups on lordosis measurements (P > 0.05). Although there was a significant difference of the cage subsidence rate between the two groups (P < 0.001), all patients had favorable bone union and none required additional treatment. The average changes of SPA were greater in A group patients than in B group patients, while the variation of EPA was higher in B group patients than in A group patients (P < 0.001).

CONCLUSIONS

Despite the fact that there is a significant difference of the cage subsidence rate between the two groups no clinical outcome, nor sagittal alignment or fusion rate differences among groups was observed in elderly CSM patients.

Anterior surgery in selective patients with massive ossification of posterior longitudinal ligament of cervical spine: technical note

STUDY DESIGN

The study includes case series, technical note and review of literature.

OBJECTIVE

The objective of this study was to assess the validity of the radiographic indicator and the result of anterior operation for massive ossification of posterior longitudinal ligament (MOPLL, ossification of posterior longitudinal ligament with an occupying ratio exceeding 50%). Anterior decompression yielded a better outcome than posterior approach in patients with MOPLL of cervical spine. But anterior surgery has the problem of technically demanding and was associated with a high incidence of surgery-related complications. Many ways for reducing the risk of anterior surgery have been reported, including floating method, employing microscopes or burrs, and laser-assisted corpectomy.

MATERIALS AND METHODS

A case series of selective patients with MOPLL of cervical spine undergoing anterior surgery is reported. All patients were strictly selected based on CT images with the appearance of open-base. 29 cases with more than 12 months follow-up (average, 31.0 ± 10.0 m) were reviewed. Average age at operation was 59.3 ± 8.2 years (43-73 years). Anterior decompression was done only for one or two vertebrae.

RESULTS

One corpectomy was done in 13 cases, two corpectomies in 3 cases, and one corpectomy and one discectomy in 13 cases. Three levels were fused in 16 cases and two levels in 13 cases. No permanent neurological deterioration was observed. Neurological improvement was observed in every patients with an average improvement rate of 64 ± 23%. Mesh migration was observed in one case. A fusion rate of 100% was achieved.

CONCLUSION

Anterior surgery using our technique may be a relatively simple and safe procedure in selective patients with massive ossification of posterior longitudinal ligament of cervical spine.

A comparison of anterior cervical discectomy and corpectomy in patients with multilevel cervical spondylotic myelopathy

BACKGROUND

The optimal surgical approach for multilevel cervical spondylotic myelopathy (CSM) has not been defined, and the relative merits of multilevel anterior cervical discectomy and fusion (ACDF) and anterior cervical corpectomy (2-level or skip 1-level corpectomy) and fusion (ACCF) remain controversial. However, few comparative studies have been conducted on these two surgical approaches.

METHODS

This study retrospectively reviewed the case histories of 120 patients that underwent surgical treatment for 3- or 4-level CSM from July 2003 to June 2008. One hundred and twenty patients (81 male and 39 female) of mean age 58.3±9.8 years (37-78) were included. The study compared perioperative parameters (blood loss, operation times), complications [surgery-related complications (CSF, hoarseness, epidural hematoma, C5-palsy, dysphagia), instrumentation and graft related complications (dislodgement, subsidence)], clinical parameters [Japanese Orthopedic Association (JOA) scores, Neck Dysfunciton Index (NDI) scores], and radiologic parameters (segmental lordosis, fusion rate).

RESULTS

At a minimum of 2-year follow-up, both ACDF and ACCF groups demonstrated a significant increase in the JOA scores (preoperatively 9.25±1.9 and 8.86±1.9, postoperatively 13.86±1.6 and 13.27±1.8, respectively), segmental lordosis (preoperatively 9.79±3.4 and 9.54±3.0, postoperatively 17.75±2.6 and 14.49±2.5, respectively) and NDI scores (preoperatively 12.56±3.0 and 12.21±3.4, postoperatively 3.44±1.7 and 5.68±2.6, respectively). Six patients (2 dislodgement, 4 subsidence) in ACCF group had instrumentation and graft related-complications and they had no obvious neurological symptoms without a second operation. Blood loss (102.81±51.3 and 149.05±74, respectively, P=0.000), NDI scores (P=0.000), and instrumentation and graft related-complications (P=0.032) were significantly lower in the ACDF group, whereas operation time (138.07±30.9 and 125.08±26.4, respectively, P=0.021) and segmental lordosis (P=0.000) were significantly greater in the ACDF group. Other parameters were not significantly different in the two groups.

CONCLUSIONS

Surgical managements of 3- or 4-level CSM by ACDF or ACCF showed no significant differences in terms of achieved clinical symptom improvements, with the exception of better postoperative NDI scores in ACDF. In addition, ACDF is better than ACCF in terms of blood loss, lordotic curvature improvement and instrumentation and graft related-complication rates, with the exception of operation times.

The relevance of intramedullary high signal intensity and gadolinium (Gd-DTPA) enhancement to the clinical outcome in cervical compressive myelopathy

PURPOSE

We prospectively investigated whether high intramedullary SI and contrast [gadolinium-diethylene-triamine-pentaacetic acid (Gd-DTPA)] enhancement in magnetic resonance imaging (MRI) are associated with postoperative prognosis in cervical compressive myelopathy (CCM) patients.

METHODS

Seventy-four patients with ventral cord compression at one or two levels underwent anterior cervical discectomy and fusion (ACDF) for CCM between March 2006 and June 2009. The mean follow-up period was 39.7 months (range, 12.7-55.7 months). The cervical cord compression ratio and clinical outcomes were measured using Japanese Orthopedic Association (JOA) scores for cervical myelopathy. Patients were classified into three groups based on the SI change in T2WI, T1-weighted images (T1WI), and contrast (Gd-DTPA) enhancement.

RESULTS

The mean preoperative and postoperative JOA scores were 10.5 ± 2.9 and 15.0 ± 2.1 (P < 0.05), respectively. The mean recovery ratio of the JOA score was 70.9 ± 20.2%. There were statistically significant differences in postoperative JOA and recovery ratio among three groups. However, post-surgical neurological outcomes were not associated with age, symptom duration, preoperative JOA, and cord compression.

CONCLUSIONS

We found that intramedullary SI change is a poor prognostic factor and the intramedullary contrast (Gd-DTPA) enhancement on preoperative MRI should be viewed as the worst predictor of surgical outcomes in cervical myelopathy. Contrast (Gd-DTPA) enhancement and postoperative MRI are useful for identifying the prognosis of patients with poor neurological recovery.

The value of intraoperative ultrasound in oblique corpectomy for cervical spondylotic myelopathy and ossified posterior longitudinal ligament

Intraoperative ultrasound (IOUS) has been described to be useful during central corpectomy for compressive cervical myelopathy. This study aimed at documenting the utility of IOUS in oblique cervical corpectomy (OCC). Prospective data from 24 patients undergoing OCC for cervical spondylotic myelopathy and ossified posterior longitudinal ligament (OPLL) were collected. Patients had a preoperative cervical spine magnetic resonance (MR) image, IOUS and a postoperative cervical CT scan. Retrospective data from 16 historical controls that underwent OCC without IOUS were analysed to compare the incidence of residual compression between the two groups. IOUS identified the vertebral artery in all cases, detected residual cord compression in six (27%) and missed compression in two cases (9%). In another two cases with OPLL, IOUS was sub-optimal due to shadowing. IOUS measurement of the corpectomy width correlated well with these measurements on the postoperative CT. The extent of cord expansion noted on IOUS after decompression showed no correlation with immediate or 6-month postoperative neurological recovery. No significant difference in residual compression was noted in the retrospective and prospective groups of the study. Craniocaudal spinal cord motion was noted after the completion of the corpectomy. IOUS is an inexpensive and simple real-time imaging modality that may be used during OCC for cervical spondylotic myelopathy. It is helpful in identifying the vertebral artery and determining the trajectory of approach, however, it has limited utility in patients with OPLL due to artifacts from residual ossification.

Functional and clinical outcomes following surgical treatment in patients with cervical spondylotic myelopathy: a prospective study of 81 cases

Object

Cervical spondylotic myelopathy (CSM) is the most common cause of spinal dysfunction in the elderly. Operative management is beneficial for most patients with moderate/severe myelopathy. This study examines the potential confounding effects of age, sex, duration of symptoms, and comorbidities on the functional outcomes and postoperative complications in patients who underwent cervical decompressive surgery.

Methods

We included consecutive patients who underwent surgery from December 2005 to October 2007. Functional outcomes were assessed using the Nurick grading system and the modified Japanese Orthopaedic Association and Berg Balance scales. Comorbidity indices included the Charlson Comorbidity Index and the number of ICD-9 codes.

Results

There were 57 men and 24 women with a mean age of 57 years (range 32–88 years). The mean duration of symptoms was 25.2 months (range 1–120 months). There was a significant functional recovery from baseline to 6 months after surgery (p < 0.01). Postoperative complications occurred in 18.5% of cases. Although the occurrence of complications was not significantly associated with sex (p = 0.188), number of ICD-9 codes (p = 0.113), duration of symptoms (p = 0.309), surgical approach (p = 0.248), or number of spine levels treated (p = 0.454), logistic regression analysis showed that patients who developed complications were significantly older than patients who had no complications (p = 0.018). Only older age (p < 0.002) and greater number of ICD-9 codes (p < 0.01) were significantly associated with poorer functional recovery after surgical treatment. However, none of the studied factors were significantly associated with clinically relevant functional recovery after surgical treatment for CSM (p > 0.05).

Conclusions

Our results indicate that surgery for CSM is associated with significant functional recovery, which appears to reach a plateau at 6 months after surgery. Age is a potential predictor of complications after decompressive surgery for CSM. Whereas older patients with a greater number of preexisting medical comorbidities had less favorable functional outcomes after surgery for CSM in the multivariate regression analysis, none of the studied factors were associated with clinically relevant functional recovery after surgery in the logistic regression analysis. Therefore, age-matched protocols based on preexisting medical comorbidities may reduce the risk for postoperative complications and improve functional outcomes after surgical treatment for CSM.