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

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

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.

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.

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.

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.

The Effect of Slime Factor in the Treatment of Spinal Implant Infections.

AIM: To investigate the effect of the biofilm-forming ability of the bacteria on treatment in rats by using biofilm-forming and nonbiofilm- forming strains of Staphylococcus aureus (S. aureus). MATERIAL AND METHODS: Forty rats were divided into four equal groups as Group 1A, 1B, 2A, and 2B. All rats underwent single distance lumbar laminectomy, and titanium implants were introduced. Group 1 rats were inoculated with Slime factor (-) S. aureus, while Group 2 rats were inoculated with biofilm Slime factor (+) S. aureus. None of the rats were given antibiotics. One week later, the surgical field was reopened and microbiological samples were taken. The implants of rats in Groups 1A and 2A were left in place, while the implants of rats in Groups 1B and 2B were removed. RESULTS: There was no statistically significant difference between the groups inoculated with slime factor (+) S. aureus; although, Groups 1A and 2A showed statistically significant difference. Statistical analysis with respect to bacterial count also showed a statistically significant difference between Groups 1A and 2A. There was a statistically significant difference between Group 1B and 2B. CONCLUSION: The results obtained in the present study reveal that in case of implant-dependent infection, the first sample taken can be checked for slime factor, and if there is infection with slime factor-negative bacterium, treatment without removing the implant may be recommended. S. aureus was used in the study because it is the most common cause of implant-related infection at surgical sites. Further studies using different bacterial species are needed to reach a definitive conclusion.

Surgical management of a multilevel thoracolumbar aneurysmal bone cyst.

Aneurysmal bone cysts (ABCs) are primary bone tumours that rarely occur in the spine and generally affect one vertebral level in adolescents. Here, we present an unusual case of a multilevel thoracolumbar ABC, which presented a unique surgical challenge due to its infiltrative and destructive nature. A teenage male presented with back pain, paresthesias and a mildly spastic gait. MRI of the thoracolumbar spine revealed an expansive, multicystic mass extending from the left T12-L1 vertebral bodies into adjacent musculature. The patient underwent a two-stage surgical approach with decompression of the spinal cord and instrumentation to stabilise the vertebral column. The first stage involved posterior decompression, laminectomy and facetectomies, followed by pedicle-based instrumentation from T10 to L3. This was followed by a vertebrectomy and anterior stabilisation with an expansile cage from T11 to L2. A gross total resection was achieved with the patient maintaining full neurological function.

Efficacy of PE-PLIF with a novel ULBD approach for lumbar degeneration diseases: a large-channel endoscopic retrospective study.

PURPOSE: This study aims to assess the effectiveness of Percutaneous Endoscopic Posterior Lumbar Interbody Fusion (PE-PLIF) combined with a novel Unilateral Laminotomy for Bilateral Decompression (ULBD) approach using a large-channel endoscope in treating Lumbar Degenerative Diseases (LDD). METHODS: This retrospective analysis evaluates 41 LDD patients treated with PE-PLIF and ULBD from January 2021 to June 2023. A novel ULBD approach, called 'Non-touch Over-Top' technique, was utilized in this study. We compared preoperative and postoperative metrics such as demographic data, Visual Analogue Scale (VAS) for pain, Oswestry Disability Index (ODI), Japanese Orthopedic Association (JOA) score, surgical details, and radiographic changes. RESULTS: The average follow-up duration was 14.41 ± 2.86 months. Notable improvements were observed postoperatively in VAS scores for back and leg pain (from 5.56 ± 0.20 and 6.95 ± 0.24 to 0.20 ± 0.06 and 0.12 ± 0.05), ODI (from 58.68 ± 0.80% to 8.10 ± 0.49%), and JOA scores (from 9.37 ± 0.37 to 25.07 ± 0.38). Radiographic measurements showed significant improvements in lumbar and segmental lordosis angles, disc height, and spinal canal area. A high fusion rate (97.56% at 6 months, 100% at 12 months) and a low cage subsidence rate (2.44%) were noted. CONCLUSIONS: PE-PLIF combined with the novel ULBD technique via a large-channel endoscope offers significant short-term benefits for LDD management. The procedure effectively expands spinal canal volume, decompresses nerve structures, improves lumbar alignment, and stabilizes the spine. Notably, it improves patients' quality of life and minimizes complications, highlighting its potential as a promising LDD treatment option.

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.

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.

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.

Risk factors of instrumentation failure after laminectomy and posterior cervical fusions (PCF).

BACKGROUND: For patients with multilevel degenerative cervical myelopathy, laminectomy and posterior cervical fusions (PCF) with instrumentation are widely accepted techniques for symptom relief. However, hardware failure is not rare and results in neck pain or even permanent neurological lesions. There are no in-depth studies of hardware-related complications following laminectomy and PCF with instrumentation. METHODS: The present study was a retrospective, single centre, observational study. Patients who underwent laminectomy and PCF with instrumentation in a single institution between January 2019 and January 2021 were included. Patients were divided into hardware failure and no hardware failure group according to whether there was a hardware failure. Data, including sex, age, screw density, end vertebra (C7 or T1), cervical sagittal alignment parameters (C2-C7 cervical lordosis, C2-C7 sagittal vertical axis, T1 slope, Cervical lordosis correction), regional Hounsfield units (HU) of the screw trajectory and osteoporosis status, were collected and compared between the two groups. RESULTS: We analysed the clinical data of 56 patients in total. The mean overall follow-up duration was 20.6 months (range, 12-30 months). Patients were divided into the hardware failure group (n = 14) and no hardware failure group (n = 42). There were no significant differences in the general information (age, sex, follow-up period) of patients between the two groups. The differences in fusion rate, fixation levels, and screw density between the two groups were not statistically significant (p > 0.05). The failure rate of fixation ending at T1 was lower than that at C7 (9% vs. 36.3%) (p = 0.019). The regional HU values of the pedicle screw (PS) and lateral mass screw (LMS) in the failure group were lower than those in the no failure group (PS: 267 ± 45 vs. 368 ± 43, p = 0.001; LMS: 308 ± 53 vs. 412 ± 41, p = 0.001). The sagittal alignment parameters did not show significant differences between the two groups before surgery or at the final follow-up (p > 0.05). The hardware failure rate in patients without osteoporosis was lower than that in patients with osteoporosis (14.3% vs. 57.1%) (p = 0.001). CONCLUSIONS: Osteoporosis, fixation ending at C7, and low regional HU value of the screw trajectory were the independent risk factors of hardware failure after laminectomy and PCF. Future studies should illuminate if preventive measures targeting these factors can help reduce hardware failure and identified more risk factors, and perform long-term follow-up.

What is the Preferable Method for the C3 and C7 Segments in Unilateral Open-Door Laminoplasty for Patients Diagnosed with Cervical Spondylotic Myelopathy?

BACKGROUND: Traditional C3-C7 unilateral open-door laminoplasty (UOLP) often leads to various postoperative complications as a result of damage of cervical posterior muscles and nuchal ligaments. We aimed to thoroughly evaluate postoperative outcomes after our modified UOLP versus traditional UOLP in treating multilevel cervical spondylotic myelopathy (MCSM). METHODS: Seventy-six patients with MCSM who underwent the modified UOLP with C3 laminectomy and C7 upper hemilaminectomy (40 patients) or traditional C3-C7 UOLP (36 patients) were included. Preoperative and postoperative cervical radiologic parameters, as well as clinical and surgical outcomes, were evaluated. RESULTS: Postoperatively, Japanese Orthopaedic Association scores improved significantly more in the modified UOLP group than in the traditional UOLP group (P = 0.028), whereas visual analog scale scores and Neck Disability Index improved similarly in both groups. Follow-up scores for Japanese Orthopaedic Association, Neck Disability Index, and visual analog scale were not significantly different between the 2 groups. At the final follow-up, the C2-C7 sagittal vertical axis and T1 slope increased in the traditional UOLP group and did not change in the modified UOLP group and were unchanged in the modified UOLP group. The C2-C7 Cobb angle decreased significantly in the traditional UOLP group and did not change in the modified UOLP group. The modified UOLP group lost less cervical posterior muscle area compared with the traditional UOLP group (3.72% ± 3.54% vs. 6.67% ± 2.81%; P < 0.001). The range of motion in the modified UOLP group was significantly greater than in the traditional UOLP group at the final follow-up (P < 0.001). Also, the modified UOLP group experienced a notable reduction in operative time, blood loss volume, and postoperative hospital stay. CONCLUSIONS: We recommend performing our modified UOLP with C3 laminectomy and C7 upper hemilaminectomy instead of traditional C3-C7 UOLP.

Incidence and Risk Factors for the Development of Axial Symptoms Following Posterior Single-Door Laminoplasty: A Retrospective Analysis.

OBJECTIVE: Posterior single-door laminoplasty is a widely practiced clinical procedure, but the occurrence of postoperative axial syndrome (AS) remains a significant concern. The aim of this study was to identify risk factors associated with AS and develop a risk prediction model. METHODS: Clinical data from 226 patients who underwent posterior single-door laminoplasty between June 2017 and June 2022 were collected. Through Logistic model analysis, the risk factors of AS are clarified and the intensity of each risk factor is explained in the form of forest plot. Subsequently, we constructed a predictive model and plotted receiver operating characteristic curves to assess the model's predictive value. RESULTS: In the end, 87 cases were diagnosed with AS, resulting in an incidence rate of 38.5%. Logistic regression analysis revealed that preoperative encroachment rate of anterior spinal canal (pre-op ERASC), intraoperative facet joints destruction, intraoperative open-door angle, postoperative loss of cervical curvature, and postoperative loss of cervical range of motion were independent risk factors for AS. Conversely, preoperative cervical curvature (pre-op CC) and postoperation early function training were protective factors against AS. The Youden index indicated that the cutoff values for pre-op ERASC and pre-op CC were 26.6°and 16.5, respectively. The risk prediction model for AS was constructed and a nomogram was plotted. The model has high clinical value. CONCLUSIONS: Pre-op ERASC, pre-op CC, intraoperative facet joints destruction, intraoperative open-door angle, postoperative loss of cervical curvature, postoperative loss of cervical range of motion, and postoperation early function training are independent influencing factors for AS occurrence. The risk model has good practicability.

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.

Scapular Osteotomy for Lateral Access to a T1-2 Foraminal Disc Extrusion, Treated by Mini-Hemilaminectomy in a Dog.

A 4-year-old female spayed French bulldog was presented with a 2-day history of neck pain and left thoracic limb lameness with no neurological deficits. A computed tomography (CT) examination showed a left foraminal T1-2 disc extrusion. Surgical management was performed using a left lateral approach to the vertebral column with a scapular osteotomy. A T1-2 mini-hemilaminectomy was performed. The scapular osteotomy was stabilized with two 2.4-mm locking compression plates. The postoperative CT and radiographic examinations showed adequate decompression of the T1-2 foramen and good reduction in the scapular osteotomy. The dog was able to walk the following day. At the 1-month follow-up, the dog had no neck pain but persistent slight left thoracic limb lameness. Ten months postoperatively, a CT scan showed no abnormalities at the surgical site, and the dog had no neurological deficits nor lameness. The aim of this case report was to describe a new lateral approach to T1-2 intervertebral space.

Lumbar Spinous Process-Splitting Technique for Ligamentum Flavum Cyst Removal.

BACKGROUND: Laminotomy for lumbar stenosis is a well-defined procedure and represents a routine in every neurosurgical department. It is a common experience that the uni- or bilateral paraspinal muscle detachment, together with injury of the supra- and interspinous ligaments, can lead to postoperative pain. In the literature, the application of a minimally invasive technique, the lumbar spinous process-splitting (LSPS) technique, has been reported. METHODS: In this study, we present a case series of 12 patients who underwent LSPS from September 2019 to April 2020. Two patients had a cyst of the ligamentum flavum, eight a single-level lumbar canal stenosis (LCS), and two a two-level LCS. Moreover, we propose a novel morphological classification of postoperative muscle atrophy and present volumetric analysis of the decompression achieved. RESULTS: There were no complications related to this technique. In all patients, the vertebral canal area was more than doubled by the procedure. The muscle sparing showed grade A, according to our classification. CONCLUSION: To our knowledge, this is the first description of this surgical technique and the first LSPSL case series in Europe. Furthermore, cases of ligamentum flavum cyst removal using this safe and effective technique have not yet been reported.

Comparison of biportal endoscopic technique and uniportal endoscopic technique in Unilateral Laminectomy for Bilateral Decomprssion (ULBD) for lumbar spinal stenosis.

OBJECTIVE: Unilateral laminotomy for bilateral decompression (ULBD) has been adopted widely to treat lumbar spinal stenosis (LSS). The objective of the study is to investigate clinical and radiological outcomes of the biportal endoscopic ULBD (BE-ULBD) and uniportal endoscopic ULBD (UE-ULBD). METHODS: We collected retrospectively 65 patients' data who met the inclusion criteria (July 2019-June 2021). 33 patients underwent BE-ULBD surgery, and 32 patients underwent the UE-ULBD surgery, and were followed up for at least 1 year. The following preoperative and postoperative outcomes were compared between groups: the visual analog scale (VAS) for pain, the Oswestry disability index (ODI) for nerve function, and modified Macnab criteria for satisfaction, the cross-sectional area of the dural sac (DSCSA), the mean angle of facetectomy. RESULTS: Age, BMI, gender, levels of involvement and duration of symptoms were not significantly different at baseline in this study. Clinical data showed that postoperative ODI, VAS scores and Modified Macnab Criteria were not statistically different between the two groups. The BE-ULBD group had a shorter operation time than the UE-ULBD group (P < 0.001). Patients in the BE-ULBD group had a larger postoperative expansion of DSCSA expansion postoperatively (85.58 ± 3.16 mm2 VS 71.43 ± 3.35 mm2, P < 0.001) and a larger contralateral facetectomy angle (63.95 ± 3.34° vs 57.80 ± 3.43°, P < 0.001) compared with patients in the UE-ULBD group. There were no statistical differences in the incidence of postoperative complications between the two groups. CONCLUSION: Both the BE-ULBD and the UE-ULBD yielded clinical improvement in terms of pain and stenosis symptoms. The BE-ULBD technique has the advantages of the shorter operation time, larger DSCSA expansion and larger contralateral facetectomy angle.

Predictors of Skip Laminotomy for Placement of Paddle Leads for Spinal Cord Stimulation.

OBJECTIVES: Placement of a standard paddle lead for spinal cord stimulation (SCS) requires a laminotomy for positioning of the lead within the epidural space. During initial placement, an additional laminotomy or laminectomy, termed a "skip" laminotomy, may be necessary at a higher level to pass the lead to the appropriate midline position. Patient and radiographic factors that predict the need for a skip laminotomy have yet to be identified. MATERIALS AND METHODS: Participants who underwent SCS paddle placement at Albany Medical Center between 2016 and 2017 were identified. Operative reports were reviewed to identify the paddle type, level of initial laminotomy, target level, and skip laminotomy level. Preoperative thoracic magnetic resonance images (MRIs) were reviewed, and spinal canal diameter, interpedicular distance, and dorsal cerebral spinal fluid thickness were measured for each participant when available. RESULTS: A total of 106 participants underwent thoracic SCS placement. Of these, 97 had thoracic MRIs available for review. Thirty-eight participants required a skip laminotomy for placement of the paddle compared with 68 participants who did not. There was no significant difference in demographic features including age, sex, body mass index, and surgical history. Univariate analyses that suggested trends were selected for further analysis using binary logistic regression. Level of initial laminotomy (odds ratio [OR] = 1.51, p = 0.028), spinal canal diameter (OR = 0.71, p = 0.015), and dorsal cerebrospinal fluid thickness (OR = 0.61, p = 0.011) were correlated with skip laminotomy. Target level (OR = 1.27, p = 0.138) and time from trial (1.01, p = 0.117) suggested potential association. The multivariate regression was statistically significant, X2(10) = 28.02, p = 0.002. The model explained 38.3% of the variance (Nagelkerke R2) and predicted skip laminectomy correctly in 73.3% of cases. However, for the multivariate regression, only a decrease in spinal canal diameter (OR = 0.59, p = 0.041) was associated with a greater odds of skip laminotomy. CONCLUSIONS: This study aims to characterize the patient and radiographic factors that may predict the need to perform a skip laminotomy during the initial placement of SCS paddles. Here, we show that radiographic and anatomic variables, primarily spinal canal diameter, play an important role in predicting the need for a skip laminotomy. Furthermore, we suggest that target level for placement and level of initial laminotomy also may contribute. Further investigation of the predictive factors for performing a skip laminotomy would help optimize surgical planning and preoperative patient selection and counseling.

Multiple spinal extradural arachnoid cysts presenting as compressive myelopathy in a teenager: case report and literature review with special emphasis on postoperative spine deformity in the current minimally invasive era.

INTRODUCTION: Multiple synchronous spinal extradural arachnoid cysts are extremely rare in children and can lead to cord compression and disability. Multiple spinal extradural arachnoid cysts (SEDACs) in children with immature and growing spine need to be studied separately from multiple SEDACs in adults with mature and fully grown spine because of multiple surgical limitations in children (blood loss, surgery duration, long-term spinal stability after long segment exposure, etc.). MATERIAL AND METHODS: We planned a non-systematic literature review of similar cases described in literature to analyse the pattern of presentation, management, and outcome of this surgically curable disease. RESULTS: A total of 28 cases of paediatric multiple SEDACs in the age range of 5 months to 17 years and mean age of 11.54 years were analysed. Exposure was achieved by laminectomy in 9, laminoplastic laminotomy in 13, laminectomy in first surgery followed by laminoplasty in second surgery (re-exploration) in 1, hemilaminectomy in 2, and technique "not reported" in 3 children. Complete/near-complete recovery was seen in 27 (96.42%) children. Postoperative spine deformity was reported in 7 (25%) children and was progressive in 2 children during serial follow-up. CONCLUSIONS: Symptomatic multiple synchronous SEDACs in children is a rare surgically curable condition. Sincere attempt to find out a dural defect in all cysts is a very important step in multiple SEDAC surgery. Total cyst wall excision with closure of all dural defects is the gold standard treatment for symptomatic cases. Laminoplasty is preferred for excision of multiple SEDACs in children to prevent postoperative spine deformity during long-term follow-up. Long serial follow-up for postoperative spine deformity is necessary.