Comparison of laminoplasty versus laminectomy and fusion in the treatment of multilevel cervical ossification of the posterior longitudinal ligament: A systematic review and meta-analysis

Radiographic characterization of OPLL progression in patients receiving laminoplasty with a minimum of two-years follow-up

Ossification of the posterior longitudinal ligament (OPLL) is a common cause of degenerative cervical myelopathy (DCM) in Asian populations. Characterization of OPLL progression following laminoplasty remains limited in the literature. 29 patients with OPLL received cervical laminoplasty and a minimum of 2-years follow-up. Clinical and radiological surveillance occurred at 3-months, 6-months, 12-months post-op and then at yearly intervals. Transverse (anteroposterior) diameter and sagittal length of OPLL in relation to their cervical vertebral level of localisation was assessed upon immediate post-op radiographs compared to those obtained at subsequent follow-up. OPLL progression was defined as an increase in transverse dimensions and/or length by ≥ 2 mm. The average period of clinical follow-up was 6.7 ± 3.3 years. Upon latest follow-up, 79% of patients demonstrated at least 2 mm of transverse or longitudinal progression of OPLL. This corresponded to 2-years and 5-year progression rates of 54% and 71% respectively. OPLL located over C5 demonstrated the greatest transverse progression rate at (0.24 ± 0.34 mm / year). The mean overall longitudinal progression rate was 1.61 ± 2.06 mm / year. No patients experienced neurological decline resulting from OPLL progression requiring revision decompression during the period of post-operative observation. Characterizing transverse and longitudinal progression by cervical level via radiographs has implications in surgical planning for OPLL and should be consolidated upon post-operative CT/MRI scans as well as larger sample sizes.

Cervical kyphosis after posterior cervical laminectomy with and without fusion

BACKGROUND

Cervical posterior instrumentation and fusion is often performed to avoid post-laminectomy kyphosis. However, larger comparative analyses of cervical laminectomy with or without fusion are sparse.

METHODS

A retrospective, two-center, comparative cohort study included patients after stand-alone dorsal laminectomy with (n = 91) or without (n = 46) additional fusion for degenerative cervical myelopathy with a median follow-up of 59 (interquartile range (IQR) 52) months. The primary outcome was the C2-7 Cobb angle and secondary outcomes were Neck Disability Index (NDI), modified Japanese Orthopaedic Association (mJOA) scale, revision rates, T1 slope and C2-7 sagittal vertical axis (C2-7 SVA) at final follow-up. Logistic regression analysis adjusted for potential confounders (i.e. age, operated levels, and follow-up).

RESULTS

Preoperative C2-7 Cobb angle and T1 slope were higher in the laminectomy group, while the C2-7 SVA was similar. The decrease in C2-7 Cobb angle from pre- to postoperatively was more pronounced in the laminectomy group (- 6° (IQR 20) versus -1° (IQR 7), p = 0.002). When adjusting for confounders, the decrease in C2-7 Cobb angle remained higher in the laminectomy group (coefficient - 12 (95% confidence interval (CI) -18 to -5), p = 0.001). However, there were no adjusted differences for postoperative NDI (- 11 (- 23 to 2), p = 0.10), mJOA, revision rates, T1 slope and C2-7 SVA.

CONCLUSION

Posterior cervical laminectomy without fusion is associated with mild loss of cervical lordosis of around 6° in the mid-term after approximately five years, however without any clinical relevance regarding NDI or mJOA in well-selected patients (particularly in shorter segment laminectomies of < 3 levels).

Comparative Analysis of Postoperative Sagittal Balance in Expansive Open-Door Laminoplasty versus Laminectomy with Fusion for Multilevel Ossification of Posterior Longitudinal Ligament: A Retrospective Study

BACKGROUND This single-center study included 80 patients with multilevel cervical ossification of the posterior longitudinal ligament (OPLL) and aimed to compare postoperative sagittal balance following treatment with expansive open-door laminoplasty (LP) vs total laminectomy with fusion (LF). MATERIAL AND METHODS Data of 80 patients with multilevel OPLL treated with LP vs LF between January 2017 and January 2022 were retrospectively analyzed. The basic data, cervical sagittal parameters, and clinical outcomes of the patients were counted in the preoperative and postoperative periods, and complications were recorded. Forty patients underwent LP and 40 underwent LF. Cervical sagittal parameters were compared between and within the 2 groups. Clinical outcomes and complications were compared between the 2 groups. RESULTS At last follow-up, the postoperative C2-C7 Cobb angel, T1 slope (T1S), and C7 slope (C7S) were significantly higher in the LF group than in the LP group (P<0.001). C2-C7 SVA (cSVA) was slightly higher in the LF group (P>0.05) and significantly higher in the LP group (P<0.05). The incidence of postoperative complications in the LP group was significantly lower than in the LF group (P=0.02). The postoperative scores on the Visual Analog Scale (VAS), Neck Disability Index (NDI), and Japanese Orthopedic Association (JOA) were significantly improved in both groups (P<0.001). CONCLUSIONS Both procedures had good outcomes in neurological improvement. After posterior surgery, the cervical vertebrae all showed a tilting forward. Compared to LP, LF may change cervical balance in Cobb angel, T1S. LF has better efficacy in improving cervical lordosis compared with LP. Patients with high T1 slope after surgery may has more axial pain.

A Novel Posterior Compression Score System for Outcome Prediction in Laminoplasty Treated OPLL Patients: A Propensity-Matched Analysis

STUDY DESIGN

A retrospective observational study.

OBJECTIVE

To describe a novel outcome indication system, the posterior compression score (PCS), and investigate its clinical value in cervical ossification of the posterior longitudinal ligament (OPLL) patients treated with laminoplasty.

METHODS

A total of 282 OPLL patients who underwent laminoplasty from January 2013 to December 2018 were reviewed. The patients were divided into high-score (HS) or low-score (LS) groups based on whether the PCS was over 8. Propensity score matching analysis with a caliper of .1 was used to attenuate the potential selection bias. Clinical measurements, including the Japanese Orthopedic Association (JOA) score, visual analog scale (VAS), neck disability index (NDI), and radiological measurements, including C2-C7 lordotic angle and range of motion (ROM), were compared between the groups.

RESULTS

The mean follow-up period was 29.87 ± 9.17 months. There were no significant differences between the two groups regarding patients' baseline demographical and clinical characteristics after propensity score matching. No significant differences were found in the operative time, blood loss, postoperative VAS score for neck and arm pain, postoperative C2-C7 lordotic angle, or postoperative ROM (P > .05). However, the postoperative JOA score and recovery rate were significantly higher in the HS group than in the LS group, while the postoperative NDI was significantly lower in the HS group (P < .05).

CONCLUSION

OPLL patients with higher PCS scores displayed better clinical outcomes. The novel PCS system is suggested to be a reliable scoring system for surgical outcome evaluation in patients with cervical OPLL.

Effects of Lifestyle Interventions on Health and Life Quality of Colorectal Cancer Survivors: A Systematic Review and Meta-analysis

BACKGROUND

The results of previous studies on the effects of lifestyle interventions on the quality of life (QoL) in colorectal cancer (CRC) survivors remain controversial, and there have been several new publications in this area in recent years.

OBJECTIVES

To assess whether lifestyle interventions can lead to favorable health outcomes and improved QoL in CRC survivors, we performed a meta-analysis.

METHODS

PubMed, EMBASE, Web of Science, and Cochrane Library were systematically searched to obtain relevant literature published from January 1, 1990, to November 1, 2021. The required data were extracted and summarized to compare the physical activity levels, QoL, mental health assessment, and anthropometric data between lifestyle interventions and routine nursing.

RESULTS

Twelve studies were included. Compared with the control group, lifestyle interventions could significantly increase the physical activity time (weighted mean difference [WMD], 9.84; 95% confidence interval [CI], 1.20-18.48; P = .026), metabolic equivalent task levels (WMD, 10.40; 95% CI, 5.30-15.49; P < .001), and Functional Assessment of Cancer Therapy Scale-Colorectal scores (WMD, 3.12; 95% CI, 0.24-5.99; P = .034). However, lifestyle interventions were not noticeably able to improve the fatigue, depression levels, anxiety levels, waist circumference, or body mass index in CRC survivors.

CONCLUSION

Lifestyle interventions could generate an increase in physical activity time, metabolic equivalent task levels, and QoL in CRC survivors.

IMPLICATIONS FOR PRACTICE

Lifestyle interventions in the future that include physical activity, diet, or comprehensive programs are needed to increase physical activity levels and improve QoL in CRC survivors.

Biomechanical evaluation on a new type of vertebral titanium porous mini-plate and mechanical comparison between cervical open-door laminoplasty and laminectomy: a finite element analysis

Objective: Compare the spine's stability after laminectomy (LN) and laminoplasty (LP) for two posterior surgeries. Simultaneously, design a new vertebral titanium porous mini plate (TPMP) to achieve firm fixation of the open-door vertebral LP fully. The objective is to enhance the fixation stability, effectively prevent the possibility of "re-closure," and may facilitate bone healing. Methods: TPMP was designed by incorporating a fusion body and porous structures, and a three-dimensional finite element cervical model of C2-T1 was constructed and validated. Load LN and LP finite element models, respectively, and analyze and simulate the detailed processes of the two surgeries. It was simultaneously implanting the TPMP into LP to evaluate its biomechanical properties. Results: We find that the range of motion (ROM) of C4-C5 after LN surgery was greater than that of LP implanted with different plates alone. Furthermore, flexion-extension, lateral bending, and axial rotation reflect this change. More noteworthy is that LN has a much larger ROM on C2-C3 in axial rotation. The ROM of LP implanted with two different plates is similar. There is almost no difference in facet joint stress in lateral bending. The facet joint stress of LN is smaller on C2-C3 and C4-C5, and larger more prominent on C5-C6 in the flexion-extension. Regarding intervertebral disc pressure (IDP), there is little difference between different surgeries except for the LN on C2-C3 in axial rotation. The plate displacement specificity does not significantly differ from LP with vertebral titanium mini-plate (TMP) and LP with TPMP after surgery. The stress of LP with TPMP is larger in C4-C5, C5-C6. Moreover, LP with TMP shows greater stress in the C3-C4 during flexion-extension and lateral bending. Conclusion: LP may have better postoperative stability when posterior approach surgery is used to treat CSM; at the same time, the new type of vertebral titanium mini-plate can achieve almost the same effect as the traditional titanium mini-plate after surgery for LP. In addition, it has specific potential due to the porous structure promoting bone fusion.

The clinical efficacy of laminectomy fusion fixation and posterior single open-door laminoplasty in the treatment of multilevel cervical ossification of the posterior longitudinal ligament (OPLL): a retrospective study

BACKGROUND

To compared the clinical efficacy of two surgical methods, posterior laminectomy fusion fixation, and posterior single open-door laminoplasty, in treating multilevel cervical ossification of the posterior longitudinal ligament (OPLL).

METHODS

The study retrospectively included 102 patients treated between December 2016 and December 2020. The patients were included into an observation group (56 cases) treated with total laminectomy and lateral screw fixation, and a control group (46 cases) treated with single open-door laminoplasty.

RESULTS

After 24 months, both groups showed significant improvement in Japanese Orthopaedic Association (JOA) scores and Visual Analogue Scale (VAS) scores, indicating better clinical symptoms and functional recovery. There was no significant difference in preoperative JOA and VAS scores between the two groups (P > 0.05). At 24 months after surgery, there was no significant difference in JOA and VAS scores between the two groups (P > 0.05). However, the observation group had a significantly higher cervical curvature index (CCI) and lower range of motion (ROM) of the cervical spine compared to the control group (P < 0.05). The CCI in control group was lower than before surgery, while the CCI in observation group was higher than before surgery, and CCI in the control group was considerably lower than that in the observation group (P < 0.05). The complication rate was lower in the control group, with fewer cases of axial symptoms, fifth cervical nerve root palsy, and overall complications. The overall complication rate was 25.0% (14/56) in the observation group and 10.8% (5/46) in the control group (P < 0.05).

CONCLUSIONS

Both posterior laminectomy fusion fixation and posterior single open-door laminoplasty yield positive outcomes in improving clinical neurological function, cervical curvature, range of motion of the cervical spine, and cervical sagittal balance. Although open-door laminoplasty is less effective than total laminectomy in maintaining CCI and sagittal balance, it excels in preserving cervical range of motion, less surgical trauma and complications. Thus, open-door laminoplasty may be a suitable first-choice treatment for multi-segmental cervical OPLL, especially for patients with lordotic cervical spine physiological curvature.

Cervical laminoplasty versus laminectomy and fusion: An umbrella review of postoperative outcomes

While multiple studies exist comparing cervical laminoplasty (CLP) and posterior cervical laminectomy with fusion (PCF), no clear consensus exists on which intervention is better. An umbrella review helps provide an overall assessment by analyzing a given condition's multiple interventions and outcomes. It integrates all available information on a topic and allows a consensus to be reached on the intervention of choice. A literature search was conducted using specific search criteria in PubMed, Scopus, and Web of Science databases. Titles and abstracts were screened based on inclusion criteria. A full-text review of articles that passed the initial inclusion criteria was performed. Nine meta-analyses were deemed eligible for the umbrella review. Data was extracted on reported variables from these meta-analyses. Subsequent quality assessment using AMSTAR2 and data analysis using the R package metaumbrella were used to determine the significance of postoperative outcomes. When the meta-analyses were pooled, statistically significant differences between CLP and PCF were found for postoperative overall complications rate and postoperative JOA score. PCF was associated with a lower overall complication rate and a higher postoperative JOA score, both supported by a weak level of evidence (class IV). Data regarding all other outcomes were non-significant. Our umbrella review investigates CLP and PCF by providing a comprehensive overview of existing evidence and evaluating inconsistencies within the literature. This umbrella review revealed that PCF had better outcomes for overall complications rate and postoperative JOA than CLP, but they were classified as being of weak significance.

Comparative study of preoperative sagittal alignment between patients with multisegment cervical ossification of the posterior longitudinal ligament and cervical spondylotic myelopathy

BACKGROUND CONTEXT

Preoperative sagittal alignment is of great significance in the development of spinal deformities, degenerative diseases, preoperative planning, postoperative clinical evaluation, and functional recovery. However, few reports have focused on the difference in preoperative sagittal alignment between patients with ossification of the posterior longitudinal ligament (OPLL) and patients with cervical spondylotic myelopathy (CSM).

PURPOSE

To compare preoperative sagittal alignment between patients with multisegment cervical OPLL and multilevel CSM.

STUDY DESIGN

Retrospective study.

PATIENT SAMPLE

A total of 243 patients were included in this study.

OUTCOME MEASURES

The outcome measures were the Japanese Orthopaedic Association (JOA) score, visual analog scale (VAS) score, number of hand actions in 10 seconds, hand-grip strength, C2 to C7 Cobb angle, C2 to C5 Cobb angle, C5 to C7 Cobb angle, C2 to C7 sagittal vertical axis, C7 slope, T1 slope, K-line, K-line tilt, and range of motion (ROM).

METHODS

The outcome measures were calculated in the OPLL group and CSM group and the data were analyzed using the unpaired t-test, χ² test, and one-way analysis of variance.

RESULTS

A total of 243 patients (136 men, 107 women; mean age, 59.1±10.6 years) underwent surgical treatment from September 2013 to December 2021. In total, 123 patients were diagnosed with multisegment cervical OPLL, including continuous type (n=39), segmental type (n=38), and mixed type (n=46). The remaining 120 patients had multisegment CSM. The disease course in the OPLL group was significantly shorter than that in the CSM group (p<.05). Among the above preoperative measurements, the JOA score, number of hand actions in 10 seconds, hand-grip strength, and VAS score were not significantly different between the two groups (p>.05). The C2 to C7 Cobb angle was significantly larger in the OPLL than CSM group (17.7°±9.2° and 14.9°±9.3°, respectively; p< .05), as was the C5 to C7 Cobb angle (10.0°±6.3° and 7.5°±6.1°, respectively; p<.05). The ROM was significantly smaller in the OPLL than CSM group (33.1°±8.1° and 40.1°±10.9°, respectively; p<.001). Within the OPLL group, the ROM was significantly smaller in the continuous type than in the segmental type (p<.05).

CONCLUSION

Patients with multisegment cervical OPLL have greater lordotic preoperative sagittal alignment and smaller preoperative ROM than patients with CSM.

Laminoplasty versus laminectomy with fusion for treating multilevel degenerative cervical myelopathy

Background

Laminectomy with fusion (LF) and laminoplasty (LP) are common posterior decompression procedures used to treat multilevel degenerative cervical myelopathy (DCM). There is debate on their relative efficacy and safety for treatment of DCM. The goal of this study is to examine outcomes and costs of LF and LP procedures for DCM.

Methods

This is a retrospective review of adult patients (<18) at a single center who underwent elective LP and LF of at least 3 levels from C3-C7. Outcome measures included operative characteristics, inpatient mobility status, length of stay, complications, revision surgery, VAS neck pain scores, and changes in radiographic alignment. Oral opioid analgesic needs and hospital cost comparison were also assessed.

Results

LP cohort (n=76) and LF cohort (n=59) reported no difference in neck pain at baseline, 1, 6, 12, and 24 months postoperatively (p>.05). Patients were successfully weaned off opioids at similar rates (LF: 88%, LP: 86%). Fixed and variable costs respectively with LF cases hospital were higher, 15.7% and 25.7% compared to LP cases (p=.03 and p<.001). LF has a longer length of stay (4.2 vs. 3.1 days, p=.001). Wound-related complications were 5 times more likely after LF (13.6% vs. 5.9%, RR: 5.15) and C5 palsy rates were similar across the groups (LF: 11.9% LP: 5.6% RR: 1.8). Ground-level falls requiring an emergency department visit were more likely after LF (11.9% vs. 2.6%, p=.04).

Conclusions

When treating multilevel DCM, LP has similar rates of new or increasing axial neck pain compared to LF. LF was associated with greater hospital costs, length of stay, and complications compared to LP. LP may in fact be a less morbid and more cost-effective alternative to LF for patients without cervical deformity.

Development of an innovative minimally invasive primate spinal cord injury model: A case report

Spinal cord injury (SCI) animal models have been widely created and utilized for repair therapy research, but more suitable experimental animals and accurate modeling methodologies are required to achieve the desired results. In this experiment, we constructed an innovative dorsal 1/4 spinal cord transection macaque model that had fewer severe problems, facilitating postoperative care and recovery. In essence, given that monkeys and humans share similar genetics and physiology, the efficacy of this strategy in a nonhuman primate SCI model basically serves as a good basis for its prospective therapeutic use in human SCI.

Biomechanical evaluation of reconstruction of the posterior complex in restorative laminoplasty with miniplates

OBJECTIVE

To evaluate the biomechanical effects of different miniplates on restorative laminoplasty.

METHODS

Assembled restorative laminoplasty models were developed based on 3D printed L4 lamina. Based on different internal fixations, the research was divided into H-shaped miniplates (HSMs) group, two-hole miniplates (THMs) group, and L-shaped miniplates (LSMs) group. The static and dynamic compression tests were analyzed to investigate the biomechanical effects of different internal fixations in restorative laminoplasty, until the failure and fracture of miniplates, or the collapse of miniplates. The static compression tests adopted the speed control mode, and the dynamic fatigue compression tests adopted the load control mode.

RESULTS

The "door close" and the collapse of lamina occurred in THMs group and LSMs group, and plate break occurred in LSMs group. However, these phenomenon was absent in HSMs group, and only plate crack around a screw and looseness of a screw tail cap were found in HSMs group. The sustainable yield load of HSMs group was greater than that of THMs group and LSMs group (P < 0.05). No significant difference in yielding-displacement was found between HSMs group and LSMs group (P > 0.05), while both were much less than that of THMs (P < 0.05). Moreover, the compressive stiffness and the axial displacement under the same mechanical load were arranged as follows: HSMs group > LSMs group > THMs group (P < 0.05). The results of dynamic compression test revealed that the peak load of HSMs group could reached 873 N and was 95% of the average yield load of the static compression, and was better than that in THMs group and LSMs group (P < 0.05). Besides, according to the fatigue life-peak load diagram, the ultimate load of HSMs group was more than twice that of THMs group or LSMs group.

CONCLUSIONS

The mechanical strength of H-shaped miniplates was superior to two-hole miniplates and L-shaped miniplates in maintaining spinal canal enlargement and spinal stability, and was more excellent in fatigue stability and ultimate load.

[Biomechanical analysis of miniplate fixation systems in restorative laminoplasty for spinal canal reconstruction]

OBJECTIVE

To investigate the biomechanical properties of H-shaped and L-shaped miniplate fixation systems (H-MFS and L-MFS, respectively) in restorative laminoplasty for spinal canal reconstruction (RL-SCR).

METHODS

Laminectomy was performed in a 3D printed L4 vertebral model followed by RL-SCR using H-MFS or L-MFS, and the biomechanical properties of the reconstructed models were evaluated using static and dynamic compression tests. Biomechanical analyses of RL-SCR were also conducted in finite element models of the L3-L5 vertebrae with normal assignment (NA), laminectomy, or fixation with H-MFS or L-MFS, and the range of motion (ROM) of L3-L4 and L4-L5 was evaluated.

RESULTS

In static compression test, the sustained yield load, compression stiffness, yield displacement and axial displacement- axial load were all significantly greater in H-MFS group (P < 0.05). Door closing, lamina collapse and plate breakage occurred in all the models in L-MFS group, and only some models in H-MFS group showed plate cracks and screw loosening. In dynamic compression tests, the peak load in H-MFS group reached 873 N (which was 95% of the average yield load in static compression), significantly greater than that in L-MFS group (P < 0.05). The ultimate load in L-MFS group was only 46.59% of that in H-MFS group (P>0.05). In finite element analysis, the ROM of the L3-L4 and L4- L5 segments were significantly smaller in NA, H-MFS and L-MFS groups than in laminectomy group. Compared with NA group, H-MFS group showed a greater ROM during extension, and L-MFS group showed greater ROM in flexion, extension, bending, and rotation; The overall ROM of the vertebral segments decreased in the order of laminectomy group, L-MFS group, H-MFS group, and NA group.

CONCLUSION

Laminectomy causes structural destruction of the posterior column of the spine to affect its biomechanical stability. RL-SCR can effectively maintain the biomechanical stability of the spine, and H-MFS is superior to L-MFS in maintaining the integrity and biomechanical properties of the reconstructed spinal canal.

Comparison of the outcome after anterior cervical ossified posterior longitudinal ligament en bloc resection versus posterior total laminectomy and fusion in patients with ossification of the cervical posterior longitudinal ligament: a prospective randomized controlled trial

The optimal procedure for the treatment of ossification of the posterior longitudinal ligament (OPLL) remains controversial. The aim of this study was to compare the outcome of anterior cervical ossified posterior longitudinal ligament en bloc resection (ACOE) with posterior laminectomy and fusion with bone graft and internal fixation (PTLF) for the surgical management of patients with this condition. Between July 2017 and July 2019, 40 patients with cervical OPLL were equally randomized to undergo surgery with an ACOE or a PTLF. The clinical and radiological results were compared between the two groups. The Japanese Orthopaedic Association (JOA) score and recovery rate in the ACOE group were significantly higher than those in the PTLF group during two years postoperatively, provided that the canal occupying ratio (COR) was > 50%, or the K-line was negative. There was no significant difference in JOA scores and rate of recovery between the two groups in those in whom the COR was < 50%, or the K-line was positive. There was no significant difference in the Cobb angle between C2 and C7, sagittal vertical axis, cervical range of motion (ROM), and complications between the two groups. Compared with PTLF, ACOE is a preferred surgical approach for the surgical management of patients with cervical OPLL in that it offers a better therapeutic outcome when the COR is > 50%, or the K-line is negative, and it also preserves better cervical curvature and sagittal balance. The prognosis of ACOE is similar to that of PTLE when the COR is < 50%, or the K-line is positive.

Surgical Management of Cervical Ossification of Posterior Longitudinal Ligament: The Treatment Algorithm and Outcome

Introduction Managing patients who present with symptoms of cervical myelopathy secondary to cervical ossification of the posterior longitudinal ligament (OPLL) is challenging. Various factors such as the number of levels involved with OPLL, types of OPLL, canal occupying ratio, K-line characteristics, and C2-C7 lordosis angle were found to guide decision-making and surgical approaches in managing this condition. However, no clear treatment algorithm has been published. This study aims to investigate the outcome of the management of cervical OPLL using a treatment algorithm used in a tertiary university hospital. Methods This is a retrospective cross-sectional study. Patients with cervical myelopathy secondary to cervical OPLL who were treated surgically in our center from 2014 to 2020 were included in this study. Demographic data and preoperative parameters that determined the treatment given according to our treatment algorithm were analyzed. Result A total of 24 patients fit the inclusion and exclusion criteria of the study. The mean recovery rate for all groups is 61.8[Formula: see text]21.9% and the mean postoperative neck disability index (NDI) is 17.83[Formula: see text]16.67%. There was a statistically significant difference between preoperative and postoperative Japanese Orthopaedic Association (JOA) scores for both anterior and posterior surgery subgroups. Conclusion We believe that the treatment algorithm used in our center could benefit other surgeons as a guide in managing patients who suffer from cervical myelopathy secondary to cervical OPLL. Further study including newer techniques would increase the surgeon's arsenal in providing the best outcome in managing this condition.

REVISION RECONSTRUCTION OF THE CERVICAL SPINE IN A PATIENT WITH EARLY DEEP SSI COMPLICATED BY ANGULAR KYPHOSIS: clinical case and literature review

Background. Deep surgical site infection (DSSI) is one of the most severe complications in spinal surgery. The timing and nature of DSSI are the determining criteria in the choice of treatment tactics. Aim. To present a unique clinical case of early deep SSI after ACDF in a patient with multisegmental degenerative spinal canal stenosis, complicated by epidural abscess and angular kyphotic deformity. Angular kyphosis correction, corpectomy of C4-6 and three-column cervical reconstruction were performed in one surgical session. Case presentation. A 57-year-old patient was admitted to the clinic after staged surgical interventions on the cervical spine for multilevel degenerative stenosis of the spinal canal. The primary surgical interventions were complicated by DSSI in the early period after the second surgery with formation of angular kyphosis of the cervical spine. The patient underwent revision one-stage reconstructive intervention to correct the deformity, decompress the spinal canal, and three-column reconstruction of C3-7 segments. Long-term follow-up showed persistent reduction of pain syndrome, improved quality of life and absence of recurrence of DSSI. Conclusion. The presented case illustrates the possibilities of one-stage revision three-column cervical spine reconstruction for correction of sagittal profile, decompression of intracanal neural structures and ensuring stability of operated segments. Use of DSSI treatment algorithms based on Prinz V. and Vajkoczy P. classification contributes to the selection of the optimal tactics of patient management.

Impact of lamina-open side on unilateral open door laminoplasty in patients with degenerative cervical myelopathy

Surgeons should select one side for cervical unilateral open door laminoplasty (UODL). However, few reports suggest proper guidelines for deciding which side to open. The aim of this study is to evaluate the impact of opening side in UODL on dominant cord compressive or symptomatic side. 193 degenerative cervical myeloradiculopathy patients with followed-up more than 2 years were enrolled. In all cases, UODL was performed uniformly on the right side. Patients were sub-grouped based on preoperative dominant 3 characteristics: cord compression, myelopathy symptom and radiculopathy symptom (right, symmetric, left). Pre- and postoperative radiographic and clinical parameters and incidence of postoperative C5 palsy were analyzed and compared among the groups. According to dominant compressive side, there were no significant differences in postoperative radiographic and clinical parameters among three groups. According to dominant myelopathy or radiculopathy symptom side, there were no significant differences of all radiographic and clinical parameters postoperatively, except slightly lower neck VAS in groups of preoperative right dominant myelopathy or radiculopathy symptom side at postoperative 1 month. C5 palsies occurred in twelve patients (6.2%), but the incidences were not different among the groups. Therefore, when performing UODL, the choice of lamina opening side can be left to surgeon's preference.

Different standing postures are the influencing factors for the efficacy of laminoplasty in the treatment of K-Line (-) patients with ossification of the posterior longitudinal ligament

OBJECTIVE

To investigate the relationship between different standing postures and surgical outcomes of K-Line (-) ossification of the posterior longitudinal ligament (OPLL) patients after laminoplasty with a titanium basket. There is a lack of data evaluating the relationship between the postoperative satisfaction of K-Line (-) patients and their standing postures.

METHODS

OPLL patients enrolled in the study were divided into a K-Line (+) group (Group A) and a K-Line (- group (Group B) in natural and relaxed standing positions. We compared the postoperative outcomes after cervical laminoplasty with titanium basket surgery using the Japanese Orthopaedic Association score (JOA), recovery rate and the degree of improvement in the six JOA score items. The degree of satisfaction with the outcome was assessed at the 1-year follow-up using a 7-point numerical rating scale.

RESULTS

A total of 34 K-Line (+) patients with OPLL (age 61.9 ± 2.9 years) in Group A and 40 K-Line (-)patients with OPLL (age 60.4 ± 3.5 years) in Group B in natural and relaxed standing positions were recruited. In Group A, the mean preoperative and postoperative JOA scores were 10.1 ± 1.4 and 13.1 ± 0.8 points, respectively, and in Group B, the mean preoperative and postoperative JOA scores were 9.7 ± 1.3 and 11.1 ± 0.9 points, respectively. A significant improvement in the JOA score was seen in both groups postoperatively, but the recovery rate of the patients' JOA scores was significantly lower in Group B. In Group A, significant improvements were seen in all JOA score items, but in Group B, improvements were seen only in upper- and lower-extremity sensory functions.

CONCLUSION

Different standing postures are risk factors in the treatment of K-Line (-) patients, and therefore, natural and relaxed standing positions should be given more attention before devising the surgical plan.

Clinical Indicators of Surgical Outcomes After Laminoplasty for Patients With Cervical Ossification of the Posterior Longitudinal Ligament: A Prospective Multicenter Study

STUDY DESIGN

A prospective multicenter study.

OBJECTIVE

This study aims to evaluate patient-reported outcomes using the Japanese Orthopedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ) and clarify clinical factors that affect the therapeutic effects for patients with cervical ossification of the posterior longitudinal ligament (OPLL).

SUMMARY OF BACKGROUND DATA

Although previous studies identified factors that affected the surgical outcomes, their assessment was mainly based on the Japanese Orthopedic Association score, which only includes neurological function. Investigating this pathology through multiple functions and quality of life (QOL) is pivotal to understanding the comprehensive clinical pictures of the cervical OPLL and its therapeutic outcomes.

MATERIALS AND METHODS

This study was performed by the Japanese Multicenter Research Organization for Ossification of the Spinal Ligament. A total of 478 patients with myelopathy caused by cervical OPLL from 28 institutions were prospectively registered from 2014 to 2017 and followed up for 2 years. Of the patients, 168 received laminoplasties and fully completed questionnaires. Demographic information, imaging findings, and clinical outcomes were collected. Patients were grouped according to effective or ineffective surgical outcomes as defined by the JOACMEQ using logistic regression analyses.

RESULTS

Laminoplasty resulted in functional improvement in the cervical spine and upper extremity around 40% of the patients, while QOL showed only 21.4% ( P <0.01). Multivariable analyses revealed that younger age and a postoperative decrease in arm or hand pain were correlated with significantly improved function of the upper extremities. A reduction in lower limb pain favorably affected the postoperative lower extremity function. A postoperative reduction in upper extremity pain enhanced the QOL recovery.

CONCLUSIONS

Surgeons should recognize the diversity of surgical outcomes after laminoplasty and understand the necessity of pain management even after the surgery to enhance bodily functions and QOL in patients with cervical OPLL.

Comparative Effectiveness and Functional Outcome of C2 Dome-like Expansive Versus C2 Expansive Open-door Laminoplasty for Upper Cervical Ossification of the Posterior Longitudinal Ligament: A Retrospective Cohort Study

STUDY DESIGN

Retrospective Cohort Study.

OBJECTIVES

This study compared the function and radiographical outcomes of the patients who underwent C2 dome-like expansive laminoplasty to those C2 expansive open-door laminoplasty for the treatment of OPLL with C2 involved.

SUMMARY OF BACKGROUND DATA

There are few comparative studies of these two surgical methods. C2 dome-like and C2 expansive open-door laminoplasty are posterior approaches for posterior longitudinal ligament ossification with C2 level and above.

METHODS

This study performed a retrospective cohort analysis of 59 patients with OPLL up to C2 which cause compression symptoms. 31 patients underwent C2 dome-like expansive laminoplasty with C3-7 expansive open-door laminoplasty (Group Dom) and 28 underwent C2-7 expansive open-door laminoplasty (Group Exp). The preoperative and postoperative space available for cord (SAC) of C2 segment, cervical curvature index of C2-7, C2-7 range of motion, Japanese orthopedic association (JOA) score, visual analog scale (VAS) score, and neck disability index (NDI) were used to assess clinical out-comes and statistically analyzed.

RESULTS

The cervical curvature index, JOA score, and NDI significantly changed at the final follow-up in two groups with no significant intergroup differences. There were no significant differences in preoperative SAC and VAS between the two groups. At the final follow-up, the SAC of C2/3 in Group Exp was significantly larger than Group Dom, while the VAS and range of motion of Group Dom became significantly better than Group Exp.

CONCLUSION

The C2 dome-like expansive laminoplasty can reduce postoperative neck pain more obviously and achieve better cervical curvature. C2 expansive open-door laminoplasty can get more adequate decompression in the spinal canal, which may be recommend to the patients with OPLL occupying more than 50% of the vertebral canal at C2/3, or with developmental spinal stenosis.

LEVEL OF EVIDENCE

3.

Cervical Myelopathy: An Update on Posterior Decompression

STUDY DESIGN

This was a narrative review.

OBJECTIVE

The aim was to discuss current methods and review updated outcome studies regarding posterior decompression in the management of cervical myelopathy.

SUMMARY OF BACKGROUND DATA

Progressive myelopathy in the cervical segments is an indication for urgent surgical management. Although nonoperative treatment is an option in mild to moderate cases, the majority of patients will experience deterioration in neurological function requiring surgical decompression.

METHODS

A review of the literature was performed using PubMed to provide updated information regarding posterior cervical decompression in the management of myelopathy.

RESULTS

There are numerous studies comparing outcome data between cervical laminectomy and fusion with laminoplasty. While each technique has advantages and disadvantages, both provide adequate decompression and good long-term outcomes in patients meeting appropriate criteria.

CONCLUSIONS

Posterior decompression is an important approach for spine surgeons to have in their toolkits when treating cervical myelopathy.

Comparison of laminoplasty and posterior fusion surgery for cervical ossification of posterior longitudinal ligament

This prospective multicenter study, established by the Japanese Ministry of Health, Labour and Welfare and involving 27 institutions, aimed to compare postoperative outcomes between laminoplasty (LM) and posterior fusion (PF) for cervical ossification of the posterior longitudinal ligament (OPLL), in order to address the controversy surrounding the role of instrumented fusion in cases of posterior surgical decompression for OPLL. 478 patients were considered for participation in the study; from among them, 189 (137 and 52 patients with LM and PF, respectively) were included and evaluated using the Japanese Orthopaedic Association (JOA) scores, the JOA Cervical Myelopathy Evaluation Questionnaire (JOACMEQ), and radiographical measurements. Basic demographic and radiographical data were reviewed, and the propensity to choose a surgical procedure was calculated. Preoperatively, there were no significant differences among the participants in terms of patient backgrounds, radiographical measurements (K-line or cervical alignment on X-ray, OPLL occupation ratio on computed tomography, increased signal intensity change on magnetic resonance imaging), or clinical status (JOA score and JOACMEQ) after adjustments. The overall risk of perioperative complications was found to be lower with LM (odds ratio [OR] 0.40, p = 0.006), and the rate of C5 palsy occurrence was significantly lower with LM (OR 0.11, p = 0.0002) than with PF. The range of motion (20.91° ± 1.05° and 9.38° ± 1.24°, p < 0.0001) in patients who had PF was significantly smaller than in those who had LM. However, multivariable logistic regression analysis showed no significant difference among the participants in JOA score, JOA recovery rate, or JOACMEQ improvement at two years. In contrast, OPLL progression was greater in the LM group than in the PF group (OR 2.73, p = 0.0002). Both LM and PF for cervical myelopathy due to OPLL had resulted in comparable postoperative outcomes at 2 years after surgery.

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.

Laminectomy and fusion in multilevel degenerative cervical myelopathy - Correlation between objective and subjective postoperative restriction of cervical spine mobility

For patients with multilevel degenerative cervical myelopathy (DCM), laminectomy and fusion is an established technique. A concomitant effect of multilevel fusion is a restriction of cervical spine mobility. This retrospective study on DCM-patients with at least 4 laminectomy and fusion levels, compares data between objective and subjective restriction of the postoperative cervical spine mobility. The patient-reported restriction of cervical spine mobility was acquired by a five-step score. Measurements of cervical range of motion were performed using the CROM device and were correlated with the subjective scores. Fusion was performed over 6 levels in most of the 36 patients. For the subjective cervical spine mobility, 52.8% reported none to medium, 38.9% severe and 8.3% complete restriction. Mean objective cervical range of motion was 45.0° for flexion-extension, 26.3° for total lateral flexion and 51.4° for total rotation and therefore evidently reduced compared to non-operated patient cohorts in literature. There was a significant medium, negative correlation between the objective measurements and the patient-reported general restriction of cervical spine mobility, and with the physical component summary of SF-8. The significant objective reduction of cervical range of motion after laminectomy and multilevel fusion correlates with the patient-reported assessment for general restriction.

Perioperative Complications in Posterior Surgeries for Cervical Ossification of the Posterior Longitudinal Ligament: A Prospective Nationwide Investigation

STUDY DESIGN

This was a prospective multicenter study.

OBJECTIVE

The aim of this study was to investigate the perioperative complications of posterior surgeries for the treatment of cervical ossification of the posterior longitudinal ligament (OPLL).

SUMMARY OF BACKGROUND DATA

Surgical treatment for cervical OPLL has a high risk of various complications. Laminoplasty (LAMP) and posterior decompression and instrumented fusion (PDF) are effective for multilevel cervical OPLL; however, few studies have focused on the surgical complications of these 2 procedures.

MATERIALS AND METHODS

We prospectively included 380 patients undergoing posterior surgeries for cervical OPLL (LAMP: 270 patients, PDF: 110 patients), and investigated the systemic and local complications, including neurological complications. We further evaluated risk factors related to the neurological complications.

RESULTS

Motor palsy was found in 40 patients (10.5%), and motor palsy in the upper extremity was most frequent (8.9%), especially in patients who received PDF (14.5%). Motor palsies involving the lower extremities was found in 6 patients (1.6%). Regarding local complications, dural tears (3.9%) and surgical site infections (2.6%) were common. In the univariate analysis, body mass index, preoperative cervical alignment, fusion surgery, and the number of operated segments were the factors related to motor palsy. Multivariate analysis revealed that fusion surgery and a small preoperative C2-C7 angle were the independent factors related to motor palsy. Motor palsy involving the lower extremities tended to be found at early time points after the surgery, and all the patients fully recovered. Motor palsy in the upper extremities occurred in a delayed manner, and 68.8% of patients with PDF showed good recovery, whereas 81.3% of patients with LAMP showed good recovery.

CONCLUSIONS

In posterior surgeries for cervical OPLL, segmental motor palsy in the upper extremity was most frequently observed, especially in patients who received PDF. Fusion and a small preoperative C2-C7 angle were the independent risk factors for motor palsy.

LEVEL OF EVIDENCE

Level III.

Relationship between cervical curvature and spinal cord drift distance after laminectomy via lateral mass screw fixation and its effect on clinical efficacy

BACKGROUND

Laminectomy with lateral mass screw fixation (LCS) is considered an effective surgical procedure for cervical spondylotic myelopathy. However, varying degrees of loss of the cervical curvature were noted in some patients postoperatively. The aim of this study was to observe the relationship between cervical curvature and spinal drift distance after LCS and to determine its effect on neurological function, axial symptoms, and C5 palsy.

METHODS

A total of 117 consecutive cervical spondylotic myelopathy patients with normal cervical curvature underwent LCS from April 2015 to May 2017 in our institution. Of these patients, 90 patients who accepted to undergo an integrated follow-up were enrolled in this study. The patients were divided into 3 groups based on their postoperative cervical curvature. In group A (28 patients), the cervical curvature became straight postoperatively (0°≤cervical spine angle≤5°); in group B (36 patients), the cervical curvature decreased (5°<cervical spine angle≤16.5°); and in group C (26 patients), the cervical curvature remained normal (cervical spine angle>16.5°). Spinal drift distance, neurological recovery, axial symptoms, and C5 palsy in the patients were recorded and analyzed.

RESULTS

Postoperative measurements showed that there was no significant difference in laminectomy width between the groups (P > .05). The cervical spine angle was 2.7° ± 0.5° in group A, 11.2° ± 2.6° in group B, and 20.8° ± 4.1° in group C (P < .05), while the spinal drift distance was 1.2 ± 0.2 mm, 1.8 ± 0.4 mm, and 3.0 ± 0.5 mm, respectively (P < .05). The postoperative Japanese Orthopedic Association score was significantly increased in all groups (P < .05), and there was no significant difference between the groups at different time points (P > .05). However, significant differences were noted between the groups in axial symptoms (P < .05), which were analyzed via the visual analog scale score. The occurrence of C5 palsy in groups A, B, and C was 7.1% (2/28), 8.3% (3/36), and 11.5% (3/26), respectively (P > .05).

CONCLUSION

In LCS, the cervical curvature should be maintained at the normal angle to obtain a good spinal cord drift distance and a lower incidence of axial symptoms.

C5 palsy after cervical laminectomy: natural history in a 10-year series

BACKGROUND CONTEXT

C5 palsy is a well-known complication following cervical laminectomy, however the cause of this complication remains elusive, with many studies providing conflicting reports on prognosis and the impact of specific risk factors.

PURPOSE

To describe the natural history of and risk factors for C5 palsy after first time cervical laminectomy involving C4 and/or C5, in a large series with a high rate of postoperative palsy.

STUDY DESIGN/SETTING

This is a retrospective case series.

PATIENT SAMPLE

Patients undergoing first time cervical laminectomy for degenerative spine pathologies at a single institution between January 2008 and July 2018. Adult patients were included if a complete laminectomy was performed at C4 or C5 for degenerative pathology and pre- and postoperative upright lateral x-rays were performed.

OUTCOME MEASURES

The primary outcome measure was postoperative C5 palsy, defined as a decrease in strength of at least one point in deltoid and/or biceps within 30 days of operation. The secondary outcome measure was recovery of function.

METHODS

A retrospective database of patients who underwent posterior cervical spine surgery was created and further focused by utilizing specific Common Procedural Technology (CPT) codes associated with our desired patient population. Patients were excluded from our study if they had inadequate pre- and postoperative imaging, as well as patients with a history of prior cervical spine surgery, concurrent anterior surgery, intradural pathology, spinal tumor, or spinal trauma. Patient history, surgical specifics, and neurologic function were recorded.

RESULTS

A total of 190 patients were treated by 13 surgeons. 53 (27.9%) developed C5 palsy postoperatively. Of patients with C5 palsy, 40 (75.5%) recovered to baseline strength, 46 (86.6%) had at least grade 4 strength at last follow up, and 4 (7.5%) had strength worse than baseline and motor grade less than 4. Median time to recovery was 2.0 (IQR: 0.18 to 8.24) months. Age, gender, preoperative motor score, number of levels decompressed, smoking history, and comorbidities were not associated with a significant increase in the odds of C5 palsy. Risk of C5 palsy increased by 35% for every additional level fused below C4.

CONCLUSION

The risk of C5 palsy is increased with instrumentation caudal to C5 in operations addressing degenerative cervical pathology. This should be taken into consideration during operative planning. Overall prognosis of C5 palsy is good; however, incidence of this condition may be greater than previously reported.

Comparison of the surgeries for the ossification of the posterior longitudinal ligament-related cervical spondylosis: A PRISMA-compliant network meta-analysis and literature review

OBJECTIVE

We designed and performed a network meta-analysis to compare the clinical outcomes among the 5 surgeries-anterior cervical corpectomy and fusion (ACCF), anterior controllable antedisplacement fusion (ACAF), laminoplasty (LP), laminectomy (LC), and posterior decompression with instrumented fusion (PDF)-for patients with cervical spondylosis related to the ossification of the posterior longitudinal ligament (OPLL).

METHODS

Databases, including PubMed, EMBASE, Cochrane Library, Google Scholar, and Web of Science (firstly available-2019) were selected for literature search. We performed a network meta-analysis with the included studies. A Newcastle-Ottawa scale was employed to assess the study quality of the included studies.

RESULTS

Total 23 studies with 1516 patients were included in our analysis. We found that ACCF achieved the most improvement in the Japanese Orthopaedic Association Scores and excellent and good recovery rate, ACAF achieved the best improvement of the improvement rate and lordosis. LP got the best operative time and blood loss.

CONCLUSIONS

Our results suggested that both anterior (ACCF and ACAF) and posterior (LP, LC, and PDF) procedures have their strengths and weaknesses. Clinicians need to select the most appropriate surgery with a comprehensive consideration of the clinical condition of each patient with OPLL-related cervical spondylosis.

Comparative Effectiveness and Safety of Anterior Cervical Corpectomy with Fusion, Laminoplasty, and Laminectomy and Instrumented Fusion for Ossification of the Posterior Longitudinal Ligament: A Systematic Review and Network Meta-Analysis

BACKGROUND

To evaluate the comparative effectiveness and safety of anterior cervical corpectomy with fusion (ACCF), laminoplasty (LP), and laminectomy and instrumented fusion (LF) in the treatment of ossification of the posterior longitudinal ligament (OPLL).

METHODS

Embase, Pubmed, and Cochrane library were searched from their date of inception to June 13, 2020. Relevant randomized controlled trials (RCTs) and cohort studies comparing different procedures among ACCF, LP, and LF were identified, data were extracted to perform a network meta-analysis (NMA). The outcomes were the Japanese Orthopedic Association (JOA) score and complications.

RESULTS

We deemed 14 trials eligible, including 877 patients. In NMA, ACCF showed a significant improvement of JOA score compared with LP [MD= -0.89, 95% CI (-1.73, -0.18)], but no significant difference was found when compared LF with ACCF or LP. No significant differences in complications were found when compared LF with LP or ACCF, while ACCF showed significantly higher in complications than LP [OR = 1.99, 95% CI (1.10, 3.35)]. The surface under the cumulative ranking curves (SUCRA) showed that the rank of JOA score improvement is as follows: ACCF (82.5%), LF (79.5%), and LP (2.3%). And the rank of complication rate is as follows: LF (65.8%), ACCF (68.4%), and LP (2.1%).

LIMITATION

The biggest limitation was that none of the included studies were RCTs.

CONCLUSIONS

Despite the higher probability of complications than LP, ACCF was the more recommended procedure for its highest ranking spectrums of JOA score improvement to treat the OPLL.

Tensile mechanical analysis of anisotropy and velocity dependence of the spinal cord white matter: a biomechanical study

In spinal cord injuries, external forces from various directions occur at various velocities. Therefore, it is important to physically evaluate whether the spinal cord is susceptible to damage and an increase in internal stress for external forces. We hypothesized that the spinal cord has mechanical features that vary under stress depending on the direction and velocity of injury. However, it is difficult to perform experiment because the spinal cord is very soft. There are no reports on the effects of multiple external forces. In this study, we used bovine spinal cord white matter to test and analyze the anisotropy and velocity dependence of the spinal cord. Tensile-vertical, tensile-parallel, shear-vertical, and shear-parallel tests were performed on the white matter in the fibrous direction (cranial to caudal). Strain rate in the experiment was 0.1, 1, 10, and 100/s. We calculated the Young's modulus of the spinal cord. Results of the tensile and shear tests revealed that stress tended to increase when external forces were applied parallel to the direction of axon fibers, such as in tensile-vertical and shear-vertical tests. However, external forces those tear against the fibrous direction and vertically, such as in tensile-parallel and shear-parallel tests, were less likely to increase stress even with increased velocity. We found that the spinal cord was prone to external forces, especially in the direction of the fibers, and to be under increased stress levels when the velocity of external forces increased. From these results, we confirmed that the spinal cord has velocity dependence and anisotropy. The Institutional Animal Care and Use Committee of Yamaguchi University waived the requirement for ethical approval.

Surgical decision-making for ossification of the posterior longitudinal ligament versus other types of degenerative cervical myelopathy: anterior versus posterior approaches

Background

The debate between anterior or posterior approach for pathologies such as cervical spondylotic myelopathy (CSM) and ossification of the posterior longitudinal ligament (OPLL) have drawn heated debate but are still inconclusive.

Main body of the abstract

A narrative review was performed specifically to study the differences pertaining to OPLL and other causes of degenerative cervical myelopathy (DCM). Current evidence suggests that anterior approach is preferred for K-line (−) OPLL, K-line (+) with canal occupying ratio > 60% and DCM with pre-existing cervical kyphosis. Posterior approach is preferred for K-line (+) OPLL with canal-occupying ratio < 50–60%, and multi-level CSM. No particular advantage for either approach was observed for DCM in a lordotic cervical spine. Anterior approach is generally associated with more complications and thus needs to be weighed carefully during decision-making. The evidence is not convincing for comparing single versus multi-level involvement, and the role of patients' co-morbidity status, pre-existing osteoporosis and co-existent spinal pathologies in influencing patient outcome and surgical options. This should be a platform for future research directives.

Conclusion

From this review, evidence is still inconclusive but there are some factors to consider, and DCM and OPLL should be considered separately for decision-making. Anterior approach is considered for pre-existing cervical kyphosis in DCM, for K-line (−) regardless of canal-occupying ratio, and K-line (+) and canal-occupying ratio > 60% for OPLL patients. Posterior approach is considered for patients with multi-level pathology for DCM, and K-line (+) and canal-occupying ratio < 50–60% for OPLL.

Mid-term Surgical Outcome of Posterior Decompression With Instrumented Fusion in Patients With K-line (-) Type Cervical Ossification of the Posterior Longitudinal Ligament With a 5-Year Minimum Follow-up

STUDY DESIGN

A retrospective case-control study.

OBJECTIVE

The objective of this study was to assess mid-term surgical outcomes after posterior decompression with instrumented fusion (PDF) in patients with K-line (-) type cervical ossification of the posterior longitudinal ligament (OPLL).

SUMMARY OF BACKGROUND DATA

The poor surgical outcome for K-line (-) type cervical OPLL can result from posterior decompression alone.

MATERIALS AND METHODS

We reviewed cases of K-line (-) type cervical OPLL in 24 patients who underwent PDF in our institute from 2002 to 2014. As a control, we used K-line (-) type cervical OPLL in 9 patients who underwent laminoplasty before 2002 (LMP group). The neurological status and radiographic findings were evaluated retrospectively.

RESULTS

The preoperative Japanese Orthopedic Association score was 7.9±2.4 points in the PDF group and 7.4±2.3 points in the LMP group (P=0.584). The postoperative Japanese Orthopedic Association score was 11.7±2.6 points in the PDF group and 9.2±2.0 points in the LMP group at a 5-year follow-up (P=0.008). The recovery rate on average was 39.0% in the PDF group and 14.9% in the LMP group at a 5-year follow-up (P=0.037). The range of motion postoperatively at the maximal spinal cord compression level decreased significantly in the PDF group. The C2-C7 angle was 2.7 degrees of kyphosis in the PDF group, whereas 5.5 degrees of kyphosis was found in the LMP group at a 5-year follow-up (P=0.303). The center of gravity of the head-C7 sagittal vertical axis was 40 mm in the PDF group and 43 mm in the LMP group (P=0.936).

CONCLUSIONS

The relatively good surgical outcome could be obtained by PDF for patients with K-line (-)-type cervical OPLL. The addition of posterior instrumented fusion eliminated the dynamic factor at the level of maximal spinal cord compression.

LEVEL OF EVIDENCE

Level IV.

A new concept of motion preservation surgery of the cervical spine: PEEK rods for the posterior cervical region

BACKGROUND

Laminectomy may cause kyphotic postoperative deformity in the cervical region leading to segmental instability over time. Laminoplasty may be an alternative procedure to laminectomy, as it protects the spine against post-laminectomy kyphosis; however, similar to laminectomy, laminoplasty may cause sagittal plane deformities by destructing or weakening the dorsal tension band.

OBJECTIVE

Using finite element analysis (FE), we attempted to determine whether a posterior motion preservation system (PEEK posterior rod system concept) could overcome the postoperative complications of laminectomy and laminoplasty and eliminate the side effects of rigid posterior stabilization in the cervical region.

METHODS

We compared PEEK rods in four different diameters with a titanium rod for posterior cervical fixation. The present study may lead to motion preservation systems of the cervical vertebra.

RESULTS

When PEEK rod is compared with titanium rod, considerable increase in range of motion is observed.

CONCLUSIONS

PEEK rod-lateral mass screw instrumentation systems may be useful in motion preservation surgery of the posterior cervical region.

The relationship between preoperative cervical sagittal balance and clinical outcome of laminoplasty treated cervical ossification of the posterior longitudinal ligament patients

BACKGROUND CONTEXT

Laminoplasty is a common surgical method used to treat patients with cervical ossification of the posterior longitudinal ligament (OPLL). Although laminoplasty is preferred over traditional laminectomy, the factors affecting the complications and outcomes are unclear. Recently, sagittal balance indexes have been revealed to be predictors of clinical outcomes in patients with cervical degenerative diseases, but their relationships with laminoplasty-treated OPLL outcomes remains unknown.

PURPOSE

The purpose of this study is to evaluate the relationship of preoperative cervical sagittal balance indexes and clinical outcome in laminoplasty treated OPLL patients.

STUDY DESIGN

This is a retrospective case study.

PATIENT POPULATION

Between January 2015 and January 2017, 181 consecutively included patients who underwent cervical laminoplasty for OPLL were enrolled (male:female ratio=126:75; mean age=60.2 years). Cervical spine lateral radiographs in neutral, flexion, and extension positions were taken before and 2 years after the surgery.

OUTCOME MEASURES

The C2-C7 Cobb angle, T1 slope, C1-C7 sagittal vertical axis (SVA), C2-C7 SVA, CGH (center of gravity of the head)-C7 SVA, cervical JOA (Japanese Orthopedic Association) score, and neck VAS (visual analogue scale) score were measured preoperatively and postoperatively at the 2-year follow-up.

METHODS

The patients were divided into two groups according to changes in the lordotic angle or the recovery rate of the JOA score. The relationships between the postoperative lordosis loss or the clinical outcome and the preoperative variables, including the patient's age, JOA score, C2-C7 Cobb angle, T1 slope, C1-C7 SVA, C2-C7 SVA, and CGH-C7 SVA, were investigated.

RESULTS

The patients were divided into two groups according to the postoperative change in the C2-C7 Cobb angle. There were no differences in the age, preoperative C2-C7 Cobb angle, C1-C7 SVA, or C2-C7 SVA; there was only a difference in the preoperative CGH-C7 SVA and T1 slope level (p=.038, p=.042). The postoperative JOA and JOA recovery rate were related to the postoperative lordosis loss in cervical alignment (p=.048, p=.031). We again divided the patients into two groups according to the JOA recovery rate and found that only the preoperative CGH-C7 SVA and C1-C7 SVA were related to the neurological outcome (p=.011, p=.047). According to the multivariate logistic regression analysis, higher preoperative CGH-C7 SVA levels were significantly associated with decreases in the lordosis angle postoperatively and the clinical outcome (p=.018, OR=1.225; p=.034, OR=1.654). The ROC (receiver operating characteristic) analysis revealed that the proper cutoff value of preoperative CGH-C7 SVA for predicting the postoperative loss of lordosis and clinical outcomes is 3.8 cm.

CONCLUSION

Preoperative cervical sagittal balance indexes are related to the outcomes of OPLL patients after laminoplasty. Patients with high preoperative CGH-C7 SVA levels have a high probability of developing sagittal imbalances and neurological symptoms of the cervical spine, and this measurement can be used as a predictor of outcomes in laminoplasty-treated cervical OPLL patients.

Progression of Cervical Ossification of Posterior Longitudinal Ligament After Laminoplasty or Laminectomy With Posterior Fixation

STUDY DESIGN

Retrospective case analysis.

OBJECTIVE

This study was conducted to investigate the course of ossification of the posterior longitudinal ligament (OPLL) progression after laminoplasty (LP) or laminectomy with posterior fixation (PF).

SUMMARY OF BACKGROUND DATA

LP is now recognized as a standard technique for the treatment of cervical multisegment OPLL; however, PF is beneficial for patients with severe stenosis. In recent years, there has been increasing interest in mechanical stress in OPLL, which is assumed to significantly impact progression.

METHODS

The progression of OPLL was assessed using midline sagittal computed tomography images of the cervical spine at various follow-up points. Radiographic parameters including the C2-C7 Cobb angle, C2-C7 range of motion (ROM), and adjacent cranial and caudal segmental ROMs were measured. Postoperative changes and differences between the LP and PF groups in the radiographic parameters were calculated to assess biomechanical stress. Logistic regression analysis was used to analyze the risk factors affecting the progression rate.

RESULTS

The authors included 14 PF and 36 LP patients, with a mean follow-up period of 28.9±20.8 and 37.6±16.8 months, respectively (P=0.069). After surgical treatment, both groups showed loss of cervical lordosis (9.2±6.9 vs. 5.3±8.2 degrees, P=0.220) and C2-C7 ROM (14.6± 13.5 vs. 13.1±12.2 degrees, P=0.861). The decrease of ROM in the cranial adjacent segment was larger in the LP group than in the PF group (0.7±4.1 vs. 1.4±5.5 degrees, P=0.453). The ROM in the caudal adjacent segment decreased in the LP group but increased in the PF group (-1.4±6.2 vs. 2.6±5.1 degrees, P=0.041). The progression rate was 2.15±1.31 mm/mo in the PF group and 1.53±1.04 mm/mo in the LP group (P=0.041). PF showed an odds ratio of 12.917 for a higher progression rate (95% confidence interval, 1.397-119.443; P=0.024).

CONCLUSION

The rate of progression of cervical OPLL was significantly higher after PF than after LP.Level III-a retrospective analysis.

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

BACKGROUND CONTEXT

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

PURPOSE

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

STUDY DESIGN/SETTING

Systematic review and meta-analysis.

PATIENT SAMPLE

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

OUTCOME MEASURES

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Ossification of the Posterior Longitudinal Ligament: Surgical Approaches and Associated Complications

Ossification of the posterior longitudinal ligament (OPLL) is a rare but potentially devastating cause of degenerative cervical myelopathy (DCM). Decompressive surgery is the standard of care for OPLL and can be achieved through anterior, posterior, or combined approaches to the cervical spine. Surgical correction of OPLL via any approach is associated with higher rates of complications and the presence of OPLL is considered a significant risk factor for perioperative complications in DCM surgeries. Potential complications include dural tear (DT) and subsequent cerebrospinal fluid leak, C5 palsy, hematoma, hardware failure, surgical site infections, and other neurological deficits. Anterior approaches are technically more demanding and associated with higher rates of DT but offer greater access to ventral OPLL pathology. Posterior approaches are associated with lower rates of complications but may allow for continued disease progression. Therefore, the decision to pursue either an anterior or posterior approach to surgical decompression may be critically influenced by complications associated with each procedure. The authors critically review anterior and posterior approaches to surgical decompression of OPLL with particular focus on the complications associated with each approach. We also review the recent work in developing new surgical treatments for OPLL that aim to reduce complication incidence.

Does Ossification of the Posterior Longitudinal Ligament Progress After Fusion?

Starting in the 1960s, ossification of the posterior longitudinal ligament (OPLL) became more commonly diagnosed in Japan. The disease is characterized by a gradual increase in calcification of the posterior longitudinal ligament with the eventual sequelae of cervical canal stenosis and myelopathy. Surgical interventions to relieve stenosis and neurologic symptoms are performed to decompress the cervical canal. Studies demonstrate continued ossification of the OPLL in both nonsurgical and surgically treated patients. In this review, the authors evaluate the epidemiology, pathophysiology, and literature regarding disease progression in OPLL after cervical fusion.

Clinical efficacy of laminectomy with instrumented fixation in treatment of adjacent segmental disease following ACCF surgery: a retrospective observational study of 48 patients

This study was designed to investigate the clinical efficacy of laminectomy with instrumented fixation in treatment of adjacent segmental diseases following anterior cervical corpectomy and fusion (ACCF) surgery. Between January 2008 and December 2015, 48 patients who underwent laminectomy with instrumented fixation to treat adjacent segmental diseases following ACCF surgery, were enrolled into this study. The patients were followed up at least 2 years. Pain assessment was determined by visual analogue scale (VAS) score and Neck Disability Index (NDI) score; neurological impairment was evaluated by Japanese Orthopaedic Association (JOA) score; and radiographic parameters were also compared. All comparisons were determined by paired t test with appropriate Bonferronni correction. VAS score preoperatively and at last follow-up was 5.28 ± 2.35 vs 1.90 ± 1.06 (P < 0.001). JOA score preoperatively and at last follow-up was 8.2 ± 3.6 vs 14.5 ± 1.1 (P < 0.001). NDI score preoperatively and at last follow-up was 30.5 ± 12.2 vs 10.6 ± 5.8 (P < 0.001). Moreover, the losses of cervical lordosis and C2-C7 range of motion after laminectomy were significant (both P < 0.005), but not sagittal vertical axis distance. Postoperative complications were few or mild. In conclusion, clinical effectiveness and safety can be guaranteed when the patients undergo laminectomy with instrumented fixation to treat adjacent segmental diseases following ACCF surgery.

Comparison of laminectomy and fusion vs laminoplasty in the treatment of multilevel cervical spondylotic myelopathy: A meta-analysis

PURPOSE

The purpose of this study is to evaluate the clinical safety and efficacy between laminectomy and fusion (LF) versus laminoplasty (LP) for the treatment of multi-level cervical spondylotic myelopathy (CSM).

METHODS

The authors searched electronic databases using PubMed, MEDLINE, Embase, Cochrane Controlled Trial Register, and Google Scholar for relevant studies that compared the clinical effectiveness of LF and LP for the treatment of patients with multilevel CSM. The following outcome measures were extracted: the Japanese Orthopaedic Association (JOA) scores, cervical curvature index (CCI), visual analog scale (VAS), Nurich grade, reoperation rate, complications, rate of nerve palsies. Newcastle Ottawa Quality Assessment Scale (NOQAS) was used to evaluate the quality of each study. Data analysis was conducted with RevMan 5.3.

RESULTS

A total of 14 studies were included in our meta-analysis. No significant difference was observed in terms of postoperative Japanese Orthopaedic Association score (P = .29), visual analog scale neck pain (P = .64), cervical curvature index (P = .24), Nurich grade (P = .16) and reoperation rate (P = .21) between LF and LP groups. Compared with LP group, the total complication rate (OR 2.60, 95% CI 1.85, 3.64, I = 26%, P < .00001) and rate of nerve palsies (OR 3.18, 95% CI 1.66, 6.11, I = 47%, P = .0005) was higher in the LF group.

CONCLUSIONS

Our meta-analysis reveals that surgical treatments of multilevel CSM are similar in terms of most clinical outcomes using LF and LP. However, LP was found to be superior than LF in terms of nerve palsy complications. This requires further validation and investigation in larger sample-size prospective and randomized studies.

Posterior percutaneous full-endoscopic cervical laminectomy and decompression for cervical stenosis with myelopathy: a technical note

PURPOSE

Cervical stenosis with myelopathy caused by ossification of the ligamentum flavum is relatively rare, and surgical treatment is the preferred option. Previous surgical procedures usually require assisted internal fixation, while some problems may occur, such as large trauma, intraoperative bleeding, wound infection and internal fixation failure. The aim of this paper is to introduce a new minimally invasive surgical procedure for the treatment of upper cervical spinal stenosis complicated with myelopathy.

METHODS AND RESULTS

A 56-year-old male patient with cervical myelopathy (C2-3) caused by calcification of the ligamentum flavum underwent posterior percutaneous full-endoscopic cervical laminectomy and decompression (PECLD) and achieved a good clinical efficacy. A surgical incision just 1 cm in size was made, and there was little bleeding during the operation. The patient was hospitalized for 2 days and returned to work after 4 weeks. The patient's postoperative recovery of neurological function was significantly improved, the pain was obviously reduced, and the quality of life was remarkably improved. No intra- or postoperative surgical complications were encountered.

CONCLUSIONS

PECLD is an effective method for treating cervical stenosis associated with myelopathy due to ossification of the ligamentum flavum. It has the advantages of smaller trauma, less bleeding, shorter postoperative hospital stays and faster recovery. Taken together, this minimally technique can be considered as a good alternative to traditional open surgery.