Lumbar Segments Research Articles

Complex neural tube and skeletal malformations, resembling Chiari malformations, in two calves.

Two 1-day-old full-term female calves from different farms located in the Brazilian state of Rio Grande do Sul were unable to stand due to paresis of the pelvic limbs. Both calves had spina bifida on the spinal lumbar segment and were submitted to euthanasia due to poor prognosis. Postmortem examination revealed cerebellar herniation, caudal displacement of the brainstem, rostral deviation of the cranial nerves, caudal extension of occipital lobes, absence of dorsal lamina of lumbar vertebrae with exposed spinal cord, myelodysplasia, kyphosis, segmental spinal agenesis, renal fusion, muscular atrophy, and arthrogryposis. Histology highlighted myelodysplasia (syringomyelia and diplomyelia) and muscular atrophy. The reverse transcription-polymerase chain reactions for ruminant pestivirus were negative. Based on these lesions, the diagnosis of complex neural tube and skeletal malformations was made. A review of previous publications on calves diagnosed with these malformations, originally called Chiari or Arnold-Chiari malformations, revealed a wide range of nervous system and skeletal lesions. These variations amplified the uncertainty regarding whether all cases represent the same disorder and reinforced the importance of reconfiguring the terminology.

A comparative assessment of age-related nicotinamide adenine dinucleotide phosphate-diaphorase positivity in the spinal cord and medulla oblongata of pigeons, rats, and mice.

Nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase (N-d) positive neurons have been extensively studied across various animals, and N-d neurodegenerative neurites have been detected in some aged animal models. However, detailed knowledge on N-d positivity and aging-related alterations in the spinal cord and medulla oblongata of pigeons is limited. In this study, we investigated N-d positivity and age-related changes in the pigeon's spinal cord and medulla oblongata and compared them to those in rats and mice. Pigeons, had more N-d neurons in the dorsal horn, around the central canal, and in the column of Terni in the thoracic and lumbar segments, with scattered neurons found in the ventral horn of the spinal segments. N-d neurons were also present in the white matter of the spinal cord. Morphometric analysis revealed that the size of N-d soma in the lumbosacral, cervical, and thoracic regions was substantially altered in aged pigeons compared to young birds. Furthermore, the lumbar to sacral segments underwent significant morphological alterations. The main findings of this study were the presence of age-related N-d positive bodies (ANB) in aged pigeons, predominantly in the external cuneate nucleus (CuE) and occasionally in the gracilis and CuEs. ANBs were also identified in the gracile nuclei and spinal cord in the aged rats and mice, whereas in aged rats, ANBs were detected in the CuE spinal nucleus. Immunohistochemistry showed that the age-related alterations occurred in the cell types and neuropeptides in old animals. The results suggest weak inflammatory response and neuronal dysfunction in the spinal cord in aged pigeons. Our results suggested that the ANB could be a potential aging marker for the central nervous system.

The Low Back Pain - Looking For a Physiotherapeutic Approach

BACKGROUND: Low back pain (LBP) is one of the most common neurological complaints. It affects young people but has a slow progression even at a later age. LBP is a condition with a rich clinical picture – pain, severely limited range of motion in the spinal column (especially in the area of the L4-L5 segment) and sacro-iliac joints, difficulty walking. Physiotherapy has an essential role in maintaining the general condition and improving the quality of life for this contingent of patients. AIM: The aim of the present study is to create and approve a physiotherapy methodology for pain reduction in patients diagnosed by a neurologist – radiculitis of the lumbo-sacral plexus. METHODS: 20 clinically proven patients divided into two groups were included in the study. After signing informed consent declarations and assessment of anthropometric data (age, height, and weight), the subjects were evaluated with neurological tests such as Lasegue test and dolorimetry. Results were also reported on the Barthel index scale. RESULTS: The dynamics of dolorimetry results, quality of life, and mobility in the spine area (especially the lumbar segment) were monitored in the two studied groups, with the results in the experimental group demonstrating better values (p < 0.0001). CONCLUSION: There is no unified system for pain reduction in patients with LBP. As a result of applied physiotherapy, including modern techniques for myofascial massage, a faster increase in joint mobility in the area of the spine and sacroiliac joints, an improvement in muscle strength and, above all, a reduction in pain symptoms were found.

Biomechanical Behavior of Injected Cement Spacers versus Traditional Cages in Low-Density Lumbar Spine under Compression Loading.

Background and Objectives: Osteoporosis renders the use of traditional interbody cages potentially dangerous given the high risk of damage in the bone-implant interface. Instead, injected cement spacers can be applied as interbody devices; however, this technique has been mainly used in cervical spine surgery. This study aimed at investigating the biomechanical behavior of cement spacers versus traditional cages in lumbar spine surgery. Materials and Methods: Destructive monotonic axial compression testing was performed on 20 human cadaveric low-density lumbar segments from elderly donors (14 f/6 m, 70.3 ± 12.0 y) treated with either injected cement spacers (n = 10) or traditional cages (n = 10) without posterior instrumentation. Stiffness, failure load and displacement were compared. The effects of bone density, vertebral geometry and spacer contact area were evaluated. Results: Cement spacers demonstrated higher stiffness, significantly smaller displacement (p < 0.001) and a similar failure load compared to traditional cages. In the cage group, stiffness and failure load depended strongly on bone density and vertebral height, whereas failure displacement depended on vertebral anterior height. No such correlations were identified with cement spacers. Conclusions: Cement spacers used in lumbar interbody stabilization provided similar compression strength, significantly smaller failure displacement and a stiffer construct than traditional cages that provided benefits mainly for large and strong vertebrae. Cement stabilization was less sensitive to density and could be more beneficial also for segments with smaller and less dense vertebrae. In contrast to the injection of cement spacers, the optimal insertion of cages into the irregular intervertebral space is challenging and risks damaging bone. Further studies are required to corroborate these findings and the treatment selection thresholds.

Interpretable Machine Learning Models Based on SHapley Additive exPlanations for Predicting the Risk of Cerebrospinal Fluid Leakage in Lumbar Fusion Surgery.

Retrospective study. The objective of this investigation was to formulate and internally verify a customized machine learning (ML) framework for forecasting cerebrospinal fluid leakage (CSFL) in lumbar fusion surgery. This was accomplished by integrating imaging parameters and employing the SHapley Additive exPlanation (SHAP) technique to elucidate the interpretability of the model. Given the increasing incidence and surgical volume of spinal degeneration worldwide, accurate predictions of postoperative complications are urgently needed. SHAP-based interpretable ML models have not been used for CSFL risk factor analysis in lumbar fusion surgery. Clinical and imaging data were retrospectively collected from 3505 patients who underwent lumbar fusion surgery. Six distinct machine learning models were formulated: extreme gradient boosting (XGBoost), decision tree (DT), random forest (RF), support vector machine (SVM), Gaussian naive Bayes (GaussianNB), and K-nearest neighbors (KNN) models. Evaluation of model performance on the test dataset was performed using performance metrics, and the analysis was executed through the SHAP framework. CSFL was detected in 95 out of 3505 patients (2.71%). Notably, the XGBoost model exhibited outstanding accuracy in forecasting CSFLs, with high precision (0.9815), recall (0.6667), accuracy (0.8182), F1 score (0.7347), and AUC (0.7343). Additionally, through SHAP analysis, significant predictors of CSFL were identified, including ligamentum flavum thickness, zygapophysial joint degeneration grade, central spinal stenosis grade, decompression segment count, decompression mode, intervertebral height difference, Cobb angle, intervertebral height index difference, operation mode, lumbar segment lordosis angle difference, Meyerding grade of lumbar spondylolisthesis, and revision surgery. The combination of the XGBoost model with the SHAP is an effective tool for predicting the risk of CSFL during lumbar fusion surgery. Its implementation could aid clinicians in making informed decisions, potentially enhancing patient outcomes and lowering healthcare expenses. This study advocates for the adoption of this approach in clinical settings to enhance the evaluation of CSFL risk among patients undergoing lumbar fusion.

Does Minimally Invasive Hemilaminectomy for Intradural Extramedullary Tumor Resection Prevent Postlaminectomy Kyphosis or Lordosis Loss?

Minimally invasive hemilaminectomy is a safe and effective alternative to open laminectomy for treating intradural extramedullary tumors. There are no reports of postoperative kyphosis after this approach. This study aims to determine whether performing minimally invasive spine surgery hemilaminectomy for intradural extramedullary tumors can prevent the development of postlaminectomy kyphosis (PLK) or lordosis loss. Sixty-five patients with spinal intradural extramedullary tumors who underwent minimally invasive hemilaminectomy surgery and complete pre and postoperative radiologic imaging were included. The effect of the surgical approach on the spinal sagittal axis was assessed by comparing pre- versus postoperative segmental and local Cobb angles at different spinal levels, considering anatomical localization (cervical, thoracic, lumbar, and transition segments) and functional features (mobile, semi-rigid, and transition segments), as well as the extent of the surgical approach (1, 2, or 3 levels) and follow-up. None of the patients had an increase in thoracic kyphosis nor a loss of cervical or lumbar lordosis greater than or equal to 10° after undergoing the minimally invasive spine surgery hemilaminectomy approach.More than 5° of increase in kyphosis was detected on 7.4% and 11.1%, for the segmental and the local angles, respectively; meanwhile, for patients with loss of lordosis, this deviation was detected in 5.3%, for both angles. The occurrence of PLK was more common than that of lordosis loss, but mainly manifested in postoperative angle impairment of less than 5°. No significant differences were evidenced, considering theapproach length. Hemilaminectomy represents a promising approach for preventing PLK and postlaminectomy lordosis loss following intradural extramedullary tumor resection.

Transcutaneous Transmission of Light of Photobiomodulation Therapy Wavelengths at 808 nm, 915 nm, 975 nm, and 1064 nm to the Spinal Canal of Cadaver Dogs

This study compared the transcutaneous target level irradiances from the thoracic to lumbar segments of the interior spinal canal in three cadaver dogs, measured for light at four wavelengths (808 nm, 915 nm, 975 nm, and 1064 nm), common in photobiomodulation therapy (PBMT). Intra-spinal irradiances at nine sites spanning approximately 8 cm in length were measured using a flexible intra-spinal probe under surface application of continuous-wave (CW) light with powers ranging from 0.5 W to 2 W. Surface illumination was applied using an acupuncture treatment head in three modes: non-contact with skin removed, non-contact with skin intact, and contact with skin intact. During surface application, the treatment head was positioned over the spinal canal near the 13th vertebrae (T13, surface site 1), and approximately 4 cm (surface site 5) and 8 cm (surface site 9) caudal to T13. At each position of the treatment head, the light was multiplexed among the four wavelengths at the same power setting. In all three modes of surface application, the target level irradiance at the 1064 nm wavelength was significantly greater than that at the other three wavelengths (p ≤ 0.0017). At a surface irradiance of ~157 mW/cm2, corresponding to 0.5 W light applied with the treatment head directly in contact with the skin, the intra-spinal irradiance at 1064 nm reached 0.137 ± 0.095 mW/cm2. Obtaining a dosage of PBMT-associative wavelengths of this magnitude at the level of the spinal canal may guide focused research into the transcutaneous applicability of PBMT for spinal cord injuries.

Impact of Supine versus Prone Positioning on Segmental Lumbar Lordosis in Patients Undergoing ALIF Followed by PSF: A Comparative Study.

Background: Anterior lumbar interbody fusion (ALIF) and posterior spinal fusion (PSF) play pivotal roles in restoring lumbar lordosis in spinal surgery. There is an ongoing debate between combined single-position surgery and traditional prone-position PSF for optimizing segmental lumbar lordosis. Methods: This retrospective study analyzed 59 patients who underwent ALIF in the supine position followed by PSF in the prone position at a single institution. Cobb angles were measured preoperatively, post-ALIF, and post-PSF using X-ray imaging. One-way repeated measures ANOVA and post-hoc analyses with Bonferroni adjustment were employed to compare mean Cobb angles at different time points. Cohen's d effect sizes were calculated to assess the magnitude of changes. Sample size calculations were performed to ensure statistical power. Results: The mean segmental Cobb angle significantly increased from preoperative (32.2 ± 13.8 degrees) to post-ALIF (42.2 ± 14.3 degrees, Cohen's d: -0.71, p < 0.0001) and post-PSF (43.6 ± 14.6 degrees, Cohen's d: -0.80, p < 0.0001). There was no significant difference between Cobb angles after ALIF and after PSF (Cohen's d: -0.10, p = 0.14). The findings remained consistent when Cobb angles were analyzed separately for single-screw and double-screw ALIF constructs. Conclusions: Both supine ALIF and prone PSF significantly increased segmental lumbar lordosis compared to preoperative measurements. The negligible difference between post-ALIF and post-PSF lordosis suggests that supine ALIF followed by prone PSF can be an effective approach, providing flexibility in surgical positioning without compromising lordosis improvement.

A Comparative Study to Analyze the Effect of Lumbar Stabilization and Conventional Back Extension Exercises on Mechanical Pain in Patients with Chronic Low Back Pain in Greater Noida

Lumbar discomfort is a major problem due to its harmful effects on health and high frequency in the general population. Depending on where and how long the pain lasts, there are three general categorizations for Lumbar discomfort: acute less than 6 weeks, sub-acute 6 to 12 weeks, and chronic more than 12 weeks. Several theories concerning the cause of nonspecific LBP feature poor posture, low body mass, hamstring flexibility, psychological discomfort, diminished trunk extensor endurance, and faulty muscular control of trunk. Pain in the lower back is a challenging illness which can result from injuries pertaining to the muscles and ligaments providing support vertebral column or from overuse or strain. One common treatment method for Lumbar discomfort is exercise therapy. This includes diverse forms of therapies including muscular strengthening, several forms of flexibility and stretching, and cardiovascular exercise for overall physical fitness. Normally, the stabilization system's job is to give the spine enough stability to meet the demands of changing circumstances immediately due to the posture changes with static and dynamic loads. As Per traditional understanding, spinal stabilization primarily relies on spinal biomechanics, the intervertebral disc, spinal ligaments, and osseous components. The stabilization and mobility of the lumbar spine can be facilitated by any muscle that exits the lumbar region. However, according to certain research, the lumbar multifidus and transverses abdominis muscles are very crucial for the stability of the lumbar segment. There is preliminary data indicating that those with long-term Lumbar discomfort do not properly recruit their core muscles and display core weakness13. Standard Exercise for back extension and exercises for lumbar stability both are used to treat low back discomfort. Thus, an effort is undertaken to compare and investigate the benefits of traditional back extension exercises and lumbar stabilization activities in patients with chronic Lumbar discomfort.

A retrospective review of gram-negative spinal infections in a single tertiary spinal centre over six years.

Gram-negative infections are associated with comorbid patients, but outcomes are less well understood. This study reviewed diagnosis, management, and treatment for a cohort treated in a tertiary spinal centre. A retrospective review was performed of all gram-negative spinal infections (n = 32; median age 71 years; interquartile range 60 to 78), excluding surgical site infections, at a single centre between 2015 to 2020 with two- to six-year follow-up. Information regarding organism identification, antibiotic regime, and treatment outcomes (including clinical, radiological, and biochemical) were collected from clinical notes. All patients had comorbidities and/or non-spinal procedures within the previous year. Most infections affected lumbar segments (20/32), with Escherichia coli the commonest organism (17/32). Causative organisms were identified by blood culture (23/32), biopsy/aspiration (7/32), or intraoperative samples (2/32). There were 56 different antibiotic regimes, with oral (PO) ciprofloxacin being the most prevalent (13/56; 17.6%). Multilevel, contiguous infections were common (8/32; 25%), usually resulting in bone destruction and collapse. Epidural collections were seen in 13/32 (40.6%). In total, five patients required surgery, three for neurological deterioration. Overall, 24 patients improved or recovered with a mean halving of CRP at 8.5 days (SD 6). At the time of review (two to six years post-diagnosis), 16 patients (50%) were deceased. This is the largest published cohort of gram-negative spinal infections. In older patients with comorbidities and/or previous interventions in the last year, a high level of suspicion must be given to gram-negative infection with blood cultures and biopsy essential. Early organism identification permits targeted treatment and good initial clinical outcomes; however, mortality is 50% in this cohort at a mean of 4.2 years (2 to 6) after diagnosis.

Tubular vs. mini-open lumbar discoidectomy: surgical-clinical outcome.

To evaluate the clinical-surgical results of the tubular vs. mini-open approach in lumbar discoidectomy. The tubular approach promises to reduce the number of rest days and an earlier return to daily activities and work. A case-control study of patients operated on for disc herniation using tubular surgery (case) and mini-open (control) was carried out. The variables investigated were as follow: radicular and lumbar pain, sex, age, failure in conservative treatment, single-level lumbar hernia, surgical time, bleeding, length of hospital stay, persistence of symptoms, complications, occupational activity, and reintegration into everyday activities. Through 100 surgeries performed, two groups were created, tubular and mini-open, with 50 patients each, with L4-L5 or L5-S1 disc herniation, respectively. The most affected level was L4-L5 (69%). Of the total cases, a significant improvement was found (p < 0.05) at 15 postoperative days in the VAS and ODI scale in the tubular group with respect to mini-open. Complications such as surgical wound infection, durotomy, and persistent pain occurred. The tubular approach is a safe and effective option for herniated discs of the lumbar segment, and reduces surgical times, bleeding, and the time of reinsertion to daily activities of the patient.

Changes in trunk postural control with different types of mounts with relevance for hippotherapy

BackgroundHippotherapy uses horseback riding movements for therapeutic purposes. In addition to the horse's movement, the choice of equipment and types of positions are also useful in the intervention. Trunk postural control demands can be manipulated through varying mounting materials and patient positioning on the horse. The quantification of trunk dynamic parameters under the interaction of the different types of riding material and the position variations act upon trunk postural control provides insight into how children with neurotypical development respond to a similar hippotherapy session. This study aimed to evaluate the postural control of the trunk of children with neurotypical development when the riding materials and positioning of the feet and hands support were modified during horse riding. MethodsFifteen children with neurotypical development, aged 6–12 years old, of both sexes, participated in a hippotherapy session. Postural control was measured by the mean amplitudes of oscillation of the lumbar (L5) and thoracic (T5) segments in the mediolateral, anteroposterior and rotational planes with a portable inertial measurement system, in situations using the saddle or blanket, hands resting on the straps or thigh and feet free or supported on the stirrup. ResultsDifferences were observed in lumbar and thoracic oscillation in the mediolateral direction. Values were significantly higher with the use of the blanket when the hands were on the handle and feet in the stirrups, compared to the use of the saddle. When using the blanket and feet positioned in the stirrups, statistical differences with higher values occurred with the hands on the handle compared to the thigh positioning. ConclusionThe use of the blanket equipment associated with the support of the hands on the handles and feet on the stirrups produces greater mediolateral oscillation in the subjects. DescriptorsBalance. Stability. Children. Hippotherapy. Kinematics.

Exercise role on inflammatory and MCH-1 plasticity markers in severely contused spinal cord injured rodents

Approximately 17,500 new cases of Spinal cord Injury (SCI) occur annually in the United States. Growing evidence suggests that mobilizing the body following SCI through physical therapy regimens can help patients regain locomotor function. The immune response and the role of inflammation following SCI represents an important factor contributing to plasticity and recovery of function post-injury. The immune response uses both pro and anti-inflammatory factors to facilitate healing at the primary and secondary injury. In the severe case of SCI, inflammation can lead to maladaptive plasticity and that can hinder locomotor recovery. Pro-inflammatory cytokines such as Tumor necrosis factor alpha (TNF-a) can enhance the C-fiber activation in the dorsal horn resulting in sensitization and maladaptive plasticity. Exercise can also be pro-inflammatory. Exercise has been shown to decrease TNF-a levels and increases Interleukin-10 (IL-10) in human skeletal muscle. Bodyweight treadmill training in SCI animal has shown improvements in locomotor function. Interleukin-10 (IL-10), demonstrates potent anti-inflammatory effects in which it down-regulates TNF-alpha and its secondary effects. In addition, major histocompatibility complex class I proteins (MHC1), play a vital role in maintaining the structural integrity of neurons which is critical for fostering an environment for spinal plasticity to occur. In this study, we focus on the role of training paradigms to be used to facilitate locomotor recovery in spinally contused rats. The Body-Weight Supported Treadmill Training (BWSTT) and circular Bodyweight-Supported Ambulatory Rodent Trainer (cBART) both represent locomotor training for SCI animals. Mid-thoracic spinal cord contusion was performed, and the animals were allowed to recover for two weeks. The contused BWSTT alone, or cBART alone or combined BWSTT and cBART training groups were initiated at beginning of the third week for a total of 8-weeks of training. Controls include contused rats that received no training, and intact group (SHAM). At 10 weeks, the spinal cord was dissected for qPCR study. We measure the levels of TNF-alpha, MHC1, and IL-10 in the thoracic segment above the injury site, the injury site, Lumbar 1-3 and Lumbar 3-5 segment. Results show that in the cBART trained group, the MHC-1 expression in the L3-L5 segment was significantly greater when compared to the contused injury with no training intervention. No training effect was realized in MHC-1 in the L1-L3 trained groups. The training paradigms did not modulate TNF-a levels in the lumbar spinal cord segments. Lastly, IL-10 expression was undetectable in all the spinal cord segments. In this severe spinal cord contused model, we were only able to show modulation in the MHC-1 expression in the trained lumbar segment as function of exercise. Additional work will be required to consider the intensity of locomotor training and the severity of spinal cord contusion impact on these plasticity markers. Future understanding of these mechanisms may be useful in developing better locomotor training methods and drug targets for facilitation of recovery following SCI. CSULA RSCA 2020 MINI Grant- Dr. Joseph CSULA MORE Programs Offce, MBRS-URISE (1734GM145503) Bridges to Doctorate 5T23GM146700 NIH R25HD097701-04 - Dr. Ray De Leon. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Magnetic resonance imaging features and classification of intraspinal echinococcosis

ObjectiveThis study aimed to investigate the magnetic resonance imaging (MRI) features and classification of echinococcosis of the spinal canal. MethodsThe clinical manifestations and MRI findings and classification of 19 patients diagnosed with intraspinal echinococcosis over 10 years (2011–2020) were retrospectively analyzed. ResultsThe mean age of the nine males and 10 females was 39 years (range 28–65 years). Among these, the number of cases with thoracic, lumbar, sacral, thoracolumbar, and lumbosacral, cervical, and lumbar segments was nine (47 %), five (26 %), one (5 %), one (5 %), two (11 %), and one (5 %) cases, respectively. Furthermore, 13 cases (69 %) involved adjacent vertebral bodies, accessories, and surrounding soft tissues. The lesion was confined to the intramedullary, extramedullary subdural, extramedullary epidural, and multiple spaces in one (Type I) (5 %), four (Type II) (21 %), one (Type III) (5 %), and thirteen (69 %) cases, respectively. Moreover, nine cases (47 %) had a history of hydatid disease in the spine or other tissues. The clinical manifestations were chest and lumbosacral pain in 18 cases (95 %) and chest and lumbosacral pain accompanied by lower limb dysfunction in four cases (21 %). The MRI revealed different sizes of T1WI low-signal and T2WI high-signal vesicles with a “grape-like” appearance, with 16 cases (84 %) showing low signals on the edge of the cyst wall. ConclusionIntraspinal echinococcosis is rare, even in endemic areas. However, intraspinal echinococcosis should be considered when there is a history of echinococcosis in other sites or when there are clear MRI characteristics for the disease.

Gender differences in spinal mobility during postural changes: a detailed analysis using upright CT

Lumbar spinal alignment is crucial for spine biomechanics and is linked to various spinal pathologies. However, limited research has explored gender-specific differences using CT scans. The objective was to evaluate and compare lumbar spinal alignment between standing and sitting CT in healthy individuals, focusing on gender differences. 24 young and 25 elderly males (M) and females (F) underwent standing and sitting CT scans to assess lumbar spinal alignment. Parameters measured and compared between genders included lumbar lordosis (LL), sacral slope (SS), pelvic tilt (PT), pelvic incidence (PI), lordotic angle (LA), foraminal height (FH), and bony boundary area (BBA). Females showed significantly larger changes in SS and PT when transitioning from standing to sitting (p = .044, p = .038). A notable gender difference was also observed in the L4-S LA among the elderly, with females showing a significantly larger decrease in lordotic angle compared to males (− 14.1° vs. − 9.2°, p = .039*). Females consistently exhibited larger FH and BBA values, particularly in lower lumbar segments, which was more prominent in the elderly group (M vs. F: L4/5 BBA 80.1 mm2 [46.3, 97.8] vs. 109.7 mm2 [74.4, 121.3], p = .019 in sitting). These findings underline distinct gender-related variations in lumbar alignment and flexibility, with a focus on noteworthy changes in BBA and FH in females. Gender differences in lumbar spinal alignment were evident, with females displaying greater pelvic and sacral mobility. Considering gender-specific characteristics is crucial for assessing spinal alignment and understanding spinal pathologies. These findings contribute to our understanding of lumbar spinal alignment and have implications for gender-specific spinal conditions and treatments.

Radiographic and surgery-related predictive factors for increased segmental lumbar lordosis following lumbar fusion surgery in patients with degenerative lumbar spondylolisthesis.

This study aimed to evaluate preoperative (pre-op) radiographic characteristics and specific surgical interventions in patients with degenerative lumbar spondylolisthesis (DLS) who underwent lumbar fusion surgery (LFS), with a focus on analyzing predictors of postoperative restoration of segmental lumbar lordosis (SLL). A retrospective review at a single center identified consecutive single-level DLS patients who underwent LFS between 2016 and 2022. Radiographic measures included disc angle (DA), SLL, lumbar lordosis (LL), anterior/posterior disc height (ADH/PDH), spondylolisthesis percentage (SP), intervertebral disc degeneration, and paraspinal muscle quality. Surgery-related measures included cage position, screw insertion depth, spondylolisthesis reduction rate, and disc height restoration rate. A change in SLL ≥ 4° indicated increased segmental lumbar lordosis (ISLL), and unincreased segmental lumbar lordosis (UISLL) < 4°. Propensity score matching was employed for a 1:1 match between ISLL and UISLL patients based on age, gender, body mass index, smoking status, and osteoporosis condition. A total of 192 patients with an average follow-up of 20.9months were enrolled. Compared to UISLL patients, ISLL patients had significantly lower pre-op DA (6.78° vs. 11.84°), SLL (10.73° vs. 18.24°), LL (42.59° vs. 45.75°), and ADH (10.09mm vs. 12.21mm) (all, P < 0.05). ISLL patients were predisposed to more severe intervertebral disc degeneration (P = 0.047) and higher SP (21.30% vs. 19.39%, P = 0.019). The cage was positioned more anteriorly in ISLL patients (67.00% vs. 60.08%, P = 0.000), with more extensive reduction of spondylolisthesis (- 73.70% vs. - 56.16%, P = 0.000) and higher restoration of ADH (33.34% vs. 8.11%, P = 0.000). Multivariate regression showed that lower pre-op SLL (OR 0.750, P = 0.000), more anterior cage position (OR 1.269, P = 0.000), and a greater spondylolisthesis reduction rate (OR 0.965, P = 0.000) significantly impacted SLL restoration. Pre-op SLL, cage position, and spondylolisthesis reduction rate were identified as significant predictors of SLL restoration after LFS for DLS. Surgeons are advised to meticulously select patients based on pre-op SLL and strive to position the cage more anteriorly while minimizing spondylolisthesis to maximize SLL restoration.

Influence of paraspinal muscle degeneration and postoperative Roussouly classification restoration on mechanical complications in female patients with degenerative scoliosis after surgery

Objective: To investigate the impact of lumbar paraspinal muscle degeneration and postoperative failure to restore ideal Roussouly classification on the occurrence of mechanical complications (MC) following long-segment spinal correction surgery in female patients with degenerative scoliosis (DS). Methods: The clinical data of 72 female DS patients who underwent long-segment spinal correction surgery in Gulou Hospital from June 2017 to November 2021 were retrospectively analyzed. According to whether restoring the ideal Roussouly classification after surgery, the patients were divided into R group(recovery group) (n=51) and N group(non-recovery group) (n=21). According to whether mechanical complications occurred after operation within two years, the patients were divided into MC (mechanical complications)group (n=24) and NMC(non-mechanical complications) group (n=48). The RM group (n=14) experienced mechanical complications in the R group, while the RN group (n=37) did not. The NM group (n=10) experienced mechanical complications in the N group, while the NN group (n=11) did not.Radiographic assessment included Sagittal parameters of spine and pelvis, standardized cross-sectional area (SCSA) and fat infiltration rate (FI%) of paraspinal muscle at each lumbar disc level. Results: The age of DS patients in this study was (61.4±6.2) years.The incidence of MC was 33.33%(n=24)in all patients. The incidence of MC was 27.45%(n=14)in group R and 47.62%(n=10) in group N. The correction amount of pelvic tilt angle (PT) (-11.62°±10.06° vs -7.04°±8.45°, P=0.046) and T1 pelvic angle(TPA)(-12.88°±11.23° vs -7.31°±9.55°, P=0.031)during surgery were significantly higher in MC group compared to the NMC group. In group R, the FI% of paraspinal muscles in each lumbar segment of patients with postoperative MC was higher than that in patients without MC (P<0.05). In the R and N groups, there was no significant difference inthe SCSA of the lumbar paravertebral muscles between patients with postoperative MC and those without MC at each level (all P>0.05). Multivariate logistic regression analysis showed that the average FI% of lumbar PSM was correlated with the occurrence of MC after spinal fusion in DS patients.The average FI% of lumbar PSM≥22.63% was a risk factors for MC after spinal fusion (P=0.010,OR=1.088, 95%CI:1.020-1.160). Conclusions: Female DS patients with higher degree of preoperative paraspinal muscle degeneration have a higher incidence of postoperative mechanical complications. For these patients,.there is still a higher risk of mechanical complications after surgery even if the ideal Roussouly classification is restored after surgery.

Preoperative Hounsfield Units Predict Pedicle Screw Loosening in Osteoporotic Patients Following Short Segment Lumbar Fusion.

Retrospective Cohort. (1) To determine if vertebral HU values obtained from preoperative CT predict postoperative outcomes following 1-3 level lumbar fusion and (2) to investigate whether decreased BMD values determined by HU predict cage subsidence and screw loosening. In light of suboptimal screening for osteoporosis, vertebral computerized tomography(CT) Hounsfield Units(HU), have been investigated as a surrogate for bone mineral density(BMD). In this retrospective study, adult patients who underwent 1-3 level posterior lumbar decompression and fusion(PLDF) or transforaminal lumbar interbody and fusion(TLIF) for degenerative disease between the years 2017-2022 were eligible for inclusion. Demographics and surgical characteristics were collected. Outcomes assessed included 90-day readmissions, 90-day complications, revisions, patient reported outcomes(PROMs), cage subsidence, and screw loosening. Osteoporosis was defined as HU of ≤110 on preoperative CT at L1. We assessed 119 patients with a mean age of 59.1, of whom 80.7% were white and 64.7% were nonsmokers. The majority underwent PLDF(63%) compared to TLIF(37%), with an average of 1.63 levels fused. Osteoporosis was diagnosed in 37.8% of the cohort with a mean HU in the osteoporotic group of 88.4 compared to 169 in non-osteoporotic patients. Although older in age, osteoporotic individuals did not exhibit increased 90-day readmissions, complications, or revisions compared to non-osteoporotic patients. A significant increase in the incidence of screw loosening was noted in the osteoporotic group with no differences observed in subsidence rates. On multivariable linear regression osteoporosis was independently associated with less improvement in visual analog scale(VAS) scores for back pain. Osteoporosis predicts screw loosening and increased back pain. Clinicians should be advised of the importance of preoperative BMD optimization as part of their surgical planning and the utility of vertebral CT HU as a tool for risk stratification. 3.

Quantity, distribution and phenotype of newly generated cells in the intact spinal cord of adult macaque monkeys

The existence of proliferating cells in the intact spinal cord, their distribution and phenotype, are well studied in rodents. A limited number of studies also address the proliferation after spinal cord injury, in non-human primates. However, a detailed description of the quantity, distribution and phenotype of proliferating cells at different anatomical levels of the intact adult non-human primate spinal cord is lacking at present. In the present study, we analyzed normal spinal cord tissues from adult macaque monkeys (Macaca fuscata), infused with Bromo-2′-deoxyuridine (BrdU), and euthanized at 2h, 2 weeks, 5 weeks and 10 weeks after BrdU. We found a significantly higher density of BrdU + cells in the gray matter of cervical segments as compared to thoracic or lumbar segments, and a significantly higher density of proliferating cells in the posterior as compared to the anterior horn of the gray matter. BrdU + cells exhibited phenotype of microglia or endothelial cells (∼50%) or astroglial and oligodendroglial cells (∼40%), including glial progenitor phenotypes marked by the transcription factors Sox9 and Sox10. BrdU + cells also co-expressed other transcription factors known for their involvement in embryonic development, including Emx2, Sox1, Sox2, Ngn1, Olig1, Olig2, Olig3. In the central canal, BrdU + cells were located along the dorso-ventral axis and co-labeled for the markers Vimentin and Nestin. These results reveal the extent of cellular plasticity in the spinal cord of non-human primates under normal conditions.

Analyzing isolated degeneration of lumbar facet joints: implications for degenerative instability and lumbar biomechanics using finite element analysis.

The facet joint contributes to lumbar spine stability as it supports the weight of body along with the intervertebral discs. However, most studies on the causes of degenerative lumbar diseases focus on the intervertebral discs and often overlook the facet joints. This study aimed to investigate the impact of facet joint degeneration on the degenerative changes and diseases of the lumbar spine. A finite element model of the lumbar spine (L1-S1) was fabricated and validated to study the biomechanical characteristics of the facet joints. To simulate degeneration of the facet joint, the model was divided into four grades based on the number of degenerative segments (L4-L5 or L4-S1) and the contact condition between the facet joint surfaces. Finite element analysis was performed on four spine motions: flexion, extension, lateral bending, and axial torsion, by applying a pure moment to the upper surface of L1. Important parameters that could be used to confirm the effect of facet joint degeneration on the lumbar spine were calculated, including the range of motion (ROM) of the lumbar segments, maximum von Mises stress on the intervertebral discs, and reaction force at the facet joint. Facet joint degeneration affected the biomechanical characteristics of the lumbar spine depending on the movements of the spine. When analyzed by dividing it into degenerative onset and onset-adjacent segments, lumbar ROM and the maximum von Mises stress of the intervertebral discs decreased as the degree of degeneration increased in the degenerative onset segments. The reaction force at the facet joint decreased with flexion and increased with lateral bending and axial torsion. In contrast, lumbar ROM of the onset-adjacent segments remained almost unchanged despite severe degeneration of the facet joint, and the maximum von Mises stress of the intervertebral discs increased with flexion and extension but decreased with lateral bending and axial torsion. Additionally, the facet joint reaction force increased with extension, lateral bending, and axial rotation. This analysis, which combined the ROM of the lumbar segment, maximum von Mises stress on the intervertebral disc, and facet joint reaction force, confirmed the biomechanical changes in the lumbar spine due to the degeneration of isolated facet joints under the load of spinal motion. In the degenerative onset segment, spinal instability decreased, whereas in the onset-adjacent segment, a greater load was applied than in the intact state. When conducting biomechanical studies on the lumbar spine, considering facet joint degeneration is important since it can lead to degenerative spinal diseases, including adjacent segment diseases.