Anterior corpectomy versus posterior laminoplasty: is the risk of postoperative C-5 palsy different?

Current Status and Trends of Research on Cervical Spondylotic Myelopathy from the Perspective of Bibliometrics

This review was performed to analyze the research on cervical spondylotic myelopathy published during the past 25 years, summarize the developments in existing research, and predict future hotspots in the field. The goal is to provide a comprehensive overview and exploration of developments in this research area. A bibliometric analysis was performed using CiteSpace and VOSviewer to quantitatively and visually analyze relevant literature from Web of Science between 1998 and 2023. Co-occurrence analysis and co-citation analysis were conducted to evaluate papers, authors, journals, countries, and keywords. In total, 1886 papers were included. The overall publication output in this field increased throughout the review period. Stable author collaboration groups were formed, with the most influential author being Fehlings M.G. Japan and the United States contributed the highest number of publications. The predicted future research hotspots include risk factor analysis, outcome prediction, and machine learning. This study provides both an overview of the research trajectory in the field of cervical spondylotic myelopathy for scholars interested in this area, as well as offering insights and references for future research directions in the field.

Technical Nuances of Cervical Laminoplasty: Supplemental Manuscript to Operative Video

STUDY DESIGN

Operative video and supplemental manuscript.

OBJECTIVE

The technical nuances of open-door laminoplasty are described. Potential complications of open-door laminoplasty and strategies for their minimization are discussed.

SUMMARY OF BACKGROUND DATA

Cervical laminoplasty may be indicated in patients with cervical myelopathy due to cervical stenosis in the setting of spondylosis, ossification of the posterior longitudinal ligament, congenital stenosis, and traumatic central cord syndrome.

METHODS

A video illustrates the nuances of the surgical technique for cervical laminoplasty.

RESULTS

Myelopathic patients with preserved lordotic sagittal profile, central stenosis involving several levels, and minimal to no axial neck pain are ideal candidates for laminoplasty.

CONCLUSIONS

Cervical laminoplasty provides more stability compared with laminectomy alone and a better range of motion compared with laminectomy with posterior spinal fusion. Understanding the nuances of laminoplasty may help surgeons to avoid complications.

Predictors of serious, preventable, and costly medical complications in a population of adult spinal deformity patients

BACKGROUND CONTEXT

In 2008, the Centers for Medicare and Medicaid Services (CMS) established a list of hospital-acquired conditions (HACs) with significant deleterious effects on both patients and providers. Adult spinal deformity (ASD) surgery is complex and highly invasive, and as such may result in significant morbidity including these HACs.

PURPOSE

Identify predictors for developing the most common HACs among adult spinal deformity (ASD) patients undergoing corrective surgery.

STUDY DESIGN/SETTING

Retrospective analysis.

PATIENT SAMPLE

One thousand one hundred and seventy-one ASD patients.

OUTCOME MEASURES

HACs, Health-Related Quality of Life scores(HRQLs), Reoperation, Integrated Health State (IHS) METHODS: ASD pts undergoing surgery (>18 years, scoliosis ≥20°, SVA ≥5 cm, PT ≥25° and/or TK >60°) with complete data at BL and up to 2 years post-op were included. Patients were stratified by presence of >1 HAC, defined as at least one superficial/deep SSI, UTI, DVT, or PE within a 30-day post-op window. Random forest analysis generated 5,000 Conditional Inference Trees to compute a variable importance table for top predictors of HACs. An area-under-the-curve (AUC) methodology compared normalized HRQL scores between groups to determine an IHS with 2-year follow-up.

RESULTS

Total of 1,171 pts (59.8 years, 76.2%F, 28.1kg/m²) underwent corrective ASD surgery, with 1,053 pts in the non-HAC group and 118 in the HAC group. Of these pts, 25.4% had UTI, 15.4% DVT, 19.2% superficial SSI, 20.8% deep SSI, and 19.2% PE. HAC pts were on average older (63.5 vs 59.3, p=.004) and more often frail (51.3 vs 39.7%, p=.021) than non-HAC pts. Postop LOS and reoperation were most associated with HAC groups: [1] LOS >7 days [2] reoperation. Patient-related predictors of HACs were [3] age >50 yerr, [4] frailty, and [13] BMI >31. Procedure-related predictors of HACs were [5] operative-time >405 minutes, [6] levels fused >9, EBL >1450 mL, and [11] decompression. BL radiographic predictors were [7] PT >20°, [9] PI-LL>6°, [10] TL Cobb angle >15°, [12] SVA C7-S1 >29 mm. No differences were observed between groups with regards to IHS ODI (0.73 vs 0.74, p=.863), SRS (1.3 vs1.3, p=.374), NRS Back (0.6 vs 0.6, p=.158). HAC had higher rates of reoperation than non-HAC (0.08 vs 0.01, p=.066), and any HAC within 30-days of index was a significant predictor of reoperation (OR: 2.448 [1.94-3.09], p<.001).

CONCLUSIONS

In a population of ASD patients, HACs were associated with length of stay, reoperation, age, and frailty. Radiographic parameters such as pelvic tilt >20°, PI-LL >6°, & SVA >29 mm also increased odds of HACs, and should raise postoperative awareness for HAC development.

Patterns of neurological deficits and recovery of postoperative C5 nerve palsy

OBJECTIVE

Paresis of the C5 nerve is a well-recognized complication of cervical spine surgery. Numerous studies have investigated its incidence and possible causes, but the specific pattern and character of neurological deficits, time course, and relationship to preoperative cord signal changes remain incompletely understood.

METHODS

Records of patients undergoing cervical decompressive surgery for spondylosis, disc herniation, or ossification of the longitudinal ligament, including the C4-5 level, were reviewed from a 15-year period, identifying C5 palsy cases. Data collected included age, sex, diabetes and smoking statuses, body mass index, surgical levels, approach, presence of increased cord signal intensity, and modified Japanese Orthopaedic Association (mJOA) scores. Narrative descriptions of the patterns and findings on neurological examination were reviewed, and complications were noted. The minimum follow-up requirement for the study was 12 months.

RESULTS

Of 642 patients who underwent cervical decompressive surgery, 18 developed C5 palsy (2.8%). The incidence was significantly lower following anterior surgery (6 of 441 [1.4%]) compared with that following cervical laminectomy and fusion (12 of 201 [6.0%]) (p < 0.001). There were 10 men and 8 women whose mean age was 66.7 years (range 54-76 years). The mean preoperative mJOA score of 11.4 improved to 15.6 at the latest follow-up examination. There were no differences between those with and without C5 palsy with regard to sex, age, number of levels treated, or pre- or postoperative mJOA score. Fifteen patients with palsy (83%) had signal changes/myelomalacia on preoperative T2-weighted imaging, compared with 436 of 624 (70%) patients without palsy; however, looking specifically at the C4-5 level, signal change/myelomalacia was present in 12 of 18 (67%) patients with C5 palsy, significantly higher than in the 149 of 624 (24%) patients without palsy (p < 0.00003). Paresis was unilateral in 16 (89%) and bilateral in 2 (11%) patients. All had deltoid weakness, but 15 (83%) exhibited new biceps weakness, 8 (44%) had triceps weakness, and 2 (11%) had hand intrinsic muscle weakness. The mean time until onset of palsy was 4.6 days (range 2-14 days). Two patients (11%) complained of shoulder pain preceding weakness; 3 patients (17%) had sensory loss. Recovery to grade 4/5 deltoid strength occurred in 89% of the patients. No patient had intraoperative loss of somatosensory or motor evoked potentials or abnormal intraoperative C5 electromyography activity.

CONCLUSIONS

Postoperative C5 nerve root dysfunction appears in a delayed fashion, is predominantly a motor deficit, and weakness is frequently appreciated in the biceps and triceps muscles in addition to the deltoid muscle. Preoperative cord signal change/myelomalacia at C4-5 was a significant risk factor. No patient had a detectable deficit in the immediate postoperative period or changes in intraoperative neuromonitoring status. Neurological recovery to at least that of grade 4/5 occurred in nearly 90% of the patients.

Choice and management of negative pressure drainage in anterior cervical surgery

BACKGROUND

Postoperative unobstructed drainage is an important measure for avoiding hematoma formation and preventing complications from anterior cervical surgery.

AIM

To discuss the characteristics and key points of clinical management of two types of commonly used negative pressure drainage systems in clinical settings.

METHODS

Two types of commonly used silica gel negative pressure drainage balls and a type of gastrointestinal decompression apparatus were fully emptied and then injected with different amounts of water and air. Following this, the negative pressure values of the three devices were measured. Meanwhile, we undertook a retrospective analysis of the clinical data of 1328 patients who had been treated with different negative pressure drainage apparatuses during their anterior cervical surgery in our department between January 2007 and January 2018.

RESULTS

As the amount of injected air or water increased, the negative pressure of the silica gel negative pressure drainage ball decreased rapidly, dropping to zero when 150 mL of water or air was injected. In contrast, the negative pressure of gastrointestinal decompression apparatus decreased slowly, maintaining an ideal value even when 300 mL of water or air was injected. And statistical analysis demonstrated that patients who had been treated with the gastrointestinal decompression apparatus were less likely to develop severe complications than those who had been treated with the silica gel negative pressure drainage ball (P < 0.05).

CONCLUSION

This study showed that the gastrointestinal decompression apparatus has the advantages of large suction capacity, long duration of continuous negative pressure, and good drainage effect, all of which are the favorable factors for the use of this apparatus for negative pressure drainage in anterior cervical surgery.

Postoperative Rigid Cervical Collar Leads to Less Axial Neck Pain in the Early Stage After Open-Door Laminoplasty-A Single-Blinded Randomized Controlled Trial

BACKGROUND

Cervical collars are used after laminoplasty to protect the hinge opening, reduce risks of hinge fractures, and avoid spring-back phenomena. However, their use may lead to reduced range of motion and worse neck pain.

OBJECTIVE

To investigate the clinical, radiological, and functional outcomes of patients undergoing single-door laminoplasty with or without collar immobilization.

METHODS

This was a prospective, parallel, single-blinded randomized controlled trial. Patients underwent standardized single-door laminoplasty with mini-plates for cervical myelopathy and were randomly allocated into 2 groups based on the use of collar postoperatively. Clinical assessments included cervical range of motion, axial neck pain (VAS [visual analogue scale]), and objective scores (short-form 36-item, neck disability index, and modified Japanese Orthopaedic Association). All assessments were performed preoperatively and at postoperative 1, 2, 3, and 6 wk, and 3, 6, and 12 mo. Comparative analysis was performed via analysis of variance adjusted by baseline scores, sex, and age as covariates.

RESULTS

A total of 35 patients were recruited and randomized to collar use (n = 16) and without (n = 19). There were no dropouts or complications. There were no differences between groups at baseline. Subjects had comparable objective scores and range of motion at postoperative time-points. Patients without collar use had higher VAS at postoperative 1 wk (5.4 vs 3.5; P = .038) and 2 wk (3.5 vs 1.5; P = .028) but subsequently follow-up revealed no differences between the 2 groups.

CONCLUSION

The use of a rigid collar after laminoplasty leads to less axial neck pain in the first 2 wk after surgery. However, there is no additional benefit with regards to range of motion, quality of life, and complication risk.

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.

Recent advances in the management of cervical spondylotic myelopathy: bibliometric analysis and surgical perspectives

OBJECTIVE

Cervical spondylotic myelopathy (CSM) has become a prevalent cause of spinal cord dysfunction among the aging population worldwide. Although great strides have been made in spine surgery in past decades, the optimal timing and surgical strategy to treat CSM have remained controversial. In this article the authors aimed to analyze the current trends in studies of CSM and to summarize the recent advances of surgical techniques in its treatment.

METHODS

The PubMed database was searched using the keywords pertaining to CSM in human studies that were published between 1975 and 2018. Analyses of both the bibliometrics and contents, including the types of papers, authors, affiliations and countries, number of patients, and the surgical approaches were conducted. A systematic review of the literature was also performed with emphasis on the diagnosis and treatment of mild CSM.

RESULTS

A total of 1008 papers published during the span of 44 years were analyzed. These CSM studies mainly focused on the natural history, diagnosis, and treatment, and only a few prospective randomized trials were reported. For the authors and affiliations, there was a shift of clustering of papers toward Asian countries in the past decades. Regarding the treatment for CSM, there was an exponential growth of surgical series published, and there was a trend toward slightly more anterior than posterior approaches through the past decade. Patients with CSM had increased risks of neurological deterioration or spinal cord injury with nonoperative management. Because surgery might reduce the risks, and early surgery was likely to be correlated with better outcomes, there was a trend toward attention to mildly symptomatic CSM.

CONCLUSIONS

There is emerging enthusiasm for research on CSM worldwide, with more publications originating in Asian countries over the past few decades. The surgical management of CSM is evolving continuously toward early and anterior approaches. More prospective investigations on the optimal timing and choices of surgery are therefore needed.

Ossification of the Posterior Longitudinal Ligament in Cervical Spine: Prevalence, Management, and Prognosis

Ossification of the posterior longitudinal ligament (OPLL) in the cervical spine and related neurological complications are not uncommon in East Asian countries. The estimated prevalence of cervical OPLL-related hospitalization is 7.7 per 100,000 person-years in Taiwan, and higher incidence rates have been observed in elderly and male patients. Although cervical OPLL is frequently insidious, it can eventually cause myelopathy and predispose patients to spinal cord injury (SCI). There are multiple options for managing cervical OPLL, ranging from observation to many kinds of surgical procedures, including posterior laminoplasty, laminectomy with or without fusion, anterior corpectomy with or without instrumentation, and circumferential decompression and fusion. None of these surgical approaches is free of complications. However, to date, there is still a lack of consensus regarding the choice of the surgical approach and the timing of surgical intervention. Cervical SCI and related neurological disabilities are more likely to occur in OPLL patients, who should therefore be cautioned regarding the possibility of a subsequent SCI if treated without surgery. This article aimed to review the prevalence, management strategies, and prognosis of cervical OPLL.

Comparable clinical and radiological outcomes between skipped-level and all-level plating for open-door laminoplasty

PURPOSE

To compare the clinical and radiological outcomes between skipped-level and all-level plating for cervical laminoplasty.

METHODS

Patients with cervical spondylotic myelopathy (CSM) treated by open-door laminoplasty with minimum 2-year postoperative follow-up were included. All patients had opening from C3-6 or C3-7 and were divided into skipped-level or all-level plating groups. Japanese Orthopaedic Association (JOA) scores and canal measurements were obtained preoperatively, immediate (within 1 week) postoperatively, and at 2, 6 weeks, 3, 6 and 12 months postoperatively. Paired t test was used for comparative analysis. Receiver operating characteristic analysis was used to determine the canal expansion cutoff for spring-back closure.

RESULTS

A total of 74 subjects were included with mean age of 66.1 ± 11.3 years at surgery. Of these, 32 underwent skipped-level plating and 42 underwent all-level plating. No significant differences were noted between the two groups at baseline and follow-up. Spring-back closure was observed in up to 50% of the non-plated levels within 3 months postoperatively. The cutoff for developing spring-back closure was 7 mm canal expansion for C3-6. No differences were observed in JOA scores and recovery rates between the two groups. None of the patients with spring-back required reoperation.

CONCLUSIONS

There were no significant differences between skipped-level and all-level plating in terms of JOA or recovery rate, and canal diameter differences. This has tremendous impact on saving costs in CSM management as up to two plates per patient undergoing a standard C3-6 laminoplasty may be omitted instead of four plates to every level to achieve similar clinical and radiological outcomes.

LEVEL OF EVIDENCE

III. These slides can be retrieved under Electronic Supplementary Material.

Management of degenerative cervical myelopathy - An update

Introduction

Degenerative cervical myelopathy (DCM) is the most common cause of spinal cord dysfunction in adult patients. Patients generally present with a slow, progressive neurological decline or a stepwise deterioration pattern. In this paper, we discuss the most important factors involved in the management of DCM, including a discussion about the surgical approaches.

Method

The authors performed an extensive review of the peer-reviewed literature addressing the aforementioned objectives.

Results

Although the diagnosis is clinical, magnetic resonance imaging (MRI) is the study of choice to confirm stenosis and also to exclude the differential diagnosis. The severity the clinical symptoms of DCM are evaluated by different scales, but the modified Japanese Orthopedic Association (mJOA) and the Nürick scale are probably the most commonly used. Spontaneous clinical improvement is rare and surgery is the main treatment form in an attempt to prevent further neurological deterioration and, potentially, to provide some improvement in symptoms and function. Anterior, posterior or combined cervical approaches are used to decompress the spinal cord, with adjunctive fusion being commonly performed. The choice of one approach over the other depends on patient characteristics (such as number of involved levels, site of compression, cervical alignment, previous surgeries, bone quality, presence of instability, among others) as well as surgeon preference and experience.

Conclusion

Spine surgeons must understand the advantages and disadvantages of all surgical techniques to choose the best procedure for their patients. Further comparative studies are necessary to establish the superiority of one approach over the other when multiple options are available.

A Comparison of Implants Used in Open-Door Laminoplasty: Structural Rib Allografts Versus Metallic Miniplates

STUDY DESIGN

A retrospective case-controlled study.

SUMMARY OF BACKGROUND DATA

Open-door laminoplasty has been successfully used to address cervical spondylotic myelopathy and ossification of the posterior longitudinal ligament. Two common implants include rib allograft struts and metallic miniplates.

OBJECTIVE

The goals of this study were to compare outcomes, complications, and costs associated with these 2 implants.

METHODS

A retrospective review was done on 51 patients with allograft struts and 55 patients with miniplates. Primary outcomes were neck visual analog scale (VAS) pain scores and Nurick scores. Secondary outcomes included length of the procedure, estimated blood loss, rates of complications, and the direct costs associated with the surgery and inpatient hospitalization.

RESULTS

There were no differences in demographic characteristics, diagnoses, comorbidities, and preoperative outcome scores between the 2 treatment groups. Mean follow-up was 27 months. The postoperative neck VAS scores and Nurick scores improved significantly from baseline to final follow-up for both groups, but there was no difference between the 2 groups. The average length of operation (161 vs. 136 min) and number of foraminotomies (2.7 vs. 1.3) were higher for the allograft group (P=0.007 and 0.0001, respectively). Among the miniplate group, there was no difference in complications but a trend for less neck pain for patients treated without hard collar at final follow-up (1.8 vs. 2.3, P=0.52). The mean direct costs of hospitalization for the miniplate group were 15% higher.

CONCLUSIONS

Structural rib allograft struts and metallic miniplates result in similar improvements in pain and functional outcome scores with no difference in the rate of complications in short-term follow-up. Potential benefits of using a plate include shorter procedure length and less need for postoperative immobilization. When costs of bracing and operative time are included, the difference in cost between miniplates and allograft struts is negligible.

C5 Palsy After Cervical Spine Surgery: A Multicenter Retrospective Review of 59 Cases

STUDY DESIGN

A multicenter, retrospective review of C5 palsy after cervical spine surgery.

OBJECTIVE

Postoperative C5 palsy is a known complication of cervical decompressive spinal surgery. The goal of this study was to review the incidence, patient characteristics, and outcome of C5 palsy in patients undergoing cervical spine surgery.

METHODS

We conducted a multicenter, retrospective review of 13 946 patients across 21 centers who received cervical spine surgery (levels C2 to C7) between January 1, 2005, and December 31, 2011, inclusive. P values were calculated using 2-sample t test for continuous variables and χ² tests or Fisher exact tests for categorical variables.

RESULTS

Of the 13 946 cases reviewed, 59 patients experienced a postoperative C5 palsy. The incidence rate across the 21 sites ranged from 0% to 2.5%. At most recent follow-up, 32 patients reported complete resolution of symptoms (54.2%), 15 had symptoms resolve with residual effects (25.4%), 10 patients did not recover (17.0%), and 2 were lost to follow-up (3.4%).

CONCLUSION

C5 palsy occurred in all surgical approaches and across a variety of diagnoses. The majority of patients had full recovery or recovery with residual effects. This study represents the largest series of North American patients reviewed to date.

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

STUDY DESIGN

A meta-analysis.

OBJECTIVE

To compare the effectiveness and the safety of the anterior approach with those of the posterior approach for patients diagnosed with multilevel cervical myelopathy (MCM).

SUMMARY OF BACKGROUND DATA

Although many studies had compared the outcomes of the anterior approach with that of the posterior approach for MCM in recent years, choosing a proper surgical approach is still a controversial issue .

METHODS

We searched electronic databases for relevant studies that compared the anterior approach with the posterior approach for MCM. Then, data extraction and quality assessment were conducted. We used RevMan 5.3 for data analysis. A random effects model was used for heterogenous data, whereas a fixed-effects model was used for homogenous data.

RESULTS

A total of 25 nonrandomized controlled studies involving 1843 patients were included. No statistical difference was found with regard to the preoperative Japanese Orthopedic Association (JOA) score between the anterior group and the posterior group (P=0.08, 95% CI, -0.02 to 0.40). The postoperative JOA score and the recovery rate were higher in the anterior group as compared with the posterior group (P=0.02, 95% CI, 0.10-1.33; P=0.006, 95% CI, 2.33-13.90). In the subgroup analysis, better postoperative JOA scores and recovery rates were also obtained in the anterior group for cervical spondylotic myelopathy (P=0.0007, 95% CI, 0.29-1.09; P=0.01, 95% CI, 1.30-9.93). No significant differences were found in the complication rate, the revision rate, the operation time, and blood loss between the 2 groups (P=0.17, 95% CI, 0.89-1.95; P=0.21, 95% CI, 0.72-4.61; P=0.31, 95% CI, -20.20 to 63.30; P=0.88, 95% CI, -166.86 to 143.81).

CONCLUSIONS

The anterior approach is associated with a better postoperative neurological outcome compared with the posterior approach in cervical spondylotic myelopathy patients. Considering the complication rate, the revision rate, the operation time, and blood loss, the anterior approach appears to be as safe as the posterior approach. Further randomized controlled trials comparing the anterior approach and the posterior approach for MCM should be performed to make a more convincing conclusion.

Prevalence of complications after surgery in treatment for cervical compressive myelopathy: A meta-analysis for last decade

PURPOSE

We aim to perform a meta-analysis on prevalence of all kinds of operation-related complications following surgery treating cervical compressive myelopathy (CCM) and to provide reference for surgeons making surgical plan.

METHODS

An extensive search of literature was performed in PubMed/MEDLINE, Embase, the Cochrane library, CNKI, and WANFANG databases on incidence of operation-related complications from January 2007 to November 2016. Data was calculated and data analysis was conducted with STATA 12.0 and Revman 5.3.

RESULTS

A total of 107 studies included 1705 of 8612 patients (20.1%, 95% CI 17.3%-22.8%) on overall complications. The incidence of C5 plasy, cerebrospinal fluid (CSF), infection, axial pain, dysphagia, hoarseness, fusion failure, graft subsidence, graft dislodgment, and epidural hematoma is 5.3% (95% CI 4.3%-6.2%), 1.9% (95% CI 1.3%-2.4%), 2.8% (95% CI 1.7%-4.0%), 15.6% (95% CI 11.7%-19.5%), 16.8% (95% CI 13.6%-19.9%), 4.0% (95% CI 2.3%-5.7%), 2.6% (95% CI 0.2%-4.9%), 3.7% (95% CI 2.0%-5.5%), 3.4% (95% CI 2.0%-4.8%), 1.1% (95% CI 0.7%-1.5%), respectively. Patients with ossification of posterior longitudinal ligament (OPLL) (6.3%) had a higher prevalence of C5 plasy than those with cervical spondylotic myelopathy (CSM) (4.1%), and a similar trend in CSF (12.2% vs 0.9%). Individuals after laminectomy and fusion (LF) had highest rate of C5 plasy (15.2%), while those who underwent anterior cervical discectomy and fusion (ACDF) had the lowest prevalence (2.0%). Compared with patients after other surgical options, individuals after anterior cervical corpectomy and fusion (ACCF) have the highest rate of CSF (4.2%), infection (14.2%), and epidural hematoma (3.1%). Patients after ACDF (4.8%) had a higher prevalence of hoarseness than those with ACCF (3.0%), and a similar trend for dysphagia between anterior corpectomy combined with discectomy (ACCDF) and ACCF (16.8% vs 9.9%).

CONCLUSIONS

Based on our meta-analysis, patients with OPLL have a higher incidence of C5 palsy and CSF. Patients after LF have a higher incidence of C5 palsy, ACCDF have a higher incidence of dysphagia, ACCF have a higher incidence of CSF and infection and ACDF have a higher incidence of hoarseness. These figures may be useful in the estimation of the probability of complications following cervical surgery.

Differences in the time of onset of postoperative upper limb palsy among surgical procedures: a meta-analysis

BACKGROUND CONTEXT

The time of onset of postoperative upper limb palsy (ULP), also referred to as C5 palsy, varies among patients. Although some studies addressed the relationship between the time of onset of ULP and the potential etiologies, no meta-analysis has been conducted regarding the association between the time of onset of ULP and other factors such as surgical procedure type and treated diseases.

PURPOSE

This study aimed to elucidate differences in the time of onset of ULP among spinal surgical procedures and treated diseases to understand its etiology.

STUDY DESIGN

This is a meta-analysis.

OUTCOME MEASURES

The time of onset of ULP after cervical decompression surgery.

METHODS

We conducted a meta-analysis via searches of the PubMed, EMBASE, and Cochrane Library databases. Upper limb palsy within 2 days postoperatively or at 3 days or more postoperatively was defined as early- and late-onset, respectively. We calculated the pooled prevalence of early- and late-onset ULP with regard to surgical procedures and diseases using a random effects model. The proportion of early-onset ULP relative to all ULP was also determined. Surgical procedures were categorized into four procedures: (1) anterior cervical discectomy and fusion (ACDF); (2) anterior cervical corpectomy and fusion (ACCF); (3) laminoplasty or laminectomy (LPN); and (4) posterior spinal fusion with decompression (PSF). Treated diseases were classified as ossification of the posterior longitudinal ligament (OPLL) and non-OPLL.

RESULTS

The pooled prevalence of early-onset ULP was significantly stratified across three groups of surgical procedures (PSF [9.0%]>ACCF [3.7%] and LPN [2.5%]>ACDF [0.6%]). In the pooled analysis of late-onset ULP prevalence, three procedures (PSF [4.3%], ACCF [2.8%], and LPN [2.9%]) were similar, but ACDF (1.0%) was associated with a significantly lower prevalence than LPN. The prevalence of both early- and late-onset ULP was significantly higher with OPLL than without OPLL. However, the proportion of early-onset ULP relative to all ULP was similar between non-OPLL and OPLL (50.8% vs. 49.5%).

CONCLUSIONS

The high prevalence of early-onset ULP in PSF is attributable to a lag correction effect, which is triggered by posterior correction and fusion through comparison with LPN. The combination of our meta-analysis results and previous knowledge facilitates our understanding of the etiology of ULP.

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.

Anterior Cervical Spine Surgery for Degenerative Disease: A Review

Anterior cervical spine surgery is an established surgical intervention for cervical degenerative disease and high success rate with excellent long-term outcomes have been reported. However, indications of surgical procedures for certain conditions are still controversial and severe complications to cause neurological dysfunction or deaths may occur. This review is focused mainly on five widely performed procedures by anterior approach for cervical degenerative disease; anterior cervical discectomy, anterior cervical discectomy and fusion, anterior cervical corpectomy and fusion, anterior cervical foraminotomy, and arthroplasty. Indications, procedures, outcomes, and complications of these surgeries are discussed.

Cervical laminoplasty developments and trends, 2003-2013: a systematic review

OBJECT

Despite extensive clinical experience with laminoplasty, the efficacy of the procedure and its advantages over laminectomy remain unclear. Specific clinical elements, such as incidence or progression of kyphosis, incidence of axial neck pain, postoperative cervical range of motion, and incidence of postoperative C-5 palsies, are of concern. The authors sought to comprehensively review the laminoplasty literature over the past 10 years while focusing on these clinical elements.

METHODS

The authors conducted a literature search of articles in the Medline database published between 2003 and 2013, in which the terms "laminoplasty," "laminectomy," and "posterior cervical spine procedures" were used as key words. Included was every single case series in which patient outcomes after a laminoplasty procedure were reported. Excluded were studies that did not report on at least one of the above-mentioned items.

RESULTS

A total of 103 studies, the results of which contained at least 1 of the prespecified outcome variables, were identified. These studies reported 130 patient groups comprising 8949 patients. There were 3 prospective randomized studies, 1 prospective nonrandomized alternating study, 15 prospective nonrandomized data collections, and 84 retrospective reviews. The review revealed a trend for the use of miniplates or hydroxyapatite spacers on the open side in Hirabayashi-type laminoplasty or on the open side in a Kurokawa-type laminoplasty. Japanese Orthopaedic Association (JOA) scoring was reported most commonly; in the 4949 patients for whom a JOA score was reported, there was improvement from a mean (± SD) score of 9.91 (± 1.65) to a score of 13.68 (± 1.05) after a mean follow-up of 44.18 months (± 35.1 months). The mean preoperative and postoperative C2-7 angles (available for 2470 patients) remained stable from 14.17° (± 0.19°) to 13.98° (± 0.19°) of lordosis (average follow-up 39 months). The authors found significantly decreased kyphosis when muscle/posterior element-sparing techniques were used (p = 0.02). The use of hardware in the form of hydroxyapatite spacers or miniplates did not influence the progression of deformity (p = 0.889). An overall mean (calculated from 2390 patients) of 47.3% loss of range of motion was reported. For the studies that used a visual analog scale score (totaling 986 patients), the mean (cohort size-adjusted) postoperative pain level at a mean follow-up of 29 months was 2.78. For the studies that used percentages of patients who complained of postoperative axial neck pain (totaling 1249 patients), the mean patient number-adjusted percentage was 30% at a mean follow-up of 51 months. The authors found that 16% of the studies that were published in the last 10 years reported a C-5 palsy rate of more than 10% (534 patients), 41% of the studies reported a rate of 5%-10% (n = 1006), 23% of the studies reported a rate of 1%-5% (n = 857), and 12.5% reported a rate of 0% (n = 168).

CONCLUSIONS

Laminoplasty remains a valid option for decompression of the spinal cord. An understanding of the importance of the muscle-ligament complex, plus the introduction of hardware, has led to progress in this type of surgery. Reporting of outcome metrics remains variable, which makes comparisons among the techniques difficult.

Is there a difference in range of motion, neck pain, and outcomes in patients with ossification of posterior longitudinal ligament versus those with cervical spondylosis, treated with plated laminoplasty?

OBJECT

There are little data on the effects of plated, or plate-only, open-door laminoplasty on cervical range of motion (ROM), neck pain, and clinical outcomes. The purpose of this study was to compare ROM after a plated laminoplasty in patients with ossification of posterior longitudinal ligament (OPLL) versus those with cervical spondylotic myelopathy (CSM) and to correlate ROM with postoperative neck pain and neurological outcomes.

METHODS

The authors retrospectively compared patients with a diagnosis of cervical stenosis due to either OPLL or CSM who had been treated with plated laminoplasty in the period from 2007 to 2012 at the University of California, San Francisco. Clinical outcomes were measured using the modified Japanese Orthopaedic Association (mJOA) scale and neck visual analog scale (VAS). Radiographic outcomes included assessment of changes in the C2-7 Cobb angle at flexion and extension, ROM at C2-7, and ROM of proximal and distal segments adjacent to the plated lamina.

RESULTS

Sixty patients (40 men and 20 women) with an average age of 63.1 ± 10.9 years were included in the study. Forty-one patients had degenerative CSM and 19 patients had OPLL. The mean follow-up period was 20.9 ± 13.1 months. The mean mJOA score significantly improved in both the CSM and the OPLL groups (12.8 to 14.5, p < 0.01; and 13.2 to 14.2, respectively; p = 0.04). In the CSM group, the mean VAS neck score significantly improved from 4.2 to 2.6 after surgery (p = 0.01), but this improvement did not reach the minimum clinically important difference (MCID). Neither was there significant improvement in the VAS neck score in the OPLL group (3.6 to 3.1, p = 0.17). In the CSM group, ROM at C2-7 significantly decreased from 32.7° before surgery to 24.4° after surgery (p < 0.01). In the OPLL group, ROM at C2-7 significantly decreased from 34.4° to 20.8° (p < 0.01). In the CSM group, the change in the VAS neck score significantly correlated with the change in the flexion angle (r = - 0.31) and the extension angle (r = - 0.37); however, it did not correlate with the change in ROM at C2-7 (r = - 0.1). In the OPLL group, the change in the VAS neck score did not correlate with the change in the flexion angle (r = 0.03), the extension angle (r = - 0.17), or the ROM at C2-7 (r = - 0.28). The OPLL group had a significantly greater loss of ROM after surgery than did the CSM group (p = 0.04). There was no significant correlation between the change in ROM and the mJOA score in either group.

CONCLUSIONS

Plated laminoplasty in patients with either OPLL or CSM decreases cervical ROM, especially in the extension angle. Among patients who have undergone laminoplasty, those with OPLL lose more ROM than do those with CSM. No correlation was observed between neck pain and ROM in either group. Neither group had a change in neck pain that reached the MCID following laminoplasty. Both groups improved in neurological function and outcomes.

Intraoperative neuromonitoring with MEPs and prediction of postoperative neurological deficits in patients undergoing surgery for cervical and cervicothoracic myelopathy

OBJECT

The use of intraoperative neurophysiological monitoring (IONM) in surgical decompression surgery for myelopathy may assist the surgeon in taking corrective measures to reduce or prevent permanent neurological deficits. We evaluated the efficacy of IONM in cervical and cervicothoracic spondylotic myelopathy (CSM) cases.

METHODS

The authors retrospectively reviewed 140 cases involving patients who underwent surgery for CSM utilizing IONM during 2011 at the University of California, San Francisco. Data on preoperative clinical variables, intraoperative changes in transcranial motor evoked potentials (MEPs), and postoperative new neurological deficits were collected. Associations between categorical variables were analyzed with the Fisher exact test.

RESULTS

Of the 140 patients, 16 (11%) had significant intraoperative decreases in MEPs. In 8 of these cases, the MEP signal did not return to baseline values by the end of the operation. There were 8 (6%) postoperative deficits, of which 6 were C-5 palsies and 2 were paraparesis. Six of the patients with postoperative deficits had demonstrated persistent MEP signal change on IONM. There was a significant association between persistent MEP changes and postoperative deficits (p < 0.001). The sensitivity of intraoperative MEP monitoring was 75%, the specificity 98%, the positive predictive value 75%, and the negative predictive value 98%. Due to higher rates of false negatives, the sensitivity decreased to 60% in the subgroup of patients with vascular disease comorbidity. The sensitivity increased to 100% in elderly patients and in patients with preoperative motor deficits. The sensitivity and positive predictive value of deltoid and biceps MEP changes in predicting C-5 palsy were 67% and 67%, respectively.

CONCLUSIONS

The authors found a correlation between decreased intraoperative MEPs and postoperative new neurological deficits in patients with CSM. Sensitivity varies based on patient comorbidities, age, and preoperative neurological function. Monitoring of MEPs is a useful adjunct for CSM cases, and the authors have developed a checklist to standardize their responses to intraoperative MEP changes.

Anterior corpectomy versus posterior laminoplasty for multilevel cervical myelopathy: a systematic review and meta-analysis

BACKGROUND

Surgical strategy for multilevel cervical myelopathy resulting from cervical spondylotic myelopathy (CSM) or ossification of posterior longitudinal ligament (OPLL) still remains controversial. There are still questions about the relative benefit and safety of direct decompression by anterior corpectomy (CORP) versus indirect decompression by posterior laminoplasty (LAMP).

OBJECTIVE

To perform a systematic review and meta-analysis evaluating the results of anterior CORP compared with posterior LAMP for patients with multilevel cervical myelopathy.

METHODS

Systematic review and meta-analysis of cohort studies comparing anterior CORP with posterior LAMP for the treatment of multilevel cervical myelopathy due to CSM or OPLL from 1990 to December 2012. An extensive search of literature was performed in Pubmed, Embase, and the Cochrane library. The quality of the studies was assessed according to GRADE. The following outcome measures were extracted: pre- and postoperative Japanese orthopedic association (JOA) score, neurological recovery rate (RR), surgical complications, reoperation rate, operation time and blood loss. Two reviewers independently assessed each study for quality and extracted data. Subgroup analysis was conducted according to the mean number of surgical segments.

RESULTS

A total of 12 studies were included in this review, all of which were prospective or retrospective cohort studies with relatively low quality. The results indicated that the mean JOA score system for cervical myelopathy and the neurological RR in the CORP group were superior to those in the LAMP group when the mean surgical segments were <3, but were similar between the two groups in the case of the mean surgical segments equal to 3 or more. There was no statistical difference in the surgical complication rate between the two groups when the mean surgical segments <3, but were significantly higher incidences of surgical complications and complication-related reoperation in the CORP group compared with the LAMP group in the case of the mean surgical segments equal to 3 or more. Besides, the operation time in the CORP group was longer than that in the LAMP group, and the average blood loss was significantly more in the CORP group compared with the LAMP group.

CONCLUSION

Based on the results above, anterior CORP and fusion is recommended for the treatment of multilevel cervical myelopathy when the involved surgical segments were <3. Given the higher rates of surgical complications and complication-related reoperation and the higher surgical trauma associated with multilevel CORP, however, it is suggested that posterior LAMP may be the preferred method of treatment for multilevel cervical myelopathy when the involved surgical segments were equal to 3 or more. In addition, taking the limitations of this study into consideration, it was still not appropriate to draw a strong conclusion claiming superiority for CORP or LAMP. A well-designed, prospective, randomized controlled trial is necessary to provide objective data on the clinical results of both procedures.