Hybrid Decompression Research Articles

Anterior Cervical Hybrid Decompression and Fusion Surgery to Treat Multilevel Cervical Spondylotic Myelopathy.

Cervical spondylotic myelopathy (CSM) is a common disease resulting from intervertebral disc herniation, ossification of the posterior longitudinal ligament, and other pathological changes that cause spinal cord compression. CSM progresses insidiously with mild upper-limb numbness, which patients tend to ignore. As the condition worsens, the patients may experience a limp, limited fine motor activity, and eventually, a loss of daily activity. Conservative treatments, such as physical therapy and medication, are frequently ineffective for CSM. Once surgery is deemed to be required, decompression surgery is the best option. So far, both anterior cervical discectomy and fusion (ACDF) and anterior cervical corpectomy and fusion (ACCF) have been commonly used to treat CSM. In addition, a type of hybrid procedure that combines ACDF with ACCF has been used to treat some CSM cases and achieved satisfying results. Thus, this study aims to introduce this hybrid surgical technique and advocate for it based on its patient success.

Quantitatively biomechanical response analysis of posterior musculature reconstruction in cervical single-door laminoplasty

Background and objectiveThe current trend of laminoplasty is developing toward the goal of muscle preservation and minimum tissue damage. Given this, muscle-preserving techniques in cervical single-door laminoplasty have been modified with protecting the spinous processes at the sites of C2 and/or C7 muscle attachment and reconstruct the posterior musculature in recent years. To date, no study has reported the effect of preserving the posterior musculature during the reconstruction. The purpose of this study is to quantitatively evaluate the biomechanical effect of multiple modified single-door laminoplasty procedures for restoring stability and reducing response level on the cervical spine. MethodsDifferent cervical laminoplasty models were established for evaluating kinematics and response simulations based on a detailed finite element (FE) head-neck active model (HNAM), including ① C3 – C7 laminoplasty (LP_C37), ② C3 – C6 laminoplasty with C7 spinous process preservation (LP_C36), ③ C3 laminectomy hybrid decompression with C4 – C6 laminoplasty (LT_C3 + LP_C46) and ④ C3 – C7 laminoplasty with unilateral musculature preservation (LP_C37 + UMP). The laminoplasty model was validated by the global range of motion (ROM) and percentage changes relative to the intact state. The C2 – T1 ROM, axial muscle tensile force, and stress/strain levels of functional spinal units were compared among the different laminoplasty groups. The obtained effects were further analysed by comparison with a review of clinical data on cervical laminoplasty scenarios. ResultsAnalysis of the locations of concentration of muscle load showed that the C2 muscle attachment sustained more tensile loading than the C7 muscle attachment, primarily in flexion-extension (FE) and in lateral bending (LB) and axial rotation (AR), respectively. Simulated results further quantified that LP_C36 primarily produced 10% decreases in LB and AR modes relative to LP_C37. Compared with LP_C36, LT_C3 + LP_C46 resulted in approximately 30% decreases in FE motion; LP C37 + UMP also showed a similar trend. Additionally, when compared to LP_C37, LT_C3 + LP_C46 and LP C37 + UMP reduced the peak stress level at the intervertebral disc by at most 2-fold as well as the peak strain level of the facet joint capsule by 2–3-fold. All these findings were well correlated with the result of clinical studies comparing modified laminoplasty and classic laminoplasty. ConclusionsModified muscle-preserving laminoplasty is superior to classic laminoplasty due to the biomechanical effect of the posterior musculature reconstruction, with a retained postoperative ROM and loading response levels of the functional spinal units. More motion-sparing is beneficial for increasing cervical stability, which probably accelerates the recovery of postoperative neck movement and reduces the risk of the complication for eventual kyphosis and axial pain. Surgeons are encouraged to make every effort to preserve the attachment of the C2 whenever feasible in laminoplasty.

Treatment of three-level cervical spondylotic myelopathy using ACDF or a combination of ACDF and ACCF.

ObjectivesThis study aims to compare the outcomes between two anterior decompression and fusion techniques to treat multilevel cervical spondylotic myelopathy (MCSM).MethodsAfter the screening for eligibility, a total of 66 patients were admitted to this study. These participants underwent anterior surgeries due to MCSM in our hospital between June 2016 and July 2018. All participants underwent either the anterior cervical discectomy and fusion (ACDF) surgery (ACDF group) or the combination of ACDF and anterior cervical corpectomy and fusion (ACCF), which was the anterior cervical hybrid decompression and fusion (ACHDF) surgery group. All the patients were followed up ≥18 months, the average latest followed up time was 23.64 (±2.69) months. The length of hospitalization, operation time, blood loss, visual analog scale (VAS), Japanese Orthopaedic Association (JOA) score, improvement rate, Hounsfield units (HU) of C3–C7, cobb angle, and anterior column height of fusion levels pre and post operation were analyzed.ResultsThere were no statistical differences between the ACDF and ACHDF groups regarding the length of hospitalization, operation time, blood loss, HU of C3–C7, VAS, JOA score, improvement rate, cobb angle, and anterior column height in fusion levels in pre-operation and 3 months after operation (all P > 0.05). However, compared with the ACHDF group, the ACDF group achieved significantly better improvement in the anterior column height of fusion levels in the final 18–29 months post-operatively (P < 0.05).ConclusionsBoth approaches of ACDF alone and a combination of ACDF and ACCF can achieve satisfactory outcomes in the treatment of MCSM, but ACDF has better outcomes in maintaining anterior column height of fusion levels.

The Pre-Operative Duration of Symptoms: The Most Important Predictor of Post-Operative Efficacy in Patients with Degenerative Cervical Myelopathy.

Objective. To explore the most important predictors of post-operative efficacy in patients with degenerative cervical myelopathy (DCM). Methods. From January 2013 to January 2019, 284 patients with DCM were enrolled. They were categorized based on the different surgical methods used: single anterior cervical decompression and fusion (ACDF) (n = 80), double ACDF (n = 56), three ACDF (n = 13), anterior cervical corpectomy and fusion (ACCF) (n = 63), anterior cervical hybrid decompression and fusion (ACHDF) (n = 25), laminoplasty (n = 38) and laminectomy and fusion (n = 9). The follow-up time was 2 years. The patients were divided into two groups based on the mJOA recovery rate at the last follow-up: Group A (the excellent improvement group, mJOA recovery rate >50%, n = 213) and Group B (the poor improvement group, mJOA recovery rate ≤50%, n = 71). The evaluated data included age, gender, BMI, duration of symptoms (months), smoking, drinking, number of lesion segments, surgical methods, surgical time, blood loss, the Charlson Comorbidity Index (CCI), CCI classification, imaging parameters (CL, T1S, C2-7SVA, CL (F), T1S (F), C2-7SVA (F), CL (E), T1S (E), C2-7SVA (E), CL (ROM), T1S (ROM) and C2-7SVA (ROM)), maximum spinal cord compression (MSCC), maximum canal compromise (MCC), Transverse area (TA), Transverse area ratio (TAR), compression ratio (CR) and the Coefficient compression ratio (CCR). The visual analog score (VAS), neck disability index (NDI), modified Japanese Orthopedic Association (mJOA) and mJOA recovery rate were used to assess cervical spinal function and quality of life. Results. We found that there was no significant difference in the baseline data among the different surgical groups and that there were only significant differences in the number of lesion segments, C2–7SVA, T1S (F), T1S (ROM), TA, CR, surgical time and blood loss. Therefore, there was comparability of the post-operative recovery among the different surgical groups, and we found that there were significant differences in age, the duration of symptoms, CL and pre-mJOA between Group A and Group B. A binary logistic regression analysis showed that the duration of the symptoms was an independent risk factor for post-operative efficacy in patients with DCM. Meanwhile, when the duration of symptoms was ≥6.5 months, the prognosis of patients was more likely to be poor, and the probability of a poor prognosis increased by 0.196 times for each additional month of symptom duration (p < 0.001, OR = 1.196). Conclusion. For patients with DCM (regardless of the number of lesion segments and the proposed surgical methods), the duration of symptoms was an independent risk factor for the post-operative efficacy. When the duration of symptoms was ≥6.5 months, the prognosis of patients was more likely to be poor, and the probability of a poor prognosis increased by 0.196 times for each additional month of symptom duration (p < 0.001, OR = 1.196).

Increased Neck Tilt/T1 slope ratio may play an important role in patients with cervical kyphosis

BackgroundIn previous studies, we demonstrated that the T1 slope (T1s) is associated with clinical outcomes, but the results were not specific for individuals. A recent study suggested that an increased pelvic tilt (PT)/sacral slope (SS) ratio may play an important role in the degeneration of lumbar scoliosis and pathogenesis of lumbar spondylolisthesis. Therefore, we aimed to explore the role of neck tilt (NT)/T1s in patients with cervical kyphosis.MethodsIn total, the data of 36 kyphosis patients who underwent anterior cervical hybrid decompression and fusion (ACHDF) for multilevel (3 levels) cervical spondylotic myelopathy were retrospectively analyzed. The radiographic measurements included the T1s, NT, C2–7 Cobb angle, and C2–7 sagittal vertical axis (SVA). The visual analog scale (VAS) and neck disability index (NDI) scores were used to determine the clinical prognosis. Pearson’s correlation coefficient was calculated to assess the relationships among preoperative imaging examination parameters.ResultsThe mean C2–7 Cobb angle was − 5.93 ± 3.00° before surgery, 9.67 ± 6.61° after surgery, and 7.91 ± 8.73° at the follow-up. The preoperative NT/T1s ratio was positively correlated with the ΔC2–7 Cobb angle (r = 0.358, p < 0.05) and negatively correlated with the preoperative C2–7 Cobb angle (r = -0.515, p < 0.01) and preoperative C2–7 SVA (r = -0.461, p < 0.01). The linear regression model indicated a positive correlation between the preoperative NT/T1s ratio and the ΔC2–7 Cobb angle (R2 = 0.122).ConclusionsThe preoperative NT/T1s ratio may be positively correlated with changes in postoperative cervical spine curvature (Cobb angle). The NT/T1s ratio may be worthy of increased attention among sagittal parameters.

Association Between C5 Palsy and the Anterior Decompression Procedures, Corpectomy and Discectomy.

This is a retrospective study. The aim was to evaluate the influence of various decompression procedures on the incidence of C5 palsy (C5P). C5P is a well-known but unsolved complication of cervical spine surgery. Among anterior cervical decompressive procedures, both corpectomy and discectomy are important surgical methods, whose effects on the incidence of C5P are unknown. We retrospectively analyzed 818 patients (529 men; mean age: 59.2±11.6 y) who underwent anterior cervical decompression and fusion. The surgical choice to use corpectomy, discectomy, or hybrid decompression was based on standard treatment strategies depending on local compressive pathology and presenting clinical symptoms. We introduced an original "decompression combination score" as a means of quantifying the effects of the procedures on the development of C5P. The scores were based on the relative severity of various risk factors associated with the eventual development of C5P and were assigned as follows: C4 corpectomy, 1 point; C5 corpectomy, 1 point; C3 corpectomy successive to C4 corpectomy, 0.5 point; C6 or C7 corpectomy successive to C5 corpectomy, 0.5 point; C4/5 discectomy, 0.5 point; discectomy at another segment, 0 point. Each patient's decompression combination score was then comprised of the sum of these points. C5P occurred in 55 (47 men, mean age: 65.7±8.7 y) of the 818 (6.7%) patients. A larger number of operated disc segments was significantly associated with C5P. Higher decompression combination score was significantly associated with C5P. Multivariate analysis revealed that male sex, higher decompression combination score, and older age were significant risk factors. Corpectomy increased the incidence of C5P, while discectomy decreased the risk. The lower incidence of postoperative C5P after discectomy may be because of minimizing tethering effect to the C5 nerve root. As a preventive measure against C5P, corpectomy should be avoided, while discectomy is recommended as much as possible. Levels of Evidence: Step IV-Oxford Center for Evidence-Based Medicine 2011.

Anterior Controllable Antedisplacement and Fusion (ACAF) Technique for the Treatment of Multilevel Cervical Spondylotic Myelopathy With Spinal Stenosis (MCSMSS): A Retrospective Study of 54 Cases.

Retrospective study. To investigate the clinical effect of anterior controllable antedisplacement and fusion (ACAF) technique for the treatment of multilevel cervical spondylotic myelopathy with spinal stenosis (MCSMSS), compared with hybrid decompression fixation (HDF). A retrospective analysis of 94 cases with MCSMSS was carried out. Fifty-four patients were treated with ACAF, whereas 40 patients were treated with HDF. The operation time, intraoperative blood loss, postoperative complications, Japanese Orthopedic Association score, Neck Disability Index score, parameters at axial computed tomography, cervical curvature and the Kang grade were compared between 2 groups. The patients were followed up for 12-17 (15.6±1.6) months. Compared with HDF, ACAF group achieved better decompression according to computed tomography measurement and Kang grade (P<0.05), and recovered to a greater cervical Cobb angle (P<0.05). However, Japanese Orthopedic Association score and Neck Disability Index showed no significant difference 1 year after surgery (P>0.05). In addition, ACAF presented longer operation time (P<0.05) and similar intraoperative blood loss (P>0.05), compared with HDF. In terms of complications, ACAF produced less incidences of cerebrospinal fluid leakage, implant complication, epidural hematoma, and C5 palsy compared with HDF. ACAF is an effective method for the treatment of MCSMSS. In comparison to HDF, ACAF has the advantages of more sufficient decompression, more satisfactory cervical curvature, and lower incidence rates of complications.

A biomechanical analysis of four anterior cervical techniques to treating multilevel cervical spondylotic myelopathy: a finite element study

BackgroundThe decision to treat multilevel cervical spondylotic myelopathy (MCSM) remains controversial. The purpose of this study is to compare the biomechanical characteristics of the intervertebral discs at the adjacent segments and internal fixation, and to provide scientific experimental evidence for surgical treatment of MCSM.MethodsAn intact C2-C7 cervical spine model was developed and validated. Four additional models were developed from the fusion model, including multilevel anterior cervical discectomy and fusion (mACDF), anterior cervical corpectomy and fusion (ACCF), hybrid decompression and fusion (HDF), and mACDF with cage alone (mACDF-CA). Biomechanical characteristics on the plate and the disc of adjacent levels (C2/3, C6/7) were comparatively analyzed.ResultsOf the four models, stress on the upper (C2/3) adjacent intervertebral disc was the lowest in the mACDF-CA group and highest in the ACCF group. Stress on the intervertebral discs at adjacent segments was higher for the upper C2/3 than the lower C6/7 intervertebral disc. In all models, the mACDF-CA group had the lowest stress on the intervertebral disc, while the ACCF group had the highest stress. In the three surgical models with titanium plate fixation (mACDF, ACCF, and HDF), the ACCF group had the highest stress at the titanium plate-screw interface, while the mACDF group had the lowest stress.ConclusionAmong the four anterior cervical reconstructive techniques for MCSM, mACDF-CA makes little effect on the adjacent disc stress, which might reduce the incidence of adjacent segment degeneration (ASD) after fusion. However, the accompanying risk of the increased incidence of cage subsidence should never be neglected.

Hybrid decompression and reconstruction technique for cervical spondylotic myelopathy: case series and review of the literature

The primary treatment of choice for patients with cervical spondylotic myelopathy (CSM) is surgical decompression. The benefit of operative intervention has been well established but, the surgeons' decision of operative approach remains nuanced based on patient-specific variables and surgeon preference. Decompression can involve a cervical corpectomy or a discectomy. A hybrid construct is when both a cervical corpectomy and a discectomy are done in the same patient. The purpose of this study was to review the evidence on the clinical and biomechanical outcomes of hybrid decompression and reconstruction techniques in patients with multilevel CSM. A retrospective study was performed on consecutive patients who received hybrid anterior decompression and reconstruction at Rush University between 2013-2018. Preoperative clinical and radiographic variables were analyzed to characterize specific factors leading to the decision of the surgical approach. In addition, we performed a systematic review and meta-analysis to assess superiority in terms of operative time, blood loss, cervical lordosis, patient-reported outcomes (PRO), fusion rates, and complications. Hybrid surgery (HS) was utilized in cases where multilevel CSM was present in conjunction with stenosis posterior to the vertebral body or acute kyphotic deformity. Our meta-analysis highlighted comparable PRO, complications, and rate of success fusion between 3-level anterior cervical discectomy and fusion (ACDF) and hybrid technique. Furthermore, hybrid fusion led to increased postoperative cervical lordosis, higher fusion rate, lower total complication rate, lower implant failure/mesh subsidence rate, and lower blood loss than 2-level corpectomy. The cervical hybrid technique that combines cervical corpectomy and discectomy represents a balanced option with the benefits of two commonly utilized cervical spine procedures in patients with multilevel CSM. The literature on hybrid technique suggests in cases where multilevel ACDF is not feasible, combining discectomy and corpectomy is superior to two-level corpectomy with lower complication rates, improved clinical outcome, spinal alignment correction, and stronger biomechanical properties.

Low Power FPGA Implementation of Multi-View Video Coding with Hybrid Compression and Decompression Algorithm

The video is one of the most useful and most appealing medium to represent some information. More usage of digital multi-media via communications media, wireless communications, intranet, internet and cellular mobile leads to the uncontrollable growth of data in media. The video compression technique is used in this research work to improve the processing speed of the entire system. In this work, Low Cost - Multi Video Coding - Hybrid Compression and Decompression (LC-MVC-HCD) method is used to reduce computation complexity. The combinational of Discrete Wavelet Transform (DWT) and Discrete Cosine Transform (DCT) algorithms are denoted as hybrid algorithm. Based on this hybrid algorithm, the compression process is performing which improves the video coding efficiency of MVC. The LC-MVC-HCD methodwas implemented in the Matlab, Xilinx and Cadence tool. In Application Specific Integrated Circuit (ASIC) implementation, the area, power, and delay minimized by using the cadence encounter tool with 180nm and 45nm technology. In Field Programmable Gate Array (FPGA) implementation, the number of Lookup Tables (LUTs), slice, and flip-flop are minimized based on two different kinds of Virtex devices such as Virtex -6 and Virtex-7. In Matlab, Peak Signal to Noise Ratio (PSNR), computational time and bit error rate were analyzed for the LC-MVC-HCD method. The experimental outcome showed that the proposed methodology has improved performance ASIC and FPGA up to 2-3% compared to existing methods like Direct mode decision MVC and LC-MVC-DWT.

Biomechanical evaluation comparing zero-profile devices versus fixed profile systems in a cervical hybrid decompression model: a biomechanical in vitro study

BACKGROUND CONTEXTThe use of zero-profile devices and the need for posterior fixation in conjunction with a cervical hybrid decompression model have yet to be investigated. PURPOSETo compare the biomechanics of zero-profile and fixed profile cervical hybrid constructs composed of anterior cervical discectomy and fusion (ACDF) and anterior cervical corpectomy and fusion (ACCF). Fixed profile devices included anterior plating, whereas zero-profile devices included integrated screws. STUDY DESIGNIn vitro cadaveric biomechanical study. METHODSTwelve fresh-frozen cadaveric spines (C2–C7) were divided into two groups of equal bone mineral density, fixed profile versus zero profile (n=6). Groups were instrumented from C3–C6 with either (1) an expandable ACCF device and a static ACDF spacer with an anterior plate (Hybrid-AP) or (2) a zero-profile ACCF spacer with adjacent zero-profile ACDF spacer (Hybrid-Z). Motion was captured for the (1) intact condition, (2) a hybrid model with lateral mass screws (LMS), (3) a hybrid model without LMS, and (4) a hybrid model without LMS following simulated repetitive loading (fatigue). RESULTSHybrid-AP with LMS reduced motion in flexion-extension (FE), lateral bending (LB), and axial rotation (AR) by 77%, 88%, and 82%, respectively, compared with intact. Likewise, Hybrid-Z with LMS exhibited the greatest reduction in motion relative to intact in FE, LB, and AR by 90%, 95%, and 66%, respectively. Following simulated in vivo fatiguing, an increase in motion was observed for both groups in all planes, particularly during Hybrid-Z postfatigue condition where motion increased relative to intact by 29%. Overall, biomechanical equivalency was observed between Hybrid-AP and Hybrid-Z groups (p>.05). Three (50%) of the Hybrid-Z group specimens exhibited signs of implant migration from the inferior endplate during testing. CONCLUSIONSFixed profile systems using an anterior plate for supplemental fixation is biomechanically more favorable to maintain stability and prevent dislodgement. Dislodgement of 50% of the Hybrid-Z group without LMS emphasizes the necessity for posterior fixation in a zero-profile cervical hybrid decompression model.

Anterior Cervical Discectomy and Fusion Versus Hybrid Decompression and Fusion for the Treatment of 3-Level Cervical Spondylotic Myelopathy: A Comparative Analysis of Cervical Sagittal Balance and Outcomes

To compare the cervical sagittal balance and surgical outcomes between anterior cervical discectomy and fusion (ACDF) and hybrid decompression and fusion (HDF; 1-level corpectomy combined with 1-level discectomy) for consecutive 3-level cervical spondylotic myelopathy (CSM). From January 2013 to June 2016, 82 patients with 3-level CSM who underwent ACDF (n= 40) and HDF (n= 42) were retrospectively reviewed. Perioperative parameters, clinical outcomes, and radiologic sagittal alignment were analyzed and compared. Patients were followed up for 35.5 ± 6.5 months (range, 25-53 months). All patients had achieved significant improvement in Neck Disability Index and Japanese Orthopedic Association scores after operation, with similar clinical outcomes between both groups (P > 0.05). In the ACDF group, 2 patients were found with axial symptoms, and 1 with hoarseness. In the HDF group, 5 patients were found with axial symptoms, 1 with hoarseness, 1 with dysphagia, and 1 with pseudarthrosis. The ACDF group had less operation time and bleeding compared with the HDF group (P < 0.05). The restoration of segmental and C2-7 lordosis were significantly greater in the ACDF group than the HDF group (P < 0.05). The C2-7 sagittal vertical axis and T1 slope minus C2-7 lordosis decreased in the ACDF group at final follow-up (P < 0.05); however, there was no obvious change in those of the HDF group (P > 0.05). Both ACDF and HDF were safe and effective for the treatment of 3-level CSM. ACDF showed superiority to HDF in terms of less blood loss, shorter operation time, and better postoperative sagittal balance.

Comparison of Three Anterior Techniques in the Surgical Treatment of Three-Level Cervical Spondylotic Myelopathy with Intramedullary T2-Weighted Increased Signal Intensity

To compare the clinical and radiologic outcomes of 3 anterior surgical techniques for the treatment of 3-level cervical spondylotic myelopathy (CSM) and the evolution of intramedullary T2-weighted increased signal intensity (ISI). A total of 98 consecutive patients (61 males, 37 females) with 3-level CSM who underwent anterior cervical surgery between January 2006 and January 2016 were retrospectively enrolled. Based on different anterior reconstructive techniques, the patients were divided into 3 groups: anterior cervical discectomy and fusion (ACDF), anterior cervical corpectomy and fusion (ACCF), and hybrid decompression and fusion (HDF) groups. The Japanese Orthopaedic Association score and its recovery rate were used to evaluate the clinical outcomes. The cervical alignment and range of motion were used to assess radiologic outcomes. In addition, the signal change ratio and length of ISI were used to measure the ISI. No statistical differences in preoperative factors were found among the 3 groups (P > 0.05). Although the HDF group had intermediate surgery time and blood loss compared with other groups (P < 0.05), it achieved greater postoperative Japanese Orthopaedic Association score and recovery rate than other groups (P < 0.05). The postoperative C2-C7 lordotic angle and postoperative range of motion in the HDF group were similar to that in the ACDF group (P > 0.05), both greater than that in the ACCF group (P < 0.05). The incidence of complications in the HDF group was close to the ACDF group (P > 0.05), and both groups were lower than that in the ACCF group (P < 0.05). In addition, the postoperative signal change ratio in the HDF group was lower than in other groups (P < 0.05). The postoperative length of ISI in the HDF group was similar to the ACCF group (P > 0.05), which was both shorter than that in the ACDF group (P < 0.05). For patients with 3-level CSM with ISI on T2-weighted MRI, HDF can be considered as the optimal technique that achieves better clinical and radiologic outcomes than the ACDF or ACCF procedure. HDF also has a better postoperative regression of ISI compared with the ACDF or ACCF procedure, which may potentially be an important indicator for improving surgical outcomes.

Analysis of sagittal alignment parameters following anterior cervical hybrid decompression and fusion of multilevel cervical Spondylotic myelopathy

BackgroundTo investigate the relationships between sagittal parameters and health-related quality of life (HRQOL) scores following anterior cervical hybrid decompression and fusion (ACHDF) of multilevel cervical spondylotic myelopathy (CSM) and to study the impact of the T1 slope (T1 s).MethodsIn total, 42 patients with complete radiographic measurements following ACHDF in the Spine Surgery Department of the First Affiliated Hospital of Fujian Medical University from August 2014 to January 2017 were retrospectively analysed. Radiographic measurements included C2–7 lordosis, T1 s, C2–7 sagittal vertical axis (SVA), cervical tilting and cranial tilting. The neck disability index (NDI) was used to evaluate the HRQOL. Spearman’s correlation coefficients were calculated between pairs of cervical sagittal parameters and NDI scores.ResultsPreoperative NDI scores were correlated with preoperative T1 s (r = 0.413); follow-up NDI scores were correlated with follow-up T1 s (r = 0.534). The regression analysis indicated that a preoperative T1 s value of 42.36° corresponded to a preoperative NDI score of 25 (r2 = 0.171, P < 0.001). A follow-up T1 s value of 48.61° corresponded to a follow-up NDI score of 25 (r2 = 0.421, P < 0.01). The differences in C2–7 SVA and cranial tilting before and after the operation were statistically significant (P < 0.05).ConclusionThis study showed that the sagittal balance of the cervical vertebrae changed significantly after ACHDF, showing a forward trend. The sagittal parameters after ACHDF were related to clinical prognosis. An excessive T1 s can be considered a risk factor. The T1 s could provide a reference value to determine the correction of the sagittal balance of the cervical spine.

Placement of Titanium Mesh in Hybrid Decompression Surgery to Avoid Graft Subsidence in Treatment of Three-Level Cervical Spondylotic Myelopathy: Cephalad or Caudal?

BackgroundHybrid decompression has been used to treat patients with cervical spondylotic myelopathy (CSM). However, no published study has investigated the effect of titanium mesh (TM) located cephalad or caudal in hybrid decompression surgery on the graft subsidence in treatment of three-level CSM.Material/MethodsForty-eight cases with three-level CSM who underwent the procedure of hybrid decompression from Jan 2014 to Jan 2017 were retrospectively reviewed. Radiological outcomes immediately postoperatively and at the final follow-up were compared between cases from group A (TM located cephalad, n=21) and group B (TM located caudal, n=27).ResultsNo differences were observed in the 2 groups in terms of number, sex, or duration of follow-up. The average follow-up was 4.38±0.439 months in group A and 4.81±0.509 months in group B (p>0.05). The index loss of anterior (AIBH), middle (MIBH), and posterior interbody height (PIBH) in group A were 0.857±0.448/1.00±0.525/1.33±0.608, respectively, which were all lower than that in group B (P<0.05), as was the occurrence of TM subsidence. However, there was no significance difference in height loss of adjacent intervertebral space between groups. All angles were decreased at the final follow-up in both groups (p<0.05). More decrease of C2–C7 angle occurred in group B (p>0.05), and segmental angle in group A decreased more than in group B (p>0.05).ConclusionsTM inferior to intervertebral cage (IC) in hybrid decompression has a higher risk for developing subsidence, and when the choice of the position of TM is available in hybrid decompression surgery, TM located cephalad was recommend to alleviate TM subsidence.

Comparative analysis of two hybrid technique in treating multilevel cervical spondylotic myelopathy via anterior approach

To compare the clinical effects and complications of two hybrid decompression techniques in treating multilevel (>=3) cervical spondylotic myelopathy(MCSM). The clinical data of 124 patients with multilevel (>=3) cervical spondylotic myelopathy treated by surgery and follow-up from January 2008 to December 2016 were retrospectively analyzed. According to the different operative methods, the patients were divided into group A and group B. Anterior cervical discectomy and fusion (ACDF) combined with anterior cervical corpectomy and fusion with preserved posterior vertebral wall (PWCF) were performed in group A; ACDF combined with anterior cervical corpectomy and fusion(ACCF) were performed in group B. There were 44 males and 16 females in group A with an average age of (60.43±7.52) years old, 46 males and 18 females in group B with an average age of (61.61±6.39) years old. No significant differences were found in gender, age between two groups. The operative time, intraoperative blood loss, hospital stay, rate of complications, postoperative Japanese Orthopaedic Association (JOA) score and improvement of cervical curvature were compared between two groups. All the operations were successful. The follow-up time was 13 to 28(23.0±12.1) months in group A and 12 to 30(24.0±11.5) months in group B. The operative time, intraoperative blood loss, hospital stay in group B were higher than those in group A(P<0.05). A total of 37 patients occurred complications, including 14 cases in group A and 23 cases in group B. The incidence of complications was 23.33%(14/60) in group A and 35.94%(23/64) in group B. The incidence of complications in group B was significantly higher than that in group A(P<0.05). Postoperative JOA scores were significantly improved (P<0.01), there was no significant difference between two groups (P>0.05). The physiological curvature of cervical vertebra was improved significantly after operation, and there was no significant difference between two groups(P>0.05). Both surgical methods can obtain satisfactory clinical efficacy for multilevel(>=3) cervical spondylotic myelopathy, but compare with group B (ACDF combined with ACCF), group A (ACDF combined with PWCF) has shorter operation time, less trauma, less bleeding, and lower incidence of complications. ACDF combined with PWCF can be preferentially selected for the patients who corresponding to the indications.

Wednesday, September 26, 2018 7:35 AM–9:00 AM ePosters: P99. Laminoplasty and laminectomy hybrid decompression for the treatment of cervical spondylotic myelopathy with hypertrophic ligamentum flavum: a retrospective study

BACKGROUND CONTEXT Laminoplasty is widely used in patients with cervical spondylotic myelopathy (CSM); however, for CSM patients with hypertrophic ligamentum flavum (HLF), traditional laminoplasty does not include resection of a pathological ligamentum flavum. PURPOSE To report the outcomes of a posterior hybrid decompression protocol for the treatment of CSM)associated withHLF. STUDY DESIGN/SETTING This study retrospectively reviewed 116 CSM patients with HLF who underwent hybrid decompression with a minimum of 12 months of follow-up. The procedure consisted of reconstruction of the C4 and C6 laminae using CENTERPIECE plates with spinous process autografts, and resection of the C3, C5, and C7 laminae. Surgical outcomes were assessed using Japanese Orthopedic Association (JOA) score, recovery rate, cervical lordotic angle, cervical range of motion, spinal canal sagittal diameter, bone healing rates on both the hinge and open sides, dural sac expansion at the level of maximum compression, drift-back distance of the spinal cord, and postoperative neck pain assessed by visual analog scale. PATIENT SAMPLE During a consecutive 3-year period from February 2009 through April 2012, 283 patients underwent hybrid posteriordecompression in our hospital. The current study retrospectively reviewed 116 CSM patients with HLF who underwent thisprocedure. The researchers selected patients with CSM caused only by HLF (dorsal compression of the spinal cord owing to HLF) and patients with CSM caused by the combination of anterior disease plus HLF (dorsal compression of the spinal cord owing to HLF and anterior disease such as ossification of the posterior longitudinal ligament [OPLL], degenerative disk disease [DDD], and congenital pathologies). The inclusion criteria were: (1) a clear diagnosis made by history, physical examination, plain radiographs, computed tomography (CT), and magnetic resonance imaging (MRI); (2) complete pre- and postoperative imaging and clinical data records; (3) a minimum of 12 months’ postoperative follow-up. Exclusion criteria were: (1) CSM patients with multilevel anterior compression only; e.g., consecutive OPLL or DDD, bu without HLF; and (2) patients lost to follow-up. Of the 116 patients (89 men, 27 women [mean age 61.9 years], 55 also had segmental or localized OPLL, 41 also had cervical degenerative disk herniation (DDH), 11 also had developmental spinal canal stenosis (DSCS), and 9 had ossification of ligament flavum (OLF). Thirteen of 116 patients had single-level spinal canal stenosis, 29 had twolevel stenosis, 48 had three-level stenosis, and the remaining 26 patients had four- or five-level stenosis. OUTCOME MEASURES Results were analyzed using PASW Statistics for Windows, Version 18.0 (SPSS Inc., Chicago, IL, USA). Descriptive statisticswere used for demographics, and Student's t-test was used for continuous variables. Significance was set at P METHODS Not applicable. RESULTS No hardware failure or restenosis was noted. Postoperative JOA score improved significantly, with a mean recovery rate of 65.3±15.5%. Mean cervical lordotic angle had decreased 4.9° by 1 year after surgery (P CONCLUSIONS Hybrid laminectomy and autograft laminoplasty decompression using Centerpiece plates may facilitate bone healing and produce a comparatively satisfactory prognosis for CSM patients with HLF.

Anterior corpectomy combined with intervertebral decompression and fusion for multilevel cervical spondylotic myelopathy

To investigate the clinical outcomes of anterior corpectomy combined with anterior intervertebral decompression and fusion for multilevel cervical spondylotic myelopathy. The clinical data of 28 patients with multilevel cervical spondylotic myelopathy who underwent surgery from October 2012 to June 2014 were retrospectively analyzed. There were 18 males and 10 females, aged from 45 to 77 years old with an average of (60.11±9.37) years. Three levels were involved in 27 cases, while four levels were involved in 1 case. The preoperative JOA score was 8.89±1.87; the fusion segments angles was (4.87±4.56)°; and the cervical curvature was (11.68±1.25)°. Anterior hybrid decompression and fusion were performed in 28 patients. The fusion segments angles and the cervical curvature were assessed by X-rays at 1, 12 months after operation, respectively. JOA score was used to evaluate the clinical effect. The operative time was 163 min on average (ranged from 120 to 205 min), and intraoperative bleeding was 198 ml on average(ranged from 100 to 300 ml). Hoarseness occurred in 1 case and got recovery at 3 weeks after operation and choke cough occurred in 1 case, and got improvement at 1 week after operation. All the patients were regularly followed for 12-24 months with an average of(18.46±3.20) months. Graft bone obtained fusion at 12 months after operation and the position of internal fixation was good. The fusion segments angles, the cervical curvature and JOA scores were significantly improved at 1, 12 months after operation(P<0.05). The improvement rate of JOA score was(46.46±20.26)% at 12 months after operation, 12 cases got excellent results, 14 good and 2 fair. Anterior corpectomy combined with anterior intervertebral decompression and fusion is safe and effective and can get satisfactory effects for multilevel cervical spondylotic myelopathy.

Hybrid Decompression and Fixation Technique Versus Plated 3-Vertebra Corpectomy for 4-Segment Cervical Myelopathy

A retrospective comparative study. The purpose of this study was to compare the stability and outcomes of a hybrid technique with those of a 3-vertebra corpectomy in the management of 4-segment cervical myelopathy. Patients with primarily ventral disease and loss of cervical lordosis are considered good candidates for anterior surgery. Cervical corpectomy is commonly performed in patients with multilevel cervical myelopathy. Corpectomies including >3 vertebraes entail an extremely high risk of reconstruction failure. To avoid the need to perform a 3-vertebra corpectomy, we use a hybrid decompression and fixation technique. This hybrid technique is a technique to obtain optimum decompression and fixation in patients with multilevel cervical myelopathy. A total of 81 patients with multilevel cervical myelopathy who underwent 4-segment cervical fixation with a minimum 2-year follow-up were included. The hybrid technique involved combining a plated 2-vertebra corpectomy and single-level discectomy with stand-alone cage fixation. This technique was performed in 39 patients, and the plated 3-vertebra corpectomy was performed in 42 patients. Nine patients (21%) who underwent the plated 3-vertebra corpectomy were treated with halo immobilization, but no patient in the hybrid group required this treatment (P=0.002). There were fewer instances of reconstruction failure in the hybrid group than in the 3-vertebra corpectomy group (0% vs. 10%, respectively; P=0.048) and fewer instances of C5 palsy (3% vs. 17%, respectively; P <0.0001). The incidence of postoperative C5 palsy was 25% for C3-C5 corpectomy, 19% for C4-C6 corpectomy, and 11% for C4-C5 corpectomy+C6-C7 discectomy. The hybrid technique has the following advantages over 3-vertebra corpectomy for 4-segment cervical fixation: a shorter graft bone and plate are required; the fixed segment has greater initial stability; postoperative external immobilization is simplified; and the risk of reconstruction failure and postoperative C5 palsy is reduced markedly.

Hybrid Decompression and Fixation Technique for the Treatment of Multisegmental Cervical Spondylotic Myelopathy.

Cervical spondilotic myelopathy (CSM) is defined as the compromise of the spinal cord due to degenerative changes of the cervical spine. It is the most common cause of spinal cord dysfunction in patients over 55 years. An early surgical management it is paramount to achieve better neurological outcome. There is still controversy regarding the appropriate surgical treatment for multisegmental CSM involving three or more levels. The hybrid decompression and fixation technique combines one or two level corpectomy and a single level discectomy in order to obtain optimum decompression and fixation in patients with multilevel cervical myelopathy. A prospective case-control study was made between 2011 and 2013. A total of 15 patients with diagnosis of CSM received surgical treatment with an anterior hybrid decompression and fixation technique procedure. Inclusion criteria were myelopathy confirmed by radiographic studies, magnetic resonance image (MRI) and electromyography. During the 2010-2013 period 15 patients were managed by hybrid decompression and fixation technique. Average age 64.8 years SD9.4. The follow up period was 29.6 SD ± 9.8 months. The JOA score improved significantly to 13.8 +/- 1.9 points at follow-up (paired t test, P = 0.001), Nurick Scale preoperative was 3.3 and improved to 2.4 mean, was significantly (Wilcoxon signed rank test p=0.006) The mean C2-C7 lordosis angle was 10.8° +/- 8.9 before surgery, and 14.3° +/- 8.8 at follow-up, there was no significant loss of lordosis angle between the preoperative and follow-up measurements (Wilcoxon signed rank test, P =0.149); At follow-up, graft non fusion was seen in 1 patient (7%, k=1). In this small number, single surgeon, prospective series the use of a single level corpectomy and an adjacent discectomy was shown to provide similar outcomes and complication rates as alternative surgical techniques. The authors thus consider this a viable surgical alternative with some perceived advantages, a low rate of complications and a high rate of spinal fusion. Level of Evidence: IV. This study was approved by the authors' Institutional Review Board and all patients were given informed consent prior to participation in the study.