Utilization of robotic pars repair for early return to activity in adolescents with symptomatic spondylolysis

J Neurosurg Spine 44:349–354, 2026

This case series from a tertiary academic spine center reports outcomes of robot-assisted percutaneous pars repair in nine adolescents with symptomatic lumbar spondylolysis who failed conservative management. The authors describe a single–midline incision technique using CT-based robotic guidance and a single lagged transdefect screw, detailing operative workflow, implant sizes, and a standardized postoperative rehabilitation protocol.

Results show most patients returned to preinjury or higher activity within months, with low complication rates and radiographic evidence of union in those who obtained CT follow-up. The authors conclude that minimally invasive robotic pars repair is a viable option after failed nonoperative care and advocate timely surgical consultation to potentially accelerate return to sport and avoid progressive spondylolisthesis.

Clinical problem Symptomatic lumbar pars interarticularis fractures (spondylolysis) are a common cause of adolescent low-back pain; nonoperative care with activity modification is standard first-line treatment.

Nonunion risk Despite conservative management, about 20% of patients may progress to symptomatic nonunion, and some can later develop spondylolisthesis that may require fusion.

Study aim Robotic surgical guidance was used to enable percutaneous pars screw placement; the series reports the largest cohort of adolescents treated with robot-assisted pars repair to date.

Design & cohort Retrospective review of a prospectively collected database identified 9 adolescents/young adults (13–25 years) treated with a single-screw pars repair technique.

Technique Using Excelsius robotic planning/registration and intraoperative 3D imaging, bilateral screw trajectories were planned to converge so bilateral pars screws could be placed through a single 1–2 cm midline incision; compression was achieved via a “lag-by-technique” preparation without direct pars visualization/grafting.

Postop protocol Patients walked only for 2 weeks, then added stationary biking for 2 weeks, followed by 4 weeks of sport-directed physical therapy; if tolerated symptom-free, they were cleared for activity (cleared to begin return-to-sport training at 4 weeks).

Outcomes Mean preop activity cessation at consultation was 8.6 ± 10.6 months; at mean follow-up 11.4 ± 9.1 months, 78% had returned to baseline activity or were cleared to return to sport.

Safety/efficacy conclusion Robot-assisted pars repair was reported as a safe, effective option after failed nonoperative care, enabling return to activity in as little as 8 weeks; a single lag-style screw may be clinically effective compared with prior open debridement/bone-grafting approaches.

Minimally invasive surgical evacuation confers a mortality benefit in patients with moderate-sized putaminal hemorrhages

J Neurosurg 143:1514–1521, 2025

Minimally invasive surgical (MIS) evacuation of moderate-sized putaminal intracerebral hemorrhages (pICH, 10–50 mL) was retrospectively compared with matched maximal medical management in a single-center cohort. The study found similar utility-weighted functional outcomes but a marked reduction in 1-year mortality (3% surgical vs 24% medical) and shorter ICU length of stay for surgically treated patients, with an incremental cost-effectiveness ratio of ~$68,463 per QALY.

Detailed stereotactic volumetric mapping revealed that hemorrhage spatial distribution predicts outcome differently by treatment: anteromedial extension (caudate/anterior limb internal capsule) associated with worse surgical outcomes, while posterior/superior extension (corona radiata/frontal lobe) predicted worse medical outcomes. The authors propose imaging-based selection criteria for MIS candidacy and recommend validation in larger, multicenter studies.

• Mortality Benefit: Minimally invasive surgical (MIS) evacuation of moderate-sized putaminal intracerebral hemorrhages (pICHs, 10–50 mL) significantly reduced 1-year mortality compared to medical management (3% vs 24%, p = 0.010).

• Functional Outcome: Functional outcomes (utility-weighted modified Rankin Scale) were statistically similar between surgical and medical cohorts, with no significant difference detected (mean uw-mRS 0.44 vs 0.33, p = 0.174), possibly due to limited sample size.

• ICU Stay: MIS evacuation resulted in a shorter median ICU length of stay by 3 days compared to medical management (4 vs 7 days, p = 0.045).

• Cost-Effectiveness: Surgical evacuation was cost-effective with an incremental cost-effectiveness ratio of $68,462.55 per quality-adjusted life year (QALY), under the commonly accepted $100,000/QALY threshold.

• Anatomical Predictors: Poor functional outcomes after MIS were associated with anteromedial hemorrhage extension (anterior limb of internal capsule/caudate), while poor outcomes after medical management were linked to posterior/superior extension (frontal lobe/corona radiata).

• Patient Selection: Imaging-based spatial distribution of pICH can help predict which patients may benefit most from surgical versus medical management, suggesting a role for CT-based anatomical biomarkers in clinical decision-making.

• Study Limitations: Retrospective, single-center design, small sample size, and potential selection bias limit generalizability and statistical power, especially regarding functional outcome differences.

• Guideline Context: Current evidence and guidelines do not define optimal selection criteria for surgery in basal ganglia ICH, highlighting the need for further prospective, multicenter research to refine indications for MIS evacuation

Minimally invasive surgical decompression for lumbosacral extraforaminal stenosis (Far-Out Syndrome)

Acta Neurochirurgica (2025) 167:139

The document discusses a minimally invasive surgical technique for decompressing lumbosacral extraforaminal stenosis, known as “far-out syndrome,” focusing on the L5 nerve root. It highlights the procedure, indications, potential complications, and the importance of specific imaging techniques for accurate diagnosis and effective treatment.

• The study focuses on minimally invasive surgical decompression for lumbosacral extraforaminal stenosis, known as “far-out syndrome”.

Accurate diagnosis is challenging due to unique anatomical characteristics, requiring oblique coronal MR imaging for detection.

• The procedure involves a paraspinal approach using a tubular retractor to decompress the L5 nerve root.

Adequate decompression requires the resection of the L5 lower vertebral body bony spur, transverse process, and sacral ala.

Key surgical landmarks include the transverse process, sacral ala, and superior articular process, which are drilled to relieve nerve compression.

Common symptoms include unilateral leg pain, weakness, and neurogenic claudication, often presenting unilaterally.

Surgical indications involve unilateral radiating leg pain resistant to conservative management and MRI evidence of extraforaminal compression.

Complications can be avoided by ensuring adequate decompression and removing ventral bony spurs.

Feasibility of Robotic Transorbital Surgery

Operative Neurosurgery 28:506–510, 2025

This study explores the feasibility of robotic-assisted lateral transorbital surgery for accessing Meckel cave. Challenges include tool size and limited entry space, though internal surgical space is adequate. Future advancements in smaller, haptic-enabled tools could enhance the practicality of this approach.

• The study explores the feasibility of robotic-assisted lateral transorbital approach (LTOA) using the DaVinci Xi model for neurosurgery.

Six cadaver heads were used for dissection to evaluate tool insertion and movement.

• The current robotic tools are too large for effective LTOA, limiting the insertion to one tool and a camera.

• Removing the lateral orbital rim (LOR) provides more space but still limits tool usage due to size constraints.

• There is potential for LTOA with smaller, more precise tools in the future, offering a wide surgical field around Meckel cave.

• The study highlights the need for development of narrower robotic instruments and haptic feedback systems for better surgical outcomes.

• Multiportal techniques, like adding a transnasal portal, could enhance tool use, but haptic feedback remains a critical need.

Prone Lateral Transpsoas Approach to the Spine: A Technical Guide for Mastery

Int J Spine Surg 2025, 19 (S1) S19-S27

• The prone lateral transpsoas (PTP) approach offers an alternative to traditional lateral lumbar interbody fusion (LLIF), allowing direct posterior access without repositioning the patient.

Advantages of PTP include improved segmental lordosis, single-position surgery, and ease of posterior techniques, though it has a distinct learning curve.

• The technical guide aims to shorten the learning curve, optimize surgical workflow, and ensure patient safety through preoperative planning and technical adjustments.

Preoperative imaging is crucial for assessing anatomical characteristics and guiding surgical approach decisions.

Patient positioning in PTP involves prone positioning on a radiolucent table, with special attention to stabilizing the pelvis and optimizing working angles.

Intraoperative monitoring with triggered electromyography (t-EMG) is essential to minimize lumbar plexus injury risk.

Technical pearls include strategies for retractor positioning, minimizing retraction time, and using intraoperative navigation to enhance safety and efficiency.

Conclusion: PTP LIF is a viable alternative to traditional methods, offering significant benefits but requiring mastery of its unique technical nuances.

MRI‑guided laser interstitial thermal therapy in epilepsy: indications, technique and outcome in an adult population. A single‑center data analysis

Acta Neurochirurgica (2025) 167:39

• MRI-guided Laser Interstitial Thermal Therapy (MRIgLITT) is explored as a treatment for drug-resistant epilepsy (DRE), offering a minimally invasive alternative to open surgery.

• The study conducted a retrospective analysis of 32 MRIgLITT procedures at a single center, focusing on seizure control and cognitive outcomes.

• Patient Demographics: 28 patients with various pathologies, including hippocampal sclerosis (HS), hypothalamic hamartoma (HH), and focal cortical dysplasia (FCD).

• Outcomes: High rates of seizure freedom were observed, particularly in HS and HH patients, with Engel I outcomes achieved in a significant portion.

• Cognitive Changes: 71.44% of patients showed cognitive stability or improvement one year after the procedure.

• Advantages of MRIgLITT: Offers quicker recovery, better cognitive preservation, and is effective for deep or complex epileptic foci.

• Challenges: The relationship between clinical factors and outcomes remains unclear, necessitating further large-scale studies.

• Methodology: The procedure involves precise trajectory planning and real-time MRI monitoring to ensure accurate ablation with minimal impact on surrounding tissues.

Endoscopic Versus Traditional Thoracic Discectomy: A Multicenter Retrospective Case Series and Meta-Analysis

Neurosurgery 96:152–171, 2025

Surgical treatment for symptomatic thoracic disc herniations (TDH) involves invasive open surgical approaches with relatively high complication rates and prolonged hospital stays. Although advantages of full endoscopic spine surgery (FESS) are well-established in lumbar disc herniations, data are limited for the endoscopic treatment of TDH despite potential benefits regarding surgical invasiveness. The aim of this study was to provide a comprehensive evaluation of potential benefits of FESS for the treatment of TDH.

METHODS: PubMed, MEDLINE, EMBASE, and Scopus were systematically searched for the term “thoracic disc herniation” up to March 2023 and study quality appraised with a subsequent meta-analysis. Primary outcomes were perioperative complications, need for instrumentation, and reoperations. Simultaneously, we performed a multicenter retrospective evaluation of outcomes in patients undergoing full endoscopic thoracic discectomy.

RESULTS: We identified 3190 patients from 108 studies for the traditional thoracic discectomy meta-analysis. Pooled incidence rates of complications were 25% (95% CI 0.22-0.29) for perioperative complications and 7% (95% CI 0.05-0.09) for reoperation. In this cohort, 37% (95% CI 0.26-0.49) of patients underwent instrumentation. The pooled mean for estimated blood loss for traditional approaches was 570 mL (95% CI 477.3-664.1) and 7.0 days (95% CI 5.91-8.14) for length of stay. For FESS, 41 patients from multiple institutions were retrospectively reviewed, perioperative complications were reported in 4 patients (9.7%), 4 (9.7%) required revision surgery, and 6 (14.6%) required instrumentation. Median blood loss was 5 mL (IQR 5-10), and length of stay was 0.43 days (IQR 0-1.23).

CONCLUSION: The results suggest that full endoscopic thoracic discectomy is a safe and effective treatment option for patients with symptomatic TDH. When compared with open surgical approaches, FESS dramatically diminishes invasiveness, the rate of complications, and need for prolonged hospitalizations. Full endoscopic spine surgery has the capacity to alter the standard of care for TDH treatment toward an elective outpatient surgery.

Staged Versus Same-Day Surgery in Circumferential Minimally Invasive Deformity Correction

Neurosurgery 95:1040–1045, 2024

We sought to compare long-term clinical and radiographic outcomes in patients who underwent staged vs same-day circumferential minimally invasive surgery (cMIS) for adult spinal deformity (ASD).

METHODS: We reviewed staged and same-day cMIS ASD cases in a prospective multi-institution database to compare preoperative and 2-year clinical and radiographic parameters between cohorts.

RESULTS: A total of 85 patients with a 2-year follow-up were identified (27 staged, 58 same-day). Staged patients had more extensive surgeries and greater hospital length of stay (all P < .001). There were no significant differences in preoperative or 2-year postoperative clinical metrics between cohorts. Patients in the staged cohort also had greater preoperative coronal deformity and thus experienced greater reduction in coronal deformity at 2 years (all P < .01).

CONCLUSION: Patients undergoing staged or same-day cMIS correction had similar outcomes at 2 years postoperatively. Staged cMIS ASD correction may be more appropriate in patients with greater deformity, higher frailty, and who require longer, more extensive surgeries.

A Novel Method for Angioscopic Imaging and Visualizing the Skull Base Using Complementary Metal Oxide Semiconductor Cameras

Neurosurgery 93:1432–1436, 2023

Complementary metal oxide semiconductor (CMOS) electrode arrays are a novel technology for miniaturized endoscopes; however, its use for neurointervention is yet to be investigated. In this proof-of-concept study, we aimed to demonstrate the feasibility of CMOS endoscopes in a canine model by providing direct visualization of the endothelial surface, deploying stents and coils, and accessing the spinal subdural space and skull base.

METHODS: Using 3 canine models, standard guide catheters were introduced into the internal carotid and vertebral arteries through the transfemoral route using fluoroscopy. A 1.2-mm CMOS camera was delivered through the guide catheter to inspect the endothelium. Next, the camera was introduced alongside standard neuroendovascular devices including coils and stents to provide direct visualization of their deployment within the endothelium during fluoroscopy. One canine was used for skull base and extravascular visualization. A lumbar laminectomy was performed, and the camera was navigated within the spinal subdural space until the posterior circulation intracranial vasculature was visualized.

RESULTS: We successfully visualized the endothelial surface and performed several endovascular procedures such as deployment of coils and stents under direct endovascular, angioscopic vision. We also demonstrated a proof of concept for accessing the skull base and posterior cerebral vasculature using CMOS cameras through the spinal subdural space.

CONCLUSION: This proof-of-concept study demonstrates the feasibility of CMOS camera technology to directly visualize endothelium, perform common neuroendovascular procedures, and access the base of the skull in a canine model.

Minimally Invasive Hematoma Evacuation Using the MindsEye Expandable Tubular Retractor

World Neurosurg. (2023) 176:162-167

Recent advances in intraoperative neuronavigation and cranial access devices have facilitated an increasing interest in the use of minimally invasive techniques (minimally invasive surgery) to safely treat
subcortical lesions via a parafascicular approach.

Newly developed expandable retractors, such as the MindsEye system further optimize such approaches. In this technical report, we describe the nuances in minimally invasive surgery parenchymal hematoma evacuation using the MindsEye device.

METHODS: After placement of the device, the inner stylet and inner obturator are removed, and the expandable sheath is left in place and secured into place with a Greenberg refractor. The sheath easily dilates to the surgeon’s preference with a dial, and the walls of the sheath
are composed of a thin, clear, membrane to allow easy visualization of the lesion. We additionally retrospectively reviewed clinical characteristics and outcomes across three patients treated at our facility with spontaneous multicompartment intracranial hematoma using the Mind-sEye system.

RESULTS: We provide a video case demonstrating the use of the MindsEye retractor in a transfrontal parenchymal hematoma evacuation. Successful evacuation with achieved in less than 90 minutes with near total clot removal and resolution of mass effect for all reviewed cases with no patients experiencing procedure-related postoperative decline.

CONCLUSIONS: Minimally invasive catheter-based and parafascicular approaches using tubular retractors are increasingly recognized as a viable option in the treatment of subcortical lesions. The MindsEye is the first expandable brain access port designed for removal of deep
intracranial lesions. We believe it represents a recent addition in the armament of cranial surgeons.

Minimally invasive image‑guided endoscopic evacuation of intracerebral haemorrhage

Acta Neurochirurgica (2023) 165:1597–1602

Minimally invasive endoscopic hematoma evacuation (MEHE) is an emerging surgical technique for treating spontaneous supratentorial intracerebral haemorrhage (SSICH). Multiple studies, analysing whether the outcome after such a procedure is improved, are still ongoing.

Method We herein present the indications, advantages, and perioperative considerations for the surgical technique of MEHE applied at our institution.

Conclusion MEHE with a view through a transparent brain access device is a valid and safe approach for the surgical evacuation of SSICH.

Minimally invasive modification of the Goel-Harms atlantoaxial fusion technique

Neurosurg Focus 54(3):E14, 2023

The Goel-Harms atlantoaxial screw fixation technique for the treatment of atlantoaxial instability and unstable odontoid fractures is reliable and reproducible for a variety of anatomies. The drawbacks of the technique are the potential for significant bleeding from the C2 nerve root venous plexus and the risks associated with posterior midline exposure and retraction, such as pain and wound complications. The authors developed a minimally invasive surgical (MIS) modification of the Goel-Harms technique using intra-articular grafting to facilitate placement of percutaneous lateral mass and pars screws with extended tabs for minimally invasive subfascial rod placement. The objective of this study was to present the authors’ first series of 5 patients undergoing minimally invasive modification in comparison with 51 patients undergoing open atlantoaxial fusion.

METHODS A retrospective analysis of patient comorbid conditions, blood loss, length of surgery, and length of stay was performed on patients undergoing Goel-Harms instrumented fusion (GHIF) for unstable odontoid fractures performed between 2016 and 2021.

RESULTS Patients undergoing the minimally invasive procedure showed significantly less blood loss than those undergoing the open atlantoaxial fusion procedure, with a median blood loss of 30 ml compared with 150 ml using the open technique (p < 0.01). The patients showed no significant differences in length of stay (2 days for MIS vs 4 days for open atlantoaxial fusion, p = 0.25). There were no significant differences in length of surgery for MIS, but a possible trend toward increased operative duration (234 vs 151 minutes, p = 0.112).

CONCLUSIONS In this small pilot study, it was shown that MIS-GHIF can be performed with decreased blood loss in atlantoaxial instability and odontoid fractures. This technique may allow for greater and safer application of the procedure in the elderly and infirm.

 

Minimally invasive surgery for spinal cerebrospinal fluid leaks in spontaneous intracranial hypotension

J Neurosurg Spine 38:147–152, 2023

Spinal CSF leaks cause spontaneous intracranial hypotension (SIH). Surgical closure of spinal CSF leaks is the treatment of choice for persisting leaks. Surgical approaches vary, and there are no studies in which minimally invasive techniques were used. In this study, the authors aimed to detail the safety and feasibility of minimally invasive microsurgical sealing of spinal CSF leaks using nonexpandable tubular retractors.

METHODS Consecutive patients with SIH and a confirmed spinal CSF leak treated at a single institution between April 2019 and December 2020 were included in the study. Surgery was performed via a dorsal 2.5-cm skin incision using nonexpandable tubular retractors and a tailored interlaminar fenestration and, if needed, a transdural approach. The primary outcome was successful sealing of the dura, and the secondary outcome was the occurrence of complications.

RESULTS Fifty-eight patients, 65.5% of whom were female (median age 46 years [IQR 36–55 years]), with 38 ventral leaks, 17 lateral leaks, and 2 CSF venous fistulas were included. In 56 (96.6%) patients, the leak could be closed, and in 2 (3.4%) patients the leak was missed because of misinterpretation of the imaging studies. One of these patients underwent successful reoperation, and the other patient decided to undergo surgery at another institution. Two other patients had to undergo reoperation because of insufficient closure and a persisting leak. The rate of permanent neurological deficit was 1.7%, the revision rate for a persisting or recurring leak was 3.4%, and the overall revision rate was 10.3%. The rate of successful sealing during the primary closure attempt was 96.6% and 3.4% patients needed a secondary attempt. Clinical short-term outcome at discharge was unchanged in 14 patients and improved in 25 patients, and 19 patients had signs of rebound intracranial hypertension.

CONCLUSIONS Minimally invasive surgery with tubular retractors and a tailored interlaminar fenestration and, if needed, a transdural approach is safe and effective for the treatment of spinal CSF leaks. The authors suggest performing a minimally invasive closure of spinal CSF leaks in specialized centers.

Minimally Invasive Retropleural Thoracic Diskectomy: Step-by-Step Operative Planning, Execution, and Results

Operative Neurosurgery 23:E220–E227, 2022

Thoracic disk herniation is rare and difficult to treat. The minimally invasive lateral retropleural approach to the thoracic spine enables the surgeon to decompress the neural elements and minimize thecal sac manipulation through direct visualization with less exposure-related morbidity.

OBJECTIVE: To provide a detailed step-by-step overview of the minimally invasive retropleural approach for thoracic diskectomies, including preoperative planning through postoperative care as practiced at our institution.

METHODS: Lateral retropleural thoracic diskectomies performed at a single institution from July 1, 2017, to June 30, 2020, were reviewed. Clinical and outcome data were collected and analyzed. The retropleural approach was divided into several components: relevant anatomy, indications and contraindications, preoperative setup, exposure and approach, diskectomy, and closure and postoperative care.

RESULTS: Twelve patients were treated during the study interval. Their average (SD) age was 44.2 (9.5) years; 10 of 12 were men. Eleven patients presented with thoracic myelopathy. The level treated ranged from T6-7 to T12-L1. Disk herniations were calcified in 10 of 12 patients. These lesions were approached from the left side in 7 of 12 patients. Six patients had complications, none of which were neurological. Chest tubes were placed for pleural violation, pneumothorax, or hemothorax in 3 patients. Two patients experienced postoperative abdominal pseudohernia. Neurological symptoms were stable or improved in all patients. The median (IQR) Nurick scale improved from 3.0 (2.0-3.0) preoperatively to 1.0 (0-3.0) (P = .026) postoperatively.

CONCLUSION: Lateral retropleural diskectomy enables safe, efficient resection of most thoracic disks while minimizing patient morbidity.

Prognostic data analysis of surgical treatments for intracerebral hemorrhage

Neurosurgical Review (2022) 45:2733–2744

Spontaneous intracerebral hemorrhage (ICH) is a commonly occurring disease in neurosurgery, yet its surgical treatment is controversial.

This paper pertains to the study of the effects of different treatment regimens on the outcome of ICH population. Based on a globally shared third-party MIMIC-III database, the researchers firstly described the dissimilarities in survival probability, mortality, and neurological recovery among mainstream treatments for ICH; secondly, patient classification was determined by important clinical features; and outcome variations among treatment groups were compared.

The 28-day, 90-day, and in-hospital mortality in the craniotomy group were significantly lower than minimally invasive surgery (MIS) and non-surgical group patients; and, the medium/long-term mortality in MIS group was significantly lower than the non-surgical group. The craniotomy group positively correlated with short-term GCS recovery compared with the MIS group; no difference existed between the non-surgical and MIS groups. The craniotomy group 90-day survival probability and short-term GCS recovery were superior to the other two treatments in the subgroups of first GCS 3–12; this tendency also presented in the MIS group over non-surgical group. For milder patients (first GCS > 12), the three treatment regimens had a minimal effect on patient survival, but the non-surgical group showed an advantage in short-term GCS recovery.

Craniotomy patients have a lower mortality and a better short-term neurological recovery in an ICH population, especially in short-to-medium term mortality and short-term neurological recovery over MIS patients. In addition, surgical treatment is recommendable for patients with a GCS ≤ 12.

Ninety-day complication, revision, and readmission rates for current-generation robot-assisted thoracolumbar spinal fusion surgery

J Neurosurg Spine 36:841–848, 2022

Robotics is a major area for research and development in spine surgery. The high accuracy of robot-assisted placement of thoracolumbar pedicle screws is documented in the literature. The authors present the largest case series to date evaluating 90-day complication, revision, and readmission rates for robot-assisted spine surgery using the current generation of robotic guidance systems.

METHODS An analysis of a retrospective, multicenter database of open and minimally invasive thoracolumbar instrumented fusion surgeries using the Mazor X or Mazor X Stealth Edition robotic guidance systems was performed. Patients 18 years of age or older and undergoing primary or revision surgery for degenerative spinal conditions were included. Descriptive statistics were used to calculate rates of malpositioned screws requiring revision, as well as overall complication, revision, and readmission rates within 90 days.

RESULTS In total, 799 surgical cases (Mazor X: 48.81%; Mazor X Stealth Edition: 51.19%) were evaluated, involving robot-assisted placement of 4838 pedicle screws. The overall intraoperative complication rate was 3.13%. No intraoperative implant-related complications were encountered. Postoperatively, 129 patients suffered a total of 146 complications by 90 days, representing an incidence of 16.1%. The rate of an unrecognized malpositioned screw resulting in a new postoperative radiculopathy requiring revision surgery was 0.63% (5 cases). Medical and pain-related complications unrelated to hardware placement accounted for the bulk of postoperative complications within 90 days. The overall surgical revision rate at 90 days was 6.63% with 7 implant-related revisions, representing an implant-related revision rate of 0.88%. The 90-day readmission rate was 7.13% with 2 implant-related readmissions, representing an implant-related readmission rate of 0.25% of cases.

CONCLUSIONS The results of this multicenter case series and literature review suggest current-generation robotic guidance systems are associated with low rates of intraoperative and postoperative implant-related complications, revisions, and readmissions at 90 days. Future outcomes-based studies are necessary to evaluate complication, revision, and readmission rates compared to conventional surgery.

 

Minimally invasive versus open lumbar spinal fusion: a matched study investigating patient-reported and surgical outcomes

J Neurosurg Spine 36:753–766, 2022

With the expanding indications for and increasing popularity of minimally invasive surgery (MIS) for lumbar spinal fusion, large-scale outcomes analysis to compare MIS approaches with open procedures is warranted.

METHODS The authors queried the Quality Outcomes Database for patients who underwent elective lumbar fusion for degenerative spine disease. They performed optimal matching, at a 1:2 ratio between patients who underwent MIS and those who underwent open lumbar fusion, to create two highly homogeneous groups in terms of 33 baseline variables (including demographic characteristics, comorbidities, symptoms, patient-reported scores, indications, and operative details). The outcomes of interest were overall satisfaction, decrease in Oswestry Disability Index (ODI), and back and leg pain, as well as hospital length of stay (LOS), operative time, reoperations, and incidental durotomy rate. Satisfaction was defined as a score of 1 or 2 on the North American Spine Society scale. Minimal clinically important difference (MCID) in ODI was defined as ≥ 30% decrease from baseline. Outcomes were assessed at the 3- and 12-month follow-up evaluations.

RESULTS After the groups were matched, the MIS and open groups consisted of 1483 and 2966 patients, respectively. Patients who underwent MIS fusion had higher odds of satisfaction at 3 months (OR 1.4, p = 0.004); no difference was demonstrated at 12 months (OR 1.04, p = 0.67). Lumbar stenosis, single-level fusion, higher American Society of Anesthesiologists Physical Status Classification System grade, and absence of spondylolisthesis were most prominently associated with higher odds of satisfaction with MIS compared with open surgery. Patients in the MIS group had slightly lower ODI scores at 3 months (mean difference 1.61, p = 0.006; MCID OR 1.14, p = 0.0495) and 12 months (mean difference 2.35, p < 0.001; MCID OR 1.29, p < 0.001). MIS was also associated with a greater decrease in leg and back pain at both follow-up time points. The two groups did not differ in operative time and incidental durotomy rate; however, LOS was shorter for the MIS group. Revision surgery at 12 months was less likely for patients who underwent MIS (4.1% vs 5.6%, p = 0.032).

CONCLUSIONS In patients who underwent lumbar fusion for degenerative spinal disease, MIS was associated with higher odds of satisfaction at 3 months postoperatively. No difference was demonstrated at the 12-month follow-up. MIS maintained a small, yet consistent, superiority in decreasing ODI and back and leg pain, and MIS was associated with a lower reoperation rate.

Single-position prone lateral transpsoas approach: early experience and outcomes

J Neurosurg Spine 36:358–365, 2022

Lateral lumbar interbody fusion (LLIF) via a transpsoas approach is a workhorse minimally invasive approach for lumbar arthrodesis that is often combined with posterior pedicle screw fixation. There has been increasing interest in performing single-position surgery, allowing access to the anterolateral and posterior spine without requiring patient repositioning. The feasibility of the transpsoas approach in patients in the prone position has been reported. Herein, the authors present a consecutive case series of all patients who underwent single-position prone transpsoas LLIF performed by an individual surgeon since adopting this approach.

METHODS A retrospective review was performed of a consecutive case series of adult patients (≥ 18 years old) who underwent single-position prone LLIF for any indication between October 2019 and November 2020. Pertinent operative details (levels, cage use, surgery duration, estimated blood loss, complications) and 3-month clinical outcomes were recorded. Intraoperative and 3-month postoperative radiographs were reviewed to assess for interbody subsidence.

RESULTS Twenty-eight of 29 patients (97%) underwent successful treatment with the prone lateral approach over the study interval; the approach was aborted in 1 patient, whose data were excluded. The mean (SD) age of patients was 67.9 (9.3) years; 75% (21) were women. Thirty-nine levels were treated: 18 patients (64%) had single-level fusion, 9 (32%) had 2-level fusion, and 1 (4%) had 3-level fusion. The most commonly treated levels were L3–4 (n = 15), L2–3 (n = 12), and L4–5 (n = 11). L1–2 was fused in 1 patient. The mean operative time was 286.5 (100.6) minutes, and the mean retractor time was 29.2 (13.5) minutes per level. The mean fluoroscopy duration was 215.5 (99.6) seconds, and the mean intraoperative radiation dose was 170.1 (94.8) mGy. Intraoperative subsidence was noted in 1 patient (4% of patients, 3% of levels). Intraoperative lateral access complications occurred in 11% of patients (1 cage repositioning, 2 inadvertent ruptures of anterior longitudinal ligament). Subsidence occurred in 5 of 22 patients (23%) with radiographic follow-up, affecting 6 of 33 levels (18%). Postoperative functional testing (Oswestry Disability Index, SF-36, visual analog scale–back and leg pain) identified significant improvement.

CONCLUSIONS This single-surgeon consecutive case series demonstrates that this novel technique is well tolerated and has acceptable clinical and radiographic outcomes. Larger patient series with longer follow-up are needed to further elucidate the safety profile and long-term outcomes of single-position prone LLIF.

Double tubular minimally invasive spine surgery: a novel technique expands the surgical visual field during resection of intradural pathologies

J Neurosurg Spine 36:160–163, 2022

A major challenge of a minimally invasive spinal approach (MIS) is maintaining freedom of maneuverability through small operative corridors. Unfortunately, during tubular resection of intradural pathologies, the durotomy and its accompanying tenting sutures offer a smaller operating window than the maximum surface of the tube’s base. The objective of this study was to evaluate if a novel double tubular technique could expand the surgical visual field during MIS resection of intradural pathologies.

METHODS A total of 25 MIS resections of intradural extramedullary pathologies were included. A posterior tubular interlaminar fenestration was performed in all surgeries. A durotomy covering the whole diameter of the tubular base was the standard in all cases. After placement of two tenting sutures on each side of the durotomy and application of tension, the resulting surface of the achieved dura fenestration was measured after optical analysis of the intraoperative video. In the next step, a second tube, 2 mm thinner than and the same length as the first, was inserted telescopically into the first tube, resulting an angulated fulcrum effect on the tenting sutures.

RESULTS Optical surface analysis of the dura fenestration before and after the second tubular insertion verified a significant widening of the visual field of 43.1% (mean 18.84 mm2, 95% CI 16.8–20.8, p value < 0.001). There were no ruptured tenting sutures through the increased tension. Postoperative MRIs verified complete resection of the pathologies.

CONCLUSIONS Inserting a second tube telescopically during posterior minimally invasive tubular spinal intradural surgery leads to an angulated fulcrum effect on the dura tenting sutures which consequently increases the surface of the dura fenestration and induces a meaningful widening of the visual field.

The trans‑laminar, facet‑joint sparing minimal invasive approach for ventral dural repair in spontaneous intracranial hypotension

Acta Neurochirurgica (2021) 163:3015–3020

We describe the minimally invasive, facet-sparing postero-lateral approach to the thoracic spine for a ventral dural repair in a patient with intracranial hypotension secondary to a spontaneous dural breach.

Methods We performed a minimally invasive approach using a short paramedian posterior skin incision followed by a 10 × 10 mm targeted trans-laminar approach, to achieve a microsurgical repair of a symptomatic ventral dural defect causing severe disability.

Conclusion The facet-sparing postero-lateral approach is safe and effective in the surgical management of thoracic dural tears, even in the most anterior ones, and avoids the traditional costotransversectomy.