The anatomical positioning change of retroperitoneal organs in prone and lateral position: an assessment for single-prone position lateral lumbar surgery.

PURPOSE: There are reports that performing lateral lumbar interbody fusion (LLIF) in a prone, single position (single-prone LLIF) can be done safely in the prone position because the retroperitoneal organs reflect anteriorly with gravity. However, only a few study has investigated the safety of single-prone LLIF and retroperitoneal organ positioning in the prone position. We aimed to investigate the positioning of retroperitoneal organs in the prone position and evaluate the safety of single-prone LLIF surgery. METHODS: A total of 94 patients were retrospectively reviewed. The anatomical positioning of the retroperitoneal organs was evaluated by CT in the preoperative supine and intraoperative prone position. The distances from the centre line of the intervertebral body to the organs including aorta, inferior vena cava, ascending and descending colons, and bilateral kidneys were measured for the lumbar spine. An "at risk" zone was defined as distance less than 10 mm anterior from the centre line of the intervertebral body. RESULTS: Compared to supine preoperative CTs, bilateral kidneys at the L2/3 level as well as the bilateral colons at the L3/4 level had statistically significant ventral shift with prone positioning. The proportion of retroperitoneal organs within the at-risk zone ranged from 29.6 to 88.6% in the prone position. CONCLUSIONS: The retroperitoneal organs shifted ventrally with prone positioning. However, the amount of shift was not large enough to avoid risk for organ injuries and substantial proportion of patients had organs within the cage insertion corridor. Careful preoperative planning is warranted when considering single-prone LLIF.

A retrospective review of single-position prone lateral lumbar interbody fusion cases: early learning curve and perioperative outcomes.

PURPOSE: The objective of this study was to discuss our experience performing LLIF in the prone position and report our complications. METHODS: A retrospective chart review was conducted that included all patients who underwent single- or multi-level single-position pLLIF alone or as part of a concomitant procedure by the same surgeon from May 2019 to November 2022. RESULTS: A total of 155 patients and 250 levels were included in this study. Surgery was most commonly performed at the L4-L5 level (n = 100, 40%). The most common preoperative diagnosis was spondylolisthesis (n = 74, 47.7%). In the first 30 cases, 3 surgeries were aborted to an MIS TLIF. Complications included 3 unintentional ALL ruptures (n = 3/250, 1.2%), and 1 malpositioned implant impinging on the contralateral foramen requiring revision (n = 1/250, 0.4%), which all occurred within the first 30 cases. Out of 147 patients with more than 6-week follow-ups, there were 3 cases of femoral nerve palsy (n = 3/147, 2.0%). Two cases of femoral nerve palsy improved to preoperative strength by the 6th week postoperatively, while one improved to 4/5 preoperative strength by 1 year. There were no cases of bowel perforation or vascular injury. CONCLUSION: Our single-surgeon experience demonstrates the initial learning curve when adopting pLLIF. Thereafter, we experienced reproducibility in our technique and large improvements in our operative times, and complication profile. We experienced no technical complications after the 30th case. Further studies will include long-term clinical and radiographic outcomes to understand the complete utility of this approach.

Minimally invasive lateral single-position surgery for multilevel degenerative lumbar spine disease: feasibility and perioperative results in a single Latin-American spine center.

INTRODUCTION: Within advances in minimally invasive spine surgery, the implementation of lateral single position (LSP) increases efficiency while limiting complications, avoiding intraoperative repositioning and diminishing surgical time. Most literature describes one-level instrumentation of the lumbar spine; this study includes the use of LSP for multilevel degenerative disease. OBJECTIVE: The objective of the article is to analyze initial clinical results and complications in the use of LSP for multiple level instrumentation in adults with lumbar degenerative disease. METHODS: A retrospective early clinical series was performed for patients who had multiple level instrumentation in LSP between August 2019 and September 2022 at the Hospital Universitario San Ignacio in Bogota, Colombia. Inclusion criteria were patients older than 18 years with symptomatic lumbar degenerative disease, undergoing any combination of multilevel anterior lumbar interbody fusion, lateral lumbar interbody fusion (LLIF) and pedicle screw fixation. RESULTS: Forty patients with an average age of 61.3 years were included, with diagnosis of multilevel degenerative spondylotic changes. Four-, three- and two-level interventions were performed in 52.5, 35 and 12.5%, respectively. Average time per level was 68.9 min, and length of hospital stay had an average of 2.4 days, with all patients starting ambulation within the first postoperative day. CONCLUSION: Procedural time and blood loss were similar to those reported in literature. No severe lesions, postoperative infections or reinterventions took place. Although it was a small number of patients and further clinical trials are needed, LSP for multiple levels is apparently safe with adequate outcomes which may improve efficiency in the operating room.

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.

Radiographic alignment outcomes after the single-position prone transpsoas approach: a multi-institutional retrospective review of 363 cases.

OBJECTIVE: The aim of this paper was to evaluate the changes in radiographic spinopelvic parameters in a large cohort of patients undergoing the prone transpsoas approach to the lumbar spine. METHODS: A multicenter retrospective observational cohort study was performed for all patients who underwent lateral lumber interbody fusion via the single-position prone transpsoas (PTP) approach. Spinopelvic parameters from preoperative and first upright postoperative radiographs were collected, including lumbar lordosis (LL), pelvic incidence (PI), and pelvic tilt (PT). Functional indices (visual analog scale score), and patient-reported outcomes (Oswestry Disability Index) were also recorded from pre- and postoperative appointments. RESULTS: Of the 363 patients who successfully underwent the procedure, LL after fusion was 50.0° compared with 45.6° preoperatively (p < 0.001). The pelvic incidence-lumbar lordosis mismatch (PI-LL) was 10.5° preoperatively versus 2.9° postoperatively (p < 0.001). PT did not significantly change (0.2° ± 10.7°, p > 0.05). CONCLUSIONS: The PTP approach allows significant gain in lordotic augmentation, which was associated with good functional results at follow-up.

Robotic-assisted single-position lateral for multilevel circumferential lumbar interbody fusion: how I do it.

BACKGROUND: Lateral lumbar interbody fusion supplemented with insertion of pedicle screws is a surgical procedure that has gained popularity in the last years, becoming an important tool in the armamentarium of spine surgeons. In recent years, there is a trend to complete both procedures in a single position, thus avoiding flipping the patient prone to insert the pedicle screws. METHODS: We describe a step-by-step workflow of the robotic-assisted technique for multilevel lateral lumbar interbody fusion supplemented with posterior instrumentation. The surgical procedure is performed in a single lateral position. For access to L4-5 or L5-S1, an oblique abdominal incision is performed in the same position, and the desired disc space is approached through an oblique or anterior corridor in the retroperitoneal space. CONCLUSION: Robotic-assisted single-position lateral for multilevel circumferential lumbar interbody fusion is a safe and effective procedure in patients where lumbar stabilization is required. This technique provides patients with a faster recovery and low risk of complications.

Single Position ECG Detection System Based on Charge Induction.

With the growing incidence of cardiovascular disease (CVD) in recent decades, the demand for out-of-hospital real-time ECG monitoring is increasing day by day, which promotes the research and development of portable ECG monitoring equipment. At present, two main categories of ECG monitoring devices are "limb lead ECG recording devices" and "chest lead ECG recording devices", which both require at least two electrodes. The former needs to complete the detection by means of a two-hand lap joint. This will seriously affect the normal activities of users. The electrodes used by the latter also need to be kept at a certain distance, usually more than 10 cm, to ensure the accuracy of the detection results. Decreasing the electrode spacing of the existing ECG detection equipment or reducing the area required for detection will be more conducive to improving the integration of the out-of-hospital portable ECG technologies. Therefore, a single-position ECG system based on charge induction is proposed to realize ECG detection on the surface of the human body with only one electrode with a diameter of less than 2 cm. Firstly, the ECG waveform detected in a single location is simulated by analyzing the electrophysiological activities of the human heart on the human body surface with COMSOL Multiphysics 5.4 software. Then, the hardware circuit design of the system and the host computer are developed and the test is performed. Finally, experiments for static and dynamic ECG monitoring are carried out and the heart rate correlation coefficients are 0.9698 and 0.9802, respectively, which proves the reliability and data accuracy of the system.

Anatomical positional changes in the lateral lumbar interbody fusion.

INTRODUCTION: ALIFs and LLIFs are now becoming more utilized for adult spinal disease. As technologies advance, so do surgical techniques, with surgeons now modifying traditional supine-ALIF and lateral-LLIF to lateral-ALIF and prone-LLIF approaches to allow for more efficient surgeries. The objective of this study is to characterize the anatomical changes in the surgical corridor that occur with changes in patient positioning. METHODS: MRIs of ten healthy volunteers were evaluated in five positions: supine, prone with hips flexed, prone with hips extended, lateral with hips flexed, and lateral with hips extended. All lateral scans were in the left lateral decubitus position. The anatomical changes of the psoas muscles, inferior vena cava, aorta, iliac vessels were assessed with relation to fixed landmarks on the disc spaces from L1 to S1. RESULTS: The most anteriorly elongated ipsilateral to approach psoas when compared to supine was seen in lateral-flexed position (- 5.82 mm, p < 0.001), followed by lateral-extended (- 2.23 mm, p < 0.001), then prone-flexed (- 1.40 mm, p = 0.014), and finally supine and prone-extended (- 0.21 mm, p = 0.643). The most laterally extending or "thickest" psoas was seen in prone-flexed (- 1.40 mm, p = 0.004) and prone-extended (- 1.17 mm, p = 0.002). The psoas was "thinnest" in lateral-extended (2.03 mm, p < 0.001) followed by lateral-flexed (1.11 mm, p = 0.239). The contralateral psoas did not move as anteriorly as the ipsilateral. 3D volumetric analysis showed that the greatest changes in the psoas occur at its proximal and distal poles near T12-L1 and L4-S1. In lateral-flexed compared to prone-extended, the IVC moves medially to the left (p < 0.001). The aorta moves laterally to the left (p = 0.005). The venous structures appeared more full and open in the lateral positions and flattened in the supine and prone positions. The arteries remain in full calibre. CONCLUSION: The MRI anatomical evaluation shows that the psoas, and therefore lumbar plexus, and vasculature move significantly with changes in positioning. This is important for preoperative planning for proper intraoperative execution from preoperative supine MRI. Understanding that the psoas and vessels move the most anteriorly in the lateral-flexed position and to a least degree in the prone-extended is essential for safe and efficient utilization of techniques such as the traditional LLIF, traditional ALIF, prone-LLIF.

Single-position circumferential lumbar spinal fusion: an overview of terminology, concepts, rationale and the current evidence base.

PURPOSE: To provide definitions and a conceptual framework for single position surgery (SPS) applied to circumferential fusion of the lumbar spine. METHODS: Narrative literature review and experts' opinion. RESULTS: Two major limitations of lateral lumbar interbody fusion (LLIF) have been (a) a perceived need to reposition the patient to the prone position for posterior fixation, and (b) the lack of a robust solution for fusion at the L5/S1 level. Recently, two strategies for performing single-position circumferential lumbar spinal fusion have been described. The combination of anterior lumbar interbody fusion (ALIF) in the lateral decubitus position (LALIF), LLIF and percutaneous pedicle screw fixation (pPSF) in the lateral decubitus position is known as lateral single-position surgery (LSPS). Prone LLIF (PLLIF) involves transpsoas LLIF done in the prone position that is more familiar for surgeons to then implant pedicle screw fixation. This can be referred to as prone single-position surgery (PSPS). In this review, we describe the evolution of and rationale for single-position spinal surgery. Pertinent studies validating LSPS and PSPS are reviewed and future questions regarding the future of these techniques are posed. Lastly, we present an algorithm for single-position surgery that describes the utility of LALIF, LLIF and PLLIF in the treatment of patients requiring AP lumbar fusions. CONCLUSIONS: Single position surgery in circumferential fusion of the lumbar spine includes posterior fixation in association with any of the following: lateral position LLIF, prone position LLIF, lateral position ALIF, and their combination (lateral position LLIF+ALIF). Preliminary studies have validated these methods.

Anterior column reconstruction of the lumbar spine in the lateral decubitus position: anatomical and patient-related considerations for ALIF, anterior-to-psoas, and transpsoas LLIF approaches.

PURPOSE: Circumferential (AP) lumbar fusion surgery is an effective treatment for degenerative and deformity conditions of the spine. The lateral decubitus position allows for simultaneous access to the anterior and posterior aspects of the spine, enabling instrumentation of both columns without the need for patient repositioning. This paper seeks to outline the anatomical and patient-related considerations in anterior column reconstruction of the lumbar spine from L1-S1 in the lateral decubitus position. METHODS: We detail the anatomic considerations of the lateral ALIF, transpsoas, and anterior-to-psoas surgical approaches from surgeon experience and comprehensive literature review. RESULTS: Single-position AP surgery allows simultaneous access to the anterior and posterior column and may combine ALIF, LLIF, and minimally invasive posterior instrumentation techniques from L1-S1 without patient repositioning. Careful history, physical examination, and imaging review optimize safety and efficacy of lateral ALIF or LLIF surgery. An excellent understanding of patient spinal and abdominal anatomy is necessary. Each approach has relative advantages and disadvantages according to the disc level, skeletal, vascular, and psoas anatomy. CONCLUSIONS: A development of a framework to analyze these factors will result in improved patient outcomes and a reduction in complications for lateral ALIF, transpsoas, and anterior-to-psoas surgeries.

Single-position prone transpsoas fusion for the treatment of lumbar adjacent segment disease: early experience of twenty-four cases across three tertiary medical centers.

PURPOSE: Prone transpsoas fusion (PTP) is a minimally invasive technique that maximizes the benefit of lateral access interbody surgery and the prone positioning for surgically significant adjacent segment disease. The authors describe the feasibility, reproducibility and radiographic efficacy of PTP when performed for cases of lumbar ASD. METHODS: Adult patients undergoing PTP for treatment of lumbar ASD at three institutions were retrospectively enrolled. Demographic information was recorded, as was operative data such as adjacent segment levels, operative time, blood loss, laterality of approach, open versus percutaneous pedicle screw instrumentation and need for primary decompression. Radiographic measurements including segmental and global lumbar lordosis, pelvic incidence, pelvic tilt, sacral slope and sagittal vertical axis were recorded both pre- and immediately post-operatively. RESULTS: Twenty-four patients met criteria for inclusion. Average age was 60.4 ± 10.4 years and average BMI was 31.6 ± 5.0 kg/m2. Total operative time was 204.7 ± 83.3 min with blood loss of 187.9 ± 211 mL. Twenty-one patients had pedicle screw instrumentation exchanged percutaneously and 3 patients had open pedicle screw exchange. Two patients suffered pulmonary embolism that was treated medically with no long-term sequelae. One patient had transient lumbar radicular pain and all patients were discharged home with an average length of stay of 3.0 days (range 1-6). Radiographically, global lumbar lordosis improved by an average of 10.3 ± 9.0 degrees, segmental lordosis by 10.1 ± 13.3 degrees and sagittal vertical axis by 3.2 ± 3.2 cm. CONCLUSION: Single-position prone transpsoas lumbar interbody fusion is a clinically reproducible minimally invasive technique that can effectively treat lumbar adjacent segment disease.

Surgical fixation of pathologic and traumatic spinal fractures using single position surgery technique in lateral decubitus position.

STUDY DESIGN: Retrospective Case Series. OBJECTIVES: This study aims to determine complications, readmission, and revision surgery rates in patients undergoing single position surgery (SPS) for surgical treatment of traumatic and pathologic thoracolumbar fractures. METHODS: A multi-center review of patients who underwent SPS in the lateral decubitus position (LSPS) for surgical management of traumatic or pathologic thoracolumbar fractures between January 2016 and May 2020 was conducted. Operative time, estimated blood loss (EBL), intraoperative complications, postoperative complications, readmissions, and revision surgeries were collected. RESULTS: A total of 12 patients with a mean age of 45 years (66.67% male) were included. The majority of patients underwent operative treatment for acute thoracolumbar trauma (66.67%) with a mean injury severity score (ISS) of 16.71. Mean operative time was 175.5 min, mean EBL of 816.67 cc. Five patients experienced a complication, two of which required revision surgery for additional decompression during the initial admission. All ambulatory patients were mobilized on postoperative day 1. The mean hospital length of stay (LOS) was 9.67 days. CONCLUSION: The results of this case series supports LSPS as a feasible alternative to the traditional combined anterior-posterior approach for surgical treatment of pathologic and thoracolumbar fractures. These results are similar to reductions in operative time, EBL, and LOS seen in the elective spine literature with LSPS. LEVEL OF EVIDENCE: IV.

Setting for single position surgery: survey from expert spinal surgeons.

PURPOSE: To describe a comprehensive setting of the different alternatives for performing a single position fusion surgery based on the opinion of leading surgeons in the field. METHODS: Between April and May of 2021, a specifically designed two round survey was distributed by mail to a group of leaders in the field of Single Position Surgery (SPS). The questionnaire included a variety of domains which were focused on highlighting tips and recommendations regarding improving the efficiency of the performance of SPS. This includes operation room setting, positioning, use of technology, approach, retractors specific details, intraoperative neuromonitoring and tips for inserting percutaneous pedicle screws in the lateral position. It asked questions focused on Lateral Single Position Surgery (LSPS), Lateral ALIF (LA) and Prone Lateral Surgery (PLS). Strong agreement was defined as an agreement of more than 80% of surgeons for each specific question. The number of surgeries performed in SPS by each surgeon was used as an indirect element to aid in exhibiting the expertise of the surgeons being surveyed. RESULTS: Twenty-four surgeons completed both rounds of the questionnaire. Moderate or strong agreement was found for more than 50% of the items. A definition for Single Position Surgery and a step-by-step recommendation workflow was built to create a better understanding of surgeons who are starting the learning curve in this technique. CONCLUSION: A recommendation of the setting for performing single position fusion surgery procedure (LSPS, LA and PLS) was developed based on a survey of leaders in the field.

Fluoroscopy-based percutaneous posterior screw placement in the lateral position using the tunnel view technique: technical note.

PURPOSE: Lumbar fusion using lateral single position surgery (LSPS) gained popularity during the last few years. While prone percutaneous pedicle screw placement is well described, placing percutaneous pedicle screws with the patient in the lateral position is considered the most complicated part of LSPS. In this article we describe the fluoroscopy navigated technique for lateral percutaneous screw placement using the tunnel view technique. METHODS: The radiologic background and principles of the tunnel view technique are described. In addition, the special positioning of the patient, the C-arm and the surgical technique is discussed in detail. RESULTS: This technique is used as the standard for percutaneous screw placement in the prone or lateral positions in our department since 2017. Since the introduction of this technique we have had 0% reoperation rate for symptomatic malpositioned pedicle screws. CONCLUSION: The tunnel view technique simplifies pedicle screw placement while allowing for permanent observation of pedicle walls and the superior joint surface during placement of the Jamshidi needle. It also allows for confirmation of intrapedicular position of the screw after its implantation. This technique is safe and feasible in our clinical experience.

Postoperative spinal alignment comparison of lateral versus supine patient position L5-S1 anterior lumbar interbody fusion.

PURPOSE: Over the past decade, alternative patient positions for the treatment of the anterior lumbar spine have been explored in an effort to maximize the benefits of direct anterior column access while minimizing the inefficiencies of single or multiple intraoperative patient repositionings. The lateral technique allows for access from L1 to L5 through a retroperitoneal, muscle-splitting, transpsoas approach with placement of a large intervertebral spacer than can reliably improve segmental lordosis, though its inability to be used at L5-S1 limits its overall adoption, as L5-S1 is one of the most common levels treated and where high levels of lordosis are optimal. Recent developments in instrumentation and techniques for lateral-position treatment of the L5-S1 level with a modified anterior lumbar interbody fusion (ALIF) approach have expanded the lateral position to L5-S1, though the positional effect on L5-S1 lordosis is heretofore unreported. The purpose of this study was to compare local and regional alignment differences between ALIFs performed with the patient in the lateral (L-ALIF) versus supine position (S-ALIF). METHODS: Retrospective, multi-center data and radiographs were collected from 476 consecutive patients who underwent L5-S1 L-ALIF (n = 316) or S-ALIF (n = 160) for degenerative lumbar conditions. Patients treated at L4-5 and above with other single-position interbody fusion and posterior fixation techniques were included in the analysis. Baseline patient characteristics were similar between the groups, though L-ALIF patients were slightly older (58 vs. 54 years), with a greater preoperative mean L5-S1 disk height (7.8 vs. 5.8 mm), and with less preoperative slip (6.6 vs. 8.5 mm), respectively. 262 patients were treated with only L-ALIF or S-ALIF at L5-S1 while the remaining 214 patients were treated with either L-ALIF or S-ALIF at L5-S1 along with fusions at other thoracolumbar levels. Lumbar lordosis (LL), L5-S1 segmental lordosis, L5-S1 disk space height, and slip reduction in L5-S1 spondylolisthesis were measured on preoperative and postoperative lateral X-ray images. LL was only compared between single-level ALIFs, given the variability of other procedures performed at the levels above L5-S1. RESULTS: Mean pre- to postoperative L5-S1 segmental lordosis improved 39% (6.6°) and 31% (4.9°) in the L-ALIF and S-ALIF groups, respectively (p = 0.063). Mean L5-S1 disk height increased by 6.5 mm (89%) in the L-ALIF and 6.4 mm (110%) in the S-ALIF cohorts, (p = 0.650). Spondylolisthesis, in those patients with a preoperative slip, average reduction in the L-ALIF group was 1.5 mm and 2.2 mm in the S-ALIF group (p = 0.175). In patients treated only at L5-S1 with ALIF, mean segmental alignment improved significantly more in the L-ALIF compared to the S-ALIF cohort (7.8 vs. 5.4°, p = 0.035), while lumbar lordosis increased 4.1° and 3.6° in the respective groups (p = 0.648). CONCLUSION: Use of the lateral patient position for L5-S1 ALIF, compared to traditional supine L5-S1 ALIF, resulted in at least equivalent alignment and radiographic outcomes, with significantly greater improvement in segmental lordosis in patients treated only at L5-S1. These data, from the largest lateral ALIF dataset reported to date, suggest that-radiographically-the lateral patient position can be considered as an alternative to traditional ALIF positional techniques.

Lateral decubitus single position anterior-posterior (AP) fusion shows equivalent results to minimally invasive transforaminal lumbar interbody fusion at one-year follow-up.

PURPOSE: This study compares perioperative and 1-year outcomes of lateral decubitus single position circumferential fusion (L-SPS) versus minimally invasive transforaminal lumbar interbody fusion (MIS TLIF) for degenerative pathologies. METHODS: Multicenter retrospective chart review of patients undergoing AP fusion with L-SPS or MIS TLIF. Demographics and clinical and radiographic outcomes were compared using independent samples t tests and chi-squared analyses with significance set at p < 0.05. RESULTS: A total of 445 patients were included: 353 L-SPS, 92 MIS TLIF. The L-SPS cohort was significantly older with fewer diabetics and more levels fused. The L-SPS cohort had significantly shorter operative time, blood loss, radiation dosage, and length of stay compared to MIS TLIF. 1-year follow-up showed that the L-SPS cohort had higher rates of fusion (97.87% vs. 81.11%; p = 0.006) and lower rates of subsidence (6.38% vs. 38.46%; p < 0.001) compared with MIS TLIF. There were significantly fewer returns to the OR within 1 year for early mechanical failures with L-SPS (0.0% vs. 5.4%; p < 0.001). 1-year radiographic outcomes revealed that the L-SPS cohort had a greater LL (56.6 ± 12.5 vs. 51.1 ± 15.9; p = 0.004), smaller PI-LL mismatch (0.2 ± 13.0 vs. 5.5 ± 10.5; p = 0.004). There were no significant differences in amount of change in VAS scores between cohorts. Similar results were seen after propensity-matched analysis and sub-analysis of cases including L5-S1. CONCLUSIONS: L-SPS improves perioperative outcomes and does not compromise clinical or radiographic results at 1-year follow-up compared with MIS TLIF. There may be decreased rates of early mechanical failure with L-SPS.

Spinal exposure for anterior lumbar interbody fusion (ALIF) in the lateral decubitus position: anatomical and technical considerations.

PURPOSE: Single position surgery has demonstrated to reduce hospital length of stay, operative times, blood loss, postoperative pain, ileus, and complications. ALIF and LLIF surgeries offer advantages of placing large interbody devices under direct compression and can be performed by a minimally invasive approach in the lateral position. Furthermore, simultaneous access to the anterior and posterior column is possible in the lateral position without the need for patient repositioning. The purpose of this study is to outline the anatomical and technical considerations for performing anterior lumbar interbody fusion (ALIF) in the lateral decubitus position. METHODS: Surgical technique and technical considerations for reconstruction of the anterior column in the lateral position by ALIF at the L4-5 and L5-S1 levels. RESULTS: Topics outlined in this review include: Operating room layout and patient positioning; surgical anatomy and approach; vessel mobilization and retractor placement for L4-5 and L5-S1 lateral ALIF exposure, in addition to comparative technique of disc space preparation, trialing and implant placement compared to the supine ALIF procedure. CONCLUSIONS: Anterior exposure performed in the lateral decubitus position allows safe-, minimally invasive access and implant placement in ALIF. The approach requires less peritoneal and vessel retraction than in a supine position, in addition to allowing simultaneous access to the anterior and posterior columns when performing 360° Anterior-Posterior fusion.

Complete transperitoneal laparoscopic nephroureterectomy in a single position for upper urinary tract urothelial carcinoma and comparative outcomes.

BACKGROUND: To describe the techniques and outcomes of complete transperitoneal laparoscopic nephroureterectomy (CTLNU) for upper urinary tract urothelial carcinoma (UTUC) in a single position. MATERIALS AND METHODS: Those patients with localized UTUC were included, among which 50 cases had CTLNU while 48 cases had laparoscopic nephroureterectomy with open bladder cuff excision (LNOBE). The clinical data were collected and analyzed retrospectively. RESULTS: All 98 patients underwent successful procedures of radical nephroureterectomy without transferring into open surgery. No significant difference was found among baseline clinical characteristics. Compared with the LNOBE group, the CTLNU group had a shorter operative time (98.5±40.3 min vs. 132.4±60.2 min), less blood loss (60.4±20.3 ml vs. 150.6±50.2 ml), shorter length of hospital stay (5.3±2.2 days vs. 8.1±2.3 days), and shorter incision (6.3±1.2 cm vs. 11.5±3.2 cm). The disease-related outcomes such as pathological stage, tumor grade, and recurrence rate were similar between the two groups. CONCLUSIONS: The CTLNU in a single position had advantages of shorter operation time, less blood loss, and shorter incision length. This surgical technique is a more minimally invasive, simplified, and effective way to perform the radical nephroureterectomy.

Applied anatomy and surgical technique of the lateral single-position L5-S1 fusion.

The latest development in the anterior lumbar interbody fusion (ALIF) procedure is its application in the lateral position to allow for simultaneous posterior percutaneous screw placement. The technical details of the lateral ALIF technique have not yet been described. To describe the surgical anatomy relevant to the lateral ALIF approach we performed a comprehensive anatomical study. In addition, the preoperative imaging, patient positioning, planning of the skin incision, positioning of the C-arm, surgical approach, and surgical technique are discussed in detail. The technique described led to the successful use of the lateral ALIF technique in our clinical cases. No lateral ALIF procedure needed to be aborted during these cases. Our present work gives detailed anatomical background and technical details for the lateral ALIF approach. This teaching article can provide readers with sufficient technical and anatomical knowledge to assist them in performing their first lateral ALIF procedure.

Simultaneous single-position lateral interbody fusion and percutaneous pedicle screw fixation using O-arm-based navigation reduces the occupancy time of the operating room.

PURPOSE: Lateral interbody fusion and posterior percutaneous pedicle screw (LIF-PPS) fixation has been performed in two-stage positioning. The aim of this study was to investigate the surgical outcomes of simultaneous single-position LIF-PPS fixation using O-arm-based navigation. METHODS: Overall, 102 consecutive subjects underwent indirect decompression surgery for spondylolisthesis with LIF-PPS fixation. Fifty-one subjects underwent surgery with repositioning, and 51 in the right lateral decubitus position. We compared these two groups in terms of the surgery time, occupancy time in the operating room, intraoperative blood loss, Japanese Orthopaedic Association (JOA) score, local lordosis acquisition in postoperative radiographs, and accuracy of screw insertion using postoperative CT scans. RESULTS: In the single-position group, surgery time, occupancy time of the operating room, and estimated blood loss were 93.3 ± 19.3 min (vs. the repositioning group: 121.0 ± 37.1 min; p < 0.001), 176.3 ± 36.4 min (vs. 272.4 ± 42.7 min; p < 0.001), and 93.4 ± 78.8 ml (vs. 40.9 ± 28.7 ml; p < 0.001), respectively. The JOA scores (pre-/postoperative) were 15.1 ± 3.0/24.4 ± 2.8 (p < 0.001) for the single-position group and 15.1 ± 4.0/24.8 ± 3.0 (p < 0.001) for the repositioning group. The rate of misplacement was 1.8% versus 4.0%, respectively (p = 0.267), and the lordosis acquisition was 4.2° ± 4.1° versus 4.4° ± 3.2°, respectively (p = 0.516). CONCLUSIONS: Single-position surgery exhibited comparable clinical outcomes and local lordosis acquisition with conventional repositioning LIF-PPS fixation. This single-position minimally invasive technique reduces the occupancy time of the operating room and workforce requirements. These slides can be retrieved under Electronic Supplementary Material.