Search Results (100)

Introduction: With age and injury, the infiltration of fat in the paraspinal muscles can cause degeneration, disorganizing the structural integrity of the connective tissue and causing lower back pain (LBP). Human umbilical cord tissue allografts (UCTAs) have a collagen-rich matrix with various extracellular matrix (ECM) components that can replace damaged connective tissue. The objective of this paper is to analyze the preliminary findings from an observational repository on UCTAs for the supplementation of degenerated tissue in thoracic and lumbar paraspinal muscles refractory to standard conservative methods through patient-reported scales. Materials and Methods: A total of 117 patients from an observational repository were identified with paraspinal muscle degeneration. Patients received one to three applications of UCTAs; outcomes were tracked using the Numeric Pain Rating Scale (NPRS), the Western Ontario and McMaster University Arthritis Index (WOMAC), and the Quality-of-Life Scale (QOLS). Results: All groups showed positive improvement in the NPRS and WOMAC scales. Multi-application groups revealed statistically significant differences in the analyses. No adverse events or complications were reported. Discussion: Limitations included a lack of a control group, non-standardized application protocol, and the increase in recall and response bias due to using patient-reported measures. Conclusions: This pilot investigation presents the preliminary effectiveness necessary in hypothesis generation for continued research through randomized controlled trials to validate efficacy, establish optimal dosage protocols, and compare UCTAs to other conservative interventions. Full article

Background: As muscles atrophy, myocytes are replaced by fat and muscle strength diminishes, increasing thoracic supine kyphosis. Here, we investigate the relationship between muscle fat percentage (muscle–fat%) and thoracic supine kyphosis on CT. Methods: Thoracic Cobb angle was measured on supine CT scans from the AtlasDataset by four observers ($n=533$). Nine muscles were manually labeled on 100 scans (manual cohort). An nnU-Net model was trained on 80 cases with internal validation on 20 cases, then applied to segment the remaining 433 AtlasDataset scans (automated cohort). External segmentation benchmarking was performed on 30 cases from a separate open-source dataset. Associations between supine thoracic curvature and muscle–fat% were evaluated only in AtlasDataset. Results: Manual supine thoracic Cobb angle measurements demonstrated good inter-observer reproducibility (ICC(2,k) = 0.98) with a mean across-rater per-case SD of 3.4°. The nnU-Net achieved Dice scores >0.93 across all nine muscle groups on internal and external segmentation benchmarking. For both manual and automated cohorts, thoracic supine kyphosis correlated with muscle–fat% in the paraspinal (r = 0.35, 0.42), quadratus lumborum (r = 0.29, 0.33), vastus (r = 0.38, 0.32), psoas (r = 0.21, 0.23) and latissimus dorsi (r = 0.21, 0.17) muscles. Conclusions: Automated measurement of trunk muscle–fat% provides a reproducible imaging biomarker correlated with thoracic supine kyphosis on CT. Identifying fatty atrophy of core muscles may help identify potential targets for interventions in hyperkyphotic patients. Full article

Objectives: To characterize paraspinal muscle asymmetry using quantitative CT parameters in adolescent idiopathic scoliosis (AIS) and to examine the associations among muscle asymmetry, vertebral rotation, and curve severity. Methods: A retrospective analysis of 68 AIS patients was conducted. Quantitative CT measured the fatty infiltration rate (FIR) of paraspinal muscles at apical and stable vertebral levels. A muscle asymmetry index was calculated based on the FIR difference between concave and convex sides. Pearson and Spearman correlations and linear regression were used as the main analyses. AVR across upper, pedicle, and lower levels was evaluated using repeated-measures analysis, and SEM was performed as an additional analysis. Inter-observer repeatability of the apical muscle measurements was additionally assessed using an independently repeated segmentation dataset. Results: Paraspinal muscles at the apical region exhibited significant asymmetry, with concave FIR (33.4 ± 14.0%) being significantly higher than convex FIR (15.8 ± 6.8%; p < 0.001). In contrast, the stable vertebra showed no significant asymmetry. Muscle asymmetry was significantly associated with Cobb angle in both Pearson and Spearman analyses (r = 0.456, p = 0.0001; rho = 0.430, p = 0.0003). Its association with AVR was weaker (Pearson r = 0.232, p = 0.058; Spearman rho = 0.302, p = 0.013). In multivariable linear regression, both AVR (β = 1.222, 95% CI 0.827 to 1.617, p < 0.001) and muscle asymmetry (β = 0.375, 95% CI 0.167 to 0.583, p = 0.0006) remained independently associated with Cobb angle. Inter-observer repeatability for the apical muscle asymmetry index remained excellent (ICC(2,1) = 0.958, 95% CI 0.933 to 0.974). Conclusions: Significant asymmetric CT-derived low-attenuation change was observed in the apical paraspinal muscles of patients with AIS, predominating on the concave side. In this severe AIS cohort, paraspinal muscle asymmetry was consistently associated with Cobb angle and showed a weaker, more method-dependent association with AVR. These findings suggest a relationship between paraspinal muscle asymmetry and the severity of three-dimensional deformity. Full article

Low back pain (LBP) remains a leading cause of disability worldwide, imposing substantial socioeconomic burdens. Among its many causes, facetogenic pain accounts for a significant proportion of cases and is generally attributed to irritation of the richly innervated facet joint capsule, mediated by the medial branches of the dorsal rami. This narrative, hypothesis-driven review synthesises the current anatomical, biomechanical, neurophysiological, and clinical literature and advances a conceptual framework proposing a novel anatomical mechanism that may contribute to LBP. We hypothesise that ossification of the mamillo-accessory ligament (MAL) may be a plausible but under-recognised anatomical variant that may influence lumbar biomechanics and neural interfaces. The MAL connects the mammillary and accessory processes of lumbar vertebrae, serving as a stabilising anchor for deep paraspinal muscles and forming a conduit for the medial branch of the dorsal ramus (MBDR). Ossification of the MAL, resulting in a mamillo-accessory foramen, may theoretically impair spinal biomechanics via three principal mechanistic domains: (1) disruption of muscle attachment and segmental stabilisation, (2) potential compression of the MBDR causing denervation and muscle atrophy, and (3) chronic nerve entrapment leading to asymmetrical postural adaptations and persistent pain. Collectively, these pathways may contribute to spinal instability, facet degeneration, and variable response to standard interventional treatments such as radiofrequency ablation. Recognition of MAL ossification may have potential implications for clinical assessment, targeted imaging strategies, and treatment stratification in patients with chronic, non-specific LBP. Full article

Background: Kyphotic deformity following osteoporotic vertebral fracture (KDOVF) often requires corrective surgery to restore sagittal alignment; however, mechanical complications, such as proximal junctional failure (PJF) and distal junctional failure (DJF), remain major concerns. Selection of the lower instrumented vertebra (LIV) plays a critical role in balancing mechanical stability and functional preservation; however, the optimal criteria for LIV selection have not been fully established. Methods: This multicenter retrospective cohort study included 52 patients who underwent corrective surgery for KDOVF, with a minimum 1-year follow-up. The patients were classified into a long-fixation group with pelvic fixation (n = 27) and a short-fixation group with lumbar LIV fixation (n = 25). Mechanical complications, radiographic parameters, patient-reported outcomes, and paraspinal muscle fatty degeneration were compared between groups. Subgroup analysis was performed within the short-fixation group to identify the factors associated with DJF. Results: The incidence of PJF was significantly higher in the long-fixation group than in the short-fixation group (37% vs. 8%, p < 0.01), whereas DJF was observed only in the short-fixation group (24%). Within the short-fixation group, patients who developed DJF demonstrated significantly greater preoperative sagittal malalignment, a lower rate of cement-augmented pedicle screw, and more advanced fatty degeneration of the paraspinal muscles. The short-fixation group also showed better postoperative lumbar function. Conclusions: LIV selection in KDOVF surgery is associated with distinct patterns of junctional mechanical complications. Short fixation may be feasible in carefully selected patients who demonstrate preserved compensatory capacity. Full article

Background: The viscoelastic properties of muscle tissue are important factors affecting muscle performance; they play a significant role in maintaining spinal stability, as well as muscle contraction and function. Changes in these properties can result in pain, restricted movement, or poor posture. However, there is limited information in the literature regarding the viscoelastic properties of the paraspinal muscles, such as tone and stiffness, in individuals with chronic low back pain, which is one of the most common musculoskeletal disorders. The main aim of our study was to investigate the effects of reformer Pilates exercises on muscle viscoelastic properties in individuals with chronic low back pain for 4 weeks. In addition, our secondary aim was to examine the effects of Pilates-based exercises on body anthropometric values, pain intensity, functionality and kinesiophobia levels, sleep, and quality of life in individuals with chronic low back pain and to compare these parameters with a healthy group without low back pain. Methods: The study was carried out in a private clinic center and involved a total of 52 participants: 24 healthy subjects (control group) and 28 subjects with chronic low back pain (CLBP group). Pilates-based exercises were applied 2 days a week for 8 sessions for a total of 4 weeks. Muscle viscoelastic properties, body anthropometric values, pain intensity, functional status, kinesiophobia, sleep quality, and quality of life of all cases were evaluated. Muscle viscoelastic values were measured with a portable myotonometer, MyotonPro. Results: After 4 weeks of Pilates-based training, no significant improvements were observed in the parameters of muscle tone and stiffness in both groups (p > 0.05). It was found that pain intensity (p = 0.001), sleep quality (p = 0.004), quality of life (p = 0.019), and disability level (p = 0.003) improved after 4 weeks of Pilates-based training in subjects with chronic low back pain. In addition, there were significant differences in the parameters of the chest, waist, hip, and thigh circumferences after 4 weeks of Pilates-based training, except for the abdomen, in both groups (p < 0.05). Conclusions: A period of four weeks of Pilates exercises did not lead to significant changes in the muscle viscoelastic properties of the lumbar and abdominal muscles, although performing these exercises did result in regional thinning. The efficacy of Pilates exercises in reducing pain, disability, and kinesiophobia and in improving sleep and quality of life has been demonstrated in individuals suffering from chronic low back pain. Full article

Background/Objectives: Abdominal obesity, especially visceral adipose tissue (VAT), is an independent risk factor for coronary artery disease. This study aimed to investigate the association between single-slice CT-measured VAT and significant coronary artery stenosis and to establish an optimal VAT cut-off value for Taiwanese adults. Methods: Patients who underwent abdominal CT and coronary CT angiography (CTA) within 1 month of each other were enrolled in this retrospective study. Axial images of abdominal CT at the L4 pedicle level were selected for further VAT, subcutaneous adipose tissue, and paraspinal muscles analysis. Significant coronary artery stenosis was defined as any luminal stenosis of >50% of the diameter of the vessel that was measured in coronary CTA. Anthropometric and laboratory measurements, including height, weight, waist circumference (WC), blood pressure, blood glucose, and blood lipids, were also analyzed. Results: A total of 779 patients (300 females; 54.9 ± 9.96 years) were enrolled. Only VAT and systolic blood pressure correlated significantly with significant coronary artery stenosis. No significant differences were found in other demographic and anthropometric characteristics between the groups with and without significant coronary artery stenosis. Conclusions: Single-slice CT-measured VAT was associated with significant coronary artery stenosis, and a lower VAT cut-off is recommended for the Taiwanese population. Full article

Background and Clinical Significance: Radiation-induced lumbosacral plexopathy (RILP) is a rare but potentially debilitating complication of radiotherapy, typically affecting patients treated for pelvic malignancies. We report the first documented case of asymmetric RILP following radiotherapy for breast cancer. Case Presentation: A 64-year-old woman developed progressive left lower limb weakness, foot drop, and sensory disturbances four years after receiving locoregional radiotherapy extending to the left thoracoabdominal and lumbar areas. Electrophysiological studies revealed an asymmetric sensorimotor axonal neuropathy predominantly involving the left lower limb, without conduction block and sparing the upper limbs, whereas needle electromyography of the lower limbs showed fibrillation potentials, positive sharp waves, and fasciculations in the vastus lateralis, tibialis anterior, and medial gastrocnemius muscles on the left. Magnetic resonance imaging demonstrated edema and contrast enhancement of bilateral L2–L4 nerve roots with paraspinal muscle atrophy. Cerebrospinal fluid analysis showed albuminocytologic dissociation and elevated neurofilament levels. After exclusion of alternative diagnoses, including amyotrophic lateral sclerosis and inflammatory neuropathies, a diagnosis of radiation-induced peripheral neuropathy and RILP was made. The patient’s condition stabilized with physiotherapy and symptomatic treatment. Conclusions: This case highlights the need for heightened awareness of RILP as a late complication of breast cancer radiotherapy, underscoring the importance of accurate diagnosis to avoid misclassification and unnecessary treatments. Clinicians should carefully integrate all clinical elements—including a thorough remote medical history—since radiation-related neurological damage may manifest many years after the initial insult. Full article

Background/Objectives: Autosomal dominant polycystic kidney disease (ADPKD) is a major cause of end-stage kidney disease (ESKD), accounting for approximately 5–10% of patients receiving dialysis worldwide. The large and numerous cysts in the liver and kidneys cause abdominal distention and poor appetite. Previous studies showed that renal arterial embolization (RAE) reduces total kidney volume (TKV), increases appetite, and improves quality of life. This article aims to evaluate the efficacy of RAE in increasing psoas muscle (PM) and paraspinal muscle (PS) mass in patients with polycystic kidney disease. Methods: A retrospective study was conducted from May 2016 to December 2020. Thirty-five patients with PKD and ESKD who received RAE were enrolled. The clinical data, including age, sex, body weight, abdominal circumference, and laboratory results, including albumin, creatinine, estimated glomerular filtration rate, and dialysis vintage, were collected. TKV was calculated with the ellipsoid formula method, and muscle mass was measured with bilateral PM and PS areas at the third lumbar level. The associated clinical, laboratory, and imaging data were compared before and after RAE. Results: There were 19 females and 16 males with a mean age of 59.9 for the final analysis. There were significant changes between baseline and 3-month, 6-month, 12-month after RAE, such as a decrease in TKV (4684 ± 3361 vs. 4079 ± 3456, 3675 ± 3401, 2459 ± 1706 mL, all p < 0.001), an increase in the PM area (12.6 ± 5.8 vs. 13.3 ± 5.7, 14.7 ± 6.9, 14.3 ± 7.1 cm², all p < 0.05), but no difference in body weight, body mass index, albumin, hemoglobin, creatinine, or estimated glomerular filtration rate. The increase in the PM and PS was more obvious in the sarcopenic group than in the non-sarcopenic group in the 12-month follow-up (p = 0.001 and 0.016 vs. p = 0.205 and 0.259). Conclusions: RAE effectively reduces TKV, increases PM and PS mass, and serves as a candidate to reverse muscle loss in patients with PKD. Full article

Background and Objectives: This study set out to better understand how posture, spinal level, gender and muscle activation influence the biomechanical properties of the lumbar erector spinae (LES) in healthy young adults. We aimed to measure how these factors influence LES tone, stiffness, and damping using a myotonometry device. Materials and Methods: Thirty healthy young adults (14 males, 16 females; aged 20–25 years) were evaluated at bilateral L3–L5 levels in prone, unsupported sitting, and standing positions, both under relaxed conditions and during submaximal isometric lumbar extension. The myotonometer measured LES tone (Hz), stiffness (N/m), and damping (logarithmic decrement). For each outcome, a mixed-model repeated-measures ANOVA was conducted with Gender as a between-subject factor and Posture, Level, and Action (relaxed vs. contracted) as within-subject factors (Bonferroni-adjusted α = 0.0167). Results: Posture produced the most significant and consistent effects on all properties—stiffness, tone, and damping (p < 0.0167)—with sitting and standing generally increasing stiffness and tone compared to prone, and sitting showing the highest values. Gender significantly impacted stiffness and tone (p < 0.0167), with males showing higher values. Spinal level also significantly influenced damping, stiffness, and tone (all p < 0.0167), with differences more apparent in females. Significant interactions included the influence of Posture × Gender on tone and damping (p < 0.0167), and of Posture × Action on stiffness and tone (p < 0.0167), alongside a strong three-way interaction for Level × Action × Posture across all outcomes, suggesting posture-related responses depend on activation state and spinal level. Conclusions: LES biomechanical properties are strongly affected by posture and further modulated by muscle activation, gender, and spinal level. These results support the creation of posture- and gender-specific reference values and underscore the value of dynamic, posture-specific myotonometer-based assessments for paraspinal muscle evaluation and clinical planning. Full article

Adolescent idiopathic scoliosis (AIS) is a 3D structural deformity of the spine that can cause decreased spinal movement, paraspinal muscle weakness, or chronic pain. Our study aims to evaluate biomechanical and viscoelastic properties of the paravertebral muscles in adolescents with idiopathic S-type scoliosis, static plantar pressure, and stabilometry at the beginning of a physical exercise program and after 3 months. The myotonometry performed by using MyotonPro will determine five parameters (frequency, stiffness, logarithmic decrement, stress relaxation time, and ratio of relaxation time to deformation time). Measurements will be taken at the level of the left/right middle trapezius, left/right lower trapezius, left/right latissimus dorsi, and left/right lumbar erector muscles. Static pressure assessment and stabilometry (length described by the center of pressure, confidence area, and speed described by the center of pressure) will be determined by a PoData device in different testing positions (eyes open, eyes closed, head rotated to the right/left, head tilted to the right/left, and head in hyperextension). We expect to record a difference between the muscles on the concave side and the convex side in terms of myotonometric parameters, as well as differences between the initial and 3-month assessment. We predict an improvement in stabilometric parameters after the 3-month physical exercise program. Full article

Background/Objectives: Ankylosing spondylitis and diffuse idiopathic skeletal hyperostosis produce long-segment spinal ankylosis, altered biomechanics, and high fracture risk in the cervical spine. Paraspinal muscle degeneration (“spine-specific sarcopenia”) has been linked to pain, disability, and worse outcomes after cervical spine surgery, but the relationship between vertebral ankylosis and cervical paraspinal muscle health is unknown. We aimed to evaluate the association between vertebral ankylosis and cervical paraspinal muscle health using MRI-based measures of muscle quantity and quality. Methods: Adult patients with cervical vertebral ankylosis and available cervical MRI were identified at a single academic center and propensity score-matched 1:1 to patients without ankylosing conditions based on age, sex, body mass index, American Society of Anesthesiologists class, and comorbidity index. Axial T2-weighted images at C2-3 through C7-T1 were used to manually trace bilateral deep extensor and deep flexor muscles to obtain bilateral cross-sectional areas (CSAs) at each level. Extensor fatty infiltration was graded using the Goutallier classification. CSAs and Goutallier grades were compared between the matched groups. Results: Compared with matched controls, patients with vertebral ankylosis demonstrated significantly smaller deep extensor CSA at multiple cervical levels and higher Goutallier grades in the lower cervical spine and at the cervicothoracic junction. Deep flexor CSA tended to be smaller in the ankylosis group, but differences did not reach statistical significance. Conclusions: Vertebral ankylosis is associated with poorer cervical paraspinal muscle health, characterized by reduced extensor muscle bulk and increased fatty degeneration. These findings support conceptualizing ankylosing spinal conditions as disorders of both bone and muscle and highlight the cervicothoracic extensors as a potential target for risk stratification and rehabilitation strategies. Full article

Background/Objectives: Paraspinal muscles are important for maintaining cervical spine function and stability; however, the degeneration of these muscles is common in patients with degenerative disk disease. Such muscular changes may affect recovery trajectories and long-term functional outcomes after cervical spine surgery. This systematic review explores the existing literature on the relationship between the degree of paraspinal muscle degradation and functional outcomes following anterior cervical spine surgery in patients with cervical degenerative disk disease. Methods: A systematic review of the MEDLINE/Pubmed, Web of Science, and Embase databases was conducted according to the PRISMA guidelines up to June 2025. The inclusion criteria were patients who underwent surgery for cervical degenerative disk disease and assessments of the paraspinal muscles with magnetic resonance imaging. The methodological quality of the included studies was assessed using the Modified Newcastle–Ottawa Scale. Results: Following deduplication, a total of 3643 articles were screened, of which 6 met the inclusion criteria and were included in the review. Across these studies, a total of 515 patients were followed for at least one year. Two studies reported a negative association between paraspinal muscle degeneration and functional outcomes, three reported no association, and one reported a positive association. Conclusions: The available evidence on this topic is inconclusive. These mixed results highlight the need for further well-designed, adequately powered studies to clarify the relationship between paraspinal muscle degeneration and functional outcomes. Full article

Open posterior lumbar surgery involves detaching paraspinal muscles from the spine to decompress neural tissues and to place instruments. While this operation improves the quality of life, it often has adverse effects on skeletal muscles like inflammation, degeneration, and fibrosis. Corticosteroids are well known for their anti-inflammatory function. In this study, we assessed the protective effects of intramuscular injection of corticosteroid on injured paraspinal muscles following surgery on the spine. C2C12 cells were co-exposed to hypoxia and lipopolysaccharide (LPS) to simulate ischemia and inflammatory response after muscle retraction to assess the effect of steroid. In vivo experiment, animals first underwent paraspinous muscle splitting with retractors to induce muscle injury, and later were assessed for neurobehavior, electrophysiology, and protein level related to inflammatory or regeneration following intramuscular (IM) steroid injection. Steroid rescued reduced cell viability caused by hypoxia + LPS, and attenuated induced protein expression of iNOS, COX2, Bad, and Bax. In neurobehavioral assessments (CatWalk, Ethovision, Von Frey test, and open field locomotor), retraction of paraspinous muscles worsened behaviors that were improved by IM steroid injections. The electrophysiology study showed that IM steroid injection lessened the muscle denervation caused by retraction. Similarly, IM steroid injections also attenuated dorsal root ganglion antigenicity of CGRP, Iba-1, and CD68 induced by muscle retraction. Muscle retraction downregulated AChR, desmin, PSD 95, and GAP 43, whereas IM steroid injection attenuated the adverse effects. The restoration of muscle morphology and decreased fibrosis were also facilitated by IM dexamethasone. IM steroid injection appears to protect against retraction damage in paraspinous muscle following spinal surgery. IM steroid paraspinous muscle injection may provide beneficial effects in spinal operations. Full article

Despite its increasing use in veterinary rehabilitation, practical constraints—such as skin preparation and single-use electrodes—limit the wider adoption of surface electromyography (sEMG). Having conventional pre-gelled Ag/AgCl electrodes as reference, we made a pioneering comparison of the performance of reusable soft polymeric dry electrodes for recording paraspinal muscle activity in dogs during treadmill walking. Twelve clinically healthy Dachshunds from both genders were evaluated under two conditions, namely: (i) dry electrodes on untrimmed hair; and (ii) pre-gelled electrodes after trichotomy. Signals were acquired from the longissimus dorsi muscle at 1 kHz, processed with standardized filtering and rectification, and analyzed in both time and frequency domains. Dry electrodes yielded higher amplitude and Root Mean Square (RMS) values, but slightly lower power spectral density metrics when compared to pre-gelled electrodes. Nevertheless, frequency-domain results were broadly comparable between configurations. Dry electrodes reduce the preparation time, avoid hair clipping, and allow reusability without major signal degradation. While pre-gelled electrodes may still offer marginally superior stability during movement, our results suggest that soft polymeric dry electrodes present a feasible, less invasive, and more sustainable alternative for canine sEMG. These findings support further validation of dry electrodes in clinical populations, particularly for neuromuscular assessment in intervertebral disk disease. Full article