L3 Level Research Articles

Evaluation of the association between osteoporotic vertebral compression fractures and psoas major/paraspinal muscle mass and ADC measured on MRI.

Evaluate magnetic resonance imaging factors associated with osteoporotic vertebral compression fractures. We retrospectively reviewed 457 patients' records. Age, sex, and body mass index were recorded. Two blinded readers measured psoas major and paraspinal muscle areas at the L3 vertebral body level on transverse T2-weighted magnetic resonance images and the mean apparent diffusion coefficient values of the non-fractured vertebrae from Th12 to L5. Inter-reader reliability for continuous variables was assessed by intraclass correlation coefficients. We evaluated 210 patients (103 [49.0%] men). The osteoporotic vertebral compression fractures group was older and had lower BMI and smaller psoas major and paraspinal muscle areas than the group without vertebral compression fractures (p < 0.001). The mean apparent diffusion coefficient was weakly correlated with paraspinal muscle area in the osteoporotic vertebral compression fractures group. The intraclass correlation coefficient value was 0.83, and the intraclass correlation coefficients of the psoas major and paraspinal muscles were 0.94 and 0.97, respectively. Multivariate analysis revealed that decreased psoas major and paraspinal muscle areas and increased mean apparent diffusion coefficient values were significantly associated with the presence of osteoporotic vertebral compression fractures (all p < 0.05). Psoas major and paraspinal muscle areas showed relatively high predictive accuracy (57%, 61%). Psoas major and paraspinal muscle areas at the L3 level and the mean apparent diffusion coefficient value of non-fractured vertebrae from the Th12 to L5 level were associated with osteoporotic vertebral compression fractures. This may contribute to detecting the potential risk of healthy individuals developing osteoporotic vertebral compression fractures.

Unilateral Biportal Endoscopic Laminectomy-Bilateral Decompression Using a Monoportal Scope and Bipolar Coagulator for Lumbar Spinal Stenosis: A Technical Report.

The purpose of this study was to introduce the application of a monoportal scope and bipolar coagulator used in full-endoscopic spine surgery (FESS) for unilateral biportal endoscopy-unilateral laminectomy bilateral decompression (UBE-ULBD) in those with central stenosis. A 68-year-old man who presented with cauda equina symptoms underwent UBE-ULBD to improve his central stenosis at the L2/3 level. In this technique, a FESS scope was attached to a camera portal in place of a common arthroscope. A decompression tool was subsequently inserted through the working portal, and the lower border of the vertebral lamina and the lower border of the contralateral lamina were resected. Additionally, the superior border of the L3 level was thinned using a high-speed drill, and the ligament flavum was excised. The operation time was 70 minutes, and his symptoms improved. The patient was discharged from the hospital four days postoperatively. We found three advantages of using a FESS scope and bipolar coagulator, including the ability to 1) stabilize the camera via placement of the sleeve against the bone, 2) minimize the wounded area by irrigating saline on the side of the scope, and 3) provide bipolar tissue hemostasis in an isolated area around the nerves. Therefore, among the UBE techniques, we believe that assisted full-endoscopic spine surgery (AFESS) is a viable option to offer a more minimally invasive surgery for patients with stenosis.

The Comparison between Herniated and Non-Herniated Disc Levels Regarding Intervertebral Disc Space Height and Disc Degeneration, A Magnetic Resonance Study.

The main purpose of this study was to evaluate the intervertebral disc height and intervertebral disc degeneration between the normal group and the group with disc herniation at the level of the L4-L5 intervertebral disc by MRI using the Pfirrmann grading system. 385 patients were included in this study. MRI images were reevaluated and intervertebral disc heights were measured from the anterior, middle and posterior segments. Researchers divided disc pathologies into two groups. In the non-herniated group; normal or bulging ones; in the herniated group, they included those with protrusion or extrusion. 385 lumbar MRI examinations meeting the study criteria were included in study. There were 56.9% (219/385) females and 43.1% (166/385) males in the study. For the whole patients in the study group, the intervertebral disc height values at the L4-5 level were measured as 12.34 mm, 11.58 mm, and 7.60 mm in the anterior, middle, and posterior localizations, respectively. At the L4-5 level, the height of the disc distances in the herniated group was lower than in the normal group. The Pfirrman score was found to be higher in the herniated group in terms of disc degeneration compared to the normal group.

A case report: Unilateral biportal endoscopic revision for adjacent segmental disease: Case presentations and literature review.

Biportal endoscopic revision surgery for adjacent segmental disease (ASD) after lumbar arthrodesis is seldomly reported. Herein, we present 3 cases of ASD with radiculopathy wherein satisfactory results were obtained using unilateral biportal endoscopic (UBE) decompression. Case 1 was of a 56-year-old male who presented with a chief complaint of Intermittent claudication since 2-year. Case 2 involved a 78-year-old female who was admitted to the hospital with a chief complaint of radiating pain and weakness in the left leg for at least 1 year. Case 3 was a 67-year-old woman who visited our hospital because of radiating leg pain for 5 months. All the cases had a history of L4 to L5 lumbar interbody fusion surgery. Computed tomography and magnetic resonance imaging showed the spinal epidural lipomatosis at the L3 to L4 level in case 1, the up-migrated lumbar disc herniation at L3 to L4 level in case 2 and unilateral foraminal stenosis at the L5 to S1 level in case 3. Under UBE guidance, the ipsilateral approach was used to treat adjacent lumbar stenosis caused by spinal epidural lipomatosis. The contralateral approach was used to remove the up-migrated herniated disc. The paraspinal approach was applied to decompress the foraminal stenosis. Postoperative parameters were improved clinically, and nerve roots were decompressed radiologically. No complications were developed. UBE revision surgery showed a favorable clinical and radiological result without complications and may be a safe and effective alternative technique for ASD.

OR15-02 Changes In Liver Fat Content By CT 1 Year After Sleeve Gastrectomy In Adolescents With Severe Obesity

Abstract Disclosure: A.P. López López: None. S. Tuli: None. M. Lauze: None. I. Becetti: None. C.C. Pedreira: None. F.A. Huber: None. E. Omeroglu: None. M. Misra: None. V. Singhal: None. M.A. Bredella: None. Introduction: Obesity is associated with non-alcoholic fatty liver disease (NAFLD). Sleeve gastrectomy (SG), the most commonly used metabolic and bariatric surgery, is an effective means of weight loss and has been shown to improve NAFLD in adults but data regarding the efficacy of SG in early stages of NAFLD where steatosis is the only pathology is evolving. We aim to assess the impact of SG on hepatic fat content, one year after SG in youth with severe obesity. Objective: To (i) identify changes in liver fat content using attenuation measurements on non-contrast CT [liver/spleen (L:S) ratio] in youth with obesity before and 12 months after sleeve gastrectomy (SG) compared with non-surgical controls with obesity (NS) and (ii) associations of changes in L:S with changes in body composition. Methods: 52 participants 13-25 years old with obesity were followed for 12 months. 25 subjects had SG (84% female), and 27 were NS (70% female). Non-contrast CT of the abdomen was performed for attenuation measurements of liver and spleen in Hounsfield Units (HU), expressed as L:S ratio. A lower L:S ratio indicates higher liver fat. A single-slice MRI of the abdomen at the level of L4 was performed to assess subcutaneous and visceral adipose tissue (SAT and VAT) cross sectional areas (cm2). Results: Mean age did not differ across groups. Body mass index (BMI) at baseline trended higher in SG vs. NS [44.18 (41.33, 53.72) vs. 42.16 (38.65, 46.96) kg/m2, (p=0.073)], and the mean 1-year decrease in BMI was greater in SG vs. NS (-12.48±0.83 vs. -0.21±0.52 kg/m2, p&amp;lt;0.0001). VAT decreased in SG but increased in NS [-50.77 cm2 (-61.26, -34.09) vs. 13.55 cm2 (-10.27, 34.78), p&amp;lt;0.0001], over 1 year. There was a within group increase in the L:S ratio in SG (0.13± 0.05, p= 0.014) but not NS over 1 year, with a trend for a difference between groups (p=0.055). All SG participants with an L:S ratio &amp;lt;0.9 (threshold for the diagnosis of NAFLD) before surgery had a ratio of &amp;gt;1.0 a year after surgery, consistent with resolution of NAFLD. Within SG, the 1-year change in L:S ratio was negatively associated with 1-year change in visceral fat (ρ=-0.52 p=0.017). Conclusions: Hepatic fat content as assessed by non-contrast CT improved after SG over 1-year in youth with obesity with resolution of NAFLD in all subjects. This was associated with improvements in body composition, especially visceral adiposity. Presentation: Friday, June 16, 2023

THU065 Evaluation Of Sarcopenia And Bone Health In Patients With Acromegaly

Abstract Disclosure: I. Eroglu: None. B. Gonul İremli: None. A. Erkoc: None. I. Idilman: None. D. Yuce: None. E. C. Kutukcu: None. D. Akata: None. T. Erbas: None. Background: Although many complications related to high GH exposure develop in patients with acromegaly, musculoskeletal complications are among the most important complications that reduce the quality of life of patients. However, the effects of acromegaly on muscle and bone have not been adequately researched and are still not entirely understood. We aimed to investigate muscle and bone quality in acromegalic patients in this cross-sectional, case-controlled study. Methods: The study consisted of thirty-two (15F/17M) acromegalic patients (n=15 active acromegaly - AA and n=17 controlled acromegaly - CA) and 19 healthy controls (C). Dual energy X-ray absorptiometry (DXA) was used to determine body composition, appendicular skeletal muscle mass (ASM), relative skeletal muscle index (RSMI), and bone mineral density (BMD). The handgrip strength (HGS) and quadriceps muscle strength were measured by hand dynamometer. Magnetic resonans imaging at the L3 level was used to measure total abdominal muscle area (TAMA, cm2) and vertebral fat ratio (VFR). HGS adjusted by ASM (HGS/ASM) was used to define skeletal muscle quality (SMQ). SMQ was regarded “normal” when the HGS/ASM ratio was &amp;gt;1.53, and “weak” when the ratio was ≤1.36 in males and ≤1.35 in women. The SMQ of those with HGS/ASM levels between these ranges was considered “low”. Results: Age, gender, and BMI were similar between groups. The GH and IGF-1 levels in AA was greater than in CA, and C (p&amp;lt;0.001 for all). While lean tissue was higher in AA than CA and C (p=0.038 and p=0.041, resp.), body fat ratio was lower in AA than CA and C (p=0.04 and p=0.042 resp.). ASM, RSMI, TAMA, HGS and quadriceps strength were similar between groups. Median (IQR) HGS/ASM were 1.67 (1.15-1.9) in AA, 1.57 (1.36-1.79) in CA and 1.77 (1.67-1.93) in C. This difference was found to be significant between CA and C (p=0.008). According to skelatal muscle quality, 94.7% of the individuals in the C group were of normal SMQ, while this rate was 60% in the AA and 52.9% in CA. The ratio of those with low/weak SMQ was higher in the AA and CA compared to C (p=0.012 and p=0.013, resp.). Total and vertebra BMD were similar across groups. Pelvic BMD in CA was lower than C (p=0.02). VFR was higher in CA (56.5%) than in AA (43.75%) and C (42.6%) (p=0.04 and p=0.001 resp.). Conclusion: We showed for the first time that patients with acromegaly had lower muscle quality and pelvic BMD, while patients with controlled acromegaly had higher vertebral fat ratio. Even though lean tissue increased in AA patients, regional muscle distributions (ASM and TAMA) were shown to be similar. The increased muscle mass in acromegaly patients is not expressed as muscular strength, and muscle quality is low in these patients. The high vertebral fat ratio seen in patients with CA may be a result of ectopic adiposity with disease control, as well as the reason for the increased frequency of vertebral fractures seen in patients with acromegaly. Presentation: Thursday, June 15, 2023

Ultrasound-guided anterior quadratus lumborum block at the L2 level for postsurgical analgesia in patients undergoing laparoscopic gynaecological surgery: a single-centre, randomised, double-blinded trial at a university-affiliated hospital in China

ObjectiveThis study aimed to investigate the analgesic effect of an ultrasound-guided anterior quadratus lumborum block (QLB) at the L2 level on postoperative pain after laparoscopic gynaecological surgery.DesignProspective single-centre randomised double-blind...

The consistency of skeletal muscle mass measured by CT at L1 and L3 levels and the correlation of skeletal muscle density at L1 level with prognosis in dialysis patients

Objective: To investigate the consistency of skeletal muscle mass by CT at 1st lumbar vertebrae (L1) and 3rd lumbar vertebrae (L3) levels and the correlation of skeletal muscle density (SMD) at L1 level with prognosis in dialysis patients. Methods: A total of 1 020 patients who underwent initial dialysis and had CT examination data in four centers (Zhongda Hospital Affiliated to Southeast University, the Third Affiliated Hospital of Soochow University, Taizhou People's Hospital Affiliated to Nanjing Medical University and the Affiliated Hospital of Yangzhou University) from January 2014 to December 2019 were retrospectively collected. The skeletal muscle index (SMI) and SMD at L1 and L3 CT images were measured and calculated in patients with both L1 and L3 level CT images. The consistency of SMI and SMD at L1 and L3 levels was analyzed, and the cut-off value of SMI and SMD at L1 level for predicting all-cause mortality and their correlation with the prognosis of dialysis patients were studied. Cox regression model was used to analyze the risk factors for all-cause death and cardiac death. Results: A total of 383 patients had both L1 and L3 level images, including 233 males and 150 females. The average SMD value of 16 samples (4.2%) exceeded the 95% consistency limit range (-8.71 to 7.75 HU), and the average SMI value of 15 samples (3.9%) exceeded the 95% consistency limit range (-20.45 to 9.53 HU). The optimal cut-off value of SMD at L1 level for predicting all-cause mortality was 36.46 HU and the area under curve (AUC) of receiver operating characteristic (ROC) curve was 0.658 (95%CI: 0.596-0.721, P<0.001), with the sensitivity and specificity of 83.8% and 57.5%, respectively. SMI at L1 level was not significantly associated with all-cause mortality (P=0.299). Multivariate Cox regression analysis showed that low SMD at L1 level was associated with all-cause mortality (HR=2.861, 95%CI: 1.576-5.193, P=0.001) and cardiac death (HR=3.771, 95%CI:1.462-9.724, P=0.006). Conclusions: SMD at L1 levelis consistent with SMD at L3 level and can be used to evaluate muscle mass. Low SMD is a risk factor for mortality in dialysis patients.

Long-term changes in psoas muscle mass after lobectomy and segmentectomy for early-stage lung cancer.

Segmentectomy is considered a less invasive procedure than lobectomy for patients with non-small cell lung cancer (NSCLC); however, little is known about the physiological mechanism underlying the lower invasiveness of segmentectomy. This study is aimed to compare the differences in the long-term changes in the psoas muscle mass after segmentectomy and lobectomy in patients with NSCLC. Overall 315 recurrence-free patients who underwent segmentectomy (n=93) or lobectomy (n=222) for clinical stage 0-I NSCLC between January 2016 and December 2018 and underwent computed tomography during the entire period of 6months≤postoperative year (POY) 0.5<12months, 12months≤POY 1<24months, 24months≤POY 2<36months, and 36months≤POY 3<48months were included. Bilateral psoas muscle area (PMA) at the L3 level was measured using each cross-sectional computed tomography scan. Differences between the segmentectomy and lobectomy groups in the mean change of postoperative PMA from the preoperative period were analysed using Student's t-test and mixed analysis of variance. Multivariableanalysis was performed to identify the risk factors for PMA loss on POY 3 using logistic regression analysis. The lobectomy group had a significantly larger PMA change than the segmentectomy group during each postoperative period (P<0.001). Mixed analysis of variance revealed that the mean PMA change was significantly smaller in the segmentectomy group than in the lobectomy group during the observation period (P<0.001). The mean change in the PMA was significantly larger from POY1 (-2.5%) to POY2 (-3.9%) and POY3 (-4.7%) in the lobectomy group (P=0.003 and P<0.001). However, PMA remained unchanged during the postoperative observation period in the segmentectomy group. In the multivariable analysis, the risk factors for PMA change ≤-3.3% (cut-off: mean change of PMA) at POY3 included lobectomy [odds ratio (OR), 3.32; 95% confidence interval (CI), 1.90-5.82; P<0.001], male sex (OR, 1.92; 95% CI, 1.02-3.62; P=0.044) and open thoracotomy (OR, 1.84; 95% CI, 1.11-3.05; P=0.017). After propensity score matching, the mean change in PMA was smaller in the segmentectomy group (n=75) than in the lobectomy group (n=75) during the postoperative observation period (P<0.001). Psoas muscle mass was better maintained during the postoperative period by segmentectomy than by lobectomy. Psoas muscle mass reduction progressed over a long postoperative period after lobectomy. Segmentectomy via complete video-assisted thoracic surgery is associated with a lower likelihood of sarcopenia progression.

The anesthetic efficacy of ultrasound-guided lumbar plexus combined with quadratus lumborum block with Shamrock approach in total hip arthroplasty: study protocol for a randomized controlled trial

IntroductionThe lumbar plexus originates from multiple segments of the spinal cord. Both single-level lumbar plexus block (LPB) and transmuscular quadratus lumborum block (TQLB) are commonly used to provide analgesia for the patients undergoing total hip arthroplasty (THA). However, neither of them can completely cover the lumbar plexus. Multiple-level LPB is also not recommended since this expert technique involves more potential risks. To achieve a better anesthetic effect and avoid risks, we propose to combine ultrasound-guided LPB with TQLB with Shamrock approach. We aim to assess the anesthetic efficacy of this combination technique and expect it will be an ideal alternative for conventional LPBs in THA.Methods and analysisIn this prospective randomized controlled trial, 84 patients schedule for THA will be enrolled. The patients will be randomly assigned at a 1:1:1 ratio to receive LPB at L3 level (P group), T12 paravertebral block combined with LPB at L3 and L4 levels (TP group), or LPB combined with TQLB at L3 level (PQ group). Each method will be evaluated in terms of the successful rate of sensory blockade, postoperative pain, performance time of block, requirement for intraoperative sufentanil, cumulative doses of intraoperative vasoactive medications, and adverse events.Ethics and disseminationThe study protocol has been approved by the institutional review board (IRB) at Shanghai Jiao Tong University Affiliated Sixth People’s Hospital, China (No.2020–031). The results will be disseminated in a peer-reviewed journal and the ClinicalTrials.gov registry.Trial registrationClinicalTrials.gov, NCT04266236. Registered on 10 February 2020. ClinicalTrials.gov PRS: Record Summary NCT04266236.

Computed tomography-determined skeletal muscle density predicts 3-year mortality in initial-dialysis patients in China.

Skeletal muscle mass and quality assessed by computed tomography (CT) images of the third lumbar vertebra (L3) level have been established as risk factors for poor clinical outcomes in several illnesses, but the relevance for dialysis patients is unclear. A few studies have suggested a correlation between CT-determined skeletal muscle mass and quality at the first lumbar vertebra (L1) level and adverse outcomes. Generally, chest CT does not reach beyond L1. We aimed to determine whether opportunistic CT scan (chest CT)-determined skeletal muscle mass and quality at L1 are associated with mortality in initial-dialysis patients. This 3-year multicentric retrospective study included initial-dialysis patients from four centres between 2014 and 2017 in China. Unenhanced CT images of the L1 and L3 levels were obtained to assess skeletal muscle mass [by skeletal muscle index, (SMI), cm2 /m2 ] and quality [by skeletal muscle density (SMD), HU]. Skeletal muscle measures at L1 were compared with those at L3. The sex-specific optimal cutoff values of L1 SMI and L1 SMD were determined in relation to all-cause mortality. The outcomes were all-cause death and cardiac death. Cox regression models were applied to investigate the risk factors for death. A total of 485 patients were enrolled, of whom 257 had both L1 and L3 images. Pearson's correlation coefficient between L1 and L3 SMI was 0.84 (P<0.001), and that between L1 and L3 SMD was 0.90 (P<0.001). No significant association between L1 SMI and mortality was observed (P>0.05). Low L1 SMD (n=280, 57.73%) was diagnosed based on the optimal cutoff value (<39.56 HU for males and <33.06 HU for females). Multivariate regression analysis revealed that the low L1 SMD group had higher risks of all-cause death (hazard ratio 1.80; 95% confidence interval 1.05-3.11, P=0.034) and cardiac death (hazard ratio 3.74; 95% confidence interval 1.43-9.79, P=0.007). In initial-dialysis patients, there is high agreement between the L1 and L3 measures for SMI and SMD. Low SMD measured at L1, but not low SMI, is an independent predictor of both all-cause death and cardiac death.

Surgical Anatomy of Transversus Abdominis Muscle for Transversus Abdominis Release: A CT-Based Study in Three Patient Groups.

The anatomy of the transversus abdominis muscle and its aponeurosis is important in transversus abdominis release surgery. We studied the CT anatomy of the transversus abdominis muscle medial to the linea semilunaris at different levels in the abdomen and measured the thickness of this muscle. In this retrospective study, we analysed 150 abdominal computed tomography at L1, L3, and L5 vertebral levels corresponding to subxiphoid, umbilical, and suprapubic regions, respectively. The patients were divided into three groups based on age and sex: women aged 15-20 years (nulliparous), women aged 30-60 years (multiparous), and men aged 15-60 years, with each group having 50 patients. We compared the thickness of the TA muscle at the L1 level between men and women and between nulliparous and multiparous women. Transversus abdominis muscle was consistently present medial to the linea semilunaris at L1 vertebral level in the subxiphoid region (150/150). At the L3 vertebral level in the mid-abdomen, only eight patients had the transversus abdominis muscle there (8/150, 5%). At the L5 vertebral level in the suprapubic region, no patient had the transversus abdominis muscle medial to the linea semilunaris. The mean thickness of the transversus abdominis muscle at the L1 level was 3.4 mm, and at the L3 level, it was 1.6 mm. There was no statistically significant difference in the transversus abdominis muscle thickness between the men and women; however, a significant difference was found between the nulliparous and multiparous women, with thinner TA muscle in later. There is good transversus abdominis muscle bulk medial to the linea semilunaris for doing transversus abdominis muscle division in the upper abdomen. However, as we move towards the mid-abdomen, we have TA aponeurosis or rarely TA muscle of little bulk.

Understanding the Interplay Between Paraspinal Muscle Atrophy and Lumbar Endplate Degeneration: A 3-Year Longitudinal Study.

Retrospective analysis of longitudinal data. To assess the association between the paraspinal musculature (PM) and lumbar endplate degeneration. The PM is essential for spinal stability, while the vertebral endplate is pivotal for nutrient transport and force distribution. The clinical importance of both has been highlighted in recent literature, though little is known about their interaction. We identified patients with lumbar MRI scans due to low back pain, with a 3-year interval between MRI scans. Endplate damage was assessed by the total endplate score (TEPS) at each lumbar level. The PM was evaluated for its functional cross-sectional area (fCSA) and fatty infiltration (FI) at the L4 level. We used a generalized mixed model to analyze the association between PM parameters and TEPS at timepoint one, adjusting for age, sex, BMI, diabetes, hypertension, and smoking status. The association with the progression of endplate damage was analyzed through an ordinal regression model, additionally adjusted for TEPS at baseline. 329 patients were included, with a median follow-up time of 3.4 years. Participants had a median age of 59 and a BMI of 25.8kg/m2. In the univariate analysis, FI of the posterior PM was significantly associated with TEPS at baseline (β: 0.08, P<0.001) and progression of TEPS (OR: 1.03, P=0.020) after adjustment for confounders. The β and OR in this analysis are per percent of FI. In a binary analysis, patients with FI ≥ 40% had an OR of 1.92 (P=0.006) for the progression of TEPS. This is the first longitudinal study assessing the relationship between PM and endplate degeneration, demonstrating the association between PM atrophy and progression of endplate degeneration. This insight may aid in identifying patients at risk for degenerative lumbar conditions and guide research into preventive measures.

Association Between Fat Depletion and Prognosis of Amyotrophic Lateral Sclerosis: CT-Based Body Composition Analysis.

The purpose of this study was to present the results of our investigation of the prognostic value of adipopenia and sarcopenia in patients with amyotrophic lateral sclerosis (ALS). Consecutive patients with ALS with abdominal computed tomography (CT) were retrospectively identified at a single tertiary hospital between January 2010 and July 2021. Deep learning-based volumetric CT body composition analysis software was used to obtain abdominal waist fat volume, fat attenuation, and skeletal muscle area at the L3 level, then normalized to the fat volume index (FVI) and skeletal muscle index (SMI). Adipopenia and sarcopenia were defined as the sex-specific lowest quartile and SMI reference values, respectively. The associations of CT-derived body composition parameters with clinical variables, such as body mass index (BMI) and creatinine, were evaluated by Pearson correlation analyses, and associations with survival were assessed using the multivariable Cox regression analysis. Eighty subjects (40 men, 65.5 ± 9.4 years of age) were investigated (median interval between disease onset and CT examination = 25 months). The mean BMI at the CT examination was 20.3 ± 4.3 kg/m2 . The BMI showed a positive correlation with both FVI (R = 0.70, p < 0.001) and SMI (R = 0.63, p < 0.001), and the serum creatinine level was associated with SMI (R = 0.68, p < 0.001). After adjusting for sex, age, King's stage, BMI, creatinine, progression rate, and sarcopenia, adipopenia was associated with shorter survival (hazard ratio [HR] = 5.94, 95% confidence interval [CI] = 1.01, 35.0, p = 0.049). In a subgroup analysis for subjects with nutritional failure (stage 4a), the HR of adipopenia was 15.1 (95% CI = 2.45, 93.4, p = 0.003). Deep learning-based CT-derived adipopenia in patients with ALS is an independent poor prognostic factor for survival. ANN NEUROL 2023;94:1116-1125.

Case Series: Novel Use of a Erector Spinae Plane Block At A Lumbar Spinal Level For Coverage Of Sacral Dermatomes

The erector spinae plane (ESP) block is a recent and novel regional anesthesia procedure used primarily for the thoracic region. There is limited use of this block for the lumbar and sacral regions. Here we investigate the use of lumbar ESP blocks for three cases; hip disarticulation, penile burn, and perineal injury. For each case, an 18-gauge Tuohy needle was inserted into the paraspinous region at the L4 level and caudally directed towards the interfacial plane posterior to the transverse process via ultrasound. Once in place, 20-30 mL of 0.5% bupivacaine was injected. Opioid consumption was measured before and after block placement to evaluate for pain control. The ESP block yielded a significant reduction in opioid use for the penile burn and perineal injury cases, while a non-significant reduction was observed in the hip disarticulation case. The use of lumbar ESP block has shown the feasibility and effectiveness for sacral innervated injuries. This nerve block technique has strong potential to improve patient satisfaction and pain control while minimizing opioid reliance in the postoperative and traumatic injury recovery periods for lumbar and perineal injury patients.

Morphological and Morphometric Analysis of the Renal Artery Using Computed Tomographic Angiography

Objective: The anatomical features of the renal arteries are important for the diagnosis of various diseases affecting the kidneys and the renal arteries (RA), as well as for preoperative planning of surgical interventions. The objective of this study was to conduct a comprehensive analysis of the morphological and morphometric parameters of renal arteries specific to the Turkish population. Methods: RA diameter, angle, and distance to other vessels were performed on computed tomography angiography images of 299 patients (156 women, 143 men), considering their branching variations and the level of origin from the abdominal aorta. Results: The frequency of RA variations was 16.5%. The right RA was observed to arise between the lower T12 level and middle L4 level, most commonly (25.39%) at the L1-2 disc level. The left RA was found to originate between the upper T12 level and lower L3 level, mostly (27.44%) at the L1-2 disc level. The mean diameter of the right RA was 5.49±1.24 mm in females and 6.01±1.69 mm in males, while the mean diameter of the left RA was 5.96±1.44 mm in females and 6.45±1.74 mm in males. The mean exit angle of the right RA from the abdominal aorta was 57.06±17.27° in females and 57.65±16.62° in males, and that of the left RA was 67.05±18.13° in females and 70.37±17.42° in males. The distance of the right RA to the celiac trunk was 3.1±1.29 cm, and its distance to the aortic bifurcation was 9.56±1.52 cm. The distance of the left RA to the celiac trunk was 3.27±1.25 cm, and its distance to the aortic bifurcation was 9.38±1.41 cm. Analysis of the relationship of the study parameters with age showed statistically significant correlations between age and the left RA diameter and between age and the distance of both the right and left renal arteries to the celiac trunk. Conclusion: This study could contribute to the literature on renal artery morphology and morphometry in the Turkish population and provide guidance to clinicians.

Is there an anatomic basis for the different behavior of Lenke types 1AR and 1AL in idiopathic scoliosis? A study on facet joint tropism influence.

AIS type 1 Curves are sub-classified based on the tilt of L4 as 1AR and 1AL. These curves are different w.r.t their curve behavior, progression and level selection. Presently there is no known anatomic etiology for the different behavior. Facet tropism (FT) is defined as the asymmetry between the facet angle of the left and right facet joints. The purpose of this study was to evaluate the correlation between facet tropism in the lumbar segments and occurrence of type 1AR and 1AL curves in AIS patients. AIS patients with diagnosis of type 1 AR and 1AL right thoracic AIS curves who underwent posterior instrumented fusion were queried from a single institutions' database. Patients needed to have an MRI of their entire spine to be included. L2-3, L3-4 and L4-5 Facet angles (FA, angle made by the facet line with the mid-sagittal line at respected vertebral level) were calculated. FT was classified as follows: ≤ 5° (minimal), 6- 10° (mild) and ≥ 11° (severe). 1AR and 1AL curves were compared for FA, FT and FT grade at each lumbar segmental levels. One hundred nineteen patients were included (77 females, mean age-13.85 years, mean BMI- 21.63, 73 1AL and 46 1AR). The mean thoracic Cobb was 52.5 ± 9.8°, thoracic kyphosis was 28.12 ± 12° and lumbar lordosis was 53.48 ± 12.6°. L3-4 FA on the right side was more coronally oriented in 1AR curves compared to 1AL curves (37° vs. 31°, p = 0.04). On comparing FT at each level, 1AR curves had a higher FT at L3-4 (1.5° vs. -2.3°, p = 0.01) and L4-5 levels (5.8° vs. -0.28°, p < 0.001) compared to 1AL patients. Similarly, 1AR patients had significantly more patients with severe FT at L3-4 (34.8% vs. 13.7%, p = 0.02) and at L4-5 (17.3% vs. 6.8%, p = 0.01) compared to 1ALcurves. L3-4 joints are more coronally oriented in 1AR curves compared to 1AL curves. 1AR patients displayed higher FT at L3-4 and L4-5 compared to 1AL patients. 1AR curves also reveal a higher percentage of severe FT at L3-4 and L4-5 levels. This may influence the curve behavior and progression in these two curve types.

Does index-level pedicle screw instrumentation affect cage subsidence after vertebral body replacement? – A biomechanical study in human cadaveric osteoporotic specimens

BackgroundVertebral body replacement is a common surgical procedure for treatment of disorders associated with spinal instability. Therefore, pedicle screws are usually inserted in adjacent vertebrae for stabilization of the posterior column, however, there is lack of evidence whether implantation of index-level pedicle screws is beneficial or not. This biomechanical study aims to investigate the effect of pedicle screw instrumentation on axial stability following vertebral body replacement. MethodsUnstable fracture at L3 level was simulated in lumbar spines from six human cadaveric specimens. Then instrumentation was performed one level above / one level below index level in three specimens and further, three specimens were instrumented at index-level (L3) additionaly. Then we used a testing protocol for biomechanical evaluation of axial loading on human cadaveric lumbar spines until cage subsidence occurred. FindingsOur results show that index-level instrumented spines endured significantly higher load until cage subsidence occurred compared to non-index-level instrumented specimens (p = 0.05). InterpretationOur results demonstrate pedicle screw instrumentation at index-level vertebra should be considered when possbile as it may have a protective effect against cage subsidence in patients undergoing vertebral body replacement surgery.

The lower Osteotomy Level is Associated With Decreased Revision Surgery Due to Mechanical Complications After Three-Column Osteotomy in Patients With Adult Spinal Deformity: A Multi-Institutional Retrospective Study.

A multi-institutional retrospective study. To investigate risk factors of mechanical failure in three-column osteotomy (3COs) in patients with adult spinal deformity (ASD), focusing on the osteotomy level. We retrospectively reviewed 111 patients with ASD who underwent 3COs with at least 2years of follow-up. Radiographic parameters, clinical data on early and late postoperative complications were collected. Surgical outcomes were compared between the low-level osteotomy group and the high-level osteotomy group: osteotomy level of L3 or lower group (LO group, n = 60) and osteotomy of L2 or higher group (HO group, n = 51). Of the 111 patients, 25 needed revision surgery for mechanical complication (mechanical failure). A lower t-score (odds ratio [OR] .39 P = .002) and being in the HO group (OR 4.54, P = .03) were independently associated with mechanical failure. In the analysis divided by the osteotomy level (LO and HO), no difference in early complications or neurological complications was found between the two groups. The rates of overall mechanical complications, rod failure, and mechanical failure were significantly higher in the HO group than in the LO group. After propensity score matching, mechanical complications and failures were still significantly more observed in the HO group than in the LO group (P = .01 and .029, respectively). A lower t-score and osteotomy of L2 or higher were associated with increased risks of mechanical failure. Lower osteotomy was associated with better correction of sagittal balance and a lower rate of mechanical complications.

Bilateral Lumbar Artery Perforator Flaps for Breast Reconstruction: A Perforator Classification System.

Autologous breast reconstruction is continually evolving, with focus on the ideal donor site. This study presents 108 consecutive simultaneous lumbar artery perforator (LAP) flaps and a perforator classification system. A retrospective review of all LAP flaps was completed, and appropriate data were recorded. All simultaneous bilateral LAP flaps were included, and perforator patterns were assessed using CT angiography (CTA). Fifty-four patients (108 flaps) were included in the final review. The mean patient age was 50.7 years, and the mean body mass index was 26.6. Mean ischemia times for all flaps and grafts were 130 ± 64.5 and 300.6 ± 97.3 minutes, respectively. The average pedicle length was 4.6 ± 1.5 cm, and the average composite graft length was 6.2 ± 1.7 cm. Donor-site complications consisted of seromas (10 patients [19%]), hematomas (6 patients [11%]), procedural wounds (4 patients [8%]), and infections (2 patients [4%]). The total flap loss rate was 2.8%. Perforators were classified into categories based on pedicle pattern, lumbar spine level, and clusters, all in relation to posterior iliac bone as seen per CTA. Vascular pedicle patterns were categorized as type 1 (43.9%), 2 (45.6%), 3 (8.8%), or 4 (1.8%). Perforators were dissected at lumbar spine level L3 in 51.8% of patients, L4 in 46.5%, and L5 in 1.8%. The authors present a CTA-directed anatomic perforator classification system to assist in preoperative planning, dissection, and choice of the composite graft best suited for particular perforator patterns or calibers. Simultaneous LAP flaps can be performed successfully with excellent outcomes in cases unsuitable for other flaps. Therapeutic, IV.