Hasil untuk "Diseases of the musculoskeletal system"

Lauren N. McGrath, David Moodie, Steven R. Feldman

Biologics are complex protein-based medications derived from living organisms, used primarily to treat immune-related diseases. Unlike small-molecule drugs synthesized from chemicals, biologics are produced using advanced biotechnology, making their replication difficult. Biosimilars are nearly identical alternatives to biologics, and they offer a cost-effective option that produces equivalent safety or efficacy outcomes as their reference biologics. Biosimilars are not classified as generic drugs and have a unique regulatory pathway. While biosimilars must demonstrate structural, functional, and clinical similarity to reference biologics, regulatory requirements vary across the US Food and Drug Administration (FDA), the European Medicines Agency (EMA), and the World Health Organization (WHO). The FDA used to mandate clinical studies for interchangeability status, while the EMA and WHO had more flexible approval pathways that enable broader biosimilar adoption. However, the FDA’s approach is evolving, and they may grant interchangeability with scientific justification without separate switching studies. Regulatory inconsistencies extend beyond biosimilars, as batch-to-batch variability in brand-name biologics does not face the same scrutiny as biosimilar approvals. Addressing these regulatory disparities and greater alignment among the FDA, EMA, and WHO may enhance biosimilar adoption. Acceptance of biosimilars may expand treatment accessibility, reduce healthcare costs, and maintain standards of safety and efficacy in managing musculoskeletal diseases.

Caleb Gottlich, Thomas Githens, Alex Drusch et al.

Abstract Background The sacroiliac joints (SIJ) are specialized articulations in the pelvis that allow load transfer between the upper and lower body. Traumatic pelvic disruption often requires surgical fixation of at least one of these joints. Subsequent SIJ pain is associated with asymmetries in joint laxity or stiffness. This pilot study examines SIJ stiffness in patients with intact sacroiliac screw fixation after posterior pelvic ring injuries. This information will prove valuable to informing surgeons about technique efficacy in SIJ injury stabilization. Questions/purposes This pilot study examined SIJ stiffness in patients with intact sacroiliac screw fixation to: (1) establish vibration energy color Doppler imaging (VECDI) SIJ intra-rater reliability; (2) measure SIJ stiffness in subjects following surgical fixation using VECDI; (3) compare stiffness data between post-surgical and healthy control subjects; (4) evaluate the relationship between stiffness data and pain and disability scores. Methods 13 reliability and 19 experimental subjects were tested using VECDI. Subjects were placed into a side-lying position on top of a shaker apparatus that transmitted vibration energy to the pelvic ring while color Doppler images were taken from the bilateral posterior SIJ. One investigator performed SIJ measurements on healthy subjects to establish reliability and then evaluated post SIJ fixation stiffness in experimental subjects at four-weeks (T1) and eight-weeks (T2). Visual analog scales were used to collect subjective pain scores at each time point. Results Healthy subject VECDI values suggested good intra-rater reliability (ICC = 0.819; CI 95% = 0.405–0.945). No significant differences in SIJ stiffness (ΔTU) were observed between healthy and experimental subjects at both time points (p > .05). Pearson correlation coefficients highlighted relationships between current pain at T1 and T2 (p = .004, r = .879), and Oswestry Disability Index (ODI) values at T1 and T2 (p = .003, r = .890). Conclusions Asymmetric laxity through the SIJ can be associated with pain resulting from either trauma or inherent physiologic variations. Prior to this study, the mainstay of evaluation was subjective indexes, such as the ODI. Here we propose VECDI as a potentially objective tool in SIJ assessment. Following surgical fixation necessitated by trauma, fixation using SI screws demonstrated similar stiffness values through the SIJ at four- and eight-weeks post-operatively when compared to healthy controls. Direct inferences regarding VECDI’s exact sensitivity to SIJ dysfunction cannot be concluded from our investigation due to small sample sizes. Future investigations should include a larger sample size to enhance our understanding of stiffness measurements obtained using VECDI, validate the technique, and determine the time-course of healing from SIJ surgical stabilization.

Shinichi Mizuki, Keiko Tanaka, Yoshihiro Miyake et al.

Abstract Background Typical foot deformity patterns of patients with rheumatoid arthritis (RA) include hallux valgus, claw toes, splay foot, flat foot, and hindfoot valgus deformities. However, some patients present deformities that are different from a typical pattern, such as metatarsus primus elevatus, described as dorsal elevation of the first metatarsal in relation to the lesser metatarsals. We speculated that metatarsus primus elevatus might be associated with calcaneal inclination and hindfoot varus alignment; however, studies on the association of hindfoot alignment with metatarsus primus elevatus in patients with RA are limited. Objective To elucidate the impact of hindfoot coronal and sagittal alignment on metatarsus primus elevatus in patients with RA. Methods We performed a retrospective analysis of weight-bearing anteroposterior and lateral radiographs of 58 patients (112 feet) with rheumatoid foot deformities who underwent surgery. The degree of metatarsus primus elevatus (dMPE) was assessed based on the distance between the dorsal cortical bones of the first and second metatarsals, as measured on lateral radiographs. The intermetatarsal angle between the first and second metatarsals (M1M2), calcaneal pitch, and the naviculocuboid (N/C) overlap ratio were assessed. Patients were divided into four subgroups representing dMPE quartiles (Q1–Q4) as closely as possible. Analysis of covariance was used to calculate the adjusted means of the radiographic parameters. Logistic regression was used to assess the association between clinical and radiographic parameters and the risk of being in the highest dMPE quartile (i.e., Q4). Results The median dMPE in patients with RA was 2.0 mm (interquartile range, 0.2–5.4 mm). Analysis after adjusting for sex, age, body mass index, and disease duration revealed that the M1M2 angle and N/C overlap ratio in the Q4 subgroup were significantly smaller than those in the Q1 subgroup (p < 0.01 for both parameters). Only the N/C overlap ratio showed a significant inverse association with the risk of being in Q4 (adjusted odds ratio: 0.94, 95% confidence interval: 0.91–0.97). Conclusion A subset of patients with RA exhibits metatarsus primus elevatus, which is associated with hindfoot alignment. Recognizing this less common deformity pattern is important when planning treatment strategies for the rheumatoid foot.

Lei Gao, Zhipeng Tang, Zhijin Zhang et al.

Abstract Background Osteomyelitis (OM) is a bone disease that can leave people disabled. Eukaryotic translation initiation factor (EIF5A) is involved in cell proliferation, apoptosis, differentiation, and inflammation, but the role of EIF5A in staphylococcus aureus (S. aureus)-infected OM remains unclear. Methods The mRNA and proteins were detected by qRT-PCR and western blot. Cell viability was examined by CCK8 assay. The reactive oxygen species (ROS), malondialdehyde (MDA), ferrous iron (Fe2+), and glutathione (GSH) levels were analyzed using the ROS, MDA, GSH, and Fe2+ detection kits. The levels of tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β), and Interleukin-6 (IL-6) were examined using Enzyme-linked immunosorbent (ELISA) kits. The binding between FOS and promoter of EIF5A was detected by chromatin immunoprecipitation (CHIP) assay. The interaction between EIF5A and Fos proto-oncogene (FOS) was detected by dual-luciferase reporter assay. The diagnostic values of EIF5A and FOS were analyzed with blood of S. aureus-infected OM patients and healthy volunteers by ROC curve. Results The EIF5A was up-regulated in S. aureus-infected OM. EIF5A knockdown promoted cell viability in S. aureus-infected MG-63 cells and reduced ROS, MDA, and Fe2+ levels, and increased GSH levels. Meanwhile, silencing EIF5A could increase expression of glutathione peroxidase 4 (GPX4), and ferritin heavy chain1 (FTH1) and reduce acyl-CoA synthetase long-chain family member 4 (ACSL4) expression, and silencing EIF5A could reduce immune factors (TNF-α, IL-1β, and IL-6) levels. FOS could bind to EIF5A. Silencing FOS promoted cell viability, and increased GSH levels in S. aureus-infected MG-63 cells, but reduced ROS, MDA, and Fe2+ levels. Meanwhile, promoted GPX4 and FTH1 expression, inhibited ACSL4 expression, and reduced immune factor levels in S. aureus-infected MG-63 cells. Interestingly, EIF5A overexpression could weaken the actions. FOS promotes ferroptosis and inflammation via EIF5A in S. aureus-infected MG-63 cells. Besides, the EIF5A and FOS might be potential molecular diagnostic markers in the progression of OM. Conclusion FOS promotes ferroptosis and inflammation via EIF5A in S. aureus-infected OM. This study is first to report the role of FOS and EIF5A in S. aureus-infected OM, but we found that there are still some limitations in our work, such as not covering all possible types of infection, which is the focus of future research.

Xuanyu Chen, Zhangfu Li, Chao Zheng et al.

Abstract Objective This study aims to investigate changes in matrix metalloproteinase (MMP) and tissue inhibitor of metalloproteinase (TIMP) levels in the intervertebral discs of New Zealand white rabbits under simulated overload and microgravity conditions, focusing on the expression of MMP1, MMP3, and TIMP1. The findings aim to provide a theoretical foundation for preventing and delaying lumbar disc degeneration in these environments. Methods Overload was simulated using an animal centrifuge, and microgravity was mimicked through tail suspension. A randomized single-blind method was applied to divide 120 age- and weight-matched New Zealand white rabbits into six groups: control groups (30 d, 60 d, 90 d) and overload/microgravity groups (30 d, 60 d, 90 d), with 20 rabbits per group. The expression of MMP1, MMP3, and TIMP1 in the lumbar intervertebral discs was measured and analyzed using statistical methods, including chi-square tests and t-tests, across different exposure times. Results In the experimental groups, MMP1 and MMP3 expression levels were significantly higher than those in the corresponding control groups at all time points (P < 0.01). MMP1 and MMP3 levels progressively increased with longer exposure durations, showing statistically significant differences (P < 0.01). TIMP1 expression was significantly higher in the 30-day and 60-day experimental groups than in the control group (P < 0.01), but decreased in the 90-day group, indicating a late-stage imbalance in the MMP/TIMP1 ratio. Conclusion Simulated overload and microgravity conditions lead to elevated MMP1, MMP3, and TIMP1 expression in lumbar intervertebral discs, promoting accelerated disc degeneration.

Christos Zavos

Xiangduo Kong, Ananya Rajagopal, Skylar Renee Foust et al.

Jean-Paul Henri Dedam, Matthew Fogel, Elizabeth Fogel

Robert Nims, Daniel R. Palmer, Jordan Kassab et al.

Abstract The mechanosensitive ion channels Transient Receptor Potential Vanilloid 4 (TRPV4) and PIEZO1 transduce physiologic and supraphysiologic magnitudes of mechanical signals in the chondrocyte, respectively. TRPV4 activation promotes chondrogenesis, while PIEZO1 activation by supraphysiologic deformations drives cell death. The mechanisms by which activation of these channels discretely drives changes in gene expression to alter cell behavior remain to be determined. To date, no studies have contrasted the transcriptomic response to activation of these channels nor has any published data attempted to correlate these transcriptomes to alterations in cellular function. This study used RNA sequencing to comprehensively investigate the transcriptomes associated with activation of TRPV4 or PIEZO1, revealing that TRPV4 and PIEZO drive distinct transcriptomes and also exhibit unique co‐regulated clusters of genes. Notably, activation of PIEZO1 through supraphysiologic deformation induced a transient inflammatory profile that overlapped with the interleukin (IL)‐1‐responsive transcriptome and contained genes associated with cartilage degradation and osteoarthritis progression. However, both TRPV4 and PIEZO1 were also shown to elicit anabolic effects. PIEZO1 expression promoted a pro‐chondrogenic transcriptome under unloaded conditions, and daily treatment with PIEZO1 agonist Yoda1 significantly increased sulfated glycosaminoglycan deposition in vitro. These findings emphasize the presence of a broad “mechanome” with distinct effects of TRPV4 and PIEZO1 activation in chondrocytes, suggesting complex roles for PIEZO1 in both the physiologic and pathologic responses of chondrocytes. The identification of transcriptomic profiles unique to or shared by PIEZO1 and TRPV4 (distinct from IL‐1‐induced inflammation) could inform future therapeutic designs targeting these channels for the management and treatment of osteoarthritis.

Min Deng, Woodvine O. Odhiambo, Min Qin et al.

Abstract A comprehensive understanding of the intricate cellular and molecular changes governing the complex interactions between cells within acne lesions is currently lacking. Herein, we analyzed early papules from six subjects with active acne vulgaris, utilizing single-cell and high-resolution spatial RNA sequencing. We observed significant changes in signaling pathways across seven different cell types when comparing lesional skin samples (LSS) to healthy skin samples (HSS). Using CellChat, we constructed an atlas of signaling pathways for the HSS, identifying key signal distributions and cell-specific genes within individual clusters. Further, our comparative analysis revealed changes in 49 signaling pathways across all cell clusters in the LSS— 4 exhibited decreased activity, whereas 45 were upregulated, suggesting that acne significantly alters cellular dynamics. We identified ten molecules, including GRN, IL-13RA1 and SDC1 that were consistently altered in all donors. Subsequently, we focused on the function of GRN and IL-13RA1 in TREM2 macrophages and keratinocytes as these cells participate in inflammation and hyperkeratinization in the early stages of acne development. We evaluated their function in TREM2 macrophages and the HaCaT cell line. We found that GRN increased the expression of proinflammatory cytokines and chemokines, including IL-18, CCL5, and CXCL2 in TREM2 macrophages. Additionally, the activation of IL-13RA1 by IL-13 in HaCaT cells promoted the dysregulation of genes associated with hyperkeratinization, including KRT17, KRT16, and FLG. These findings suggest that modulating the GRN-SORT1 and IL-13-IL-13RA1 signaling pathways could be a promising approach for developing new acne treatments.

Joo Han Oh, Jaewon Choi, Dong Ho Lee et al.

Longhao Chen, Xingchen Zhou, Chao Yang et al.

Abstract Background Juvenile idiopathic arthritis (JIA) is a type of chronic childhood arthritis with complex pathogenesis. Immunological studies have shown that JIA is an acquired self-inflammatory disease, involving a variety of immune cells, and it is also affected by genetic and environmental susceptibility. However, the precise causative relationship between the phenotype of immune cells and JIA remains unclear to date. The objective of our study is to approach this inquiry from a genetic perspective, employing a method of genetic association analysis to ascertain the causal relationship between immune phenotypes and the onset of JIA. Methods In this study, a two-sample Mendelian randomization (MR) analysis was used to select single nucleotide polymorphisms (SNPs) significantly associated with immune cells as instrumental variables to analyze the bidirectional causal relationship between 731 immune cells and JIA. There were four types of immune features (median fluorescence intensity (MFI), relative cellular (RC), absolute cellular (AC), and morphological parameters (MP)). Finally, the heterogeneity and horizontal reproducibility of the results were verified by sensitivity analysis, which ensured more robust results. Results We found that CD3 on CM CD8br was causally associated with JIA at the level of 0.05 significant difference (95% CI = 0.630 ~ 0.847, P = 3.33 × 10−5, PFDR = 0.024). At the significance level of 0.20, two immunophenotypes were causally associated with JIA, namely: HLA DR on CD14+ CD16- monocyte (95% CI = 0.633 ~ 0.884, P = 6.83 × 10–4, PFDR = 0.16) and HLA DR on CD14+ monocyte (95% CI = 0.627 ~ 0.882, P = 6.9 × 10−4, PFDR = 0.16). Conclusion Our study assessed the causal effect of immune cells on JIA from a genetic perspective. These findings emphasize the complex and important role of immune cells in the pathogenesis of JIA and lay a foundation for further study of the pathogenesis of JIA.

David Francisco Poma Vélez, Arturo Xavier Reyes Paredes, Santiago Andrés Ludeña Poma

La enfermedad de Still del adulto (ESA) es una condición médica poco frecuente con raras complicaciones graves; sin embargo, aún no se conocen con claridad sus factores de riesgo, sus factores pronósticos, ni los aspectos asociados a las recaídas y a la refractariedad a esteroides en individuos con esta condición. Afecta a adultos jóvenes (promedio. La ESA se caracteriza por la tríada fiebre, artralgias/artritis y brote cutáneo; sin embargo, su presentación clínica puede variar. Los criterios diagnósticos más utilizados fueron propuestos por Yamaguchi (1992), de los cuales se requiere el cumplimento de mínimo 5 y que 2 de estos sean mayores. Los criterios mayores son: fiebre >39°C con duración ≥1 semana, artralgia o artritis por al menos 2 semanas, brote y leucocitosis >10 000/mm3 con más de 80% de células polimorfonucleares. Los criterios menores son: odinofagia, aparición reciente de linfadenopatía significativa, hepatomegalia o esplenomegalia, pruebas de función hepática anormales y pruebas negativas para anticuerpos antinucleares (ANA) o factor reumatoide. Otro hallazgo común es la hiperferritinemia. Su diagnóstico diferencial se lo realiza con infecciones, malignidad y enfermedades reumáticas. El pronóstico de la ESA es favorable, con una tasa de mortalidad específica estimada del 1-3%, siendo el Síndrome de Activación Macrofágica su principal complicación, la prevalencia oscila entre el 10 y el 15% y se asocia a una alta tasa de mortalidad.

Petra Grahn, Tiina Remes, Reetta Kivisaari et al.

Abstract Background Childhood brain tumor (BT) survivors have an increased risk of treatment-related late effects, which can reduce health-related quality of life and increase morbidity. This study aimed to investigate lumbar disc degeneration in magnetic resonance imaging (MRI) in adult survivors of radiotherapy-treated childhood BT compared to age and sex-matched population controls. Methods In this cross-sectional comparative study, 127 survivors were identified from hospital registries. After a mean follow-up of 20.7 years (range 5–33.1), 67 survivors (mean age 28.4, range 16.2–43.5) were investigated with MRI and compared to 75 sex-matched population-based controls. Evaluated MRI phenotypes included Pfirrmann grading, , intervertebral disc protrusions, extrusions, and high-intensity-zone-lesions (HIZ). Groups were also compared for known risk factors of lumbar intervertebral disc (IVD) degeneration. Results Childhood BT survivors had higher Pfirrmann grades than controls at all lumbar levels (all p < 0.001). Lumbar disc protrusions at L4-5 (p = 0.02) and extrusions at L3-4 (p = 0.04), L4-5 (p = 0.004), and L5-S1 (p = 0.01) were significantly more common in the BT group compared to the control. The survivor cohort also had significantly more HIZ-lesons than the controls (n=13 and n=1, p=0.003). Age at diagnosis was associated with lower degree of IVD degeneration (p < 0.01). Blood pressure correlated with IVD degeneration (P < 0.05). Conclusions Signs of early disc degeneration related to tumor treatment can be seen in the IVDs of survivors. Disc degeneration was more severe in children treated in adolescence.

Pengju Zhao, Ke Li, Peter C. Coyte

Abstract This paper used two waves (2016 and 2018) of longitudinal data from the China Families Panel Survey (CFPS) to analyze the economic impact of Non-communicable chronic diseases (NCDs) on individual earned income using propensity score matching and difference in difference (PSM-DID) methods to control for potential confounding. The occurrence of a NCDs was associated with a significant decrease in earned income by 19.2% (P = 0.002, t = 3.75). The reasons for this decrease include: a lower labour force participation rate; lower weekly hours worked; and a lower average hourly wage. After holding labour market behaviours constant, different types of NCDs have different impacts on earned income. Musculoskeletal diseases have the greatest negative impact, accounting for a 21.5% decrease in individual earned income (p < 0.0001, t = −7.84), while digestive system diseases have the smallest impact accounting for a 6.9% decrease in earned income (p = 0.012, t = −2.52).

Simon Hwang, MD, Javier Ardebol, MD, Kassem Ghayyad, MD et al.

Background: Surgeon visual estimation of shoulder range of motion (ROM) is commonplace in the outpatient office setting and routinely reported in clinical research, but the reliability and accuracy of this practice remain unclear. The purpose of this study is to establish the reliability and accuracy of remote visual estimation of shoulder ROM in healthy volunteers and symptomatic patients among a large group of shoulder surgeons. Our hypothesis is that remote visual estimation would be reliable and accurate compared with the digital goniometer method. Methods: Fifty shoulder surgeon members of the PacWest Shoulder and Elbow Society independently determined the active shoulder forward flexion (FF), internal rotation at 90° abduction (IR90), external rotation at 90° abduction, external rotation at the side , and maximal spinal level reached with internal rotation (IRspine) through visual estimation of video recordings taken from 10 healthy volunteers and 10 symptomatic patients. Variations in measurements were quantified using the interobserver reliability through calculation of the intraclass correlation coefficient. Accuracy was determined through comparison with digital goniometer measurements obtained with an on-screen protractor application using Bland–Altman mean differences and 95% limits of agreement. Results: The interobserver reliability among examiners showed moderate to excellent correlation, with intraclass correlation coefficient ranging from 0.768 to 0.928 for the healthy volunteers and 0.739 to 0.878 for the symptomatic patients. Accuracy was limited, with upper limits of agreement exceeding the established minimal clinically important differences (MCIDs) for FF (20° vs. MCID of 14°) and IR90 (25° vs. 18°) in the healthy volunteers and for FF (33° vs. 16°), external rotation at 90° abduction (21° vs. 18°), and IR90 (31° vs. 20°) in the symptomatic patients. Conclusion: Despite generally high intersurgeon reliability in the visual estimation of shoulder ROM, there was questionable accuracy when compared to digital goniometer measurements,with measurement errors often exceeding established MCID values. Given the potential implications for the clinical response to treatment and the significance of research findings, the adoption of validated instruments to measure ROM and the standardization of examination procedures should be considered.

Huijing He, Li Pan, Dingming Wang et al.

Abstract Background Hand grip strength (HGS) is a powerful indicator of sarcopenia and other adverse health outcomes. Normative values for HGS for general Chinese people with a broad age spectrum are lacking. This study aims to establish normative values of HGS and explore the correlations between HGS and body composition among unselected people aged 8–80 in China. Methods From 2012 to 2017, 39 655 participants aged 8–80 years in the China National Health Survey were included. Absolute HGS was measured using a Jamar dynamometer. The relative HGS was normalized by body mass index. Body composition indexes included body mass index, body fat percentage, muscle mass, fat mass index (FMI) and muscle mass index (MMI). Sex‐specific smoothed centile tables for the P1, P5, P25, P50, P75, P95 and P99 centiles of HGS and body composition were generated using lambda‐mu‐sigma method. The correlations between muscle strength and body composition were estimated by partial Spearman correlation analysis. Results The median values (25th and 75th percentile) of HGS in boys and girls (8–19 years old) were 22 (14, 34) kg and 18 (12, 22) kg, respectively; in men and women aged 20–80 were 39 (33, 44) kg and 24 (20, 27) kg, respectively. Values of upper and lower HGS across ages had three periods: an increase to a peak in the 20 s in men (with the 5th and 95th values of 30 and 55 kg, respectively) and 30 s in women (with the 5th and 95th values of 18 and 34 kg, respectively), preservation through midlife (20s–40 s), and then a decline after their 50 s. The lowest HGS values in both sexes were in the 70‐ to 80‐year‐old group, with the 5th and 95th percentile values of 16 and 40 kg in men, and 10 and 25 kg in women. There were substantial sex differences in body composition in the life course (all P values <0.001). In ageing, the decrease of muscle strength was faster than that of muscle mass in both sexes. The correlations between muscle mass and HGS were most robust than other correlations, especially in women (0.68 vs. 0.50), children and adolescents. Conclusions Our study established the age‐ and sex‐specific percentile reference values for hand grip strength in an unselected Chinese population across a broad age‐spectrum. The rich data can facilitate the practical appraisal of muscle strength and promote early prediction of sarcopenia and other impairments associated with neuromuscular disorders.

Kyung-Hyun Park-Min, Joseph Lorenzo

Rongjie Bai, Zhanhua Qian, Huili Zhan

Mengyu Wang, Jia Liu, Lingcui Meng et al.

Abstract Background Lower back pain and stiffness are the typical symptoms of ankylosing spondylitis (AS). In this study, muscle mass was assessed by muscle density, mechanical elasticity, and area. We investigated the characteristics of lumbar paraspinal-muscle (PSM) mass using muscle ultrasound shear-wave elastography (SWE), as well as the validity of this method for identifying patients with AS. Methods We recruited a representative cohort of 30 AS patients, and 27 healthy volunteers who were age- and sex-matched to the patient study group, investigated the Young’s modulus (YM), cross-sectional area (CSA) and thickness of lumbar multifidus (LM) muscle using SWE. This study did not need to be randomized. Data were collected at the department of ultrasonography of Guangdong Provincial Hospital of Chinese Medicine. We analyzed the data using SPSS version 18.0 (IBM Corp, Armonk, NY, USA). Normal distribution was evaluated by the Shapiro–Wilk test and Q–Q plots. Demographic and baseline data will be analyzed with standard descriptive statistics. Data will be presented as the mean ± standard deviation (SD). Non-normally distributed data are presented as medians with interquartile ranges (IQR). Results Young’s modulus (YM) of SWE in AS patients was significantly higher than that in volunteers. Percentage change in lumbar multifidus (LM) muscle cross-sectional area (CSA) and thickness were significantly lower in AS patients than in healthy volunteers on the left side of the body. Correlation analysis showed a positive correlation between percentage change in CSA and thickness in both volunteers and AS patients. In AS patients, YM was negatively correlated with percentage change of CSA and thickness on the right side, while increased disease duration in AS was associated with increased YM on the left. Conclusion AS patients showed reductions in LM muscle mass and function as the disease progressed, SWE could reflect these changes well. Trial registration. Chinese Clinical Trial Registry, ChiCTR2000031476. Registered 02/04/2020. http://www.chictr.org.cn/index.aspx .