Final Japanese Orthopaedic Association Research Articles

Comparison of Surgical Outcomes After Posterior Decompression by Junior or Senior Surgeons for Patients With Cervical Ossification of the Posterior Longitudinal Ligament: Results From Retrospective Multicenter Cohort Study.

Retrospective multicenter study. To investigate surgical outcomes following posterior decompression for cervical ossification of the posterior longitudinal ligament (OPLL) when performed by board-certified spine (BCS) or non-BCS (NBCS) surgeons. We included 203 patients with cervical OPLL who were followed for a minimum of 1year after surgery. Demographic information, medical history, and imaging findings were collected. Clinical outcomes were assessed preoperatively and at the final follow-up using the Japanese Orthopedic Association (JOA) score and the visual analog scale (VAS) for the neck. We compared outcomes between BCS surgeons, who must meet several requirements, including experience in more than 300 spinal surgeries, and NBCS surgeons. BCS surgeons performed 124 out of 203 cases, while NBCS surgeons were primary in 79 cases, with 73.4% were directly supervised by a BCS surgeon. There was no statistically significant difference in surgical duration, estimated blood loss, and perioperative complication rates between the BCS and NBCS groups. Moreover, no statistically significant group differences were observed in each position of the C2-7 angle and cervical range of motion at preoperation and the final follow-up. Preoperative and final follow-up JOA scores, VAS for the neck, and JOA score recovery rate were comparable between the two groups. Surgical outcomes, including functional recovery, complication rates, and cervical dynamics, were comparable between the BCS and NBCS groups. Consequently, posterior decompression for cervical OPLL is considered safe and effective when conducted by junior surgeons who have undergone training and supervision by experienced spine surgeons.

Sagittal sequence and clinical efficacy of cervical disc replacement and hybrid surgery in the treatment of cervical spondylotic myelopathy: a retrospective study.

Hybrid surgery (HS) combines anterior cervical discectomy and fusion (ACDF) with cervical disc replacement (CDR) is gradually being more frequently implemented, but there are few studies reporting the safety and effectiveness of hybrid surgery in three levels cervical spondylotic myelopathy. The clinical and radiographic data of patients with three-segment cervical spondylosis, who underwent CDR, ACDF and HS in our hospital from February 2007 to February 2013 were analyzed. The Visual Analog Scale (VAS), Japanese Orthopedic Association (JOA) and Neck Disability Index (NDI) were used to evaluate the clinical efficacy post surgery. Cervical spine x-rays were conducted to assess ROM, CL, T1S and relevant outcomes. A total of 94 patients were included in the study: 26 in the CDR group, 13 in the HS1 group, 31 in the HS2 group, and 24 in the ACDF group. Most patients in the CDR group were younger. There was no difference in the follow-up duration, blood loss volume or surgery time (P > 0.05). Four groups reported improvements in JOA and NDI scores compared to baseline. There was no significant difference in the final JOA, final NDI or recovery rate among the 4 groups. The final ROM was smaller in the ACDF group than in the other 3 groups. There was no difference among the four groups in the final UROM, final LROM or their changes. There was no difference in the final T1S, final SVA or their change among the four groups. All groups showed similar changes in CL and T1S-CL. There was no difference in the clinical outcomes of ACDF, CDR, or hybrid surgery. CDR can better preserve the mobility of the cervical spine. Neither CDR nor hybrid surgery was significantly advantageous over ACDF in restoring the sagittal sequence in patients with three-level CSM.

Nano-hydroxyapatite/Polyamide 66 cage in anterior cervical corpectomy and fusion: a comprehensive systematic review and meta-analysis.

This study aimed to conduct a meta-analysis to compare the effectiveness and safety between titanium mesh cage (TMC) and nano-hydroxyapatite/polyamide 66 cage (n-HA/PA66) in the surgical treatment of cervical spondylotic myelopathy (CSM) through anterior cervical corpectomy and fusion (ACCF). We implemented a comprehensive search strategy across multiple databases, including Wanfang, China Knowledge Network, China Biomedical Literature Database, Wipu, PubMed, Cochran, Embase, and Web of Science. To ensure a thorough examination of available literature, the databases were searched from their inception to January 2023. Two independent researchers evaluated the quality of the included studies by using established criteria. We used RevMan 5.4 (Review Manager Web, The Cochrane Collaboration, Copenhagen, Denmark) to facilitate data extraction and analysis. This analysis included seven controlled clinical studies. The meta-analysis results showed no statistically significant differences between the two groups in terms of operating time, intraoperative bleeding, preoperative Japanese Orthopedic Association (JOA) score, preoperative visual analog scale (VAS) score, preoperative and final follow-up C2-7 Cobb angles, and intervertebral fusion rate (p > 0.05). However, a significant difference was observed between the two groups in terms of the final follow-up JOA [MD = 0.77, 95% CI (0.58, 0.97), p < 0.00001], VAS [MD = -0.50, 95% CI (-0.71, -0.30), p < 0.00001], and sedimentation rate [RR = 0.30, 95% CI (0.18, 0.48), p < 0.00001]. The use of n-HA/PA66 in ACCF for treating CSM is safe and effective treatment with positive clinical efficacy. In addition, n-HA/PA66 has both effective clinical efficacy and significantly lower fusion settling rates compared to TMC.

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

Retrospective. To investigate the efficacy of cervical single open-door laminoplasty with and without local lateral mass screw fixation and fusion as treatments for cervical spinal cord injuries accompanied by multisegmental spinal canal stenosis. The Second Affiliated Hospital, School of Medicine, Zhejiang University. Of all enrolled patients, 42 formed a stable group who underwent cervical single open-door laminoplasty alone and 14 formed an unstable group who underwent the procedure combined with lateral mass screw fixation and fusion. Neurological function was evaluated before surgery, at discharge, and at final follow-up using the American Spinal Cord Injury Association (ASIA) impairment scale and the Japanese Orthopedic Association (JOA) score. ASIA scores reflected improved neurological function in 52.5% of the stable group (15 with grade-D and 4 with grade-A injuries did not improve) and 45.5% of the unstable group (3 with grade-D and 3 with grade-A injuries did not improve). Postoperative JOA scores reflected 19.1% ± 21.6% improvement in the stable group and 18.6% ± 18.4% improvement in the unstable group (P > 0.05). Final follow-up JOA scores reflected 49.2% ± 31.7% improvement in the stable group and 47.1% ± 39.2% improvement in the unstable group (P > 0.05). Laminoplasty combined with local fusion aided the treatment of unstable cervical spinal cord injuries and spinal stenosis. Such stenosis is the main pathological factor causing multiple spinal cord compressions in patients with cervical spinal cord injuries.

Changes in T1 slope and cervical sagittal vertical axis correlate to improved neurological function recovery after cervical laminoplasty.

PurposeTo investigate the influence of changes in T1 slope (T1S) and cervical sagittal vertical axis (CSVA) on cervical laminoplasty outcomes.MethodsEighty-one patients with cervical spondylotic myelopathy (CSM) treated with cervical laminoplasty were enrolled in this study. Demographic parameters included age and follow-up time. Imaging data included occiput-C2 lordosis (OC2), C2–C7 Cobb angle (CL), T1S, CSVA. Outcome assessment indicators included the Japanese Orthopedic Association (JOA) score, JOA recovery rate, and neck disability index (NDI). All patients were grouped based on preoperative T1S and variation in CL after surgery, respectively. Patients with decreased CL postoperatively were further grouped according to whether they were combined with T1S reduction.ResultsThere were no significant differences in the final JOA score, JOA recovery rate, or NDI between patients with different T1S. Patients with loss of CL postoperatively had lower JOA score and JOA recovery rate, but higher NDI than patients with sustained CL. Furthermore, patients with CL loss but compensate for it with reduction in T1S had lower CSVA, higher JOA score and JOA recovery rate than those with CL loss alone.ConclusionsDecreased T1S postoperatively prevents the tendency of the cervical spine to tilt forward by regulating CSVA and facilitates recovery of neurological function after cervical laminoplasty.

Comparison of hidden blood loss and clinical efficacy of percutaneous endoscopic transforaminal lumbar interbody fusion and minimally invasive transforaminal lumbar interbody fusion

PurposeHidden blood loss (HBL) is a growing area of interest for spinal surgeons. Simultaneously, spine surgeons’ pursuit of minimally invasive spine surgery has never ceased, as evidenced by the increasing number of articles comparing percutaneous endoscopic transforaminal lumbar interbody fusion (Endo-TLIF) and minimally invasive transforaminal lumbar interbody fusion (Mis-TLIF). However, there has been no comparison of HBL between Endo-TLIF and Mis-TLIF. This study aimed to compare HBL, visible blood loss (VBL), and total blood loss (TBL) following Endo-TLIF and Mis-TLIF and evaluate the clinical significance of these procedures.MethodsBetween October 2017 and October 2019, 370 patients underwent lumbar interbody fusion at our institution and were followed up for at least 24 months. Our study included 41 Endo-TLIF and 43 Mis-TLIF cases. We recorded each patient’s age, height, weight, and haematocrit and calculated the TBL, which was used to indirectly obtain the HBL. Additionally, we compared the clinical outcomes of these two groups, including visual analogue scores for the lumbar spine and leg (VAS-Back; VAS-Leg), Oswestry Disability Index (ODI), Japanese Orthopaedic Association (JOA) scores, disease type, operative segment, and intervertebral fusion and complication rates.ResultsEndo-TLIF had significantly lower HBL, VBL, and TBL values than Mis-TLIF (P < 0.05 for all). Although Endo-TLIF contained significantly less HBL than Mis-TLIF, the HBL to TBL ratio was statistically greater in Endo-TLIF (91%) than in Mis-TLIF (87%). Concerning clinical outcomes, VAS-Back, VAS-Leg, ODI, JOA, and Endo-TLIF demonstrated greater improvement rates than Mis-TLIF one week post-operatively. However, at the final follow-up, VAS-Back, VAS-Leg, ODI, and JOA scores all demonstrated a trend toward sustained improvement, with no statistically significant between-procedure difference. There were no statistically significant between-procedure differences in disease type, surgical segment, and complication or fusion rates.ConclusionEndo-TLIF significantly reduced HBL, VBL, and TBL compared to Mis-TLIF and improved short-term clinical outcomes; however, long-term clinical outcomes and fusion rates remained comparable between the two groups, as did the incidence of peri-operative complications.

Instrumented fusion versus instrumented non-fusion following expansive open-door laminoplasty for multilevel cervical ossification of the posterior longitudinal ligament.

To compare the outcomes of expansive open-door laminoplasty with instrumented fusion (ELIF) and expansive open-door laminoplasty with instrumented non-fusion (ELINF) for multilevel cervical ossification of the posterior longitudinal ligament (OPLL). Patients who underwent ELIF or ELINF due to multilevel cervical OPLL from June 2013 to June 2019 were identified. Clinical and radiological outcomes were compared between the two groups. A total of 78 patients were enrolled in this study with a minimum follow-up of 24months, including 42 patients in the ELIF group and 36 patients in the ELINF group. At the final follow-up, sagittal vertical axis (SVA) and C2-C7 Cobb angle in the ELIF group were significantly better than those in the ELINF group, and cervical range of movement (ROM) in the ELIF group decreased significantly than that in the ELINF group. The incidence of OPLL progression at the final follow-up was 4.76% (2/42) in the ELIF group and 27.78% (10/36) in the ELINF group. Postoperative Japanese Orthopaedic Association (JOA) score, neck disability index (NDI), and visual analog scale (VAS) score improved significantly in each group, but JOA score and recovery rate (RR) in the ELIF group were significantly better than those in the ELINF group at the final follow-up. When K-line was positive, the difference in the final JOA score between the two groups was not significant, but the RR in the ELIF group was significantly better than that in the ELINF group. When K-line was negative, the final JOA score and RR in the ELIF group were significant higher than those in the ELINF group. ELIF and ELINF were two effective surgical procedures for treating multilevel cervical OPLL. However, ELIF was superior to ELINF due to better postoperative JOA score and RR, significant improvement of C2-C7 Cobb angle and maintenance of SVA, and suppressant effect on OPLL progression, especially for patients with K-line (-) OPLL.

Comparative Clinical and Radiographic Cohort Study: Uniportal Thoracic Endoscopic Laminotomy With Bilateral Decompression by Using the 1-Block Resection Technique and Thoracic Open Laminotomy With Bilateral Decompression for Thoracic Ossified Ligamentum Flavum.

Symptomatic thoracic myelopathy secondary to thoracic ossified ligamentum flavum (OLF) often requires decompression spinal surgery. To compare clinical and radiological outcomes in uniportal endoscopic vs open thoracic decompression for thoracic OLF. Retrospective evaluation of patients who underwent uniportal thoracic endoscopic unilateral laminotomy with bilateral decompression (TE-ULBD) by using the one-block resection technique compared with thoracic open laminotomy (TOL) with bilateral decompression. Radiological outcomes in MRI scan and clinical charts were evaluated. Thirty-five levels of TE-ULBD were compared with 24 levels of TOL. The overall complication rate of TOL was 15% while TE-ULBD was 6.5%. Both TOL and TE-ULBD cohort had significantly improved their visual analog scale (VAS), Oswestry Disability Index, and Japanese Orthopaedic Association (JOA) myelopathy score after operation. Comparative analysis of TE-ULBD performed statistically and significantly better than TOL in improvement of final VAS and JOA scores. The mean difference ± standard deviation of VAS and JOA improvement in final follow-up when compared with preoperative state of TE-ULBD and TOL was 0.717 ± 0.131 and 1.03 ± 0.2, respectively, P < .05. The mean Hirabayashi recovery rates were 94.5% (TE-ULBD) and 56.8% (TOL). There was no statistical difference in change in preoperative and final Oswestry Disability Index and MRI volume at upper endplate, middisk, and lower endplate canal cross-sectional area. Uniportal TE-ULBD achieved significantly improved pain and neurological recovery with sufficient spinal canal decompression, as compared with thoracic open laminectomy for patients with myelopathy secondary to OLF in our cohort.

Impact of timing of surgery on traumatic central cord syndrome without fracture or dislocation

ObjectiveThe management of acute traumatic central cord syndrome (ATCCS) remains controversial. The purpose of this study was to evaluate the impact of timing of surgery on patients with ATCCS without fracture or dislocation. MethodsForty-one patients with ATCCS without fracture or dislocation were identified and divided into three groups described as the conservative treatment group, early surgery group, and delayed surgery group. Clinical outcomes including ASIA Motor Score (AMS), Japanese Orthopaedic Association (JOA) score upon admission and follow-up, change in AMS, and JOA recovery rate were analyzed. Logistic regression analysis was performed to show the correlation between timing of surgery and clinical outcomes. ResultsAll patients received a minimum of 1-year follow-up and showed significant neurological recovery at the final follow-up. No statistical differences in final AMS and JOA scores were observed between the three groups. Patients who underwent early surgery achieved a faster motor recovery at the first 6-months postoperatively compared to conservative treatment(p < 0.01). There was a significant negative correlation between the timing of surgery and the change in AMS (r = -0.41, p = 0.02) in the initial 6-months postoperatively and throughout the follow-up period (r = -0.42, p = 0.02). ConclusionsThe present study indicated that both conservative and surgical treatments can lead to good neurological recovery in patients with ATCCS without fracture or dislocation. Early surgery allowed for rapid early motor recovery compared to conservative treatment. The choice of timing of surgery still requires individualized decision-making.

The Kappa Line as a Regional Modification of the K-line: A Predictor of Neurological Outcome and Indicator of the Adequate Level of Decompression in Selective Laminoplasty.

This is a retrospective cohort study. The aim was to introduce Kappa line (modification of K-line) for the prediction of postoperative neurological recovery after selective cervical laminoplasty (LMP) and use in determining the decompression level. The K-line is a radiographic marker that can predict prognosis and aid in surgical planning for patients undergoing LMP through C3 to C7. However, its efficacy in LMP involving limited segments is unclear. Furthermore, no specific radiographic marker to predict the prognosis of selective LMP has been reported. Fifty-one consecutive patients with a minimum 2-year follow-up after selective LMP for cervical myelopathy caused by ossification of posterior longitudinal ligament were retrospectively reviewed. The Kappa line was defined as a straight line connecting the midpoints of the spinal canal made by remaining bony structure after decompression procedures on a plain lateral radiograph in the neutral position. Patients were classified as K-line (+) or (-) and Kappa line (+) or (-) based on whether the ossified mass crossed the indicator line. The Kappa line (+) group demonstrated significantly higher Japanese Orthopaedic Association (JOA) recovery rate (P=0.01), final JOA score (P<0.01), and dural sac diameter (P<0.01) postoperatively than the Kappa line (-) group. Cord compression grade was significantly lesser in the Kappa line (+) group. However, the K-line-based classification did not demonstrate significant difference in JOA recovery rate, final JOA score, and cord compression grade between the (+) and (-) groups; the dural sac diameter was significantly higher in the K-line (+) group (P<0.01). The Kappa line showed better correlation with ossification of posterior longitudinal ligament size and cervical alignment, providing better prediction of neurological recovery and remaining cord compression following selective LMP. Therefore, the Kappa line can aid in determining the level of decompression in selective LMP.

Comparison of fusion versus non-fusion surgery for retro-odontoid pseudotumor with atlanto-axial subluxation

BackgroundDue to the limited number of reports comparing posterior fusion with posterior decompression alone for retro-odontoid pseudotumor, there remains no consensus on treatment preference, especially in older patients. This study compared posterior fusion (with or without additional decompression) with posterior decompression alone for treating spinal cord pressure from non-inflammatory retro-odontoid pseudotumor with atlanto-axial subluxation (AAS). MethodsForty-one patients (27 male and 14 female; mean age, 73.0 ± 11.4 years) who underwent either posterior cervical fusion or decompression alone for the treatment of non-inflammatory retro-odontoid pseudotumor with AAS and were observed for more than 1 year between September 2009 and July 2019 were enrolled. Thirty-two patients (23 male and 9 female; mean age: 71.8 ± 10.9 years) received posterior fusion surgery (fusion group) and 9 patients (4 male and 5 female; mean age: 77.2 ± 12.5 years) underwent decompression alone (non-fusion group). We compared pre- and postoperative Japanese Orthopaedic Association (JOA) scores and preoperative cervical alignment parameters between the groups. ResultsIn the fusion group, the mean preoperative JOA score was significantly improved from 9.0 ± 3.2 points to 11.7 ± 3.2 points at the final follow-up (p = 0.0002). Similarly in the non-fusion group, the mean preoperative and final follow-up JOA scores were 8.2 ± 3.5 points and 11.7 ± 3.8 points, respectively (p = 0.003). The recovery rate at the final follow-up was 22.6% in the fusion group and 43.4% in the non-fusion group, which were statistically comparable (p = 0.23). We observed no remarkable correlations between cervical sagittal spinal alignment parameters and JOA score recovery rate in the cohort, nor was any significant subluxation progression seen. ConclusionCompared with fusion surgery, surgical decompression alone may be a suitable and less invasive option for the treatment of non-inflammatory retro-odontoid pseudotumor with AAS, especially in elderly patients.

New Grading System for Cervical Paraspinal Soft Tissue Damage After Traumatic Cervical Spinal Cord Injury Without Major Fracture Based on the Short-T1 Inversion Recovery Mid-Sagittal MRI for Prediction of Neurological Improvements: The STIR-MRI Grade.

Retrospective cohort study. To develop a grading method for cervical paraspinal soft tissue damage after cervical spinal cord injury (CSCI) without major fracture based on the short T1 inversion recovery (STIR) mid-sagittal magnetic resonance image (MRI) for prediction of neurological improvements. This study included 34 patients with CSCI without major fracture, treated conservatively for at least 1 year and graded using the STIR-MRI Grade. This system consists of anterior grades; A0: no high-intensity area (HIA), A1: linear HIA, and A2: fusiform HIA, and posterior grades; P0: no HIA, P1: HIA not exceeding the nuchal ligament, and P2: HIA exceeding the nuchal ligament, within 24 hours postinjury. The American Spinal Injury Association impairment scale (AIS) and the Japanese Orthopedic Association (JOA) scores were examined. Anterior grades were not significantly correlated with the AIS and JOA score. At both injury and final follow-up, the AIS in P2 patients was significantly more severe (P = 0.007, P = 0.015, respectively) than that in P0 patients. At the injury, the AIS in P2 patients was significantly more severe (P = 0.008) than that in P1 patients. Among P2 patients only, the JOA score at the injury (1.4 points) did not improve by the final follow-up (3.9 points). The final follow-up JOA score (3.9 points) in P2 patients was significantly lower than that (13.6 points) in P0 patients (P = 0.016). Grade P2 led to poor neurological outcomes. The STIR-MRI Grade is a prognostic indicator for neurological improvements past-CSCI.

Minimum Seven-Year Follow-Up Outcomes of Percutaneous Endoscopic Lumbar Discectomy for Lumbar Degenerative Disease.

PurposeTo investigate the long-term (> 7 years) clinical outcomes of percutaneous endoscopic lumbar discectomy for lumbar degenerative disease to address postoperative problems including postoperative dysesthesia (POD), residual back pain and segmental instability.MethodsInclusion and exclusion criteria were established. All patients who met the above criteria were treated by PELD using the transforaminal approach. Limited discectomy was performed to preserve the disc material in the intervertebral space as much as possible. The Oswestry Disability Index (ODI), Japanese Orthopaedic Association (JOA) score, visual analog scale (VAS) score for back pain (VAS-B) and leg pain (VAS-L) and Modified MacNab’s criterion were used for clinical evaluation. Radiographic parameters including height of intervertebral disc and segmental instability were also evaluated.ResultsForty-two patients (24 men and 18 women) who met our inclusion and exclusion criteria were included in our study. The average follow-up period was 95.71±5.63 months (ranging from 87 to 105 months). There were no neurological complications associated with the operation. POD was found in 14.29% of patients, while only 2 patients (4.76%) complained of mild dysesthesia at final follow-up. Two patients (4.76%) required revision surgery during the follow-up period. The final follow-up ODI, JOA score, VAS-B and VAS-L were significantly better than preoperative values. The average disc-height ratio was 84.52±5.66% of the preoperative disc height. No instability at the operation level was noted at final follow-up.ConclusionOur study showed that PELD using the transforaminal approach can provide favorable results after a long-term follow-up period. POD is a common complication at initial prognosis. Limited discectomy can preserve the disc height well and minimize the risk of residual back pain.

Clinical study of hydraulic perfusion pump and traditional water flushing for percutaneous endoscopic lumbar discectomy

To compare the clinical outcomes of hydraulic perfusion pump and traditional water fhushing in percutaneous endoscopic lumbar discectomy. From January 2016 to December 2018, 72 patients with lumbar disc herniation failed to conservative treatment were enrolled in this study. The patients were divided into hydraulic perfusion pump group and traditional water flushing group, 36 cases in each group. There were no significant differences in gender, age, prominent segment, clinical classification, preoperative visual analogue scale (VAS) and Japanese Orthopaedic Association(JOA) score between two groups (P>0.05). All operations were performed by the same surgeon, and the operations were completed by hydraulic perfusion pumpflushing or traditional water flushing assisted surgery. The operation time, intraoperative blood loss, hospital stay were recorded;VAS and JOA scores were observed before and after operation;the incidences of postoperative complications were compared between two groups. All the patients were followed up for 12 to 24 (15.7±5.1) months. Compared with the traditional water flushing group, the operation time of the hydraulic perfusion pump group was shorter [(65.5±21.3) min vs (74.8±19.9) min, t=9.465, P=0.003], and intraoperative blood loss was less [(21.2±12.9)ml vs (27.4± 14.1) ml, t=8.331, P=0.012], there was no statistical difference in hospital stay between two groups. Postoperative VAS scores at 1 day, 2 weeks and the final follow-up and postoperative JOA scores at the final follow-up of the two groups of patients improved compared with those before operation, but there was no significant difference between two groups (P>0.05). In the traditional water flushing group, the intracranial hypertensionoccurred during operation and the operation time was forced to shorten in 5 cases, the nerve root adventitia injury in 4 cases, and the postoperative recurrence in 4 cases. No intracranial hypertension during operation was found in the hydraulic perfusion pump group, nerve root adventitia injury occurred in 1 case, postoperative recurrence in 2 cases. The incidence of complication of the hydraulic perfusion pump group was lower than that ofthe traditional water flushing group. Both hydraulic perfusion pump and traditional water flushing assisted percutaneous endoscopic lumbar disc herniation can achieve satisfactory clinical results, but the former has shorter operation time, clearer intraoperative vision, less bleeding, and fewer intraoperative and postoperative complications.

Significance of Vertebral Body Sliding Osteotomy as a Surgical Strategy for the Treatment of Cervical Ossification of the Posterior Longitudinal Ligament.

Study Design:Retrospective cohort study.Objectives:Vertebral body sliding osteotomy (VBSO) has previously been reported as a technique to decompress ossification of the posterior longitudinal ligament (OPLL) by translating the vertebral body anteriorly. This study aimed to evaluate the radiological and clinical efficacies of VBSO and clarify the surgical indications of VBSO for treating myelopathy caused by OPLL.Methods:Ninety-seven patients with symptomatic OPLL-induced cervical myelopathy treated with VBSO or laminoplasty who were followed up for more than 2 years were retrospectively reviewed. Cervical alignment, range of motion, fusion, modified K-line (mK-line) status, and minimum interval between ossified mass and mK-line (INT(min)), and the Japanese Orthopaedic Association (JOA) score were assessed. Patients in the VBSO group were compared with those who underwent laminoplasty.Results:Cervical lordosis and INT(min) significantly increased in the VBSO group. All patients in the VBSO group assessed as mK-line (-) preoperatively were assessed as mK-line (+) postoperatively. However, in the LMP group, the mK-line status changed from (+) preoperatively to (−) postoperatively in 3 patients. Final JOA score (p = 0.02) and JOA score improvement (p = 0.01) were significantly higher in the VBSO group. JOA recovery ratio (p = 0.03) and proportion of patients with a recovery rate ≥50% were significantly higher in the VBSO group (p < 0.01).Conclusions:VBSO is an effective surgical option for OPLL-induced myelopathy, demonstrating favorable neurological recovery and lordosis restoration with low complication rates. It is best indicated for kyphotic alignment, OPLL with a high space-occupying ratio, and OPLL involving ≤3 segments.

Analysis of the spinal cord angle for severe cervical ossification of the posterior longitudinal ligament: comparison between anterior controllable antedisplacement and fusion (ACAF) and posterior laminectomy.

To investigate the changes of spinal cord angle between anterior controllable antedisplacement and fusion (ACAF) and posterior laminectomy in treating severe ossification of the posterior longitudinal ligament (OPLL). Seventy-one patients with cervical OPLL were enrolled. Patients in this study were divided into group A and group P. Japanese Orthopaedic Association (JOA) score was utilized to evaluate the neurological function. Radiological assessments included the spinal cord angle, Cobb angle, and area of the spinal cord. Surgery-related complications were also recorded. At the final follow-up, patients in group A had better recovery of local and whole cord angle, and the area of the cord than those in group P (all p < 0.05). A strong correlation between the change of local cord angle and the recovery of the spinal cord area was observed (r = - 0.867, p < 0.05). In addition, patients in group P had worse Cobb angle (9.15° ± 1.10°) than in group A (18.58° ± 0.73°) (p < 0.05). The final mean JOA score and its improvement rate were better in the group A than in group P (p < 0.05). During the follow-up, 15.15% patients in group P experienced surgery-related complications and 7.89% in group A. This present study revealed that ACAF can achieve better recovery of the expansion of the spinal cord, spinal cord alignment, and Cobb angle, with better postoperative JOA score and less complications, compared with posterior laminectomy in treating severe cervical OPLL. These slides can be retrieved under Electronic Supplementary Material.

A Novel Inextensible Endoscopic Tube Versus Traditional Extensible Retractor System in Single-Level Minimally Invasive Transforaminal Lumbar Interbody Fusion: A Prospective Observation Study

Background: Currently, various retractor systems are widely used for access to the lumbar spine in minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF). Nevertheless, studies concerning the comparison of extensible retractor and inextensible tube systems are quite rare. Objectives: This article was to compare perioperative characteristics, clinical outcomes, and multifidus muscle injury of obconic inextensible tube versus extensible retractor system for singlelevel MIS-TLIF. Study Design: A prospective observational study on 91 patients with a mean follow-up of 20.0 ± 4.1 months. Setting: This study was conducted by a university-affiliated hospital in a major Chinese city. Methods: From April 2015 to May 2016, 91 consecutive patients who underwent MIS-TLIF procedure using an obconic inextensible endoscopic tube or extensible retractor system were enrolled in this study. Operation parameters such as incision length, blood loss, postoperative drainage volume, surgical time, analgesic use rate, time to ambulation, and postoperative hospitalization days were evaluated. The concentration of white blood cells, c-reactive protein (CRP) interleukin-6, interleukin-8, tumor necrosis factor alpha, and creatine phosphokinase (CPK)- MM of the enrolled patients were measured for postoperative traumatic stress and muscle injury. Multifidus muscle edema and atrophy were evaluated by T2-weighted magnetic resonance imaging (MRI) at 3 different time points (preoperative, postoperative, and 1-year follow-up). Clinical outcomes such as Visual Analog Scale (VAS) score, Japanese Orthopedic Association (JOA) score, Oswestry Disability Index (ODI) score, fusion rates, and MacNab criteria were assessed for patients’ symptoms. Results: In terms of baseline characteristics, the 2 groups were similar regarding sample size, gender, age, symptoms duration, operation level, body mass index, physical examination, and all the clinical outcomes measures (P &gt; 0.05). Perioperative analysis showed that the inextensible group had comparative incision length, blood loss, operation time, time to ambulation, and postoperative hospitalization (P &gt; 0.05). The inextensible tubular group had less postoperative drainage volume and analgesic use rate (P &lt; 0.05). The concentration level of CPK-MM and CRP was lower in the inextensible tubular group compared with the extensible retractor group. No significant difference was found between the 2 groups regarding MRI T2 signal intensity ratio of multifidus muscle at the immediate postoperative period. The MRI T2 signal intensity ratio of multifidus muscle was lower in the inextensible tubular group than the extensible retractor group at the 1-year follow-up period. The VAS scores for low back pain and leg pain improved significantly in both groups after surgery, as did the JOA and ODI scores. However, there were no significant differences between the 2 groups regarding the preoperative and final follow-up VAS, JOA, and ODI scores, fusion rates, and the distribution of the MacNab criteria. Limitations: This was not a randomized controlled trail, which could provide more evidence-based medicine conclusions. Conclusions: The obconic inextensible endoscopic tube system via the transforaminal approach for lumbar interbody fusion is a safe and sufficient technique. When compared with the extensible retractor system, it has comparable clinical outcomes, with additional significant benefits of less postoperative drainage volume and analgesic use rate, less multifidus muscle injury in terms of lower CPK-MM levels at immediate postoperative period, less change in CRP, and less change in MRI T2 signal intensity ratio of multifidus muscles at 1-year follow-up.

Recovery Process After Anterior Cervical Decompression in Patients With Cervical Spondylotic Myelopathy With Different Natural History.

An observational prospective cohort study. To investigate the influence of natural history on the recovery of patients with cervical spondylotic myelopathy (CSM) after anterior cervical decompression. The natural history of CSM has not been clearly elucidated, it remains unclear whether the natural history of CSM is associated with the recovery process after surgical treatment. Patients with CSM (n=117) after anterior cervical decompression were stratified variously on the basis of natural history features. Baseline and postoperative neurological functions were rated using the Japanese Orthopaedic Association (JOA) and patient-based self-evaluation (PBSE) scores. The minimum and maximum recovery times for sensory function, and motor functions of the upper and lower extremities were analyzed separately at time points 1-60 months after surgery. In all patients, the postoperative JOA and PBSE scores were significantly improved relative to baseline, in which sensory function recovered most quickly, followed by upper-extremity and lower-extremity motor functions. However, when compared with patients whose first symptom onset at the lower extremity, patients with the first onset at the upper extremity required less time to recover lower-extremity motor function, but more time to recover upper-extremity motor function. Patients with rapid progression had significantly lower preoperative and final JOA and PBSE scores compared with patients whose progression was steady or stepwise. Patients with preoperative symptoms ≥1 year had longer recovery time and poorer functional outcomes compared with those symptoms <1 year. In patients with CSM, the location of first symptom onset, progressive velocity of symptom, and duration of preoperative symptoms significantly influenced the recovery process after anterior cervical decompression. Level 2-observational prospective study.

Surgical Results of Patients with Myelopathy due to Ossification of the Ligamentum Flavum with Ossification of the Posterior Longitudinal Ligament or a Vertebral Fracture at the Same Level of the Thoracic Spine: A Retrospective Comparative Study.

Study DesignRetrospective and comparative study.PurposeWe assessed surgical treatment outcomes in patients with thoracic myelopathy due to ossification of the ligamentum flavum (OLF), and OLF combined with ossification of the posterior longitudinal ligament (OPLL) or vertebral fracture (VF) at the same level.Overview of LiteratureOLF and OPLL cause severe thoracic myelopathy. Osteoporotic VF commonly occurs at the thoracolumbar junction. There have been no investigations of thoracic myelopathy due to OLF and VF.MethodsForty patients were divided among three groups: the OLF group (n=23): myelopathy due to OLF, the OLF+OPLL group (n=12): myelopathy due to OLF and OPLL, and the OLF+VF group (n=5): myelopathy due to OLF and VF. We recorded OLF, OPLL, and VF sites and operative procedures. Each patient’s neurological status, according to the Japanese Orthopaedic Association (JOA) score, and walking ability were evaluated pre- and postoperatively.ResultsPatients in the OLF+OPLL group were significantly younger than those in the other two groups. The preoperative JOA score was significantly lower in the OLF+VF than OLF group. The final JOA score was significantly lower in the OLF+VF than OLF and OLF+OPLL groups. The JOA score recovery rate was significantly lower in the OLF+VF than OLF group. Final walking ability was significantly worse in the OLF+OPLL and OLF+VF groups than in the OLF group and significantly worse in the OLF+VF than OLF+OPLL group.ConclusionsThoracic myelopathy due to OLF+VF occurs primarily in older females, who also exhibit worse preoperative and postoperative neurological status, and worse walking ability, than patients with thoracic myelopathy due to OLF or OLF+OPLL.

Effects of decompressive operation on cardiac autonomic regulation in patients with cervical spondylotic myelopathy: analysis of blood pressure, heart rate, and heart rate variability.

To investigate the effects of cervical decompression operation on cardiac autonomic regulation and its relationship to recovery of somatic neurological function in cervical spondylotic myelopathy (CSM) patients. One hundred and thirty-two consecutive patients were enrolled in this study, in which 73 patients received decompression operation and the remaining 59 were treated non-operatively. The follow-up period was 6months. Baseline and follow-up evaluation included Japanese Orthopaedic Association (JOA) score, office-based blood pressure (BP) measurement, heart rate (HR), and 24-h heart rate variability (HRV) assessment. Relationship between achieved JOA score (final JOA score-baseline score) and changes of BP, HR, and HRV parameters in both operative and non-operative groups was analyzed. In operative group, patients' JOA score and markers of parasympathetic activity in HRV assessment were significantly higher than baseline level 6months later. Blood pressure, especially systolic blood pressure (SBP), was significantly downregulated in both hypertension and non-hypertension patients. Mean heart rate was also significantly decreased. Furthermore, achieved JOA score was significantly negatively correlated with changes of SBP, minimal HR, mean HR, maximum HR, but significantly positively correlated with changes of HRV parameters reflecting parasympathetic activity. However, changes of JOA score, BP, HR, and HRV parameters in non-operative group were not significant. Cervical decompression operation could improve both somatic neurological function and cardiac autonomic regulation in CSM patients, and achieved JOA score was significantly positively correlated with improvement in HRV and cardiac parasympathetic activity. These slides can be retrieved under Electronic Supplementary Material.