Basivertebral nerve ablation with concurrent lumbar laminotomy.

Lumbar radiculopathy due to impingement of nerve roots from facet hypertrophy and/or disc herniation can often coincide with vertebrogenic low back pain. This is demonstrated on MRI with foraminal stenosis and Modic changes. We examine the potential of using a combination of basivertebral nerve ablation (BVNA) and lumbar laminotomy as an alternative to traditional spinal fusion in specific patient populations. This unique combination of surgical techniques has not been previously reported in the medical literature. We report a man in his late 30s with chronic low back pain and lumbar radiculopathy, treated with BVNA and concurrent laminotomy. The patient reported progressive improvements in his mobility and pain over the next 2 years. We discuss the advantages of using this technique for lumbar radiculopathy and Modic changes compared with conventional surgical modalities.

A rare case of spontaneous giant pneumorrachis presenting with cauda equina syndrome: a case report.

INTRODUCTION: Pneumorrachis is presence of air in the epidural space. It could be the result of trauma, barotrauma, iatrogenic or spontaneous. The pneumorrachis per se is an underdiagnosed entity as most of the patients are asymptomatic or have subclinical symptoms. The spontaneous occurrence of pneumorrachis has been reported in literature but giant spontaneous occurrence causing cauda equina syndrome has not been reported so far. CASE PRESENTATION: We report a case of 56-year-old male patient who came to our OPD on wheelchair with complains of difficulty in walking for 6 months with dribbling of urine for 2 months with on and off back pain. His perianal sensation was reduced with absent voluntary anal contraction. Imaging revealed giant air pockets in the spinal canal of L5-S1 extending upto L4-L5. It was managed surgically wherein laminectomy without fusion was done. The patient responded well to the treatment. DISCUSSION: There are many causes of pneumorrachis described in literature. Most of the cases of pneumorrachis are asymptomatic and incidentally diagnosed. With the improvement in radio-diagnostic modalities, the diagnosis of pneumorrachis can be easily established. When symptomatic, they can be managed conservatively. Those presenting with neurological deficit may require surgical intervention or other invasive intervention.

Vertebral artery dissection as the underlying cause of ventral spinal epidural haematoma.

Spontaneous spine epidural haematoma is a rare occurrence, with an incidence of 0.1/100 000 inhabitants/year. The anterior location of the haematoma is very uncommon since the dural sac is firmly attached to the posterior longitudinal ligament. Vertebral artery dissection as its underlying cause is an exceptionally rare event, with only two documented cases.This article presents the case of young woman who arrived at the emergency room with a spinal ventral epidural haematoma extending from C2 to T10, caused by a non-traumatic dissecting aneurysm of the right vertebral artery at V2-V3 segment. Since the patient was tetraparetic, she underwent emergent laminectomy, and the vertebral artery dissection was subsequently treated endovascularly with stenting.Vertebral artery dissection with subsequent perivascular haemorrhage is a possible cause of spontaneous spine epidural haematoma, particularly when located ventrally in the cervical and/or high thoracic column. Hence the importance of a thorough investigation of the vertebral artery integrity.

Biomechanical response of decompression alone in lower grade lumbar degenerative spondylolisthesis--A finite element analysis.

BACKGROUND: Previous studies have demonstrated the clinical efficacy of decompression alone in lower-grade spondylolisthesis. A higher rate of surgical revision and a lower rate of back pain relief was also observed. However, there is a lack of relevant biomechanical evidence after decompression alone for lower-grade spondylolisthesis. PURPOSE: Evaluating the biomechanical characteristics of total laminectomy, hemilaminectomy, and facetectomy for lower-grade spondylolisthesis by analyzing the range of motion (ROM), intradiscal pressure (IDP), annulus fibrosus stress (AFS), facet joints contact force (FJCF), and isthmus stress (IS). METHODS: Firstly, we utilized finite element tools to develop a normal lumbar model and subsequently constructed a spondylolisthesis model based on the normal model. We then performed total laminectomy, hemilaminectomy, and one-third facetectomy in the normal model and spondylolisthesis model, respectively. Finally, we analyzed parameters, such as ROM, IDP, AFS, FJCF, and IS, for all the models under the same concentrate force and moment. RESULTS: The intact spondylolisthesis model showed a significant increase in the relative parameters, including ROM, AFS, FJCF, and IS, compared to the intact normal lumbar model. Hemilaminectomy and one-third facetectomy in both spondylolisthesis and normal lumbar models did not result in an obvious change in ROM, IDP, AFS, FJCF, and IS compared to the pre-operative state. Moreover, there was no significant difference in the degree of parameter changes between the spondylolisthesis and normal lumbar models after undergoing the same surgical procedures. However, total laminectomy significantly increased ROM, AFS, and IS and decreased the FJCF in both normal lumbar models and spondylolisthesis models. CONCLUSION: Hemilaminectomy and one-third facetectomy did not have a significant impact on the segment stability of lower-grade spondylolisthesis; however, patients with LDS undergoing hemilaminectomy and one-third facetectomy may experience higher isthmus stress on the surgical side during rotation. In addition, total laminectomy changes the biomechanics in both normal lumbar models and spondylolisthesis models.

Full endoscopic laminotomy decompression versus anterior cervical discectomy and fusion for the treatment of single-segment cervical spinal stenosis: a retrospective, propensity score-matched study.

OBJECTIVE: Anterior cervical discectomy and fusion (ACDF) is the standard procedure for the treatment of cervical spinal stenosis (CSS), but complications such as adjacent segment degeneration can seriously affect the long-term efficacy. Currently, posterior endoscopic surgery has been increasingly used in the clinical treatment of CSS. The aim of this study was to compare the clinical outcomes of single-segment CSS patients who underwent full endoscopic laminotomy decompression or ACDF. METHODS: 138 CSS patients who met the inclusion criteria from June 2018 to August 2020 were retrospectively analyzed and divided into endoscopic and ACDF groups. The propensity score matching (PSM) method was used to adjust the imbalanced confounding variables between the groups. Then, perioperative data were recorded and clinical outcomes were compared, including functional scores and imaging data. Functional scores included Visual Analog Scale of Arms (A-VAS) and Neck pain (N-VAS), Japanese Orthopedic Association score (JOA), Neck Disability Index (NDI), and imaging data included Disc Height Index (DHI), Cervical range of motion (ROM), and Ratio of grey scale (RVG). RESULTS: After PSM, 84 patients were included in the study and followed for 24-30 months. The endoscopic group was significantly superior to the ACDF group in terms of operative time, intraoperative blood loss, incision length, and hospital stay (P < 0.001). Postoperative N-VAS, A-VAS, JOA, and NDI were significantly improved in both groups compared with the preoperative period (P < 0.001), and the endoscopic group showed better improvement at 7 days postoperatively (P < 0.05). The ROM changes of adjacent segments were significantly larger in the ACDF group at 12 months postoperatively and at the last follow-up (P < 0.05). The RVG of adjacent segments showed a decreasing trend, and the decrease was more marked in the ACDF group at last follow-up (P < 0.05). According to the modified MacNab criteria, the excellent and good rates in the endoscopic group and ACDF group were 90.48% and 88.10%, respectively, with no statistically significant difference (P > 0.05). CONCLUSION: Full endoscopic laminotomy decompression is demonstrated to be an efficacious alternative technique to traditional ACDF for the treatment of single-segment CSS, with the advantages of less trauma, faster recovery, and less impact on cervical spine kinematics and adjacent segmental degeneration.

Biportal endoscopic cervical open-door laminoplasty to treat cervical spondylotic myelopathy.

BACKGROUND: Although cervical laminoplasty is a frequently utilized surgical intervention for cervical spondylotic myelopathy, it is primarily performed using conventional open surgical techniques. We attempted the minimally invasive cervical laminoplasty using biportal endoscopic approach. METHODS: Contralateral lamina access is facilitated by creating space through spinous process drilling, followed by lamina hinge formation. Subsequently, the incised lamina is elevated from ipsilateral aspect, and secure metal plate fixation is performed. CONCLUSION: We successfully performed the cervical open door laminoplasty using biportal endoscopic approach. Biportal endoscopic cervical open-door laminoplasty may be a minimally invasive technique that can prevent complications related with open surgery.

Racial and Socioeconomic Disparities in Laminoplasty Versus Laminectomy With Fusion in Patients With Cervical Spondylosis.

STUDY DESIGN: A retrospective cohort study using prospectively collected data. OBJECTIVE: The aim of this study was to investigate preoperative differences in racial and socioeconomic factors in patients undergoing laminoplasty (LP) versus laminectomy and fusion (LF) for degenerative cervical myelopathy (DCM). SUMMARY OF BACKGROUND DATA: DCM is prevalent in the United States, requiring surgical intervention to prevent neurological degeneration. While LF is utilized more frequently, LP is an emerging alternative. Previous studies have demonstrated similar neurological outcomes for both procedures. However, treatment selection is primarily at the discretion of the surgeon and may be influenced by social determinants of health that impact surgical outcomes. MATERIALS AND METHODS: The Quality Outcome Database (QOD), a national spine registry, was queried for adult patients who underwent either LP or LF for the management of DCM. Covariates associated with socioeconomic status, pain and disability, and demographic and medical history were collected. Multivariate logistic regression was performed to assess patient factors associated with undergoing LP versus LF. RESULTS: Of 1673 DCM patients, 157 (9.4%) underwent LP and 1516 (90.6%) underwent LF. A significantly greater proportion of LP patients had private insurance (P<0.001), a greater than high school level education (P<0.001), were employed (P<0.001), and underwent primary surgery (P<0.001). LP patients reported significantly lower baseline neck/arm pain and Neck Disability Index (P<0.001). In the multivariate regression model, lower baseline neck pain [odds ratio (OR)=0.915, P=0.001], identifying as non-Caucasian (OR=2.082, P<0.032), being employed (OR=1.592, P=0.023), and having a greater than high school level education (OR=1.845, P<0.001) were associated with undergoing LP rather than LF. CONCLUSIONS: In DCM patients undergoing surgery, factors associated with patients undergoing LP versus LF included lower baseline neck pain, non-Caucasian race, higher education, and employment. While symptomatology may influence the decision to choose LP over LF, there may also be socioeconomic factors at play. The trend of more educated and employed patients undergoing LP warrants further investigation.

Practice variation in surgical treatment for lumbar degenerative disc disease: exploring regional and hospital factors influencing surgical rates.

The presence of significant, unwarranted variation in treatment suggests that clinical decision making also depends on where patients live instead of what they need and prefer. Historically, high practice variation in surgical treatment for lumbar degenerative disc disease (LDDD) has been documented. This study aimed to investigate current regional variation in surgical treatment for sciatica resulting from LDDD. We conducted a retrospective, cross-sectional analysis of all Dutch adults (>18 years) between 2016 and 2019. Demographic data from Statistics Netherlands were merged with a nationwide claims database, covering over 99% of the population. Inclusion criteria comprised LDDD diagnosis codes and relevant surgical codes. Practice variation was assessed at the level of postal code areas and hospital service areas (HSAs). Multivariable logistic regression analysis was employed to identify variables associated with surgical treatment. Among the 119,148 hospital visitors with LDDD, 14,840 underwent surgical treatment. Practice variation for laminectomies and discectomies showed less than two-fold variation in both postal code and HSAs. However, instrumented fusion surgery demonstrated a five-fold variation in postal code areas and three-fold variation in HSAs. Predictors of receiving surgical treatment included opioid prescription and patient referral status. Gender differences were observed, with males more likely to undergo laminectomy or discectomy, and females more likely to receive instrumented fusion surgery. Our study revealed low variation rates for discectomies and laminectomies, while indicating a high variation rate for instrumented fusion surgery in LDDD patients. High-quality research is needed on the extent of guideline implementation and its influence on practice variation.

Ultrasonic bone curette-assisted unilateral approach for bilateral decompression with MIS-TLIF for severe lumbar spinal stenosis.

PURPOSE: We aimed to evaluate the clinical efficacy of bilateral decompression with minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) assisted by an ultrasonic bone curette (UBC) for treating severe degenerative lumbar spinal stenosis (DLSS) and traditional tool laminectomy decompression MIS-TLIF for treating severe DLSS. METHODS: The clinical data of 128 patients with single-segment severe DLSS who were admitted between January 2017 and December 2021 were retrospectively analyzed. Among them, 67 patients were treated with unilateral fenestration and bilateral decompression MIS-TLIF using an ultrasonic bone curette (UBC group), whereas 61 patients were treated with unilateral fenestration and bilateral decompression MIS-TLIF using traditional tools (traditional group, control). A visual analog scale (VAS) was used to evaluate back and lower limb pain before the operation,immediate postoperative, and one week, 3, 6, 12, and 24 months after the operation. Oswestry disability index (ODI) and Zurich claudication score (ZCQ) were employed to evaluate the improvement in low back and lower limb function. At the last follow-up, the Bridwell bone graft fusion standard was utilized to evaluate bone graft fusion. RESULTS: The decompression time of laminectomy was significantly shorter in the UBC group than in the traditional group (control group), and the intraoperative blood loss and postoperative drainage volume were significantly less in those in the control group (P < 0.05). The VAS, ODI, and ZCQ scores of the two groups after the operation were significantly improved compared to those before the operation (P < 0.05). The UBC group had better VAS back scores than the control group immediate postoperative and one week after the operation(P < 0.05). The UBC group had better VAS lower limb scores than the control group immediate postoperative (P < 0.05).The incidence of perioperative complications, hospitalization time, dural sac cross-sectional area (CSA), and dural sac CSA improvement rate did not differ significantly between the two groups (P > 0.05). VAS and ODI scores did not differ significantly between the two groups before,three, six months, one year, and two years after surgery (P > 0.05). The ZCQ scores did not differ significantly between the two groups before the operation at one week, six months, one year, and two years after the operation (P > 0.05). According to the Bridwell bone graft fusion standard, bone graft fusion did not occur significantly between the two groups (P > 0.05) at the last follow-up. CONCLUSIONS: UBC unilateral fenestration bilateral decompression MIS-TLIF in treating severe DLSS can achieve clinical efficacy as traditional tool unilateral fenestration bilateral decompression MIS-TLIF and reduce intraoperative blood loss and postoperative drainage. It can also shorten the operation time, effectively reduce the work intensity of the operator, and reduce the degree of low back pain during short-term follow-ups. Therefore, this is a safe and effective surgical method.

Quantitative Anatomic Analysis and Clinical Application of Lumbar Spinous Process Split Laminotomy.

AIM: To investigate the feasibility and safety of lumbar spinous process split laminotomy by quantitative anatomic analysis. MATERIAL AND METHODS: Nine fresh adult human cadaveric specimens (including 45 lumbar segments) were divided into 3 groups randomly. The simulated operations and anatomic measurements were performed to evaluate the visibility angle and surgical corridor at different retraction widths (8 mm, 10 mm, and 12 mm). By measuring the width causing bony fracture in 45 lumbar segments, the safety margin of retraction width was determined. The findings of lumbar spinous process split laminotomy in one typical case were presented. RESULTS: At 8 mm retraction width, there was not enough surgical corridor for the operation procedures. At 10 mm and 12 mm retraction width, all operation procedures could be conducted smoothly. The 12 mm group presented a larger surgical corridor and shorter operative time compared with the 10 mm group. The imaging examination confirmed no bony fracture and articular capsule impairment. The visibility angle and exposure extent increased in proportion to the retraction width. The retraction width that resulted in the bony fracture ranged from 12.34 mm to 16.82 mm, with an average of (14.56 ± 1.73) mm. The positions of fracture were in the pedicle of the vertebral arch (68.9%), the lamina (26.7%), and the vertebral body (4.4%). CONCLUSION: The retraction width of 10 mm-12 mm is safe and effective. The micromanipulations such as tumor resection, nervous exploration, dural suture, etc. can be conducted smoothly via the surgical corridor. In addition, the retraction width of 12.34~16.82 mm could serve as a safety margin for surgical planning. Our findings may provide a quantitative reference for clinical application of lumbar spinous process split laminotomy.

Conjoined lumbosacral nerve root: a case report.

BACKGROUND: In patients with conjoined nerve roots, hemilaminectomy with sufficient exposure of the intervertebral foramen or lateral recess is required to prevent destabilization and ensure correct mobility of the lumbosacral spine. To the best of our knowledge, no case reports have detailed the long-term course of conjoined nerve roots after surgery. CASE PRESENTATION: We report the case of a 51-year-old Japanese man with a conjoined nerve root. The main symptoms were acute low back pain, radiating pain, and right leg muscle weakness. Partial laminectomy was performed with adequate exposure to the conjoined nerve root. The symptoms completely resolved immediately after surgery. However, the same symptoms recurred 7 years postoperatively. The nerve root was compressed because of foraminal stenosis resulting from L5-S disc degeneration. L5-S transforaminal lumbar interbody fusion was performed on the contralateral side because of an immobile conjoined nerve root. At 44 months after the second surgery, the patient had no low back pain or radiating pain, and the muscle weakness in the right leg had improved. CONCLUSIONS: This is the first report of the long-term course of conjoined nerve root after partial laminectomy. When foraminal stenosis occurs after partial laminectomy, transforaminal lumbar interbody fusion from the contralateral side may be required because of an immobile conjoined nerve root.

Congenital hemivertebrae combined with situs inversus totalis: A rare case report.

RATIONALE: Situs inversus totalis is a rare malposition of organs that typically involves lesions in the respiratory, circulatory, or urinary systems. Cases of congenital hemivertebrae combined with situs inversus totalis are extremely rare and have limited reports. PATIENT CONCERNS: We report a 2.5 years old girl with 2 congenital hemipyramids and complete visceral inversion who ultimately underwent hemilaminectomy. DIAGNOSIS: Congenital hemivertebrae combined with situs inversus totalis. INTERVENTION: The patient underwent hemilaminectomy. OUTCOMES: The spinal deformity was corrected. LESSONS: For patient with spinal deformities combined with situs inversus totalis, surgery can be an effective treatment method. But we also need to be vigilant about the dysfunction of various systems.

Retrospective Study to Compare the Effectiveness of Minimally Invasive Microscopic Unilateral Laminotomy with Microscopic Bilateral Laminotomy for Bilateral Decompression in the Early Postoperative Period in 142 Patients with Single-Level Lumbar Spinal Stenosis.

BACKGROUND We aimed to compare the effectiveness of microscopic unilateral laminotomy for bilateral decompression (ULBD) and microscopic bilateral laminotomy for bilateral decompression (BLBD) in the early postoperative period among patients with single-level lumbar spinal stenosis (LSS). MATERIAL AND METHODS A retrospective cohort study was conducted on patients with LSS who underwent ULBD or BLBD between January 2020 and December 2023, including 94 patients who underwent ULBD and 58 who underwent BLBD. Patient demographics, comorbidities, smoking status, and data related to LSS were reviewed. Preoperative and postoperative assessments on day 10 included back pain visual analog scale (VAS), walking distance, and Odom criteria. Disability was evaluated using the self-assessment Oswestry Disability Index (ODI) preoperatively and on day 30. Additionally, wound infection, postoperative modified MacNab criteria, and pain (back, leg, and hip) were recorded. RESULTS Age and sex were similar in the 2 groups. Both surgeries significantly reduced low back pain, increased walking distance, and improved Odom category on day 10, compared with baseline (P<0.001 for all). A significant decrease in 30-day ODI, compared with baseline, was observed in both groups (P<0.001 for both). The ULBD group had a significantly higher percentage of patients with wound infection (P=0.014); however, the ODI score among ULBD recipients was significantly lower (better) on day 30 (P=0.047). CONCLUSIONS ULBD may represent a less invasive, more effective, and safer surgical alternative than BLBD and classical laminectomy in patients with single-level LSS, but precautions are essential concerning wound infection.

Clinical effects of arthroscopic-assisted uni-portal spinal surgery and unilateral bi-portal endoscopy on unilateral laminotomy for bilateral decompression in patients with lumbar spinal stenosis: a retrospective cohort study.

OBJECTIVE: To investigate the clinical effectiveness of Arthroscopic-assisted Uni-portal Spinal Surgery (AUSS) in the treatment of lumbar spinal stenosis. METHODS: A total of 475 patients with lumbar spinal stenosis from January 2019 to January 2023 were included in this study. Among them, 240 patients were treated with AUSS (AUSS group); the other 235 patients were treated with unilateral bi-portal endoscopy treatment (UBE group). The differences in surgery-related clinical indicators, pain degree before and after surgery, Oswestry Disability Index (ODI), CT imaging parameters of spinal stenosis, and clinical efficacy were compared between the two groups. RESULTS: Patients in the AUSS group had a shorter operative time than those in the UBE group, and the length of incision and surgical bleeding were less than those in the UBE group, with statistically significant differences (P < 0.05). Before operation, there was no significant difference in the VAS score of low back pain and leg pain between the two groups (P > 0. 05). After operation, patients in both groups showed a significant reduction in low back and leg pain, and their VAS scores were significantly lower than before the operation (P < 0.05). Three months after surgery, the results of CT re-examination in both groups showed that the spinal stenosis of the patients was well improved, and the measurements of lumbar spinal interspace APDC, CAC, ICA, CAD and LAC were significantly higher than those before surgery (P < 0. 05). Besides, the lumbar function of patients improved significantly in both groups, and ODI measurements were significantly lower than those before surgery (P < 0.05). CONCLUSION: Both AUSS and UBE with unilateral laminotomy for bilateral decompression can achieve good clinical results in the treatment of lumbar spinal stenosis, but the former has the advantages of simpler operation, shorter operation time, shorter incision length, and less surgical blood loss.

Simultaneous spine extradural and intradural teratomas in a pediatric patient: A rare presentation with insights in the flawed migration of germ cells theory.

Spinal teratomas are infrequent lesions in the pediatric population. These lesions can be extradural, intradural or intramedullary. We present a case of an 8-month-old boy that was assessed for underdevelopment of motor milestones. The neurologic examination revealed hyporeflexia, decreased sensation and flaccid paraplegia. MRI of the spine revealed two simultaneous and independent lesions in the extradural and intradural compartment. A laminectomy was performed for the T4-T7 vertebrae with total resection of both lesions. The histopathological analysis confirmed both lesions to be mature cystic teratomas. At the 1-year follow-up, the patient remained with no recovery of neurological function. A debate takes place regarding the etiology of formation of these lesions in the spine. The simultaneous presentation of two independent lesions in this patient could contribute to define the flawed migration of germ cells theory as the etiology for formation of teratomatous lesions in the spine.

Biportal endoscopic transforaminal thoracic interbody fusion for the treatment of thoracic myelopathy.

BACKGROUND: Biportal endoscopic spine surgery independently controls two hands, similar to microscopic surgery, and utilizes a broader working space that is not disturbed by retractors under clear-magnified endoscopic vision. These advantages facilitate successful neural decompression and safe transforaminal interbody fusion, even in patients with thoracic spondylotic myelopathy. METHODS: A wide laminectomy and precise total facetectomy, in conjunction with partial pediculotomy, establish a secure transforaminal space for cage insertion. Endplate preparation and cage insertion were performed without retracting the spinal cord under direct endoscopic vision. CONCLUSION: Biportal endoscopic transforaminal thoracic interbody fusion can be a feasible technique for treating thoracic spondylotic myelopathy at the thoracolumbar junction levels.

Thoracic Vertebral Canal Stenosis and Vertebral Instability in a Young Minuet Cat.

This report describes a unique case of thoracic vertebral canal stenosis and vertebral instability in a 1 yr old Minuet cat. The cat presented with a history of chronic progressive nonambulatory paraparesis. Myelography with neutral and stress positions revealed dynamic compression at T1-4. Computed tomography and MRI revealed multiple sites of vertebral endplate osteolysis, adjacent bone sclerosis, intervertebral disk space narrowing, and spondylotic bridging within the cervical and cranial thoracic vertebral bodies and pedicles, particularly at C6-T4. The cat underwent a right-sided T1-4 hemilaminectomy and C7-T4 vertebral stabilization using positively threaded profile pins and polymethylmethacrylate. The cat fully recovered without any complication. The case highlights the potential for young cats, especially those with a chondrodysplastic condition, to develop vertebral canal stenosis and vertebral instability. The surgical treatment described herein resulted in an excellent outcome.

Clinical features of early recurrence of type I thoracolumbar intervertebral disk herniation in Miniature Dachshunds.

Some reports have been published on clinical features in dogs with early recurrence of type I thoracolumbar intervertebral disk herniation (TL-IVDH), but there is little understanding of the changes involved. This retrospective study describes the clinical features, including radiographic image results at the time of recurrence, of dogs with type I TL-IVDH that had undergone hemilaminectomy but then suffered early recurrence. Our medical records were searched between June 2007 and December 2022. Nine dogs showed deterioration in neurological signs within 4 to 6 weeks after surgery. All nine were Miniature Dachshunds. Radiographic images at initial onset showed calcification at the affected intervertebral disk space in all 9 dogs. Disk herniations at the initial onset were located between T11-12 and L1-2. After the first surgery, neurological function improved in all dogs. Recurrence occurred at the same site as at initial onset in all dogs. No calcification was observed at the affected intervertebral disk space on images at the time of recurrence. The extruded disk materials were surgically removed, and neurological function improved after the second surgery. In conclusion, calcification at the affected disk space at the time of initial onset is indicative of residual nucleus materials not yet fully extruded, and is a risk factor for early recurrence of type I TL-IVDH.

What Happens to Sagittal Alignment Following Laminoplasty Versus Laminectomy and Fusion?

OBJECTIVE: Laminectomy and fusion (LF) and laminoplasty (LP) are 2 sucessful posterior decompression techniques for cervical myelo-radiculopathy. There is also a growing body of evidence describing the importance of cervical sagittal alignment (CSA) and its importance in outcomes. We investigated the difference between pre- and postoperative CSA parameters in and between LF or LP. Furthermore, we studied predictive variables associated with change in cervical mismatch (CM). METHODS: This is a retrospective cohort study of adults with cervical myeloradiculopathy in a single healthcare system. The primary outcomes are intra- and inter-cohort comparison of LF versus LP radiographic parameters at pre- and postoperative time points. A secondary multivariable analysis of predictive factors was performed evaluating factors predicting postoperative CM. RESULTS: Eighty nine patients were included; 38 (43%) had LF and 51 (57%) underwent LP. Both groups decreased in lordosis (LF 11.4° vs. 4.9°, P = 0.01; LP 15.2° vs. 9.1°, P < 0.001), increased in cSVA (LF 3.4 vs. 4.2 cm, P = 0.01; LP 3.2 vs. 4.2 cm, P < 0.001), and increased in CM (LF 22.0° vs. 28.5°, P = 0.02; LP 16.8° vs. 22.3°, P = 0.002). There were no significant differences in the postoperative CSA between groups. No significant predictors of change in pre- and postoperative CM were found. CONSLUSIONS: There were no significant pre-or postoperative differences following the 2 procedures, suggesting radiographic equipoise in well indicated patients. Across all groups, lordosis decreased, cSVA increased, and cervical mismatch increased. There were no predictive factors that led to change in cervical mismatch.

Upstream Effects: Intraoperative Migration of Intradural Extramedullary Tumor After Non-Adjacent Level Stenosis Decompression.

A 74-year-old man with back pain, foot numbness, and hip/thigh radiculopathy was found to have an L1-L2 intradural extramedullary neoplasm and severe L4-L5 stenosis. L4-L5 minimally invasive laminectomy for decompression and concomitant L1-L2 minimally invasive laminectomy for tumor resection were planned. L4-L5 laminectomy was completed first followed by the L1-L2 laminectomy. On extensive intradural exploration at L1-L2, no neoplasm was found. Immediate postoperative imaging showed that the intradural extramedullary tumor had migrated caudally by nearly a complete spinal level, presumably due to changes in cerebrospinal fluid pressure and resultant shift in intradural contents after the L4-L5 laminectomy. Successful resection of the intradural extramedullary tumor was performed, with improvement in the patient's symptoms.