Laminoplasty plate design is an independent risk factor for facet joint violation.

The aim of this study was to determine whether the sagittal lordotic alignment, clinical outcomes and axial symptoms (AS) could be improved by kyphotic correction through the posterior approach for the treatment of multilevel cervical degenerative myelopathy (CDM) and to further analyze the changes of cervical spinal alignment parameters after correction of kyphosis. The hypothesis was that correction of kyphosis can improve the severity of AS and neurological recovery. We retrospectively reviewed 109 patients who suffered from multilevel CDM combined with kyphosis. The patients had undergone open-door laminoplasty (Group LP, 53 patients) and laminectomy with instrumentation (Group LI, 56 patients) between January 2014 and December 2018. Cervical spinal alignment parameters, including curvature index (CI), T1 slope, C2-7 Cobb angle, C2-7 SVA, were measured on the pre- and postoperative lateral radiographs. The recovery rate was calculated based on the Japanese Orthopedic Association (JOA) score. AS severity was quantified using Neck Disability Index (NDI). A P value less than 0.05 was considered to be significant. Analyses of postoperative follow-up data showed significant differences (P < 0.001) in CI, correction of CI, C2-7 Cobb angle, T1 slope, C2-7 SVA and NDI between Group LP and LI, but no significant differences in JOA score (P = 0.23) and recovery rate (P = 0.13). There were significant differences (P < 0.001) in CI, T1 slope, C2-7 Cobb angle, C2-7 SVA, JOA score, and NDI between pre- and postoperative follow-up in both groups. Correction of CI showed negative correlation with AS severity (r = -0.51, P < 0.001), and no association with recovery rate (r = 0.14, P = 0.15). Satisfied neurological improvement was achieved by LP and LI for multilevel CDM combined with kyphosis. Cervical kyphotic correction produced significant improvement of AS and increase of T1 slope and C2-7 SVA. However, the kyphotic correction may not be associated with better neurological recovery in the short-term postoperative period.

Cervical alignment and clinical outcome of anterior cervical discectomy and fusion vs. anterior cervical corpectomy and fusion in local kyphotic cervical spondylotic myelopathy

ObjectivePosterior open-door laminoplasty (PODL) is a common procedure for treating multilevel cervical spondylotic myelopathy (MCSM). Little information is available regarding the cervical sagittal balance and surgical efficacy of PODL when securing with different methods. Therefore, this study aims to investigate the clinical outcomes and the changes in cervical sagittal parameters and balance associated with PODL secured with titanium miniplates vs anchors.MethodA retrospective analysis was performed on the clinical data of 79 patients with MCSM who were treated in our institution from January 2015 to December 2016. Among them, 42 patients were treated by PODL secured with titanium miniplates (group A) and 37 patients by PODL secured with anchors (group B). Surgical time, intraoperative blood loss, hospital stay, hospitalized cost, VAS scores of neck pain, JOA scores, neck disability index (NDI), and improvement rate of spinal neurological function (IRNF) were recorded before surgery and at 12 months after surgery. Before surgery, at 1 month and 2 years after surgery, the following radiological parameters were recorded and compared on the lateral cervical X-ray images: the distance from the vertical axis of C2 sagittal plane to the posterior superior edge of C7 (C2-7 SVA), the inclusion angle of tangent between C2 and C7 trailing edge (C2-7 Cobb angle), and the intersection angle between the upper edge of T1 and the horizontal line (T1 Slope).ResultComparing the two groups, there were no significant differences in surgical time, intraoperative blood loss, hospital stay, VAS, JOA, and NDI scores before surgery (P > 0.05); however, the hospitalized cost of group A were much higher than those of the group B (P < 0.05). At 2 years after surgery in the two groups, there was a significant reduction in VAS and NDI scores (P < 0.05), and JOA scores increased significantly (P < 0.05). In addition, there were no significant differences in VAS, JOA and IRNF between the two groups (P > 0.05); however, NDI scores of group A were better than those of group B (P < 0.05). In radiological parameters, before surgery, the two groups showed no significant differences in C2-7 SVA, C2-7 Cobb angle, and T1 slope (P > 0.05); however, after surgery, C2-7 SVA and T1 slope increased (P < 0.05), while C2-7 Cobb angle decreased (P < 0.05). At 2 years after surgery, the two groups did not differ significantly in C2-7 Cobb angle and T1 slope (P > 0.05), while C2-7 SVA of group A was superior to that of group B (P < 0.05). The difference value of C2-7 SVA measured before and after surgery was correlated negatively with that of NDI scores (P < 0.05).ConclusionPODL secured with titanium miniplates or anchors achieved good clinical efficacy in the treatment of MCSM. However, the patients with miniplates feel a better cervical functional status, while those with anchors spend less on hospitalization. Both methods lead to anteversion of cervical spine, but cervical sagittal balance after miniplates is better than that of anchors.

Objective To investigate the impact of C2 vertebral instability on the sagittal parameters of the cervical spine and the clinical efficacy after cervical laminoplasty with unilateral open-door cervical expansive laminoplasty (EMOL). Methods In a retrospective analysis of 18 patients with cervical 2 vertebral instability from August 2017 to August 2021 in the second Affiliated Hospital of Naval Military Medical University and the Six Affiliated Hospital of Xinjiang Medical University treated with single open-door vertebroplasty (C3-6 or C3-7), 36 patients with stable cervical 2 cervical EMOL during the same period (control group). To evaluate the changes in sagittal parameters before and after surgery in the two groups, including C0-2 Cobb angle, C2-7 sagittal axis distance (sagittal vertical axis, SVA), C2-7 Cobb angle, T1 tilt angle (T1-Sl); The postoperative outcome was evaluated using the visual analogue score for neck and shoulder pain (visual analog scale, VAS) and the Japan Society Cervical Function Score (Japanese 0rthopaedic Association, JOA). Results Compared to preoperative values, both the observation group and the control group showed significant improvement in postoperative VAS scores and JOA scores. The JOA scores were 14.0 ± 1.6 and 13.1 ± 1.6, with improvement rates of 68.42% and 58.06%, respectively, compared to their respective preoperative scores. However, there was no significant difference between the two groups. The observation group had significantly greater cervical range of motion (ROM) before surgery compared to the control group ( p &amp;lt; 0.05). At the last follow-up, the observation group showed a significant decrease in C2-7 Cobb angle from preoperative (8.2 ± 2.5)° to (5.1 ± 2.5)° ( p &amp;lt; 0.05). Cervical ROM decreased from preoperative (39.8 ± 3.6)° to (31.6 ± 4.5)° ( p &amp;lt; 0.05). C0-2 Cobb angle increased from preoperative (22.0 ± 3.7)° to (25.8 ± 3.1)° ( p &amp;lt; 0.05). C2-7 SVA increased from preoperative (−19.6 ± 3.4)° to (−15.8 ± 3.7)° ( p &amp;lt; 0.05). However, there was no significant change in T1 slope at the last follow-up ( p &amp;gt; 0.05). The observation group showed a decrease in C2 vertebral displacement from preoperative (4.5 ± 0.9) mm to (3.3 ± 0.5) mm ( p &amp;lt; 0.05), while the C2/3 angle showed no significant change compared to preoperative values ( p &amp;gt; 0.05). In both groups, postoperative follow-up showed a significant increase in C0-2 Cobb angle and C2-7 SVA, a non-significant difference in T1 slope, and a significant decrease in C2-7 Cobb angle and cervical ROM compared to preoperative values. However, there were no significant differences between the two groups in the above-mentioned parameters ( p &amp;gt; 0.05). Conclusion C2 vertebral instability does not affect the sagittal parameters and efficacy of cervical laminoplasty with EMOL. EMOL surgery for cervical myelopathy with C2 vertebral instability is effective and reliable, without exacerbating C2 vertebral instability. Furthermore, it maintains good sagittal balance of the cervical spine.

BackgroundCervical 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.MethodsA 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).

PurposeThis study aimed to compare cervical sagittal parameters and clinical outcomes between patients undergoing cervical laminoplasty(CL) and those undergoing lateral mass screw fixation(LMS).MethodsWe retrospectively studied 67 patients with multilevel ossification of the posterior longitudinal ligament (OPLL) of the cervical spine who underwent lateral mass screw fixation (LMS = 36) and cervical laminoplasty (CL = 31). We analyzed cervical sagittal parameters (C2-7 sagittal vertical axis (C2-7 SVA), C0-2 Cobb angle, C2-7 Cobb angle, C7 slope (C7s), T1 slope (T1s), and spino-cranial angle (SCA)) and clinical outcomes (visual analog scale [VAS], neck disability index [NDI], Japanese Orthopaedic Association [JOA] scores, recovery rate (RR), and minimum clinically significant difference [MCID]). The cervical sagittal parameters at the last follow-up were analyzed by binary logistic regression. Finally, we analyzed the correlation between the cervical sagittal parameters and each clinical outcome at the last follow-up after surgery in both groups.ResultsAt the follow-up after posterior decompression in both groups, the mean values of C2-C7 SVA, C7s, and T1s in the LMS group were more significant than those in the CL group (P ≤ 0.05). Compared with the preoperative period, C2-C7 SVA, T1s, and SCA gradually increased, and the C2-C7 Cobb angle gradually decreased after surgery (P < 0.05). The improvement in the JOA score and the recovery rate was similar between the two groups, while the improvement in the VAS-N score and NDI score was more significant in the CL group (P = 0.001; P = 0.043). More patients reached MCID in the CL group than in the LMS group (P = 0.036). Binary logistic regression analysis showed that SCA was independently associated with whether patients reached MCID at NDI postoperatively. SCA was positively correlated with cervical NDI and negatively correlated with cervical JOA score at postoperative follow-up in both groups (P < 0.05); C2-7 Cobb angle was negatively correlated with cervical JOA score at postoperative follow-up (P < 0.05).ConclusionCL may be superior to LMS in treating cervical spondylotic myelopathy caused by OPLL. In addition, smaller cervical SCA after posterior decompression may suggest better postoperative outcomes.

Objective: To examine the clinical effect of the enlarged anterior cervical intervertebral cone-shape decompression and fusion(EACDF) for treating degenerative cervical kyphosis (DCK). Methods: This study is a retrospective case series research. From September 2018 to September 2023, the data of 51 patients with DCK who underwent EACDF at Department of Orthopaedics, the Second Affiliated Hospital, Naval Medical University were analyzed retrospectively. Among the 51 patients, there were 28 males and 23 females, with an age of (61.6±9.8) years old (range:39 to 74 years), and an body mass index of (25.9±2.7) kg/m2 (range:20.7 to 31.7 kg/m2). Patients underwent EACDF with expanded decompression by distracted intervertebral space, partial resections of posterior edge of vertebral body and uncinate vertebral joint. The operation duration, blood loss and length of hospital stay were recorded. The visual analog scale (VAS) of neck pain and arm pain, cervical disability index (NDI), and modified Japanese Orthopaedic Association (mJOA) score were recorded in patients before and immediately after surgery, as well as at follow-up. Imaging parameters such as C2-7 Cobb angle of cervical global curvature, Cobb angle at the operative segment, C2-7 sagittal vertical axis (C2-7 SVA), T1 slope and the height of operative segment were measured. The fusion rate and surgical complications of two groups were recorded. Fourty-five patients who underwent anterior cervical corpectomy with fusion (ACCF) during the same period were included to compare the effectiveness of deformity correction between the two groups. Repeated measures ANOVA was used for intra group data comparison and Dunnett-t test was used for pairwise comparison, and mixed design ANOVA was used for inter group data comparison. Results: All patients were successfully completed the operation. The follow-up period after surgery was (40.4±13.4) months (range:12 to 72 months). The neck pain and arm pain VAS, NDI and JOA in the two groups immediately after surgery, at 2 months, 12 months after surgery, and the final follow-up were significantly improved compared with those before operation (all P<0.05). In both groups, postoperative the C2-7 Cobb angle, Cobb angle at the operative segment, C2-7 SVA, T1 slope, and height of operative segment were significantly improved immediately after surgery, at 2 months, 12 months, and the final follow-up (all P<0.05). The C2-7 Cobb angle, Cobb angle at the operative segment, and height of operative segment immediately after surgery, at 2 months, 12 months, and the final follow-up in the EACDF group were significantly higher than those in the ACCF group (all P<0.05). There were no significant differences in C2-7 SVA and T1 slope between the two groups(all P>0.05). At the final follow-up, the angle of every intervertebral space correction in the EACDF group was (9.3±1.6) °(range:6.5° to 12.3°), while in the ACCF group was (3.1±1.8) °(range:1.2° to 5.6°), with a significant difference between the two groups (P<0.05). Patients at the both groups got bone graft fusion at the final follow-up. Conclusions: The clinical effect of EACDF for treating DCK is satisfactory. EACDF maybe superior to ACCF in restoring intervertebral height, correcting and maintaining cervical curvature.

To determine whether radiological, clinical, and demographic findings in patients with cervical spondylotic myelopathy (CSM) were independently associated with loss of cervical lordosis (LCL) after laminoplasty. The prospective study included 41 consecutive patients who underwent laminoplasty for CSM. The difference in C2-7 Cobb angle between the postoperative and preoperative films was used to evaluate change in cervical alignment. Age, sex, body mass index (BMI), smoking history, preoperative C2-7 Cobb angle, T1 slope, C2-7 range of motion (C2-7 ROM), C2-7 sagittal vertical axis (C2-7 SVA), and cephalad vertebral level undergoing laminoplasty (CVLL) were assessed. Data were analyzed using Pearson and Spearman correlation test, and univariate and stepwise multivariate linear regression. T1 slope, C2-7 SVA, and CVLL significantly correlated with LCL (P<0.001), whereas age, BMI, and preoperative C2-7 Cobb angle did not. In multiple linear regression analysis, higher T1 slope (B=0.351, P=0.037), greater C2-7 SVA (B=0.393, P<0.001), and starting laminoplasty at C4 level (B=-7.038, P<0.001) were significantly associated with higher postoperative LCL. Cervical alignment was compromised after laminoplasty in patients with CSM, and the degree of LCL was associated with preoperative T1 slope, C2-7 SVA, and CVLL.

A cross-sectional study. To investigate the correlation of cervical spine alignment changes with aging in asymptomatic population. Previous studies demonstrated the influence of lumbar and thoracic spine on cervical spine alignment, but few has reported the cervical spine alignment change along with aging in asymptomatic population. Asymptomatic population were divided into four groups according to different ages (Group A: ≤20years; Group B: 21-40years; Group C: 41-60years; Group D: ≥61years). Each group was composed of 30 subjects. The following parameters were measured: C0-1 Cobb angle, C1-2 Cobb angle, C2-7 Cobb angle, C1-7 sagittal vertical axis (C1-7 SVA), C2-7 SVA, central of gravity to C7 sagittal vertical axis (CG-C7 SVA), Thoracic Inlet Angle (TIA), Neck Tilt (NT), cervical tilt, cranial tilt, T1 slope (TS), TS-CL, and ANOVA statistical method was used to analyze the differences among four groups, and then, linear regression analysis was performed to analyze correlation of the cervical spine alignment with the aging. C1-7 SVA, C2-7 SVA, CG-C7 SVA, TIA, NT, TS, and cranial tilt were found statistically different among four groups (P<0.01). From Group A to Group D, the mean C1-7 SVA were 30.7, 26.0, 21.8, and 36.9mm, the mean C2-7 SVA were 18.7, 14.7, 11.9, and 24.7mm, and the mean CG-C7 SVA were 19.6, 16.6, 9.4, and 26.7mm. The mean TIA were 62.4°, 65.0°, 71.8°, and 76.9°, the mean NT were 39.4°, 43.8°, 46.3°, and 48.2°, the mean TS were 23.0°, 21.1°, 25.5°, and 28.7°, and the mean cranial tilt were 5.7°, 4.8°, 3.0°, and 9.5°. Further linear regression indicated that TIA (r=0.472; P<0.0001), NT (r=0.337; P=0.0006), and TS (r=0.299; P=0.0025) were positively correlated with aging. A gradual increase of TIA, NT, and TS, accompanied with an increased CL, is found along with aging in asymptomatic population, among which TIA, NT, and TS are significantly correlated with physiological nature of aging.

Retrospective study. The preoperative parameters for predicting the loss of lordosis after cervical laminoplasty were investigated in the present study. Cervical laminoplasty is an effective surgical method to decompress the cervical spinal cord. Maintaining cervical lordosis after laminoplasty is an important factor to ensure the successful surgical treatment. To know the preoperative parameters for predicting loss of lordosis after cervical laminoplasty is important for better outcome after laminoplasty. In this retrospective study, 106 patients who underwent cervical laminoplasty from 2011 to 2015 were reviewed. The preoperative parameters; T1 slope (TS), Cobb lordotic angle (CLA) and sagittal vertical axis (SVA) at C2-C7, relative cross-sectional area (RCSA), and fatty degeneration of deep extensor muscles (DEMs) were measured. Visual analogue scale (VAS) and modified Japanese Orthopedic Association (mJOA) scores were used for clinical assessment. Correlation analysis was performed between the postoperative CLA change and preoperative parameters. The patients were divided into the decreased- or maintained-lordosis groups based on the difference between postoperative and preoperative CLA. All preoperative parameters were compared between groups. Based on correlation analysis, preoperative TS (P = 0.001), TS-CLA (P = 0.046), RCSA at C7-T1 (P < 0.001), and fatty degeneration of DEMs (P < 0.001) were correlated with loss of lordosis. Among the 106 patients, 68 showed decreased-lordosis and 38 maintained-lordosis. Preoperative TS (P = 0.003), SVA (P = 0.014), TS-CLA (P = 0.015), and RCSA at C7-T1 (P = 0.005) were significantly different between groups. In both correlation and comparative analyses, higher TS and TS-CLA and less RCSA at C7-T1 were associated with loss of lordosis. Neck pain VAS (P < 0.001) and mJOA scores (P < 0.001) were significantly improved in the maintained-lordosis group. Maintaining cervical lordosis is important for clinical outcomes after laminoplasty. Preoperative higher TS, TS-CLA, and less RCSA at C7-T1 were considered as predictors for loss of lordosis. These characteristics should be considered when choosing the surgical method to help maintain cervical lordosis. 3.

Relationship of T1 slope with loss of lordosis and surgical outcomes after laminoplasty for cervical ossification of the posterior longitudinal ligament

Prediction of angular kyphosis after cervical laminoplasty using radiologic measurements

Relationship between T1 slope and loss of lordosis after laminoplasty in patients with cervical ossification of the posterior longitudinal ligament

ObjectiveTo compare the superior‐level facet joint violations (FJV) between robot‐assisted (RA) percutaneous pedicle screw placement and conventional open fluoroscopic‐guided (FG) pedicle screw placement in a prospective cohort study.MethodsThis was a prospective cohort study without randomization. One‐hundred patients scheduled to undergo RA (n = 50) or FG (n = 50) transforaminal lumbar interbody fusion were included from February 2016 to May 2018. The grade of FJV, the distance between pedicle screws and the corresponding proximal facet joint, and intra‐pedicle accuracy of the top screw were evaluated based on postoperative CT scan. Patient demographics, perioperative outcomes, and radiation exposure were recorded and compared. Perioperative outcomes include surgical time, intraoperative blood loss, postoperative length of stay, conversion, and revision surgeries.ResultsOf the 100 screws in the RA group, 4 violated the proximal facet joint, while 26 of 100 in the FG group had FJV (P = 0.000). In the RA group, 3 and 1 screws were classified as grade 1 and 2, respectively. Of the 26 FJV screws in the FG group, 17 screws were scored as grade 1, 6 screws were grade 2, and 3 screws were grade 3. Significantly more severe FJV were noted in the FG group than in the RA group (P = 0.000). There was a statistically significant difference between RA and FG for overall violation grade (0.05 vs 0.38, P = 0.000). The average distance of pedicle screws from facet joints in the RA group (4.16 ± 2.60 mm) was larger than that in the FG group (1.92 ± 1.55 mm; P = 0.000). For intra‐pedicle accuracy, the rate of perfect screw position was greater in the RA group than in the FG group (85% vs 71%; P = 0.017). No statistically significant difference was found between the clinically acceptable screws between groups (P = 0.279). The radiation dose was higher in the FG group (30.3 ± 11.3 vs 65.3 ± 28.3 μSv; P = 0.000). The operative time in the RA group was significantly longer (184.7 ± 54.3 vs 117.8 ± 36.9 min; P = 0.000).ConclusionsCompared to the open FG technique, minimally invasive RA spine surgery was associated with fewer proximal facet joint violations, larger facet to screw distance, and higher intra‐pedicle accuracy.

Multi-segmental thoracolumbar fracture (MSF) generally refers to fractures occurring in two or more segments of the thoracolumbar spine. With the development of minimally invasive concept, there is little research on its application in the field of MSF. The purpose of this study is to compare two minimally invasive surgical techniques and determine which one is more suitable for treating patients with neurologically intact MSF. We retrospectively analyzed the clinical data of 49 MSF patients with intact nerves who were admitted from January 2017 to February 2019. Among them, 25 cases underwent percutaneous pedicle screw fixation (PPSF), and 24 cases underwent Wiltse approach pedicle screw fixation (WAPSF). The operation time, number of fixed segments, blood loss, length of incision, postoperative ambulation time, accuracy of pedicle screw placement, facet joint violation (FJV), number of C-arm exposures, as well as pre- and postoperative visual analogue scale (VAS), Oswestry disability index (ODI), local Cobb's angle (LCA), and percentage of anterior vertebral body height (PAVBH) were recorded for both groups. Paired sample t-test was used for intra-group comparison before and after surgery while independent sample t-test was used for inter-group comparison. The differences in the number of fixed segments, intraoperative bleeding, postoperative bed time, accuracy rate of pedicle screw placement, VAS, and ODI between the two groups were not statistically significant (p > 0.05). However, the operative time and total surgical incision length were significantly shorter in the WAPSF group than in the PPSF group (p < 0.05), and the FJV was significantly higher in the PPSF group than in the WAPSF group (p < 0.05). Also, the PPSF group received more intraoperative fluoroscopy (p < 0.05). The result of LCA and PAVBH in the WAPSF group were significantly better than in the PPSF group (p < 0.05). Both PPSF and WAPSF were found to be safe and effective in the treatment of MSF without neurological deficits through our study. However, considering radiation exposure, FJV, vertebral height restoration, correction of kyphosis, and learning curve, WAPSF may be a better choice for neurologically intact MSF.