Unilateral Biportal Endoscopy for L5-S1 Extraforaminal Stenosis (Far Out Syndrome) - Technical Note with Literature Review.

Introduction: Extraforaminal stenosis in L5-S1, or far-out syndrome (FOS), is defined as L5 nerve compression by the transverse process (TP) of the L5 and the ala of the sacrum and disc bulging with/without osteophytes and/or the thickened lumbosacral and extraforaminal ligament. This study aims to describe the unilateral biportal endoscopic decompression technique of the extraforaminal stenosis at L5-S1 or far out syndrome and evaluate its clinical results with a literature review. Case Report: A 44-year-old male presented with severe right sharp shooting pain in the buttock, thigh, leg, foot, and/or toes with numbness in the foot and toes (Visual Analog Scale [VAS] 8/10) for six months with an Oswestry disability index (ODI) score of 70%. Her pain aggravated when bending forward and performing daily routine activities. He also complained of exaggeration of pain in daily regular activities. On physical examination, power in the right lower limbs was 5/5 as per the Medical Research Council (MRC) grading, and deep tendon reflexes were normal. Pre-operative X-ray and CT scan showed no instability or calcified disc osteophyte, and magnetic resonance imaging showed extraforaminal stenosis due to disc herniation at L5-S1 in Figure 1. We performed UBE-L5-S1extraforaminal discectomy surgery to resolve his symptoms. The operative time was 68 min; blood loss was 30 mL. After surgery, the patient was followed up at one week, six weeks, three months, six months, 12 months, and two years. The pain and tingling sensation in the legs improved at the 1-week follow-up, with a VAS score of 0/10 and an ODI score of 10% at the 2-year follow-up. Patient satisfaction was surveyed using Macnab's criteria at the final follow-up visit of 2 years and was found to be excellent. Post-operative imaging showed a good extraforaminal decompression at L5-S. Conclusion: Unilateral biportal endoscopy technique has brought a paradigm shift in the treatment of spinal pathologies and has served as another treatment option for the past two decades. The UBE decompression technique for extraforaminal stenosis at L5-S1 has the advantages of minimally invasive spine surgery; it is a safe and effective treatment option for treating extraforaminal stenosis at L5-S1.

Risk Factors for Unexpected Admission Following Lumbar Spine Laminectomy: A National Database Study.

Introduction Laminectomy is one of the most common orthopedic spine surgeries performed in the United States. Compared to other spine operations such as fusions, laminectomies in isolation are of lower morbidity. However, complications may arise that result in readmission to an inpatient healthcare facility. The purpose of this study is to identify the demographics and risk factors associated with unplanned 30-day readmission following a laminectomy. Methods The American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database was queried for patients who underwent a laminectomy procedure from 2015 to 2019 using CPT code 63030. This query yielded 61,708 cases. Demographic, lifestyle, comorbidity, and peri-operative factors were recorded. Independent samples Student's t-tests, chi-squared, and, where appropriate, Fisher's exact tests were used in univariate analyses to identify demographic, lifestyle, and peri-operative variables related to 30-day readmission following a laminectomy procedure. Multivariate logistic regression modeling was subsequently performed. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated and reported. Results Of the 61,708 patients included in our sample, 2,359 were readmitted within 30 days of surgery, corresponding to a readmission rate of 3.82%. Results of the univariate analysis revealed statistically significant relationships between readmission status and the following patient variables: patient age, sex, BMI, ASA classification, race, bleeding disorder, chronic obstructive pulmonary disease (COPD), diabetes, hypertension, congestive heart failure (CHF), chronic steroid use, total operative time, and tobacco use (p < 0.05). Multivariate logistic regression modeling confirmed that the following patient variables were associated with statistically significantly increased odds of readmission: age greater than 65 (p < 0.05), female sex (p = 0.013), bleeding disorder (p = 0.011), diabetes (p = 0.006), current smoker (p = 0.010), COPD (p < 0.001), steroid use (p = 0.006), ASA Class II or above (p < 0.05), and total operative time (p < 0.001). Conclusion Unplanned 30-day readmission after laminectomy is infrequent. However, increasing age, female sex, steroid use, current smokers, bleeding disorders, diabetes, COPD, CHF, a higher ASA classification, and longer operative times are independent risk factors for readmission following laminectomy.

Discrepancies in recommendations for return to regular activities after cervical spine surgery: A survey study.

Background: The recommended timing for returning to common activities after cervical spine surgery varies widely among physicians based on training background and personal opinion, without clear guidelines or consensus. The purpose of this study was to analyze spine surgeons' responses about the recommended timing for returning to common activities after different cervical spine procedures. Methods: This was a survey study including 91 spine surgeons. The participants were asked to complete an anonymous online survey. Questions regarding their recommended time for returning to regular activities (showering, driving, biking, running, swimming, sedentary work, and nonsedentary work) after anterior cervical decompression and fusion (ACDF), cervical disc replacement (CDR), posterior cervical decompression and fusion (PCDF), and laminoplasty were included. Comparisons of recommended times for return to activities after each surgical procedure were made based on surgeons' years in practice. Results: For ACDF and PCDF, there were no statistically significant differences in recommended times for return to any activity when stratified by years in practice. When considering CDR, return to non-sedentary work differed between surgeons in practice for 10 to 15 years, who recommended return at 3 months, and all other groups of surgeons, who recommended 6 weeks. Laminoplasty surgery yielded the most variability in activity recommendations, with earlier recommended return (6 weeks) to biking, non-sedentary work, and sedentary work in the most experienced surgeon group (>15 years in practice) than in all other surgeon experience groups (3 months). Conclusions: We observed significant variability in surgeon recommendations for return to regular activities after cervical spine surgery.

Action protocol of medical staff for airway obstruction after anterior cervical spine surgery: A systematic review of case reports.

BACKGROUND: Postoperative airway obstruction after anterior cervical spine surgery (ACSS) can be a fatal complication. Occasionally, it rapidly progresses to complete obstruction. There are no established standardized protocols on how medical staff should assess for signs and symptoms, seek help, or facilitate airway management after ACSS to prevent unfavorable events. This study aimed to primarily describe a systematic approach by assessing the signs and treatment outcomes of airway compromise in patients who underwent ACSS. Further, it recommended an action protocol after extubation for medical staff according to patients' symptoms to prevent unfavorable outcomes. METHODS: An extensive literature search was performed on PubMed, Web of Science, and the Cochrane Library to identify case reports, case series, and cohort studies restricted to English and published between January 1990 and March 2023. We included cases that described the signs, symptoms, and treatment of airway obstruction after ACSS. Meanwhile, cases involving complications of other known causes, cases of trauma or occipital-cervical fixation, or those using bone morphogenetic protein were excluded. RESULTS: Twenty cases from 17 studies were obtained, and their study quality was acceptable. Four patients died, and two presented with hypoxic ischemic encephalopathy. Further, five of six patients had fatal complications that initially developed within 7 h after surgery. Then, 9 (69%) of 13 patients with evidence of hematoma (69%) showed initial symptoms within 12 h after surgery. Finally, 9 of 11 patients with early-stage symptoms had favorable outcomes, and patients who developed late-stage symptoms commonly had unfavorable outcomes. CONCLUSION: The early identification of signs and symptoms and immediate treatment are important, particularly within 12 h postoperatively. We suggest a novel action protocol for medical staff according to symptom urgency, which includes the measurement of neck circumference using a string for evaluating neck swelling.

Predictors of Admission to Post-Acute Rehabilitation Following Multi-Level Spinal Decompression and Fusion Surgery and its Associated Outcomes.

OBJECTIVE: To investigate predictive factors and outcomes in those admitted to post-acute rehabilitation (PAR) versus those that discharged home following multi-level spinal decompression and fusion surgery. DESIGN: Retrospective case review study of adults that underwent multi-level spinal decompression and fusion surgery between 2016 to 2022 at an academic institution. Pre-operative, peri-operative, post-operative, and outcomes variables were compared between those discharged home versus PAR. Finally, multiple logistic regression was used to determine factors contributing to PAR admission. RESULTS: Of 241 total patients, 89 (37%) discharged home and 152 (63%) discharged to PAR. Among home discharge patients, 45.9% used an assistive device, while among PAR patients, 61.5% used one (p=0.041). Mean pre-operative Oswestry Disability Index score was significantly lower in the home discharge group compared to the PAR discharge group (40.3 vs. 45.3 respectively, p=0.044). Females were 2.43 times more likely to be discharged to PAR compared to males (95% CI: 1.06, 5.54, p=0.04). Patients with a mood disorder had 2.81 times higher odds of being discharged to PAR compared to those without (95% CI: 1.20, 6.60, p=0.02). Other variables evaluated were not statistically significant. CONCLUSIONS: Female sex and presence of a mood disorder increase the likelihood to PAR discharge following multi-level spinal decompression surgery.

Pros and Cons of Minimally Invasive Spine Surgery.

This paper reviews current knowledge on minimally invasive spine surgery (MISS). Although it has significant advantages, such as less postoperative pain, short hospital stay, quick return to work, better cosmetics, and less infection rate, there are also disadvantages. The long learning curve, the need for special instruments and types of equipment, high costs, lack of tactile sensation and biplanar imaging, some complications that are hard to treat, and more radiation to the surgeon and surgical team are the disadvantages.Most studies remark that the outcomes of MISS are similar to traditional surgery. Although patients demand it more than surgeons, we predict the broad applications of MISS will replace most of our classical surgical approaches.

A novel repair strategy using knotless squeeze anchors for lumbar disc herniation with endplate junction lesions under biportal endoscopic spinal surgery.

BACKGROUND: Annulus fibrosus-endplate (AF-EP) junction lesions are important determinants for lumbar disc herniation (LDH). Utilizing biportal endoscopic spinal surgery (BESS), we introduce a novel repair method using bioabsorbable PushLock anchors with suture fibers to stretch disconnected AF tissues to the vertebral cortex. METHODS: The viewing and working portals are established to excise herniated disc materials causing radiculopathy. Through the working portal, a suture strand is passed through the intact AF tissue near the lesion and retrieved using the Suture Crossing Device. Then, the knotless suture limbs are secured into the cortical bone socket of the vertebral body with a PushLock anchor. CONCLUSION: The procedure is a simple, safe, and feasible knotless suturing technique for the treatment of LDH with AF-EP junction lesions.

En-bloc spondylectomy in the lumbar spine: indications, results and complications in a series of 47 patients affected by primary malignant bone tumors.

INTRODUCTION: Wide Surgery is the reference treatment for malignant and aggressive benign primary bone tumors in the spine. When located in the lumbar spine, En-Bloc Spondylectomy (EBS) remains a complex challenge. Moreover, surgery is complicated by the presence of the diaphragm in the thoracolumbar junction and the hinderance of the iliac wings at the lumbosacral levels. Therefore, EBS in the lumbar spine frequently requires combined approaches. The purpose of this study is to describe clinical presentation, tumor characteristics and results of a series of 47 consecutive patients affected by malignant primary bone tumors of the lumbar spine who underwent EBS. MATERIALS AND METHODS: 47 patients were reviewed. Complications were distinguished in early and late whether they occurred before or after 30 days from surgery. Overall survival (OS), disease-free survival (DFS) and local recurrence-free survival (LRFS) were calculated by the Kaplan-Meier product-limit method from surgery until relapse or death. RESULTS: 27 patients presented to observation after a first intralesional approach in a non-specialized center. Chordoma was the most represented histotype. Vertebrectomies were: 23 one-level, 10 two-level, 12 three-level and 2 four-level. Reconstructions were always carried out with screws and rods. The main postoperative complication was blood loss, while hardware failure was the main long-term complication. The 5-year LRFS was 75.5%, the 5-year DFS was 54.3%, and 5-year OS was 63.6%. CONCLUSIONS: The surgical margin obtained during the index surgery was statistically associated with Local Recurrence, DFS and OS, underlining the importance of treating patients in reference centers.

Full endoscopic surgery for calcium pyrophosphate deposition disease (CPPD) in the cervical ligamentum flavum: report of two cervical myelopathy cases.

Calcium pyrophosphate deposition disease (CPPD), known as pseudogout, is characterized by the accumulation of calcium pyrophosphate crystals in musculoskeletal structures, primarily joints. While CPPD commonly affects various joints, involvement in the cervical spine leading to myelopathy is rare. Surgical intervention becomes necessary when conservative measures fail, but reports on full endoscopic surgeries are extremely rare. We present two successful cases where full endoscopic systems were used for CPPD removal in the cervical spine. The surgical technique involved a full endoscopic approach, adapting the previously reported technique for unilateral laminotomy bilateral decompression. Full-endoscopic removal of cervical CPPD inducing myelopathy were successfully removed with good clinical and radiologic outcomes. The scarcity of endoscopic cases for cervical ligamentum flavum CPPD is attributed to the condition's rarity. However, our successful cases advocate for endoscopic surgery as a potential primary treatment option for CPPD-induced cervical myelopathy, especially in elderly patients or those with previous cervical operation histories. This experience encourages the consideration of endoscopic surgery for managing cervical ligamentum flavum CPPD as a viable alternative.

Full endoscopic resection of ventral thoracic osteophyte and repair of spontaneous CSF leak.

Spontaneous CSF leaks frequently cause headaches, meningismus, and nausea due to intracranial hypotension. When conservative treatment fails, surgical repair is indicated. Especially ventral leaks necessitate invasive approaches with substantial blood loss and tissue trauma. Full endoscopic spine surgery (FESS) enables circumferential access via the transforaminal approach. Here, the authors show the successful repair of a ventral CSF leak in the thoracic spine after removal of bony osteophytes utilizing FESS with placement of a dural substitute and sealant. Lasting symptom relief was reported. These results suggest that FESS is safe and efficient for the repair of spontaneous and incidental CSF leaks. The video can be found here: https://stream.cadmore.media/r10.3171/2024.1.FOCVID23209.

Single position, prone oblique lateral interbody fusion (OLIF)-case illustration and technical considerations.

Oblique lateral interbody fusion (OLIF) is a powerful method to treat various spinal conditions and is frequently combined with posterior instrumentation. This is traditionally performed in dual positions, with the patient first in lateral then turned prone. Single position lateral surgery (SPS-L) has been studied in a bid to improve surgical efficiency and reduce operative costs, but various limitations have been identified. More recently, the single position prone surgery (SPS-P) has been described as an alternative to address some of these limitations. This case illustrates a patient who underwent SPS-P using an OLIF corridor with subsequent posterior decompression and instrumentation. The benefits and limitations of this procedure compared to the conventional techniques are highlighted in this case. We present the case of a 75-year-old female presenting with thoracic myelopathy over T11/12 and concurrent L2-4 spinal stenosis. She underwent OLIF of L2/3 and L3/4, posterior decompression of T11/12 and L2/3, and posterior instrumented fusion from T10-L4 via a single prone position. We aim to describe the advantages of this approach and the challenges encountered through our experience. SPS-P offers numerous benefits compared to the already powerful SPS-L. In the upper levels of the lumbar spine, a pre-psoas approach may also be feasible. However, the prone lateral technique does not replace all patients suited for a lateral interbody fusion but should be seen as a viable option for selected cases such as those with previous fusion at the L5/S1 with adjacent degeneration requiring extension and posterior fixation.

Expandable cages that expand both height and lordosis provide improved immediate effect on sagittal alignment and short-term clinical outcomes following minimally invasive transforaminal lumbar interbody fusion (MIS TLIF).

Background: Failure to restore lordotic alignment is not an uncommon problem following minimally invasive transforaminal lumbar interbody fusion (MIS TLIF), even with expandable cages that increase disc height. This study aims to investigate the effect of the expandable cage that is specifically designed to expand both height and lordosis. We evaluated the outcomes of MIS TLIF in restoring immediate postoperative sagittal alignment by comparing two different types of expandable cages. One cage is designed to solely increase disc height (Group H), while the other can expand both height and lordosis (Group HL). Methods: Patients undergoing MIS TLIF using expandable cages were retrospectively reviewed, including 40 cases in Group H and 109 cases in Group HL. Visual analog scores of back and leg pain, and Oswestry disability index were collected. Disc height, disc angle, and sagittal alignment were measured. Complications were recorded, including early subsidence which was evaluated with computed tomography. Results: Clinical and radiographic outcomes significantly improved in both groups postoperatively. Group HL showed superior improvement in segmental lordosis (4.4°±3.5° vs. 2.1°±4.8°, P=0.01) and disc angle (6.3°±3.8 vs. 2.2°±4.3°, P<0.001) compared to Group H. Overall incidence of early subsidence was 23.3%, predominantly observed during initial cases as part of the learning curve, but decreased to 18% after completion of the first 20 cases. Conclusions: Expandable cages with a design specifically aimed at increasing lordotic angle can provide favorable outcomes and effectively improve immediate sagittal alignment following MIS TLIF, compared to conventional cages that only increase in height. However, regardless of the type of expandable cage used, it is crucial to avoid applying excessive force to achieve greater disc height or lordosis, as this may contribute to subsidence and a possible reduction in lordotic alignment restoration. Long-term results are needed to evaluate the clinical outcome, fusion rate, and maintenance of the sagittal alignment.

Enhanced recovery after elective spinal surgery: an Australian pilot study.

Background: The principles of enhanced recovery after surgery (ERAS) aim to reduce the physiological stress of surgery which in turn improve clinical and health economic outcomes. There is ample evidence in literature supporting ERAS methodologies in other surgical specialties, but its adoption in spinal surgery, especially in Australia remains in infancy. The aim of this project is to describe the early experience with an evidence-based ERAS pathway for simple spine surgery, a first of its kind in Australia. Methods: An ERAS protocol was designed using an evidenced-based review of the literature. The authors then conducted a prospective cohort analysis looking at outcome of patients undergoing elective spinal (lumbar and cervical) decompression surgery under ERAS principles by a single surgeon on the Westmead Hospital Campus between March 2021 to May 2023. Primary outcomes were patient length of stay (LOS), patient reported pain and disability scores and complications (including readmissions within 30 days and re-operation within 6 months). Secondary outcomes included predictors of failure for same-day discharge. Results: A total of 52 patients underwent spinal decompression surgeries under the ERAS protocol. Overall 43 out of 52 patients (83.7%) were successfully discharged on the same day as their surgery. Patient reported outcomes were improved at 6 weeks and 6 months confirming durability of intervention. The rates of complications were similar to literature reported rates for simple lumbar or cervical decompression procedures and there were no readmissions within 30 days or re-operations within 6 months of surgery. Being of non-English speaking background [odds ratio (OR) =6.08, P=0.04] and from home alone (OR =10.25, P=0.03) were predictors of failure of same day discharge in this small cohort. Conclusions: Implementation of ERAS protocols for simple spinal decompression surgeries is feasible and produces durable improved patient outcomes while reducing LOS in hospitals. Patient social factors can be predictive of lack of compliance.

Postoperative Airway Management after Anterior Cervical Spine Surgery: Retrospective Neurosurgical Multicenter Study.

Airway complications that occur after anterior cervical spine surgery pose a life-threatening risk, which encompasses complications including prolonged intubation, unplanned reintubation, and/or necessity of tracheostomy. The present study aimed to identify the surgical risks associated with postoperative airway complications in neurosurgical training institutes. A retrospective, multicenter, observational review of data from 365 patients, who underwent anterior cervical spine surgery between 2018 and 2022, at three such institutes was carried out. Postoperative airway complication was defined as either the need for prolonged intubation on the day of surgery or the need for unplanned reintubation. The perioperative medical information was obtained from their medical records. The average age of the cohort was over 60 years, with males comprising approximately 70%. Almost all surgeries predominantly involved anterior cervical discectomy and fusion or anterior cervical corpectomy and fusion, with most surgeries occurring at the level of C5/6. In total, 363 of 365 patients (99.5%) were extubated immediately after surgery, and the remaining two patients were kept under intubation because of the risk of airway complications. Of the 363 patients who underwent extubation immediately after surgery, two (0.55%) required reintubation because of postoperative airway complications. Patients who experienced airway complications were notably older and exhibited a significantly lower body mass index. The results of this study suggested that older and frailer individuals are at an elevated risk for postoperative airway complications, with immediate postoperative extubation generally being safe but requiring careful judgment in specific cases.

Intensive Care Unit Admission After Spine Surgery: A Narrative Review.

INTRODUCTION: Intensive care unit (ICU) admissions constitute a substantial financial challenge for health care systems and patients and are linked to various potentially life-altering complications. A wide range of patient-related, surgical, and medical factors are associated with an increased risk of ICU admission following spine surgery. DISCUSSION: The most notable examples include lung, heart, and kidney disease, as well as estimated blood loss and length of surgery. Various scores that include the most significant patient- and procedure-related factors have been described to assess the risk associated with surgery for individual patients. To date, the fusion risk score and the American Society of Anesthesiologists score have been the most useful in predicting postoperative complications and admission to the ICU. However, other risk factors have also been implicated in ICU admission and length of stay. The current scores must further adapt by using the available evidence to fulfill their intended purpose. Moreover, a handful of measures have shown efficacy in decreasing ICU admission and length of stay, with their benefits still to be demonstrated by future research. CONCLUSION: This review underscores the risk factors predictive of ICU admission following spine surgery and will help surgeons and clinicians in patient stratification. However, future studies are needed to validate the role of protective measures in preventing ICU admissions and the significance of certain risk factors.

Unexpected positive culture (UPC) in adults revision spine surgery: a systematic review and meta-analysis of incidence, risk factors, and management.

BACKGROUND: Without clear signs of infection, spinal implant failure is attributed to mechanical overloads and aseptic loosening. However, how low-grade infections contribute to seemingly aseptic implant failure is unclear. PURPOSE: The systematic review examined unexpected positive cultures (UPCs) in revision spine surgery regarding prevalence, isolated pathogens, risk factors, and strategies to reduce infection among asymptomatic patients undergoing revision spine surgery. METHODS: We followed the PRISMA guidelines and searched four main databases (PubMed, EMBASE, SCOPUS, Web of Science) comprehensively until January 2023 for articles reporting UPC after presumed aseptic adult revision spine surgery. The UPC rates were pooled, and risk factors were compared with the culture-negative control group and represented as odds ratio (OR) or mean difference (MD). RESULTS: Fifteen studies of 1057 individuals were included in two groups: culture-positive or UPCs (n = 317) and culture-negative or control (n = 740). The overall UPC prevalence was 33.2% (317/1057, range: 0 to 53%, 95% CI = 30.2%-36.4%), and Cutibacterium acnes (43.0%, 95% CI = 37.4%-48.8%), Coagulase-negative Staphylococci (CoNS), (39.5%, 95% CI = 33.2%-46.2%), and Staphylococcus species in general (49.5%, 95%CI = 43.7%-55.4%) were reported the most common isolated microbes. 16.1% of the UPCs were polymicrobial. Risk factors associated with UPC rates were female sex (OR = 2.62, 95%CI = 1.76-3.90, P < 0.001), screw loosening (OR = 4.43, 95%CI = 1.31-15.02, P = 0.02), number of operated levels (MD = 0.77, 95%CI = 0.33-1.22, P = 0.0007), and shorter time since index surgery (MD = - 8.57 months, 95%CI = - 14.76, -2.39, P = 0.02). CONCLUSIONS: One-third of patients undergoing spine revision surgery revealed UPC in this study. Each UPC pathogen interpretation and antibiotic use decision should be interpreted case by case. LEVEL OF EVIDENCE: IV.

Intraoperative Cone-Beam Computed Tomography Navigation Versus 2-Dimensional Fluoroscopy in Single-Level Lumbar Spinal Fusion: A Comparative Analysis.

OBJECTIVE: Several studies have advocated for the higher accuracy of transpedicular screw placement under cone-beam computed tomography (CBCT) compared to conventional 2-dimensional (2D) fluoroscopy. The superiority of navigation systems in perioperative and postoperative outcomes remains a topic of debate. This study aimed to compare operative time, screw placement time and accuracy, total radiation dose, perioperative and postoperative outcomes in patients who underwent transpedicular screw fixation for degenerative lumbar spondylolisthesis (DLS) using intraoperative CBCT navigation versus 2D fluoroscopy. METHODS: A retrospective analysis was conducted on patients affected by single-level DLS who underwent posterior lumbar instrumentation with transpedicular screw fixation using surgical CBCT navigation (NV group) or 2D fluoroscopy-assisted freehand technique (FH group). Demographics, screw placement time and accuracy, operative time, total radiation dose, intraoperative blood loss, screw revision rate, complications, and length of stay (LOS) were assessed. RESULTS: The study included a total of 30 patients (NV group: n = 15; FH group: n = 15). The mean screw placement time, operative time, and LOS were significantly reduced in the NV group compared to the FH group (p < 0.05). The total radiation dose was significantly higher in the NV group (p < 0.0001). No significant difference was found in terms of blood loss and postoperative complications. CONCLUSION: This study suggests that intraoperative CBCT-navigated single-level lumbar transpedicular screw fixation is superior in terms of mean screw placement time, operative time, and LOS compared to 2D fluoroscopy, despite a higher intraoperative radiation exposure.

Robotic-Assisted Spine Surgery: Role in Training the Next Generation of Spine Surgeons.

OBJECTIVE: This study aimed to assess the degree of interest in robot-assisted spine surgery (RASS) among residents and to investigate the learning curve for beginners performing robotic surgery. METHODS: We conducted a survey to assess awareness and interest in RASS among young neurosurgery residents. Subsequently, we offered a hands-on training program using a dummy to educate one resident. After completing the program, the trained resident performed spinal fusion surgery with robotic assistance under the supervision of a mentor. The clinical outcomes and learning curve associated with robotic surgery were then analyzed. RESULTS: Neurosurgical residents had limited opportunities to participate in spinal surgery during their training. Despite this, there was a significant interest in the emerging field of robotic surgery. A trained resident performed RASS under the supervision of a senior surgeon. A total of 166 screw insertions were attempted in 28 patients, with 2 screws failing due to skiving. According to the Gertzbein-Robbins classification, 85.54% of the screws were rated as grade A, 11.58% as grade B, 0.6% as grade C, and 1.2% as grade D. The clinical acceptance rate was approximately 96.99%, which is comparable to the results reported by senior experts and time per screw statistically significantly decreased as experience was gained. CONCLUSION: RASS can be performed with high accuracy within a relatively short timeframe, if residents receive adequate training.

A Propensity Score-Matched Cohort Study Comparing 3 Different Spine Pedicle Screw Fixation Methods: Freehand, Fluoroscopy-Guided, and Robot-Assisted Techniques.

OBJECTIVE: This study aimed to compare the accuracy of robotic spine surgery and conventional pedicle screw fixation in lumbar degenerative disease. We evaluated clinical and radiological outcomes to demonstrate the noninferiority of robotic surgery. METHODS: This study employed propensity score matching and included 3 groups: robot-assisted mini-open posterior lumbar interbody fusion (PLIF) (robotic surgery, RS), c-arm guided minimally invasive surgery transforaminal lumbar interbody fusion (C-arm guidance, CG), and freehand open PLIF (free of guidance, FG) (54 patients each). The mean follow-up period was 2.2 years. The preoperative spine condition was considered. Accuracy was evaluated using the Gertzbein-Robbins scale (GRS score) and Babu classification (Babu score). Radiological outcomes included adjacent segmental disease (ASD) and mechanical failure. Clinical outcomes were assessed based on the visual analogue scale, Oswestry Disability Index, 36-item Short Form health survey, and clinical ASD rate. RESULTS: Accuracy was higher in the RS group (p < 0.01) than in other groups. The GRS score was lower in the CG group, whereas the Babu score was lower in the FG group compared with the RS group. No significant differences were observed in radiological and clinical outcomes among the 3 groups. Regression analysis identified preoperative facet degeneration, GRS and Babu scores as significant variables for radiological and clinical ASD. Mechanical failure was influenced by the GRS score and patients' age. CONCLUSION: This study showed the superior accuracy of robotic spine surgery compared with conventional techniques. When combined with minimally invasive surgery, robotic surgery is advantageous with reduced ligament and muscle damage associated with traditional open procedures.

Advancements and Challenges in Robot-Assisted Bone Processing in Neurosurgical Procedures.

OBJECTIVE: Practical applications of nerve decompression using neurosurgical robots remain unexplored. Our ongoing research and development initiatives, utilizing industrial robots, aim to establish a secure and efficient neurosurgical robotic system. The principal objective of this study was to automate bone grinding, which is a pivotal component of neurosurgical procedures. METHODS: To achieve this goal, we integrated an endoscope system into a manipulator and conducted precision bone machining using a neurosurgical drill, recording the grinding resistance values across 3 axes. Our study encompassed 2 core tasks: linear grinding, such as laminectomy, and cylindrical grinding, such as foraminotomy, with each task yielding unique measurement data. RESULTS: In linear grinding, we observed a proportional increase in grinding resistance values in the machining direction with acceleration. This observation suggests that 3-axis resistance measurements are a valuable tool for gauging and predicting deep cortical penetration. However, problems occurred in cylindrical grinding, and a significant error of 10% was detected. The analysis revealed that multiple factors, including the tool tip efficiency, machining speed, teaching methods, and deflection in the robot arm and jig joints, contributed to this error. CONCLUSION: We successfully measured the resistance exerted on the tool tip during bone machining with a robotic arm across 3 axes. The resistance ranged from 3 to 8 Nm, with the measurement conducted at a processing speed approximately twice that of manual surgery performed by a surgeon. During the simulation of foraminotomy under endoscopic grinding conditions, we encountered a -10% error margin.