Outcomes of surgical intervention for cervical spondylotic myelopathy accompanying local kyphosis (comparison between laminoplasty alone and posterior reconstruction surgery using the screw-rod system)

Deformity Considerations in Cervical Laminoplasty: A Narrative Review

OBJECTIVES

We discuss the incidence of postoperative kyphosis following laminoplasty and its impact on outcomes, as well as critical radiographic parameters, intraoperative technical factors, and postoperative protocols that can be used to improve results.

SUMMARY OF BACKGROUND DATA

When appropriately selected, cervical laminoplasty is a motion-sparing treatment option for cervical myelopathy and is a valid alternative to laminectomy and fusion procedures. However, like other posterior-based cervical decompression techniques, laminoplasty can cause postoperative kyphosis.

METHODS

A PubMed search was performed to gather articles that focus on cervical deformity in the context of cervical laminoplasty.

RESULTS

The reported conversion rates of lordotic to kyphotic cervical alignment after laminoplasty range from 5.2% to 11.3%. Kyphosis likely reduces the benefit from the operation as measured by postoperative mJOA scores. A surgeon can minimize the risk of causing a clinically significant reduction in lordosis by screening out patients with certain radiographic characteristics. Intraoperative decisions such as dissection techniques, levels chosen, and hybrid constructs can preserve the cervical tension band. Certain postoperative protocols can improve cervical posture.

CONCLUSIONS

Cervical laminoplasty is an effective tool for treating degenerative cervical myelopathy. Careful radiographic screening, intraoperative decision-making, and postoperative protocols can minimize the development of postoperative cervical deformity and improve outcomes.

LEVEL OF EVIDENCE

Level V.

Current Concepts of Cervical Spine Alignment, Sagittal Deformity, and Cervical Spine Surgery

There are not many reports on cervical spine alignment, and only a few analyze ideal surgical approaches and optimal amounts of correction needed for the various types of deformity. We comprehensively reviewed the present literature on cervical spinal deformities (with or without myelopathy) and their surgical management to provide a framework for surgical planning. A general assessment of the parameters actually in use and correlations between cervical and thoracolumbar spine alignment are provided. We also analyzed posterior, anterior, and combined cervical surgical approaches and indications for the associated techniques of laminoplasty, laminectomy and fusion, and anterior cervical discectomy and fusion. Finally, on the basis of the NDI, SF-36, VAS, and mJOA questionnaires, we fully evaluated the outcomes and measures of postoperative health-related quality of life. We found the need for additional prospective studies to further enhance our understanding of the importance of cervical alignment when assessing and treating cervical deformities with or without myelopathy. Future studies need to focus on correlations between cervical alignment parameters, disability scores, and myelopathy outcomes. Through this comprehensive literature review, we offer guidance on practical and important points of surgical technique, cervical alignment, and goals surgeons can meet to improve symptoms in all patients.

Favorable cervical extension capacity preventing loss of cervical lordosis after laminoplasty due to spontaneous restoration of initial lordosis

BACKGROUND CONTEXT

Cervical laminoplasty is a common approach for the treatment of multilevel cervical spondylotic myelopathy (CSM). Postoperative loss of cervical lordosis (LCL) was associated with lower extension motion of the cervical spine before laminoplasty.

PURPOSE

To analyze the possible causes of preoperative cervical extension capacity affecting LCL after laminoplasty by evaluating the changes in cervical lordosis (CL) at different stages.

STUDY DESIGN/SETTING

Retrospective study.

PATIENT SAMPLE

Seventy-two patients undergoing laminoplasty due to multilevel CSM.

OUTCOME MEASURES

Radiographic parameters included CL, extension CL (eCL), flexion CL (fCL), range of motion (ROM), extension ROM (eROM), flexion ROM (fROM) and LCL. Clinical outcomes were assessed using the Japanese Orthopedic Association (JOA) and neck disability index (NDI) score.

METHODS

The data were recorded before surgery and at 3- and 24-month follow-up. All patients completed a cervical extension test preoperatively. A receiver operating characteristic (ROC) curve of eROM was constructed to discriminate the patients with and without postoperative kyphotic deformity.

RESULTS

According to the optimal cut-off value of eROM, the patients were divided into two groups: extension group (eROM≥9.3°) and control group (eROM<9.3°). The radiographic outcomes demonstrated no significant differences in CL, eCL, fCL and ROM between the two groups. Both eROM and fROM were significantly different in the two groups. There was a significant change in CL in the extension group at 3-month follow-up and in the control group at 24-month follow-up. The extension group exhibited significantly lower LCL compared with the control group at follow-up. No significant difference between the two groups was noted in the JOA recovery rate, while the NDI score was significantly different at 24-month follow-up. The positivity ratio of the extension test was significantly greater in the extension group than that in the control group.

CONCLUSIONS

eROM in patients with favorable preoperative cervical extension capacity (eROM≥9.3°) consisted of the actual extension capacity and compensatory flexion. The cervical alignment would be spontaneously restored to its initial lordosis in the short term after laminoplasty. These patients had no substantial LCL at 24-month follow-up and would be good candidates for laminoplasty.

Surgical Technique of Central and Over-the-Top Full-Endoscopic Decompression of the Cervical Spine: A Technical Note

Endoscopic surgery of the cervical spine is constantly evolving and the spectrum of its indications has expanded in recent decades. Full-endoscopic techniques have standardized the procedures for posterior and anterior access. The full-endoscopic approach was developed to treat degenerative diseases with the least possible invasion and without causing instability of the cervical spine. The posterior full-endoscopic approach is indicated for the treatment of diseases of the lateral part of the vertebral segment, such as herniations and stenoses of the lateral recess and vertebral foramen. There has been little discussion of this approach to the treatment of central stenosis of the cervical spine. This technical note describes a step-by-step surgical technique for central and over-the-top full-endoscopic decompression in the cervical spine, using a 3.7 mm working channel endoscope. This technique has already been shown to be effective in a recent case series with a 4.7 mm working channel endoscope, and may represent a new treatment option for central or bilateral lateral recess stenosis. There is also the possibility of a bilateral full-endoscopic approach, but this may be associated with greater muscle damage and a longer operative time. Case series and comparative studies should be encouraged to confirm the safety and utility of this technique.

Surgical Outcomes of Selective Laminectomy for Patients With Cervical Kyphosis: A Retrospective Study of 379 Cases

STUDY DESIGN

A retrospective study.

OBJECTIVES

This study aimed to investigate the impact of cervical kyphosis on patients with cervical spondylotic myelopathy (CSM) following selective laminectomy (SL) regarding posterior spinal cord shift (PSS), and a number of SLs.

METHODS

We evaluated 379 patients with CSM after SL. The patients with kyphosis (group K) were compared with those without kyphosis (group L). Moreover, groups K and L were divided into subgroups KS and KL (SLs ≤ 2) and LS and LL (SLs ≥ 3), respectively, and analyzed. Receiver operating characteristic (ROC) curve analysis was performed to determine the cut-off value of the C2-C7 angle for satisfactory surgical outcomes, which was defined as a Japanese Orthopaedic Association (JOA) recovery rate of ≥50% in group KS.

RESULTS

The average PSS (mm) in group K was smaller than that in group L (.8 vs 1.4; P < .01), but the JOA recovery rate was comparable between the 2 groups. Meanwhile, the mean PSS and JOA recovery rate (%) in group KS was lower than those in group KL, respectively (.3 vs 1.0; P < .01, 35.1 vs 52.3; P = .047). Moreover, the average PSS of group KS (.6) was smaller than those of other subgroups ( < .01). In addition, the ROC curve analysis showed that the C2-C7 angle of -14.5° could predict satisfactory surgical outcomes in group KS.

CONCLUSION

Selective laminectomy is not contraindicated for patients with kyphosis, but a larger number of SLs may be indicated for the patients with C2-C7 angles of ≤ -14.5°.

Clinical outcomes of modified versus traditional expansive open-door laminoplasty for cervical spondylotic myelopathy: A single-institution experience

PURPOSE

To compare the surgical outcomes of modified expansive open-door laminoplasty (EOL) (C4-C6) and traditional EOL (C3-C7) in patients with cervical spondylotic myelopathy (CSM).

METHODS

One hundred and two CSM patients were retrospectively recruited from Fujian Medical University Union Hospital between March 2012 and December 2019. Seventy-one patients with CSM underwent modified EOL, and 31 patients underwent traditional EOL. The primary endpoint was axial symptoms.

RESULTS

Patients who underwent modified EOL had a significantly lower incidence of axial symptoms (odds ratio: 0.273; 95% confidence interval: 0.184-0.691; p = .002). The length of hospital stay (p = .263), and intraoperative blood loss (p = .402) were not significantly different between the groups. Significantly more postoperative drainage was observed in patients who underwent modified EOL (p < .001), while the cost of hospitalization in patients treated with traditional EOL was higher (p = .011). There were significant differences between modified and traditional EOL for the changes in range of motion (p < .001), modified Japanese Orthopaedic Association score (p = .001), and the Nurick grade (p = .014), while the changes of visual analogue scale (p = .250), and the neck disability index (p = .134) were not significantly different between the groups.

CONCLUSION

This study found modified EOL may decrease the incidence of axial symptoms in patients with CSM compared to traditional EOL.

Full Endoscopic Spine Surgery for Cervical Spondylotic Myelopathy: A Systematic Review

BACKGROUND

Cervical spondylotic myelopathy (CSM) may seriously affect quality of life. In the literature, there is scarce evidence of the pros and cons of full endoscopic spine surgery in the treatment of CSM. The main purpose of this study was to conduct a systematic review to elucidate the efficacy of full endoscopic spine surgery in the management of patients with CSM.

METHODS

This systematic review was conducted in accordance with the PRISMA guidelines. A systematic search of Web of Science, PubMed MEDLINE, Embase, and Cochrane Library was conducted from the database inception to February 1, 2023.

RESULTS

The study included 183 patients and their age was 56.78 ± 7.87 years. The average surgical time calculated was 96.34 ± 33.58 minutes. Intraoperative blood loss ranged from a minimal amount to 51 mL. The average duration of hospital stay was 3.56 ± 1.6 days. The average span for follow-up was on an interval of 18.7 ± 6.76 months. Significant improvements were noted in all aspects of functional outcomes and image results after full endoscopic cervical spine surgery, with no major complications.

CONCLUSIONS

The current study found that both anterior transcorporeal and posterior surgical approaches could be used for the treatment of CSM with a full endoscopic technique. Indications of full endoscopic cervical spine surgery for CSM included cervical disc herniation, central canal stenosis, calcified ligamentum flavum, and ossification of the posterior longitudinal ligament. Improved postoperative outcomes with acceptable surgical complications were noted in this systematic review.

Posterior Preventive Foraminotomy before Laminectomy Combined with Pedicle Screw Fixation May Decrease the Incidence of C5 Palsy in Complex Cervical Spine Surgery in Patients with Severe Myeloradiculopathy

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

Usefulness of K-line in predicting prognosis of laminoplasty for cervical spondylotic myelopathy

BACKGROUND

K-line is widely recognized as a useful index for evaluating cervical alignment and the size of the cervical ossification at the posterior longitudinal ligament (OPLL). The purpose of this study was to investigate whether the K-line could be a useful clinical tool for predicting the prognosis of laminoplasty (LP) for cervical spondylotic myelopathy (CSM).

METHODS

Adult CSM patients scheduled for cervical LP were recruited for this study. C2-7 angle, local kyphosis angle, and K-line was evaluated by T2-weighted sagittal magnetic resonance imaging (MRI). Clinical findings were evaluated by the JOA score and the recovery rate. Clinical and radiological findings were evaluated preoperation and final follow-up. Patients were grouped into K-line ( +) and K-line (-). Patients with Kline (-) were further divided into two sub-groups: disc type (anterior cord compression due to disc protrusion with kyphosis) and osseous type (due to osseous structure such as osteophyte).

RESULTS

Sixty-eight patients were included in the analysis. The recovery rate of K-line (-) group (n = 11,19.4%) was significantly worse than that of K-line ( +) group (n = 57, 50.6%, p<0.05). Among 11 K-line (-) patients, 7 were disc type and 4 were osseous type. Over the period of follow-up, the disc type K-line (-) patients changed to K-line ( +) and showed significantly better recovery rate (27.6%) compared to the osseous type K-line (-) group (5.0%, p < 0.05).

CONCLUSION

The present of this study indicate that K-line may have a predictive value for clinical outcome in patients undergoing LP for CSM. K-line (-) of osseous type was worse than k-line (-) of disc type.

Biomechanical effects of hybrid constructions in the treatment of noncontinuous cervical spondylopathy: a finite element analysis

BACKGROUND

Hybrid construction (HC) may be an ideal surgical strategy than noncontinuous total disc replacement (TDR) and noncontinuous anterior cervical discectomy and fusion (ACDF) in the treatment of noncontinuous cervical spondylopathy. However, there is still no consensus on the segmental selection for ACDF or TDR in HC. The study aims to analyse the effects of different segment selection of TDR and ACDF on cervical biomechanical characteristics after HC surgery.

METHODS

Twelve FEMs of C2-C7 were constructed based on CT images of 12 mild cervical spondylopathy volunteers. Two kinds of HC were introduced in our study: Fusion-arthroplasty group (Group 1), upper-level (C3/4) ACDF, and lower-level TDR (C5/6); Arthroplasty-fusion group (Group 2), upper-level (C3/4) TDR and lower-level ACDF (C5/6). The follow-load technique was simulated by applying an axial initial load of 73.6 N through the motion centre of FEM. A bending moment of 1.0 Nm was applied to the centre of C2 in all FEMs. Statistical analysis was carried out by SPSS 26.0. The significance threshold was 5% (P < 0.05).

RESULTS

In the comparison of ROMs between Group 1 and Group 2, the ROM in extension (P = 0.016), and lateral bending (P = 0.038) of C4/5 were significantly higher in Group 1 group. The average intervertebral disc pressures at C2/3 in all directions were significantly higher in Group 1 than those in Group 2 (P < 0.005). The average contact forces in facet joints of C2/3 (P = 0.007) were significantly more than that in Group 2; however, the average contact forces in facet joints of C6/7 (P < 0.001) in Group 1 group were significantly less than that in Group 2.

CONCLUSIONS

Arthroplasty-fusion is preferred for intervertebral disc degeneration in adjacent upper segments. Fusion-arthroplasty is preferred for patients with lower intervertebral disc degeneration or lower posterior column degeneration.

TRIAL REGISTRATION

This research was registered in Chinese Clinical Trial Registry (ChiCTR1900020513).

Cervical single open-door laminoplasty with or without local lateral mass screw fixation and fusion to treat cervical spinal cord injuries accompanied by segmental spinal canal stenosis

Study Design

Retrospective.

Objectives

To investigate the efficacy of cervical single open-door laminoplasty with and without local lateral mass screw fixation and fusion as treatments for cervical spinal cord injuries accompanied by multisegmental spinal canal stenosis.

Setting

The Second Affiliated Hospital, School of Medicine, Zhejiang University.

Methods

Of all enrolled patients, 42 formed a stable group who underwent cervical single open-door laminoplasty alone and 14 formed an unstable group who underwent the procedure combined with lateral mass screw fixation and fusion. Neurological function was evaluated before surgery, at discharge, and at final follow-up using the American Spinal Cord Injury Association (ASIA) impairment scale and the Japanese Orthopedic Association (JOA) score.

Results

ASIA scores reflected improved neurological function in 52.5% of the stable group (15 with grade-D and 4 with grade-A injuries did not improve) and 45.5% of the unstable group (3 with grade-D and 3 with grade-A injuries did not improve). Postoperative JOA scores reflected 19.1% ± 21.6% improvement in the stable group and 18.6% ± 18.4% improvement in the unstable group (P > 0.05). Final follow-up JOA scores reflected 49.2% ± 31.7% improvement in the stable group and 47.1% ± 39.2% improvement in the unstable group (P > 0.05).

Conclusions

Laminoplasty combined with local fusion aided the treatment of unstable cervical spinal cord injuries and spinal stenosis. Such stenosis is the main pathological factor causing multiple spinal cord compressions in patients with cervical spinal cord injuries.

A comparative study of surgical outcomes between anterior cervical discectomy with fusion and selective laminoplasty for cervical spondylotic myelopathy

BACKGROUND

Few studies have directly compared anterior and posterior surgical approaches in cervical spondylotic myelopathy (CSM) patients with short-segment disease. We aimed to examine and compare surgical outcomes of anterior cervical discectomy with fusion (ACDF) and selective laminoplasty (S-LAMP) in CSM patients with 1- or 2-level disease.

METHODS

Forty-six patients, who received surgeries for CSM, were prospectively investigated; 24 underwent ACDF and 22 underwent S-LAMP. Average follow-up was 3.5 years. The following pre- and postoperative radiographic measurements were recorded: (1) C2-7 angle, (2) local angle (lordotic Cobb angle at operative level), (3) cervical sagittal vertical axis (SVA) (center of gravity of the head-C7 SVA), and (4) C7 slope. Outcomes were evaluated using the Japanese Orthopedic Association scoring system for cervical myelopathy (C-JOA score), neck pain visual analog scale, and neck disability index (NDI).

RESULTS

There were no significant differences in patient demographics between the two groups. Postoperatively, C2-7 angle, local angle, cervical SVA, C7 slope, C-JOA score, and neck pain and NDI scores were not significantly different between the two groups; however, the recovery rate of the C-JOA score was superior in the ACDF group (57.5%) compared to the S-LAMP group (42.1%). The recovery rate of the C-JOA score in the local lordosis subgroup (local angle ≥ 0°) showed no significant difference between the two surgical groups. However, in the local kyphosis subgroup (local angle < 0°), C-JOA score recovery rate was worse after S-LAMP (20.4%) than ACDF (57.9%); local angle also worsened postoperatively after S-LAMP.

CONCLUSIONS

In patients with local lordosis at the segments of cervical spondylosis and spinal cord compression, S-LAMP showed equivalent surgical outcomes (neurological recovery, neck pain and NDI scores, and cervical alignment) to ACDF. However, in patients with local kyphosis, S-LAMP worsened the kyphosis and resulted in worse neurological recovery.

Comparison of Two Anterior Reconstructive Techniques in the Treatment of 3-Level and 4 Level Cervical Spondylotic Myelopathy: A Meta-analysis of Last Decade

Study Design

A meta-analysis.

Objective

Anterior cervical discectomy and fusion (ACDF) and anterior cervical corpectomy and fusion (ACCF) are widely used in the treatment of cervical spondylotic myelopathy (CSM). However, the clinical outcomes and complications between ACDF and ACCF treating multi-level CSM remain poorly understood. Thus, we performed a meta-analysis to compare the clinical outcomes and complications of the two procedures in the treatment of 3-level and 4-level CSM.

Methods

An extensive search of the literature was performed in the English databases of PubMed, Embase, and Cochrane Library and the Chinese databases of CNKI and WANFANG. We collected factors, including demographic data, surgical factors, and complications. Data analysis was conducted with RevMan 5.3 and STATA 12.0.

Results

Finally, 14 articles (5429 patients) were included in our study. No significant difference was found in preoperative and 3-month follow-up Japanese Orthopedic Association (JOA) scores, neck disability index, preoperative C2-C7, segmental angle, operation time, as well as the number of dysphagia, hoarseness, cerebral fluid leakage, infection, epidural hematoma, axial pain, hardware breakage, and pseudarthrosis between ACDF and ACCF. However, our findings showed that blood loss (P < 0.00001), the number of total complications (P < 0 .00001), C5 palsy (P = 0.0004), graft dislodgement (P = 0.02), graft subsidence (P = 0.0003), and revision surgery (P = 0.0008) in ACDF were significantly less than in ACCF. Additionally, postoperative and change of C2-C7 (P < 0.00001), segment angle (P < 0.00001), and fusion rate (P = 0.001) in ACDF were significantly higher than in ACCF. Post-operative JOA in ACDF was significantly higher than in ACCF (P = 0.02).

Conclusions

Although the clinical efficacy of both surgeries was similar, ACDF was superior to ACCF in the reconstruction of cervical lordosis and the number of complications in the treatment of 3-level and 4-level CSM.

The cervical sagittal curvature change in patients with or without PCSM after laminoplasty

Objective

After laminoplasty, the cervical sagittal curvature of some patients tend to be lordotic, this phenomenon cannot be explained by the theory of laminoplasty, and the reason remains unknown. We explored the possible role played by pinching cervical spondylotic myelopathy (PCSM) in the cervical sagittal curvature change in patients after laminoplasty.

Methods

From April 2017 to May 2019, we studied 122 patients undergoing laminoplasty with cervical spondylotic myelopathy (CSM). All patients were divided into Group A (anterior compression only, without PCSM) and Group B (both anterior and posterior compression, with PCSM). The visual analogue scale (VAS) was used to measure pain, and modified Japanese Orthopedic Association (mJOA) score was derived. The cervical global angle (CGA) and the range of cervical motion (ROM) were compared. The clinical and imaging results were compared between Group A and Group B.

Results

After laminoplasty, both the mean VAS and mJOA scores improved significantly in Group A and Group B, the mJOA recovery rate of Group B was better than that of Group A (P < 0.05). The mean CGA and ROM decreased in Group A, but increased in Group B. MRI revealed that the ligamentum flavum of Group A was significantly thinner than that of Group B (P < 0.05).

Conclusions

Because of the hypertrophic and folded ligamentum flavum compressing the dorsal spinal cord, patients with PCSM may maintain a compulsive kyphotic posture. After laminoplasty, the cervical sagittal curvature of these patients tend to be lordotic due to the release of dorsal spinal cord compression.

Comparison of Complications between Anterior Cervical Diskectomy and Fusion versus Anterior Cervical Corpectomy and Fusion in Two- and Three-Level Cervical Spondylotic Myelopathy: A Meta-analysis

BACKGROUND

 In this study, we systematically analyze the differences in complications between anterior cervical diskectomy and fusion (ACDF) and anterior cervical corpectomy and fusion (ACCF) in two- and three-level cervical spondylotic myelopathy (CSM).

METHODS

 We performed a systematic search in MEDLINE, EMBASE, PubMed, Web of Science, Cochrane databases, Chinese Biomedical Literature Database, CNKI, and Wan Fang Data for all relevant studies. All statistical analyses were performed using Review Manager version 5.3.

RESULTS

 A total of 11 articles with 849 study subjects were included, with 474 patients in the ACDF group and 375 patients in the ACCF group. The results of the meta-analysis showed that in C5 palsy (odds ratio [OR]: 0.41; 95% confidence interval [CI]: 0.16-1.06), pseudarthrosis (OR: 1.07; 95% CI: 0.23-5.07), dysphagia (OR: 1.06; 95% CI: 0.60-1.86), infection (OR: 0.41; 95% CI: 0.16-1.09), cerebrospinal fluid leakage (OR: 1.21; 95% CI: 0.39-3.73), graft dislodgment (OR: 0.28; 95% CI: 0.06-1.37), and hematoma (OR: 0.32; 95% CI: 0.06-1.83), there are no significant differences between the ACDF and ACCF groups, whereas total complication (OR: 0.50; 95% CI: 0.31-0.80) showed that the ACDF group had a significantly lower morbidity than the ACCF group. Furthermore, the three-level subgroup of ACDF had significantly better results in C5 palsy (OR: 0.31; 95% CI: 0.11-0.88), infection (OR: 0.22; 95% CI: 0.05-0.94), graft dislodgment (OR: 0.07; 95% CI: 0.01-0.40), and total complication (OR: 0.37; 95% CI: 0.23-0.60) compared with the ACCF subgroup.

CONCLUSION

 In general, postoperative pseudarthrosis, dysphagia, cerebrospinal fluid leakage, hematoma, C5 palsy, infection, and graft dislodgment did not differ significantly between the two groups. Total complication was significantly less in the ACDF group compared to the ACCF group. In the three-level subgroup, the morbidity of C5 palsy, infection, and graft dislodgment was significantly lower in ACDF than in ACCF.

Clinical Efficacy of Posterior Percutaneous Endoscopic Unilateral Laminotomy with Bilateral Decompression for Symptomatic Cervical Spondylotic Myelopathy

Objective

To compare the clinical efficacy of posterior percutaneous endoscopic unilateral laminotomy (PPEUL) and anterior cervical decompression and fusion (ACDF) in the treatment of single‐segment spondylotic myelopathy (CSM).

Methods

This is a retrospective research, from January 2017 to December 2019, 30 cases were included in the PPEUL group and 32 cases were included in the ACDF group. The operative duration, blood loss, length of stay, complications, Japanese Orthopaedic Association (JOA) score, visual analogue scale (VAS) score, MacNab classification and imaging data were collected preoperatively, postoperative 1‐week, final follow‐up and statistically analyzed.

Results

The surgery was completed successfully on all patients, and there were no serious complications, such as nerve or spinal cord injury or infection. In the PPEUL and ACDF groups, the operative duration were 56.63 ± 1.40 and 65.21 ± 2.45 min, the intraoperative blood loss were 51.69 ± 3.23 and 50.51 ± 5.48 mL, and the hospitalization duration was 5.75 ± 1.43 and 6.38 ± 2.16 days. The follow‐up period in the PPEUL and ACDF groups was 24.96 ± 1.12 months and 25.65 ± 1.45 months, respectively. There was no significant difference in intraoperative blood loss between the two groups, but the hospitalization and operative durations in the PPEUL group were significantly shorter than those in the ACDF group (P < 0.05). The VAS scores at postoperative 1 week and final follow‐up were significantly improved compared with those before surgery. The JOA scores at postoperative 1 week and final follow‐up were significantly improved compared with those before surgery, but there was no significant difference between the two groups at the last follow‐up. The intervertebral disc height of the adjacent segment at the last follow‐up was significantly lower in the ACDF group than in the PPEUL group (P < 0.05), but there was no significant difference between the two groups in the intervertebral disc height of the surgical segment (P > 0.05). The rate of excellent and good results was 90.0% and 87.5%, respectively. Postoperative cervical CT and MRI showed that the spinal canal was fully decompressed and spinal cord compression was relieved.

Conclusion

PPEUL has the advantages of reduced trauma, rapid recovery and remarkable curative efficacy, so it is a new choice for the treatment of CSM.

Accuracy of pedicle screw placement using patient-specific template guide system

BACKGROUND

Despite repeated efforts for accurate cervical pedicle screw insertion, malpositioning of the inserted screw is commonly noted. To avoid neurovascular complications during cervical pedicle screw insertion, we have developed a new patient-specific screw guide system. This study aimed to evaluate the accuracy of cervical PS placement using the new patient-specific screw guide system.

METHODS

This study is a retrospective clinical evaluation of prospectively enrolled patients. Seventeen consecutively enrolled patients who underwent posterior cervical fusion using the guide system were included. Firstly, three-dimensional planning of pedicle screw placement was done using simulation software. A screw guide for each vertebra was constructed preoperatively. A total of 77 screws were inserted with the guides. Postoperative computed tomography was used to evaluate pedicle perforation, and screw deviations, between the planned and actual screw positions, were measured.

RESULTS

A total of 76 screws (98.7%) were completely inside the pedicle (C3-7), without neurovascular injuries. The mean screw deviations from the planned trajectory at the narrowest point of the pedicle and at the entry point in the axial and sagittal planes were 0.56 ± 0.43 mm and 0.43 ± 0.35 mm and 0.43 ± 0.30 mm and 0.63 ± 0.50 mm, respectively. There were no significant differences in any parameter at different spinal levels. Angular deviations in the sagittal and axial planes were 2.94 ± 2.04° and 2.53 ± 1.85°, respectively. Sagittal angular deviations tended to increase in the cranial vertebra (C3 and C4) compared to the middle cervical spine.

CONCLUSIONS

We demonstrated that our patient-specific screw guide is vital for guiding precise screw insertion in the cervical pedicle. This technique may be an effective solution for achieving precise screw insertion and reducing the incidence of complications.

Surgical and Functional Outcomes of Expansive Open-Door Laminoplasty for Patients With Mild Kyphotic Cervical Alignment

Objective

To evaluate the cervical dynamics, neurological function, pain, and quality of life in patients with mild cervical kyphotic alignment who underwent expansive unilateral open-door laminoplasty (ELAP).

Methods

In this retrospective single-center study, we reviewed the surgical outcomes of 80 patients with cervical spondylotic myelopathy who were followed for at least 2 years. The patients were categorized into the preoperative kyphotic group (C2–7 angle < 0°) and nonkyphotic group (angle ≥ 0°). We compared clinical information, radiographic parameters, Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ) scores, and cervical Japanese Orthopaedic Association (JOA) scores between the groups.

Results

The kyphotic and nonkyphotic groups comprised 17 and 63 patients, respectively. The preoperative C2–7 angles were -3.7° in the kyphotic group and 15.4° in the nonkyphotic group (p<0.01). In the kyphotic group, kyphotic alignment improved to lordosis at the final follow-up (2.6°, p=0.01). The preoperative (16.4° vs. 24.1°, p<0.01) and final-follow-up (17.8° vs. 24.5°, p<0.01) C7 slopes were significantly smaller in the kyphotic group. ELAP reduced pain in the arms or hands (p=0.02) and improved the JOA scores (p<0.01) in the kyphotic group. Patient-reported outcomes assessed using the JOACMEQ showed comparable effective rates in both groups.

Conclusion

Patients with mild cervical kyphosis showed smaller C7 slopes as a compensatory mechanism. Kyphotic angles significantly improved to lordosis after ELAP, resulting in favorable clinical outcomes. ELAP is a useful surgical option for patients even if they present mild kyphotic cervical angles.

Comparative Effectiveness and Safety of Open-Door Laminoplasty, French-Door Laminoplasty, Laminectomy and Fusion, and Laminectomy Alone for Multilevel Degenerative Cervical Myelopathy: A Bayesian Network Analysis

OBJECTIVES

To evaluate the comparative effectiveness and safety of open-door laminoplasty (OLP), French-door laminoplasty (FLP), laminectomy and fusion (LF), and laminectomy alone (LA) in treating multilevel degenerative cervical myelopathy (MDCM).

METHODS

Embase, PubMed, and Cochrane library were searched from their inception date to 7 January 2021. Randomized controlled trials and cohort studies comparing OLP, FLP, LF, and LA were identified to perform a network meta-analysis (NMA).

RESULTS

A total of 30 studies with 2671 patients were included. Our NMA results showed no significant difference between LF and OLP, but both are superior to LA and FLP in the comparison of JOA (Japanese Orthopaedic Association) score improvement. LF showed a most unsatisfactory outcome in postoperative range of motion (ROM) compared with LA or OLP or with FLP. For the complication outcome, no significant differences were found. The surface under the cumulative ranking curves (SUCRA) for JOA improvement was as follows: LF, OPL, LA, and FLP. For ROM reduction it was LA, OPL, FPL, and LF. For complications it was LF, LA, OLP, and FLP.

CONCLUSIONS

Considering all the evaluated criteria, none of the procedures showed the best outcome with least complications and optimal efficacy. However, OLP can be most recommended because of its second-ranking spectra in both of JOA improvement and ROM reduction, also with an acceptable incidence of complications, with the third least.

Cervical alignment in the obese population following posterior cervical fusion for cervical myelopathy

STUDY DESIGN

Retrospective cohort study OBJECTIVE: The aim of this study was to investigate the effect of body mass index (BMI) on the reoperation rate and cervical sagittal alignment of patients who underwent posterior cervical decompression and fusion for cervical spondylotic myelopathy (CSM).

SUMMARY OF BACKGROUND DATA

Cervical sagittal balance has been correlated with postoperative clinical outcomes. Previous studies have shown worse postoperative sagittal alignment and higher reoperation rates in patients with high BMI undergoing anterior decompression and fusion. Similar evidence for the impact of obesity in postoperative sagittal alignment for patients with (CSM) undergoing posterior cervical decompression and fusion (PCF) is lacking.

METHODS

A retrospective analysis of 198 patients who underwent PCF for cervical myelopathy due to degenerative spine disease was performed. Demographics, need for reoperation, and perioperative radiographic parameters were collected. Cervical lordosis (CL), C2-7 sagittal vertical axis (SVA), and T1 slope (T1S) was measured on standing lateral radiographs. Comparative analysis of the patient cohort was performed by stratifying the sample population into three BMI categories (<25, 25-30, ≥30).

RESULT

Of the 198 patients that met inclusion criteria, 53 had BMI normal (<25), 65 were overweight (25-30), and 80 were obese (≥30). Mean SVA increased postoperatively in all groups, 4 mm in the normal group, 13 mm in the overweight group, and 13 mm in the obese group (p = 0.003). There was no significant difference in the postoperative change of cervical lordosis or T1 slope between the groups. Multivariate analysis demonstrated fusions involving the cervicothoracic junction and those involving 5 or more levels significantly affected alignment parameters. There were 27 complications requiring reoperation (14%) with no significant differences among the groups stratified by BMI (p = 0.386).

CONCLUSIONS

Overweight patients (BMI>25) with CSM undergoing PCF had a greater increase in SVA than normal weight patients while reoperation rates were similar. In addition, preoperative CL increased with increasing BMI, although this trend was not Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation significant and there was not found to be a significant difference between the change in CL from baseline to post-fusion between BMI cohorts. This study further highlights the importance of considering BMI when attempting to optimize sagittal alignment in patients undergoing PCF.

Surgical Impact on Global Sagittal Alignment and Health-Related Quality of Life Following Cervical Kyphosis Correction Surgery: Systematic Review

When spinal imbalance occurs, the human body reacts through various compensatory mechanisms to maintain the head over the pelvis and to retain a horizontal gaze. These compensations occur through mobile spine segments as well as pelvic tilt and lower extremities. The purpose of this review was to understand the surgical impact on global sagittal alignment and health-related quality of life (HRQoL) following cervical kyphosis correction surgery. The cervical kyphosis correction surgery induces reciprocal changes in craniocervical and thoracolumbar alignment. Successful cervical deformity correction needs to focus not only on restoring proper cervical lordosis, but also on achieving global balance of the cervical spine with other parts of the spine. The goal of the surgery is to achieve occiputtrunk (OT) concordance (the center of gravity-C7 sagittal vertical axis < 30 mm) and cervical sagittal balance. Once OT-concordance is achieved, subsequent thoracolumbar alignment changes occur as needed to harmonize global spinal alignment. Reciprocal changes after surgery exhibit different patterns depending on whether patients have compensation ability in their thoracolumbar spine or not. C2–7 sagittal vertical axis and sagittal morphotype of the cervical kyphosis are correlated with HRQoL. Changes in cervical lordosis minus T1 slope correlate to HRQoL improvements.

Sagittal alignment of the cervical spine: do we know enough for successful surgery?

Over the past decade, there has been growing interest in the sagittal alignment of the cervical spine and its correlation to clinical outcomes. It is now known that cervical lordosis is not universally physiological and should not be pursued in all patients undergoing surgery. Rather, it is increasingly understood that it is how these angular parameters (lordosis or kyphosis) interact with translational parameters that is reflective of overall cervical spine and whole spine balance, which in turn impacts patient outcomes. This review synthesises currently available evidence relating to the sagittal alignment of the cervical spine. Radiographic assessment of the cervical spine including horizontal gaze is discussed and alignment in physiological and pathological states analysed. The interdependence of spinal segments is reviewed, with cervical alignment correction influencing the adjacent thoracic spine, and similarly lumbar lordosis (LL) and global balance correction changing cervical spine alignment. Cervical kyphosis with associated cervical sagittal imbalance is known to lead to poorer post-operative outcomes, and this dichotomy in outcomes has not been shown to improve even with alignment correction. Further work is required to uncover the extent to which cervical spine alignment correction should be attempted toward improved patient outcomes, in order to plan and deliver patient-specific surgical realignment targets.

Clinical application of large channel endoscopic decompression in posterior cervical spine disorders

Background

We investigated the clinical value of posterior percutaneous endoscopic decompression (PED) for single-segment cervical spondylotic myelopathy (CSM) and cervical spondylotic radiculopathy (CSR). Methods: Clinical data from February 2016 to March 2018 were collected for 32 patients with single-segment CSM or CSR who underwent posterior cervical percutaneous large channel endoscopic decompression and completed a regular follow-up exam at 12 months after surgery. Patient data included: age (range 30–81 years and mean of 49.5 years) and surgical information (operation time, bleeding volume, hospital stay, complications, etc.). The Japan Orthopedic Association (JOA) score and pain visual analog scale (VAS) were used to evaluate the surgical outcome for each patient. Cervical spine radiographs were used to evaluate cervical curvature (Cervical spondylotic angle (CSA), C2–7 Cobb angle) and CT and MRI were used to assess the extent of laminectomy and nerve root decompression. The JOA score, VAS score, cervical curvature were analyzed statistically, and the clinical outcome was evaluated using modified Macnab criteria at the last patient follow-up exam.

Results

The JOA and VAS scores were compared before and after surgery (1 day Pre-op; 3 days, 3 months and 12 months Post-op). The differences were statistically significant (P < 0.05). There were significant differences in cervical curvature (C2–7 Cobb angle) between the time points (1 day Pre-op; 3 days, 3 months and 12 months Post-op), but the differences were no statistically significant in CSA angle (P < 0.05) The operation time range was 45–110 min (mean 68.6 ± 23.8 min); the intraoperative blood loss range was 20–85 ml (mean28 ± 14.8 ml), and the hospital stay was 3–8 days (mean4.5 days). At the last follow-up, the clinical efficacy was evaluated using modified Macnab criteria. The results were excellent in 18 cases, good in 11 cases, and fair in 3 cases. The combined excellent and good rate was 93.75%. Postoperative CT and MRI showed that the compression of the spinal cord or nerve roots was completely relieved.

Conclusion

Endoscopic decompression of posterior cervical vertebral disorders is a safe, effective, and minimally invasive surgical procedure with rapid recovery times. This procedure warrants additional research and clinical application.

Clinical recovery after 5 level of posterior decompression spine surgeries in patients with cervical spondylotic myelopathy: A retrospective cohort study

BACKGROUND/OBJECTIVE

The selection of surgical technique in patients with cervical spondylotic myelopathy relies on the surgeon(s) and patients' conditions. The objectives of the study were to test the hypotheses that French-door laminoplasty recovers faster than laminectomy and has good outcome measures.

METHODS

Data regarding surgical, radiological, and clinical outcome measures of 330 patients with cervical spondylotic myelopathy operated under French-door laminoplasty (fdLP group, n = 110), open-door laminoplasty (odLP group, n = 110), or laminectomy (LC group, n = 110) were collected from the records of institute and analyzed.

RESULTS

Patients of fdLP group (p < 0.0001, q = 11.65) and odLP group (p < 0.0001, q = 11.27) both had significantly improved modified Rankin scale score than those of LC group. In addition, patients of fdLP group had minimum blood loss during operations and that was maximum for patients of the LC group. Unlike patients of fdLP group (p < 0.0001, q = 80) and LC group (p < 0.0001, q =122), those of odLP group had lost more amount of cervical lordotic after surgery. Open-door laminoplasty had significantly reduced cervical range of motion than laminectomy (p < 0.0001, q = 15.45) and French-door laminoplasty (p < 0.0001, q = 13.45). After 12-months, fdLP group had higher bone union rate than odLP group (p = 0.007, q = 3.395) and LC group (p = 0.007, q = 4.243). French door laminoplasty had a better postoperative quality of life.

CONCLUSIONS

Among the posterior decompression spine surgeries, French-door laminoplasty is superior surgical procedure than laminectomy and could be superior surgical technique than open-door laminoplasty.

A Case of Spinal Cord Compression Due to Paraspinal Musculature After Cervical Laminectomy

BACKGROUND

Only a few cases of spinal cord compression after cervical laminectomy have been reported.

CASE DESCRIPTION

We report a case of tetraparesis after executing a C3-C6 anterior and posterior decompression and fusion. Cervical magnetic resonance imaging demonstrated a spinal cord compression due to the impingement of the paraspinal muscles through the laminectomy. The patient experienced a spontaneous neurological recovery and the follow-up cervical magnetic resonance imaging showed resolution of the spinal cord compression.

CONCLUSIONS

This rare complication should be considered among the others after executing a cervical laminectomy.

Anterior and Posterior Approaches for Cervical Myelopathy: Clinical and Radiographic Outcomes

STUDY DESIGN

A retrospective cohort study.

OBJECTIVE

The aim of this study was to identify advantages and disadvantages of the anterior and posterior approaches in the treatment of cervical stenosis and myelopathy.

SUMMARY OF BACKGROUND DATA

Both anterior and posterior surgical approaches for cervical stenosis and myelopathy have been shown to result in improvement in health-related outcomes. Despite the evidence, controversy remains regarding the best approach to achieve decompression and correct deformity.

METHODS

We retrospectively reviewed patients with cervical stenosis and myelopathy who had undergone anterior cervical fusion and instrumentation (n = 38) or posterior cervical laminectomy and instrumentation (n = 51) with at least 6 months of follow-up. Plain radiographs, magnetic resonance imaging, and computed tomography scans, as well as health-related outcomes, including Visual Analog Scale for neck pain, Japanese Orthopedic Association score for myelopathy, Neck Disability Index, and Short Form-36 Health Survey, were collated before surgery and at follow-up (median 12.0 and 12.1 months for anterior and posterior group, respectively).

RESULTS

Both anterior and posterior approaches were associated with significant improvements in all studied quality of life parameters with the exception of general health in the anterior group and energy and fatigue in the posterior group. In the anterior group, follow-up assessment revealed a significant increase in C2-7 lordosis. Both approaches were accompanied by significant increases in C2-7 sagittal balance [sagittal vertical axis (SVA)]. There were two complications in the anterior group and nine complications in the posterior group; the incidence of complications between the two groups was not significantly different.

CONCLUSION

When the benefits of one approach over the other are not self-evident, the anterior approach is recommended, as it was associated with a shorter hospital stay and more successful restoration of cervical lordosis than posterior surgery.

LEVEL OF EVIDENCE

3.

Limited laminectomy and foraminal decompression combined with internal fixation for treating multi-segment cervical spondylotic myelopathy: Does it effectively improve neurological function and prevent C5 palsy?

Laminectomy is an effective surgical treatment for multi-segment cervical spondylotic myelopathy (M-CSM) but usually results in C5 palsy. Some surgical techniques to restore the spinal sequence, increase the intervertebral foramen diameter, and limit the spinal cord drift distance have been proposed; however, it is unclear whether these procedures can avoid this complication.To investigate the clinical efficacy of limited laminectomy and foraminal decompression with fixation (LLFDF) for improving neurological recovery and preventing C5 palsy.A total of 71 patients with M-CSM were retrospectively analyzed. Thirty-nine of them were treated with LLFDF (group A) and 32 with normal laminectomy with fixation (NLF; group B) after 3 months of formal conservative treatment. Pre- and postoperative neurological function, spinal cord drift distance, cervical curvature index (CCI), and number of C5 palsy cases were recorded and analyzed.There was no significant intergroup difference in the surgical time or intraoperative blood loss (P >.05). The laminectomy widths in groups A and B were 16.7 ± 2.6 mm and 21.8 ± 2.9 mm, respectively (P <.01), while the spinal cord drift distances were 2.3 ± 0.4 mm and 3.6 ± 0.7 mm, respectively (P <.01). The mean Japanese Orthopedic Association score of both groups increased significantly after surgery (P <.01), and no significant difference was noted at any observation time points (P >.05). Both groups demonstrated significant CCI improvements after surgery compared with those before surgery (P <.01). There were 2 cases of C5 palsy in group A (5.1%) and 8 cases in group B (25.0%), and the difference was significant (P <.05).LLFDF can relieve spinal compression and considerably promote neurological recovery. Moreover, it restricts excessive spinal cord back drifting and decreases the incidence of C5 palsy.

Anterior cervical discectomy and fusion versus hybrid surgery in multilevel cervical spondylotic myelopathy: A meta-analysis

OBJECTIVE

A meta-analysis was performed to compare the radiographic and surgical outcomes between anterior cervical discectomy and fusion (ACDF) and hybrid surgery (HS, corpectomy combined with discectomy) in the treatment for multilevel cervical spondylotic myelopathy (mCSM).

SUMMARY OF BACKGROUND DATA

Both ACDF and HS are used to treat mCSM, however, which one is better treatment for mCSM remains considerable controversy.

METHODS

An extensive search of literature was searched in PubMed/Medline, Embase, the Cochrane library, CNKI, and WANFANG databases on ACDF versus HS treating mCSM from January 2011 to December 2017. The following variables were extracted: blood loss, operation time, fusion rate, Cobb angles of C2-C7, total complications, dysphagia, hoarseness, C5 palsy, infection, cerebral fluid leakage, epidural hematoma, and graft subsidence. Data analysis was conducted with RevMan 5.3 and STATA 12.0.

RESULTS

A total of 4 studies including 669 patients were included in our study. The pooled analysis showed that there were no significant difference in the operation time, fusion rate, Cobb angles of C2-C7, dysphagia, hoarseness, C5 palsy, infection, cerebral fluid leakage, epidural hematoma, and graft subsidence. However, there were significant difference between 2 groups in blood loss [P < .00001, SMD = -30.29 (-45.06, -15.52); heterogeneity: P = .38, I = 0%= and total complications [P = .04, OR = 0.66 95%CI (0.44, 0.98); heterogeneity: P = .37, I = 4%].

CONCLUSIONS

Based on our meta-analysis, except for blood loss and total complications, both ACDF and hybrid surgery are effective options for the treatment of multilevel cervical spondylotic myelopathy.

Symptomatic cord compression by paraspinal musculature following cervical laminectomy: rare complication

PURPOSE

Cervical laminectomy is an effective treatment for multilevel cervical compressive myelopathy. Symptomatic spinal cord compression (SSCC) by paraspinal musculature (PSM) following cervical laminectomy is rarely reported. The aim of this study was to evaluate the frequency and pathogenesis of this complication after cervical laminectomy.

METHODS

Between 2007 and 2016, the medical records of 1309 cervical laminectomy patients were reviewed. From these 1309 records, seven patients (five men and two women; average age, 64.12 years; range 48-78 years) with SSCC by PSM following cervical laminectomy were identified. The incidence and possible risk factors of this rare condition were evaluated.

RESULTS

The frequency of SSCC by PSM following cervical laminectomy was 0.53%. Presenting symptoms included paralyses and paresthesias, depending on the level and severity of cervical spinal cord compression. The initial onset of neurologic deterioration varied from 12 h to 21 days after operation. Most patients recovered well after surgical management with an average Barthel index of 74.3 at 6 months after surgery. In comparison with 63 controls, this rare complication was associated with preoperative cervical kyphosis, prior antiplatelet therapy, and posterior decompression with prone position.

CONCLUSIONS

SSCC by PSM is a rare but devastating complication following cervical laminectomy, especially in those patients with preoperative kyphosis, prior antiplatelet treatment, and decompression with prone position. MRI is an ideal tool to identify this complication. Rapid cervical cord decompression and avoidance of recurrent compressive events can achieve a good clinical outcome. These slides can be retrieved under Electronic Supplementary Material.

An algorithmic strategy of surgical intervention for cervical degenerative kyphosis

PURPOSE

Correction surgery for cervical degenerative kyphosis (CDK) may carry a greater risk of causing neural complications such as spinal cord injury and C5 nerve palsy because spinal canal stenosis, osteoarthritis of the facet, and consequent foraminal stenosis may coexist with CDK. We have produced an algorithmic strategy of surgical intervention for CDK, and report the outcome.

METHODS

Thirty-one patients who underwent correction surgery for CDK, with a kyphotic angle of 20° or more (from 20 to 74) were involved. An algorithmic surgical strategy is shown. Clinical and radiological outcomes were examined amongst the groups.

RESULTS

Recovery rate of the JOA score was a mean of 44%. Preoperative kyphotic angle and correction angle were; 24.4°and 26.5°in P, 38.4°and 41.1°in AP, and 42.0°and 46.9°in PAP respectively. No spinal cord injury was found. Five cases of C5 nerve palsy occurred in P, and one in AP. Four cases of C5 palsy occurred in seven patients in PAP, although prophylactic foraminotomy was performed. All C5 palsy patients recovered fully at follow-up.

CONCLUSIONS

This study showed that our algorithmic surgical strategy for CDK is acceptable because we obtained good outcomes, and no catastrophic complications occurred. Although we did not intend to obtain excessive postoperative lordosis, we still had several incidence of C5 nerve palsy. We have to be aware of this incidence in PAP, which required a massive range of realignment. The incidence occurred even after we performed prophylactic foraminotomy, however, this procedure may lessen the severity of C5 palsy because those were all transient.

Combined Laminoplasty and Posterior Fusion for Cervical Spondylotic Myelopathy Treatment: A Literature Review

Study Design

A literature review.

Purpose

To explore the utility of laminoplasty in combination with instrumented fusion, with a focus on neurological outcomes and changes in kyphotic deformity.

Overview of Literature

Management of cervical spondylotic myelopathy (CSM) to reduce morbidity within the neurosurgical population.

Methods

A US National Library of Medicine PubMed search was conducted for manuscripts pertaining to cervical laminoplasty and fusion for the management of CSM. Several relevant studies were shortlisted for review, and the bibliographies of the articles were searched for additional references. The search was limited to human studies, English-language literature, and reports on more than one patient.

Results

Combined laminoplasty and fusion was found to provide at least comparable, if not superior, neurological outcomes in specific patient populations with CSM. The Japanese Orthopedic Association scores, local kyphosis, and C2–C7 angle have been reviewed in several manuscripts, and improvement in each of these categories was found with laminoplasty and fusion.

Conclusions

The treatment of CSM necessitates an individualized approach based on the pathoanatomical variation. Laminoplasty and fusion can be appropriately used for patients with CSM in a setting of local kyphotic deformity, ossification of the posterior longitudinal ligament, associated segmental instability, and the need for strong stabilization.

Differences in Cervical Sagittal Alignment Changes in Patients Undergoing Laminoplasty and Anterior Cervical Discectomy and Fusion

OBJECTIVE

Anterior cervical discectomy and fusion (ACDF) and laminoplasty (LP) are the most commonly performed procedures for degenerative cervical spondylosis. Cervical sagittal alignment (CSA) has recently been studied as an important predictor of clinical and radiological outcomes. The data from previous studies are insufficient for analysis using the recently designed CSA parameters, T1 slope (T1s), and T1s minus cervical angle (T1sCA).

METHODS

We retrospectively collected data from patients who underwent ACDF and LP from January 2013 to May 2016. The CSA parameters included CA, sagittal vertical axis, T1s, and T1sCA. T1sCA values were used to evaluate the preoperative cervical balance (T1sCA>20°: imbalance). Clinical results were evaluated using the neck disability index (NDI) and recovery rate (RR) according to the Japanese Orthopedic Association scoring system.

RESULTS

We analyzed the data of 72 patients (ACDF, n=39; LP, n=33). Imbalance on ACDF was associated with an increase in CA (balance: preoperative [PRE], 15.64° → follow-up [F/U], 15.74°, p=0.953; imbalance: PRE, -1.14° → F/U, 8.045°, p=0.008), whereas balance on LP was associated with a significant decrease in CA (balance: PRE, 16.26°→ F/U, 11.59°, p=0.009; imbalance: PRE, 5.36°→ F/U, 2.38°, p=0.249). No significant difference was found in the RR and NDI changes in the ACDF group based on balance, but a significant difference was found in RR in the LP group (balance: 61.65%±19.88%, imbalance: 46.90%±15.71%, p=0.046).

CONCLUSION

We found a significant difference in postoperative alignment in cases of ACDF and LP according to preoperative cervical sagittal balance. The postoperative clinical results of the LP group were more affected by F/U alignment than by the degree of alignment change.

Efficacy of Laminoplasty in Patients with Cervical Kyphosis

Background

The efficacy of laminoplasty in patients with cervical kyphosis is controversial. The purpose of this study was to investigate the impact of the initial pathogenesis on the clinical outcomes of laminoplasty in patients with cervical kyphosis.

Material/Methods

A total of 137 patients with cervical spondylotic myelopathy (CSM) or ossification of the posterior longitudinal ligament (OPLL) underwent laminoplasty from April 2013 to May 2015. The patients were divided into the following 4 groups: lordosis with CSM (LC), kyphosis with CSM (KC), lordosis with OPLL (LO), and kyphosis with OPLL (KO). The clinical outcome measures included the visual analogue scale (VAS) and modified Japanese Orthopedic Association (mJOA) scores, the range of motion (ROM), and the cervical global angle (CGA).

Results

The mean VAS and mJOA scores improved significantly in all groups after surgery. The changes in VAS and mJOA scores were significantly smaller, and the JOA recovery rate was significantly lower, in the KC group than in the LC and KO groups. The mean change in the CGA was greatest in the KC group (>8° towards kyphosis). The preoperative ROM was negatively correlated with the change in CGA and the JOA recovery rate in the KO and KC groups.

Conclusions

We found that laminoplasty is suitable for patients with cervical lordosis and those with mild cervical kyphosis and OPLL, but is not recommended for patients with kyphosis and CSM, particularly those with a large ROM preoperatively.

Surgical and general complications in 2,961 Japanese patients with cervical spondylotic myelopathy: Comparison of different age groups

Introduction: Details of surgical and general complications for patients with cervical spondylotic myelopathy (CSM) are still uncertain. The purpose of this study was to describe surgeries and their complications among Japanese patients with CSM. Methods: The Japanese Society for Spine Surgery and Related Research performed a nationwide survey on spine surgery and complications in 2011. Data of patients with 2,961 CSM >40 years old were included. The clinicopathological variables were basic demographic and clinical information, surgical information, and surgical and general complications. To examine the influence of age, variables were compared among three age groups: patients 40-64 (n=1,123), 65-74 (n=966), and ≥75 (n=872) years of age. Results: The study included 1,970 males and 991 females and the mean age was 64.3 years old. There were 168 anterior (5.7%) and 2,770 posterior (94.2%) approach surgeries. The vast majority of patients with CSM were treated using the posterior approach, 89.4% of whom had decompression surgery only. Anterior surgeries were more common in the younger age group, but posterior surgeries were equally distributed. The incidence of total complications including surgical/general complications was similar for the anterior (16/168; 9.5%) and posterior (295/2,770; 10.6%) approaches. No patient died on the operating table, but four patients (0.1%) died within one month after surgery. No association was detected between complications and age, comorbidity, and other surgical factors. The incidence of complications was similar for the different age groups. However general complications were predominantly observed in the older group and those who had instrumented surgery. Conclusions: The results indicate that the indication and surgical performance for patients with CSM is favorable in Japan, despite the super-aging population. Few serious complications were reported in this study. However, more detailed informed consent about surgical and, in particular, general complications is necessary for the older patients with CSM.

Clinical outcome of laminoplasty for cervical ossification of the posterior longitudinal ligament with K-line (-) in the neck neutral position but K-line (+) in the neck extension position: A retrospective observational study

Patients with cervical ossification of the posterior longitudinal ligament (OPLL) who are K-line (-) are thought to have poor clinical outcomes after laminoplasty. The aim of this study is to compare the clinical results of patients with OPLL who were K-line (-) in the neck neutral position but K-line (+) in the neck extension position (NEP group) with patients with OPLL who were K-line (+) in the neck neutral position (NNP group).Retrospectively, 42 patients who underwent cervical laminoplasty for OPLL by our surgical group during 2012 and 2013 were reviewed and were followed for at least 2 years. The patients were divided into 2 groups according to K-line status. Standing plain radiographs of the cervical spine were obtained pre- and postoperatively. Cervical spine alignment parameters included the C2-7 Cobb angle and range of motion (ROM) measured on lateral radiographs. Clinical evaluation included pre- and postoperative JOA, NDI, and VAS scores.Ten patients were classified in the NEP group, and 32 patients were classified in the NNP group. Preoperatively, the OPLL involved segments were 4.10 ± 1.66 in the NEP group and 2.53 ± 1.16 in the NNP group (P = .005). The canal-occupying ratios were 58.40 ± 11.11% in the NEP group and 29.08 ± 11.38% in the NNP group (P < .001). The mean Cobb angle of both the groups had not changed significantly at the last follow-up. The mean cervical ROM of both the groups had decreased at the last follow-up. The mean JOA score of the NEP group improved significantly from 9.70 ± 2.16 to 12.50 ± 2.27 (P = .014). The mean JOA score of the NNP group improved significantly from 11.91 ± 1.69 to 14.93 ± 1.58 (P < .001). The mean JOA recovery rate was 32.71 ± 40.45% in the NEP group and 59.00 ± 33.80% in the NNP group (P = .036). The NDI scores of both groups were significantly decreased, and the VAS scores of both groups had not changed significantly at the last follow-up.Laminoplasty is a relatively effective and safe procedure for patients with K-line (-) in the neck neutral position but K-line (+) in the neck extension position. Instead of anterior surgery, we recommend laminoplasty for those patients with OPLL extending to 3 or more segments.

Effect of correction surgery for cervical kyphosis on compensatory mechanisms in overall spinopelvic sagittal alignment

PURPOSE

Progression of kyphotic deformity at the middle/lower cervical spine can cause difficulty with horizontal gaze, so compensation at other spinopelvic parts may occur. However, the precise mechanism remains unclear. The present study investigated the effect of correction surgery for cervical kyphosis on the compensatory mechanisms in overall spinopelvic sagittal alignment.

METHODS

Forty-one patients, comprising 23 males and 18 females (mean age 67 years), underwent correction surgery for cervical kyphosis using the posterior screw-rod system. Spinopelvic lateral radiographs in the standing position were taken before and after surgery. C0-1 angle, C1-2 angle, clivo-axial angle (CAA), C2-7 angle, thoracic kyphosis, lumbar lordosis, pelvic incidence, pelvic tilt, and sacral slope were measured. Correlations between C2-7 angle and these parameters before surgery, and correlations between the correction angle of cervical kyphosis and postoperative changes of these parameters were evaluated.

RESULTS

Negative correlations were found between the C2-7 angle and CAA (R = -0.640, p < 0.01), and C2-7 angle and C0-1 angle (R = -0.762, p < 0.001) before surgery. Negative correlations were found between the correction angle of C2-7 and change of CAA (R = -0.718, p < 0.001), and between the correction angle of C2-7 and change of C0-1 angle (R = -0.672, p < 0.01) after surgery.

CONCLUSIONS

The present study demonstrated that C0-1 angle and CAA are more important in the compensatory mechanism for kyphotic deformity at the middle/lower cervical spine compared to downward parameters. That is, to maintain horizontal gaze, lordosis increases at the cranio-cervical junction with greater kyphosis at the middle/lower cervical spine. Correction of cervical kyphosis in the middle/lower cervical spine resulted in normalization of the C0-1 angle and CAA because the compensatory mechanism at the cranio-cervical junction for obtaining horizontal gaze was no longer necessary after surgical intervention.

Effect of Cervical Sagittal Balance on Laminoplasty in Patients With Cervical Myelopathy

STUDY DESIGN

Retrospective clinical study.

OBJECTIVE

We evaluated the relationship between cervical sagittal alignment parameters and clinical status in patients with cervical myelopathy and analyzed the effect of cervical sagittal balance on cervical laminoplasty.

METHODS

Patients with cervical myelopathy (n = 110) who underwent laminoplasty were included in this study. The relationship between cervical sagittal alignment parameters and clinical status was evaluated. The changes in radiographic cervical sagittal parameters and clinical status 2 years after surgery were compared between patients with preoperative C2-7 SVA ≥35 mm (group A) and those with preoperative C2-7 SVA <35 mm (group B).

RESULTS

Preoperatively, C2-7 SVA had no correlation with defined health-related quality of life evaluation scores. At 2-year follow-up, the improvement in SF-36 physical component summary was significantly lower in group A than in group B. The postoperative change of C2-7 SVA did not significantly differ in 2 groups. Patients in group A maintained cervical regional balance after laminoplasty but experienced extensive postoperative neck pain.

CONCLUSIONS

Our patients with a C2-7 SVA of ≥35 mm maintained cervical regional balance after laminoplasty and their improvement in myelopathy was equivalent to that in patients with a C2-7 SVA of <35 mm. However, the patents with a C2-7 SVA of ≥35 mm experienced severe postoperative neck pain. C2-7 SVA is a parameter worth considering because it can lead to poor QOL and axial neck pain after laminoplasty.

Anterior cervical discectomy and fusion versus anterior cervical corpectomy and fusion in multilevel cervical spondylotic myelopathy: A meta-analysis

BACKGROUND

Both anterior cervical discectomy and fusion (ACDF) and anterior cervical corpectomy and fusion (ACCF) are used to treat multilevel cervical spondylotic myelopathy (mCSM); however, which one is better treatment for mCSM remains considerable controversy. A meta-analysis was performed to compare clinical outcomes, radiographic outcomes, and surgical outcomes between ACDF and ACCF in treatment for mCSM.

METHODS

An extensive search of literature was performed in Pubmed/MEDLINE, Embase, the Cochrane library, CNKI, and WANFANG databases on ACDF versus ACCF treatment for mCSM from January 2011 to August 2016. The following variables were extracted: length of hospital stay, blood loss, operation time, Japanese Orthopedic Association (JOA) scores, Neck Disability Index (NDI) score, fusion rate, Cobb angles of C2 to C7, dysphagia, hoarseness, C5 palsy, infection, cerebral fluid leakage, donor site pain, epidural hematoma, graft subsidence, graft dislodgment, pseudoarthrosis, and total complications. Data analysis was conducted with RevMan 5.3 and STATA 12.0.

RESULTS

A total of 8 studies containing 878 patients were included in our study. The results showed that ACDF is better than ACCF in the angle of C2 to C7 at the final follow-up (P < 0.00001, standardized mean difference = 4.76 [3.48, 6.03]; heterogeneity: P = 0.17, I = 43%), C5 plasy (P = 0.02, odds ratio [OR] 0.42, 95% confidence interval [CI] 0.21, 0.86; heterogeneity: P = 0.52, I = 0%), blood loss (P < 0.00001, standardized mean difference = -53.12, 95% CI -64.61, -41.64; heterogeneity: P = 0.29, I = 20%), fusion rate (P = 0.04, OR 2.54, 95% CI 1.05, 6.11; heterogeneity: P = 0.29, I = 20%), graft subsidence (P = 0.004, OR 0.11, 95% CI 0.02, 0.48; heterogeneity: P = 0.94, I = 0%), and total complications (P = 0.0009, OR 0.56, 95% CI 0.40, 0.79; heterogeneity: P = 0.29, I = 18%).However, there are no significant differences in length of hospital stay, operation time, JOA scores, NDI scores, preoperative angle of C2 to C7, dysphagia, hoarseness, infection, cerebral fluid leakage, donor site pain, epidural hematoma, graft dislodgment, and pseudoarthrosis (all P > 0.05).

CONCLUSIONS

Based on our meta-analysis, our results suggest that both ACDF and ACCF are good plans in clinical outcomes; however, ACDF is a better choice in radiographic outcomes and total complications for the treatment of multilevel CSM.

Degenerative cervical myelopathy

Cervical myelopathy is the most common cause of acquired spinal cord compromise. The concept of degenerative cervical myelopathy (DCM), defined as symptomatic myelopathy associated with degenerative arthropathic changes in the spine axis, is being introduced. Given its progressive nature, treatment options have to be chosen in a timely manner. Surgical options include anterior discectomy and fusion (ACDF), anterior corpectomy and fusion (ACCF), arthroplasty (in highly select cases), posterior laminectomy with/without fusion, and laminoplasty. Indications for each should be carefully considered in individual patients. Riluzole, a sodium-glutamate antagonist, is a promising option to optimize neurologic outcomes post-surgery and is being examined in the CSM-Protect Randomized Controlled Trial. Preoperative risk assessment is mandatory for prognostication. Sagittal alignment is known to play an important role to optimize surgical outcome. Guidelines for optimal management of DCM are in process. In principle, all but the mildest cases of DCM should be offered surgery for optimal outcome.

Long-term outcomes and prognostic analysis of modified open-door laminoplasty with lateral mass screw fusion in treatment of cervical spondylotic myelopathy

OBJECTIVES

The purpose of the present study was to explore and analyze the long-term outcomes and factors that affect the prognosis of expansive open-door laminoplasty with lateral mass screw fusion in treatment of cervical spondylotic myelopathy (CSM).

METHODS

We retrospectively reviewed 49 patients with multilevel CSM who had undergone expansive open-door laminoplasty with lateral mass screws fixation and fusion in our hospital between February 2008 and February 2012. The average follow-up period was 4.6 years. The clinical data of patients, including age, sex, operation records, pre- and postoperation Japanese Orthopedic Association (JOA) scores, cervical spine canal stenosis, and cervical curvature, were collected. Increased signal intensity (ISI) on T2-weighted magnetic resonance imaging and ossification of the posterior longitudinal ligament were also observed. Paired t-test was used to analyze the treatment effectiveness and recovery of neuronal function. The prognostic factors were analyzed with multivariable linear regression model.

RESULTS

Forty-nine patients with CSM with a mean age of 59.44 years were enrolled in this study. The average of preoperative JOA score was 9.14±2.25, and postoperative JOA score was 15.31±1.73. There was significant difference between the pre- and postoperative JOA scores. The clinical improvement rate was 80.27%. On follow-up, five patients had complaints of neck and shoulder pain, but no evidence of C5 nerve palsy was found. Developmental cervical spine canal stenosis was present in all patients before surgery. Before surgery, ISI was observed in eight patients, while ossification of the posterior longitudinal ligament was found in 12 patients. The average of preoperative cervical curvature was 21.27°±8.37° and postoperative cervical curvature was 20.09°±1.29°, and there was no significant difference between the pre- and postoperative cervical curvatures. Multivariable linear regression analysis results showed that the postoperation JOA scores were significantly affected by age, preoperative JOA scores, and preoperative ISI. Except one case of epidural hematoma, there were no complications associated with the surgery.

CONCLUSION

Treatment of CSM with posterior open-door laminoplasty with lateral mass screw fusion is effective with few complications. In addition, the normal cervical lordosis was well maintained. Age, preoperative JOA scores, and preoperative ISI were the independent factors that significantly affect disease prognosis and surgical outcomes.

Laminoplasty instead of laminectomy as a decompression method in posterior instrumented fusion for degenerative cervical kyphosis with stenosis

Background

Posterior laminectomy with instrumented fusion is a standard procedure for treating degenerative cervical kyphosis with stenosis (DCKS). Two major disadvantages of the surgery are adhesion of the dural membrane with significant disfiguring of cervical spine and a small fusion bed around the lateral mass. One of the advantages of laminoplasty over laminectomy is the protection of the dural membrane from adhesion through preservation of posterior bony elements. This study presents the surgical outcomes of laminoplasty, instead of laminectomy, as a decompression method applied in posterior instrumented fusion for DCKS.

Methods

A consecutive single center series of twenty cases between 2008 and 2011 were retrospectively reviewed. They were diagnosed as DCKS and received anterior cervical fusion followed by expansive open door laminoplasty and lateral mass or pedicle screw instrumented fusion. We collected the functional scores and changes of cervical curvature on the basis of dynamic lateral films preoperatively and postoperatively. We used computed tomography scans and magnetic resonance imaging (MRI) to evaluate the status of fusion and decompression.

Results

The mean age at the time of surgery was 67.6 ± 15.2 years. Half of the patients were older than 75 years. All functional scores and cervical lordotic curvatures markedly improved. No recurrence of spinal cord compression was caused by closure of opened laminae, according to MRI study that was conducted 12 months postoperatively. No pseudarthrosis or hardware loosening was observed 24 months postoperatively.

Conclusion

The surgical aims for DCKS are adequate decompression, correction of kyphosis, and solid instrumented fusion. Laminoplasty applied in cervical fusion as a decompression method seems to lead to a favorable functional recovery and reduces the complications of perineural adhesion that typically occur after laminectomy. In addition, laminoplasty affords an additional fusion bed at the hinge side and this advantage benefits solid fusion mass formation for the patients who suffered from DCKS.

Single-door cervical laminoplasty using titanium miniplates alone

PURPOSE

To review outcome of 29 patients who underwent single-door cervical laminoplasty for myelopathy using titanium miniplates alone.

METHODS

Records of 20 men and 9 women aged 35 to 79 (mean, 64.3) years who underwent single-door cervical laminoplasty for myelopathy using titanium miniplates alone were reviewed. A total of 125 laminae were opened; 97 of them were fixed with a titanium miniplate. In 19 patients, a 20-hole titanium miniplate bent to the contour of a lamina was used and fixed into 3 laminae at alternate levels. In the remaining 10 patients, the pre-contoured ARCH Laminoplasty System was used and fixed into all laminae. In most patients, screw fixation was unicortical, and no spacer or bone graft was used.

RESULTS

The mean follow-up duration was 4 (range, 2-9) years. At one-year follow-up, the mean Japanese Orthopaedic Association (JOA) score improved from 9.2 to 13.2 (p<0.001). The mean JOA recovery rate was 64%. No patient had neurological deterioration. The mean anteroposterior diameter increased from 14.3 mm to 19.7 mm; the mean increase was 6.1 mm in the plated laminae and 5.3 mm in the unplated laminae (p=0.11). Out of the 125 laminae, there were 2 hinge non-unions in the unplated laminae, and 2 screw pullouts (not associated with plate loosening). No patient had penetration into the vertebral foramen or neuroforamen. Spring-back closure occurred in 5 (18%) of the 28 unplated laminae, with a mean of <3 mm loss of the initial expansion. Two patients developed transient C5 palsy presenting as shoulder abduction weakness. One patient had a delayed dural tear due to a sharp spike at the edge of the opened C6 lamina.

CONCLUSION

Single-door cervical laminoplasty using miniplates alone is a safe technique and achieves a high hinge union rate, good canal expansion, and neurological recovery.

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.