Background: Right-sided unilateral biportal endoscopic transforaminal lumbar interbody fusion (UBE-TLIF) presents specific ergonomic and technical challenges, particularly during cranial laminotomy, ligamentum flavum resection, preservation of local autograft, endplate preparation, and management of irrigation. We describe a stepwise set of technical refinements designed to address these challenges while maintaining the established principles of UBE-TLIF. Technical Description: The workflow incorporates targeted modifications for right-sided UBE-TLIF. A cranially positioned working portal and caudally positioned viewing portal are planned to optimize triangulation and instrument trajectory. A “feather-brush” laminotomy using progressive cortical thinning with a 4-mm diamond burr facilitates controlled exposure of the ligamentum flavum before Kerrison punch removal. Sequential “Z-sequence” flavotomy maintains anatomical orientation during ligamentum flavum detachment. A three-point drilling technique enables preservation of an intact inferior articular process as structural autograft while simultaneously expanding the operative corridor. Direct intradiscal endoscopic visualization is used for circumferential endplate preparation while preserving the subchondral bone. Gravity-assisted irrigation with continuous outflow and the “fountain sign” provides a practical method for maintaining an appropriate operative field. Portal positioning is additionally planned to facilitate subsequent percutaneous pedicle screw placement. Conclusion: These technical refinements address key ergonomic, biological, and fluid-management challenges encountered during right-sided UBE-TLIF. Integration of controlled bone removal, sequential flavectomy, autograft preservation, direct endplate visualization, and standardized irrigation management may improve procedural reproducibility and facilitate safer execution of UBE-TLIF. Prospective comparative studies are required to determine whether these modifications translate into improved clinical or procedural outcomes.
Unilateral biportal endoscopy (UBE) has become an established minimally invasive technique for lumbar canal stenosis, offering excellent visualization and bilateral decompression while minimizing soft-tissue disruption. Adjacent two-level decompression, however, conventionally requires multiple portal pairs or portal redirection techniques that may increase surgical access or compromise ergonomics. We describe a novel single-skin-incision dual-level UBE decompression using independent fascial corridors, which preserves optimal working trajectories while eliminating the need for an additional cranial portal. A 46-year-old woman presented with a 12-year history of progressive neurogenic claudication and severe back and leg pain refractory to conservative treatment. Magnetic resonance imaging demonstrated severe L4–L5 and L5–S1 central canal, lateral recess, and foraminal stenosis without dynamic instability. Right-sided UBE decompression was performed using two skin incisions. Following standard decompression at L4–L5, the endoscope and instruments were withdrawn, and new fascial openings were created through the same skin incisions to establish independent working and viewing corridors for L5–S1 decompression. This allowed target-specific docking and conventional decompression at both levels without additional portals or specialized instrumentation. The patient was mobilized on the day of surgery with immediate improvement in neurogenic claudication. At 36 h postoperatively, the Visual Analog Scale improved from 7 to 4 for back pain and from 8 to 2 for leg pain, with no new neurological deficits. This technical modification demonstrates the feasibility of decoupling the skin incision from the fascial trajectory to achieve adjacent two-level lumbar decompression through common cutaneous portals while maintaining independent working corridors. The technique exploits favorable geometric planning and lumbar lordosis to preserve instrument triangulation and ergonomic access without prolonged subfascial tunnelling or additional portals. Although larger studies are required to establish its clinical advantages, this simple modification may further reduce the surgical footprint of multilevel UBE decompression while preserving standard operative principles.
Unilateral biportal endoscopy (UBE) is an evolving minimally invasive technique for lumbar spinal stenosis and disc herniation, offering reduced tissue trauma with a wide surgical field. This chapter describes its principles, indications, patient selection, anesthesia, positioning, portal placement, triangulation, saline irrigation, and ipsilateral and contralateral (“over-the-top”) decompression. UBE provides excellent visualization and instrument maneuverability and is indicated for various lumbar stenotic and disc herniation pathologies, including recurrent and selected complex cases. Reported advantages include reduced muscle injury and postoperative pain, shorter hospital stay, and faster recovery. Potential complications, including dural tears, epidural hematoma, and transient nerve irritation, are generally manageable with appropriate technique and training.
Pregnancy-associated spinal disorders that require surgical consideration remain uncommon, yet when they occur, they often place clinicians at the intersection of two competing priorities: preservation of maternal neurological function and protection of fetal well-being. Despite growing interest in this area, the available literature remains fragmented, largely confined to case reports, small case series, and condition-specific reviews, making it difficult to translate individual experiences into practical clinical guidance. This systematic review was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses principles to synthesize current evidence regarding surgical indications, timing of intervention, operative strategies, perioperative considerations, and maternal–fetal outcomes in pregnant patients with spinal disorders. Electronic searches identified studies addressing degenerative, neoplastic, infectious, traumatic, vascular, and pregnancy-related spinal pathologies. Thirty-three studies met the predefined eligibility criteria and were included in the qualitative synthesis. Across the available evidence, lumbar disc herniation and cauda equina syndrome represented the most frequently reported surgical conditions, although clinically significant spinal tumors, vertebral hemangiomas, epidural abscesses, spinal hematomas, and traumatic instability were also encountered. A recurring observation emerged throughout the literature: pregnancy alone was rarely a reason to defer necessary spinal intervention. Rather, neurological deterioration, spinal instability, cord compression, infection, and progressive functional decline consistently drove treatment decisions. Magnetic resonance imaging remained the preferred diagnostic modality, while multidisciplinary collaboration among spine surgeons, obstetricians, anesthesiologists, radiologists, and maternal–fetal medicine specialists was central to successful outcomes. Although the overall evidence base remains limited and heterogeneous, the collective findings support individualized management guided by neurological severity, disease-specific risk, gestational age, and fetal viability. An integrated multidisciplinary management algorithm is proposed to facilitate evidence-informed decision-making and to identify priorities for future research in this challenging field.
Background: Pedicle screw fixation is a cornerstone of modern spinal instrumentation, but its application in the cervical spine is technically demanding due to smaller pedicle dimensions and proximity to critical neurovascular structures. Objective: This systematic review and meta-analysis aims to evaluate the accuracy of freehand cervical pedicle screw placement and to quantify the incidence of critical and noncritical breaches. Material and Methods: A comprehensive electronic search was performed in PubMed, Embase, Cochrane Library, and ClinicalTrials.gov databases. Eight studies involving 1,400 pedicle screws were included. Data were extracted and analyzed using a random-effects model to account for inter-study variability. Results: The pooled pedicle screw breach rate in the cervical spine was 34% (95% confidence interval: 8%–59%). Most breaches were noncritical, with a predefined safety threshold of <2 mm. The Funnel technique demonstrated relatively lower breach rates, while the Jeanneret method showed higher rates of both overall and critical breaches. Conclusion: Freehand cervical pedicle screw placement is associated with variable accuracy and relatively high radiological breach rates. However, most breaches are noncritical and clinically well tolerated. Techniques emphasizing precise anatomical landmark identification and tactile feedback can reduce clinically significant violations. Safe placement depends on thorough anatomical understanding, surgical experience, and careful preoperative planning. Further studies are needed to correlate radiological accuracy with clinical outcomes.
