Single position robot-assisted pedicle screw placement with S2-alar-iliac fixation in lateral decubitus: cadaveric feasibility study and early clinical experience.

OBJECTIVES: Single position lateral fusion with robotic assistance eliminates the need for surgical staging while harnessing the precision of robotic adjuncts. We expand on this technique by demonstrating the technical feasibility of placing bilateral pedicle screws with S2-alar-iliac (S2AI) fixation while in the lateral position. METHODS: A cadaveric study was performed using 12 human specimens. A retrospective clinical series was also performed for patients who had undergone robot-assisted placement of S2AI screws in lateral decubitus between June 2020 and June 2022. Case demographics, implant placement time, implant size, screw accuracy, and complications were recorded. Early postoperative radiographic outcomes were reported. RESULTS: In the cadaveric series, a total of 126 screws were placed with robotic assistance in 12 cadavers of which 24 screws were S2AI. There were four breaches from pedicle screws and none with S2AI screws for an overall accuracy rate of 96.8%. In the clinical series, four patients (all male, mean age 65.8 years) underwent single position lateral surgery with S2AI distal fixation. Mean BMI was 33.6 and mean follow-up was 20.5 months. Mean radiographic improvements were lumbar lordosis 12.3 ± 4.7°, sagittal vertical axis 1.5 ± 2.1 cm, pelvic tilt 8.5 ± 10.0°, and pelvic incidence-lumbar lordosis mismatch 12.3 ± 4.7°. A total of 42 screws were placed of which eight screws were S2AI. There were two breaches from pedicle screws and none from S2AI screws for an overall accuracy rate of 95.2%. No repositioning or salvage techniques were required for the S2AI screws. CONCLUSIONS: We demonstrate here the technical feasibility of single position robot-assisted placement of S2-alar-iliac screws in the lateral decubitus position for single position surgery.

Single position L5-S1 lateral ALIF with simultaneous robotic posterior fixation is safe and improves regional alignment and lordosis distribution index.

PURPOSE: Minimally invasive single position lateral ALIF at L5-S1 with simultaneous robot-assisted posterior fixation has technical and anatomic considerations that need further description. METHODS: This is a retrospective case series of single position lateral ALIF at L5-S1 with robotic assisted fixation. End points included radiographic parameters, lordosis distribution index (LDI), complications, pedicle screw accuracy, and inpatient metrics. RESULTS: There were 17 patients with mean age of 60.5 years. Eight patients underwent interbody fusion at L5-S1, five patients at L4-S1, two patients at L3-S1, and one patient at L2-S1 in single lateral position. Operative times for 1-level and 2-level cases were 193 min and 278 min, respectively. Mean EBL was 71 cc. Mean improvements in L5-S1 segmental lordosis were 11.7 ± 4.0°, L1-S1 lordosis of 4.8 ± 6.4°, sagittal vertical axis of - 0.1 ± 1.7 cm°, pelvic tilt of - 3.1 ± 5.9°, and pelvic incidence lumbar-lordosis mismatch of - 4.6 ± 6.4°. Six patients corrected into a normal LDI (50-80%) and no patients became imbalanced over a mean follow-up period of 14.4 months. Of 100 screws placed in lateral position with robotic assistance, there were three total breaches (two lateral grade 3, one medial grade 2) for a screw accuracy of 97.0%. There were no neurologic, vascular, bowel, or ureteral injuries, and no implant failure or reoperation. CONCLUSION: Single position lateral ALIF at L5-S1 with simultaneous robotic placement of pedicle screws by a second surgeon is a safe and effective technique that improves global alignment and lordosis distribution index.

Minimally invasive multiple-rod constructs with robotics planning in adult spinal deformity surgery: a case series.

PURPOSE: Multiple-rod constructs (MRCs) are often used in deformity correction for increased stability and rigidity. There are currently no reports showing minimally invasive placement of MRCs in adult deformity surgery and its technical feasibility through preoperative software planning. METHODS: Data were collected retrospectively from medical records of six consecutive patients who underwent minimally invasive MRCs with robotics planning by a single surgeon at an academic center between March-August 2020. RESULTS: A total of six patients (4 females, mean age 69.7 years) underwent minimally invasive long-segment (6 +) posterior fixation with multiple rods (3 +) using the Mazor X Stealth Edition robotics platform. Average follow-up was 14.3 months. All patients underwent oblique lumbar interbody fusion (OLIF) as a first stage, followed by second stage posterior fixation in the same day. The mean number of levels posteriorly instrumented was 8.8. One patient underwent 3 rod fixation (1 iliac, 2 S2AI) and 5 patients underwent quad rod fixation (2 iliac, 2 S2AI). The mean time to secure all rods was 8 min 36 s. Mean improvement in spinopelvic parameters was -4.9 cm sagittal vertical axis, 18.0° lumbar lordosis, and -10.7° pelvic tilt with an average pelvic incidence of 62.5°. Estimated blood loss (EBL) was 100-250 cc with no blood transfusions, and all but one patient ambulated on postoperative day 1 or 2. CONCLUSION: Spinal robotics brings us into a new era of minimally invasive construct design. To our knowledge, this is the first description of the technical feasibility of MRCs in minimally invasive adult spinal deformity surgery.

The impact of rural residence on adult brain cancer survival in the United States.

PURPOSE: Rural/urban disparities in brain cancer survival have been reported. However, disparities by cancer type or in the United States as a whole remain poorly understood. Using the Surveillance, Epidemiology, and End Results (SEER) 18 registries database, we examined brain cancer survival by rural/urban residence defined by Rural-Urban Continuum Codes (RUCCs). METHODS: We obtained data from SEER 18 registries for individuals aged 20 years and older with a first primary malignant brain cancer from 2001 to 2011. Rural/urban residence at diagnosis was defined using both metropolitan/non-metropolitan county classifications and individual RUCC categories. We used Cox proportional hazards regression to compute adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between rural/urban residence and brain cancer survival. RESULTS: Among 37,581 cancer cases, 77.9% were non-Hispanic White, 56.5% were male, and 88.7% lived in a metropolitan county. Brain cancer patients living in the most rural counties had a significant increased risk of cancer death compared to those living in the most urban counties (HR 1.15; 95% CI 1.01-1.31). Those living in non-metropolitan counties had a similar risk of cancer death compared to those living in metropolitan counties (HR 1.01; 95% CI 0.97-1.06). Effect modification was observed overall by cancer type, with non-specified oligodendroglioma (HR 1.35; 95% CI 1.01-1.81) showing the greatest effect. CONCLUSION: After adjusting for confounding factors, our results suggest that rural residence has a modest effect on brain cancer survival, and that this disparity may vary by cancer type. Future research should explore differences in treatment strategies between rural and urban brain cancer patients.

Efficacy of riluzole in the treatment of spinal cord injury: a systematic review of the literature.

OBJECTIVERiluzole is a glutamatergic modulator that has recently shown potential for neuroprotection after spinal cord injury (SCI). While the effects of riluzole are extensively documented in animal models of SCI, there remains heterogeneity in findings. Moreover, there is a paucity of data on the pharmacology of riluzole and its effects in humans. For the present study, the authors systematically reviewed the literature to provide a comprehensive understanding of the effects of riluzole in SCI.METHODSThe PubMed database was queried from 1996 to September 2018 to identify animal studies and clinical trials involving riluzole administration for SCI. Once articles were identified, they were processed for year of publication, study design, subject type, injury model, number of subjects in experimental and control groups, dose, timing/route of administration, and outcomes.RESULTSA total of 37 studies were included in this study. Three placebo-controlled clinical trials were included with a total of 73 patients with a mean age of 39.1 years (range 18-70 years). For the clinical trials included within this study, the American Spinal Injury Association Impairment Scale distributions for SCI were 42.6% grade A, 25% grade B, 26.6% grade C, and 6.2% grade D. Key findings from studies in humans included decreased nociception, improved motor function, and attenuated spastic reflexes. Twenty-six animal studies (24 in vivo, 1 in vitro, and 1 including both in vivo and in vitro) were included. A total of 520 animals/in vitro specimens were exposed to riluzole and 515 animals/in vitro specimens underwent other treatment for comparison. The average dose of riluzole for intraperitoneal, in vivo studies was 6.5 mg/kg (range 1-10 mg/kg). Key findings from animal studies included behavioral improvement, histopathological tissue sparing, and modified electrophysiology after SCI. Eight studies examined the pharmacology of riluzole in SCI. Key findings from pharmacological studies included riluzole dose-dependent effects on glutamate uptake and its modified bioavailability after SCI in both animal and clinical models.CONCLUSIONSSCI has many negative sequelae requiring neuroprotective intervention. While still relatively new in its applications for SCI, both animal and human studies demonstrate riluzole to be a promising pharmacological intervention to attenuate the devastating effects of this condition.

Immunosuppressive mechanisms for stem cell transplant survival in spinal cord injury.

Spinal cord injury (SCI) has been associated with a dismal prognosis-recovery is not expected, and the most standard interventions have been temporizing measures that do little to mitigate the extent of damage. While advances in surgical and medical techniques have certainly improved this outlook, limitations in functional recovery continue to impede clinically significant improvements. These limitations are dependent on evolving immunological mechanisms that shape the cellular environment at the site of SCI. In this review, we examine these mechanisms, identify relevant cellular components, and discuss emerging treatments in stem cell grafts and adjuvant immunosuppressants that target these pathways. As the field advances, we expect that stem cell grafts and these adjuvant treatments will significantly shift therapeutic approaches to acute SCI with the potential for more promising outcomes.

Posterolateral cervical transpedicular corpectomy for the surgical management of metastatic tumor.

Management of metastatic spinal disease in the upper cervical spine can be particularly challenging. Depending on the level of the lesion and the patient's anatomy, multiple anterior approaches have been described for resection of the cancer, followed by posterior fixation and instrumentation. Although a single-stage posterolateral approach is now well established for thoracic pathology, less is known about the applicability of these principles when applied as an approach to the cervical spine. The authors present here a case using a posterolateral transpedicular approach for corpectomy and graft placement for circumferential reconstruction as a treatment of metastatic disease in the cervical spine to illustrate the feasibility of this technique, especially in the setting where the patient's anatomy or pathology may impede an anterior or combined circumferential approach.

A Portable Shoulder-Mounted Camera System for Surgical Education in Spine Surgery.

The past several years have demonstrated an increased recognition of operative videos as an important adjunct for resident education. Currently lacking, however, are effective methods to record video for the purposes of illustrating the techniques of minimally invasive (MIS) and complex spine surgery. We describe here our experiences developing and using a shoulder-mounted camera system for recording surgical video. Our requirements for an effective camera system included wireless portability to allow for movement around the operating room, camera mount location for comfort and loupes/headlight usage, battery life for long operative days, and sterile control of on/off recording. With this in mind, we created a shoulder-mounted camera system utilizing a GoPro™ HERO3+, its Smart Remote (GoPro, Inc., San Mateo, California), a high-capacity external battery pack, and a commercially available shoulder-mount harness. This shoulder-mounted system was more comfortable to wear for long periods of time in comparison to existing head-mounted and loupe-mounted systems. Without requiring any wired connections, the surgeon was free to move around the room as needed. Over the past several years, we have recorded numerous MIS and complex spine surgeries for the purposes of surgical video creation for resident education. Surgical videos serve as a platform to distribute important operative nuances in rich multimedia. Effective and practical camera system setups are needed to encourage the continued creation of videos to illustrate the surgical maneuvers in minimally invasive and complex spinal surgery. We describe here a novel portable shoulder-mounted camera system setup specifically designed to be worn and used for long periods of time in the operating room.

Intracranial complications associated with spinal surgery.

PURPOSE: Though rare, intracranial complications have been reported as a result from spinal surgery. Most if not all of these are a result of intracranial hypotension from durotomy and cerebrospinal fluid (CSF) leak. We aimed to characterize these complications across a large postoperative population at our institution. METHODS: We conducted a retrospective review of all patients who underwent spinal surgery at our institution by four neurosurgeons from July 2008 to August 2013. RESULTS: Our review yielded 1113 consecutive patients who underwent spinal surgery for a total of 1396 procedures. Intracranial imaging using either computed tomography or magnetic resonance imaging was obtained on 59 (4.2%) patients after a procedure due to neurologic change. Six patients (0.4%) were found to have intracranial findings of subdural hygroma (4 patients), remote cerebellar hemorrhage (1 patient), or subdural hematoma (1 patient). CONCLUSION: Intracranial complications from spinal surgery are a rare event. We demonstrate an incidence of 0.4% of total intracranial pathology after spinal surgery. A strong clinical suspicion must be maintained after durotomy or CSF leak due to these infrequent but potentially life-threatening complications.

S-1 and S-2-alar-iliac screw fixation via intraoperative navigation.

Adult deformity patients often require fixation to the sacrum and pelvis for construct stability and improved fusion rates. Although certain sacropelvic fixation techniques can be challenging, the availability of intraoperative navigation has made many of these techniques more feasible. In this video case presentation, the authors demonstrate the techniques of S-1 bicortical screw and S-2-alar-iliac screw fixation under intraoperative navigation in a 67-year-old female. This instrumentation placement was part of an overall T-10-pelvis construct for the correction of adult spinal deformity. The video can be found here: https://youtu.be/3HZo-80jQr8 .

Minimally invasive L5-S1 oblique lumbar interbody fusion with anterior plate.

Lumbar interbody fusion is an important technique for the treatment of degenerative disc disease and degenerative scoliosis. The oblique lumbar interbody fusion (OLIF) establishes a minimally invasive retroperitoneal exposure anterior to the psoas and lumbar plexus. In this video case presentation, the authors demonstrate the techniques of the OLIF at L5-S1 performed on a 69-year-old female with degenerative scoliosis as one component of an overall strategy for her deformity correction. The video can be found here: https://youtu.be/VMUYWKLAl0g .

Complications associated with the Dynesys dynamic stabilization system: a comprehensive review of the literature.

The Dynesys dynamic stabilization system is an alternative to rigid instrumentation and fusion for the treatment of lumbar degenerative disease. Although many outcomes studies have shown good results, currently lacking is a comprehensive report on complications associated with this system, especially in terms of how it compares with reported complication rates of fusion. For the present study, the authors reviewed the literature to find all studies involving the Dynesys dynamic stabilization system that reported complications or adverse events. Twenty-one studies were included for a total of 1166 patients with a mean age of 55.5 years (range 39-71 years) and a mean follow-up period of 33.7 months (range 12.0-81.6 months). Analysis of these studies demonstrated a surgical-site infection rate of 4.3%, pedicle screw loosening rate of 11.7%, pedicle screw fracture rate of 1.6%, and adjacent-segment disease (ASD) rate of 7.0%. Of studies reporting revision surgeries, 11.3% of patients underwent a reoperation. Of patients who developed ASD, 40.6% underwent a reoperation for treatment. The Dynesys dynamic stabilization system appears to have a fairly similar complication-rate profile compared with published literature on lumbar fusion, and is associated with a slightly lower incidence of ASD.

Minimally Invasive L4-5 Oblique Lumbar Interbody Fusion With Robot-Assisted Single-Position Posterior Fixation: 2-Dimensional Operative Video.

We present here a 58-year-old female patient with L4-5 spondylolisthesis, who underwent a minimally invasive L4-5 oblique lumbar interbody fusion (OLIF) with robot-assisted bilateral posterior instrumented fixation in a single lateral position (Mazor X Stealth Edition, Medtronic). There has been interest in detailed video-based descriptions of single-position surgery with lateral approach interbody fusions, either in the prone or lateral decubitus position.1-6 Particularly, the addition of robotics has been shown to help increase overall operating efficiency in the lateral position with reduced case times even with the increased up-front robot setup time.7,8 The OLIF, also known as an anterior-to-psoas approach, allows for single-position posterior fixation and can be very effective at L4-5 where the anatomy of the iliac crest or lumbar plexus does not preclude this surgical corridor the way it could in the transpsoas lateral lumbar interbody fusion. Clinical outcomes between these 2 lateral approaches have been shown to be very good,9 and OLIF has reduced blood loss while still restoring alignment parameters compared with anterior lumbar interbody fusion, with better fusion and reduced subsidence compared with transforaminal lumbar interbody fusion.10,11 To our knowledge, this is the first video demonstrating a view of the OLIF approach through a high-definition retractor-based camera (MaxView Camera, Viseon Inc). There is no identifying patient information in this video. The participants and any identifiable individuals consented to publication of his/her image, and the patient consented to the procedure.

Preoperative Robotics Planning Facilitates Complex Construct Design in Robot-Assisted Minimally Invasive Adult Spinal Deformity Surgery-A Preliminary Experience.

(1) Background: The correction of adult spinal deformity (ASD) can require long, complex constructs with multiple rods which traverse important biomechanical levels to achieve multi-pelvic fixation. Minimally invasive (MIS) placement of these constructs has historically been difficult. Advanced technologies such as spinal robotics platforms can facilitate the design and placement of these constructs and further enable these surgical approaches in MIS deformity surgery. (2) Methods: A retrospective study was performed on a series of ASD patients undergoing MIS deformity correction with ≥eight fusion levels to the lower thoracic spine with preoperative robotic construct planning and robot-assisted pedicle screw placement. (3) Results: There were 12 patients (10 female, mean age 68.6 years) with a diagnosis of either degenerative scoliosis (8 patients) or sagittal imbalance (4 patients). All underwent preoperative robotic planning to assist in MIS robot-assisted percutaneous or transfascial placement of pedicle and iliac screws with multiple-rod constructs. Mean operative values per patient were 9.9 levels instrumented (range 8-11), 3.9 interbody cages (range 2-6), 3.3 iliac fixation points (range 2-4), 3.3 rods (range 2-4), 18.7 screws (range 13-24), estimated blood loss 254 cc (range 150-350 cc), and operative time 347 min (range 242-442 min). All patients showed improvement in radiographic sagittal, and, if applicable, coronal parameters. Mean length of stay was 5.8 days with no ICU admissions. Ten patients ambulated on POD 1 or 2. Of 224 screws placed minimally invasively, four breaches were identified on intraoperative CT and repositioned (three lateral, one medial) for a robot-assisted screw accuracy of 98.2%. (4) Conclusions: Minimally invasive long-segment fixation for adult spinal deformity surgery has historically been considered laborious and technically intensive. Preoperative robotics planning facilitates the design and placement of even complex multi-rod multi-pelvic fixation for MIS deformity surgery.

Brachioradial Pruritus Caused by Cervical Disc Herniation Precipitated by Trauma Treated with Anterior Cervical Discectomy and Fusion: Report of Two Cases and Review of the Literature.

Brachioradial pruritis (BRP) is a rare form of dermatomal pruritis that appears to be caused both by cervical radiculopathy and exposure to ultraviolet-light, although the exact pathophysiology for the manifestation of these symptoms remains to be determined. A diagnosis of BRP is typically confirmed with the "ice-pack" test and evidence of cervical spine pathology using magnetic resonance imaging. Treatment options consist of application of ice, reduction in sun exposure, and topical capsaicin, antiepileptics, or tricyclic antidepressants. Patients with refractory symptoms and cervical spine pathology may be candidates for surgical decompression, particularly at the C5 and C6 levels. However, there are currently no established guidelines to treat BRP, or surgical procedures that have shown to be superior. Here, we report two cases of cervical disc herniations after traumatic events that presented as BRP. Both cases were successfully treated with anterior cervical discectomy and fusion with complete resolution of symptoms.

Single-Position Robotic-Assisted Prone Lateral Fusion: Technical Description and Feasibility.

Single-position lateral interbody fusion surgery has gained traction over the years because of reduced surgical time and improved operating theater workflow. With the introduction of robotics in spine surgery, surgeons can place pedicle screws with a high degree of accuracy and efficiency; moreover, the robot allows us to localize the disk space and perform endplate preparation accurately with minimal radiation. In this study, we discuss the potential synergistic benefits of integrating robotic-assisted spine surgery and singleposition prone lateral surgery. We share our technique and provide the operative nuances of using the Mazor X Stealth Edition system (Medtronic, Minneapolis, MN, USA). We highlighted the potential synergistic benefits of integrating both the prone lateral and robotic-assisted surgical techniques, including the challenges encountered. This approach is not meant to replace other techniques or be used in all patients. Instead, it adds to our arsenal for managing spine fusion.

Spinal Robotics in Adult Spinal Deformity Surgery: A Systematic Review.

Spinal robotics have the potential to improve the consistency of outcomes in adult spinal deformity (ASD) surgery. The objective of this paper is to assess the accuracy of pedicle and S2 alar-iliac (S2AI) screws placed with robotic guidance in ASD patients. PubMed Central, Google Scholar, and an institutional library database were queried until May 2023. Articles were included if they described ASD correction via robotic guidance and pedicle and/or S2AI screw accuracy. Articles were excluded if they described pediatric/adolescent spinal deformity or included outcomes for both ASD and non-ASD patients without separating the data. Methodological quality was assessed using the Newcastle-Ottawa scale. Primary endpoints were pedicle screw accuracy based on the Gertzbein-Robbins Scale and self-reported accuracy percentages for S2AI screws. Data were extracted for patient demographics, operative details, and perioperative outcomes and assessed using descriptive statistics. Five studies comprising 138 patients were included (mean age 66.0 years; 85 females). A total of 1,508 screws were inserted using robotic assistance (51 S2AI screws). Two studies assessing pedicle screws reported clinically acceptable trajectory rates of 98.7% and 96.0%, respectively. Another study reported a pedicle screw accuracy rate of 95.5%. Three studies reported 100% accuracy across 51 total S2AI screws. Eight total complications and 4 reoperations were reported. Current evidence supports the application of robotics in ASD surgery as safe and effective for placement of both screw types. However, due to the paucity of data, a comprehensive assessment of its incremental benefit over other techniques cannot be made. Further work using expanded cohorts is merited.

Oblique anterior column realignment with a mini-open posterior column osteotomy for minimally invasive adult spinal deformity correction: illustrative case.

BACKGROUND: Adult spinal deformity (ASD) occurs from progressive anterior column collapse due to disc space desiccation, compression fractures, and autofusion across disc spaces. Anterior column realignment (ACR) is increasingly recognized as a powerful tool to address ASD by progressively lengthening the anterior column through the release of the anterior longitudinal ligament during lateral interbody approaches. Here, we describe the application of minimally invasive ACR through an oblique antepsoas corridor for deformity correction in a patient with adult degenerative scoliosis and significant sagittal imbalance. OBSERVATIONS: A 65-year-old female with a prior history of L4-5 transforaminal lumbar interbody fusion and morbid obesity presented with refractory, severe low-back and lower-extremity pain. Preoperative radiographs showed significant sagittal imbalance. Computed tomography showed a healed L4-5 fusion and a vacuum disc at L3-4 and L5-S1, whereas magnetic resonance imaging was notable for central canal stenosis at L3-4. The patient was treated with a first-stage L5-S1 lateral anterior lumbar interbody fusion with oblique L2-4 ACR. The second-stage posterior approach consisted of a robot-guided minimally invasive T10-ilium posterior instrumented fusion with a mini-open L2-4 posterior column osteotomy (PCO). Postoperative radiographs showed the restoration of her sagittal balance. There were no complications. LESSONS: Oblique ACR is a powerful minimally invasive tool for sagittal plane correction. When combined with a mini-open PCO, substantial segmental lordosis can be achieved while eliminating the need for multilevel PCO or invasive three-column osteotomies.

A systematic review of pseudarthrosis and reoperation rates in minimally invasive adult spinal deformity correction.

Background/objective: The recent development of minimally invasive surgical techniques (MIS) has made possible the correction of adult spinal deformity (ASD) with less blood loss and shorter hospital stays. However, minimally invasive placement of pedicle screws at the proximal level of the construct can increase pseudarthrosis risk, leading to implant failure, kyphosis, and reoperations. We aggregate existing literature to describe pseudarthrosis rates at the proximal thoracic or thoracolumbar junction in MIS and subsequent reoperation rates. Methods: After a three-tied search strategy in PubMed, we identified 9 articles for study inclusion, describing outcomes from MIS correction of ASD, pseudarthrosis as complication, and surgery on 4+ levels. Baseline patient characteristics and combined rates of pseudarthrosis and reoperation were calculated. Results: A total of 482 patients were studied with an average [range] age of 65.5 [60.4,72], 6.3 [4.4,11] levels fused per patient, follow-up time of 28.3 [12,39] months, and 64.8% females. Pseudarthrosis was reported in 28 of 482 pooled patients (5.8%) of which 15 of 374 pooled patients (4.0%) ultimately underwent a reoperation for pseudarthrosis. Post-operative characteristics included an estimated blood loss (EBL) of 527.1 [241,1466] mL, operating time of 297.9 [183,475] minutes, and length of stay of 7.7 [5,10] days. Among the papers comparing MIS to open surgery, all reported a significantly lower EBL in patients treated with MIS. Conclusion: This analysis demonstrate a measurable pseudarthrosis risk when using MIS to treat ASD, overwhelming requiring reoperation. The benefits of MIS must be considered against the drawbacks of pseudarthrosis when determining ASD management.

Risks Associated with Surgical Management of Lumbosacral Transitional Vertebrae: Systematic Review of Surgical Considerations and Illustrative Case.

BACKGROUND: Lumbosacral transitional vertebrae (LSTV) are congenital anomalies of the L5-S1 segments characterized by either sacralization of the most caudal lumbar vertebra or lumbarization of the most cephalad sacral vertebra. This variation in anatomy exposes patients to additional surgical risks. METHODS: In order to shed light on surgical considerations reported for lumbar spine cases involving LSTV as described in the extant literature, we performed a systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. We also present a case example in which wrong level surgery was avoided due to anatomical understanding of LSTV. RESULTS: A 48-year-old female presented with severe back pain after sustaining a fall from ten feet. The patient exhibited full motor function in all extremities but had begun to experience urinary retention. On initial imaging read, the patient was suspected to have an L1 burst fracture. A review of the imaging demonstrated a transitional vertebra. Therefore, based on the last rib corresponding to T12, the fractured level was L2. This case illustrates the risk LSTV carries for wrong site surgery; appropriate levels were then decompressed and instrumented. On systematic review of the literature according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, a three database literature search identified 39 studies describing 885 patients with LSTV and relevant surgical considerations. The primary indications for surgery were for disc herniation (37%), Bertolotti's syndrome (35%), and spinal stenosis (25%). This cohort displayed a mean follow-up time of 23 months. Reherniation occurred in 12 patients (5.5%). Medical management through steroid injection was 24, 72% (n = 80) for the sample. Wrong level surgery occurred in 1.4% (n = 12) of patients. CONCLUSIONS: LSTV represents a constellation of changes in anatomy beyond just a sacralized or lumbarized vertebra. These anatomical differences expose the patient to additional surgical risks. This case and review of the literature highlight avoidable complications and in particular wrong level surgery.