Journal of Orthopaedic Research®最新文献

{"title":"Type III Collagen Promotes a Pro-Fibrotic Microenvironment for In Vitro Tendon Healing Microphysiological Systems","authors":"Victor Z. Zhang,&nbsp;Tresa Elias,&nbsp;Mariana Rodriguez,&nbsp;Elio Abbondanzieri,&nbsp;Edward Brown,&nbsp;James L. McGrath,&nbsp;Hani A. Awad","doi":"10.1002/jor.70192","DOIUrl":"10.1002/jor.70192","url":null,"abstract":"<div>\u0000 \u0000 <p>Microphysiological systems of tendon healing, or Tendon-on-Chips, are promising platforms for studying scarring and fibrotic repair and can be relevant for the development of novel anti-fibrotic therapeutics. Effective fibrosis models must accurately recreate the myofibroblast microenvironment of signals that modulate their activation and drive peritendinous adhesions. These include not only the cellular interactions between resident tendon cells and proliferating immune and endothelial cells, but importantly, the dynamic extracellular matrix changes. In this study, we explore the extracellular matrix of healing tendon by investigating the role of type III collagen in inflammatory fibrosis. To address this, we evaluated the structural and biological effects of increased type III collagen ratio in an in vitro hydrogel model. Collagen hydrogels with 20% type III and 80% type I collagen had smaller fibrils and pores compared to those with 5% type III and 95% type I collagen. While these structural differences did not significantly alter viscoelastic or diffusive transport properties, higher type III collagen led to significant cellular effects that correlate with known in vivo features. Activated myofibroblasts were less contractile in high type III collagen hydrogels. Monocytes exhibited significantly hindered migration in a chemotaxis experiment. Furthermore, endothelial cells demonstrated increased angiogenic sprouting and microvascular network formation when suspended in high type III collagen hydrogels. These findings demonstrate that type III collagen precipitates a vascular fibrotic phenotype in injured tendons. Clinical Significance: Use of type III collagen to simulate fibrotic extracellular matrix will increase the accuracy of human-relevant tendon microphysiological systems for improved antifibrotic drug development.</p>\u0000 </div>","PeriodicalId":16650,"journal":{"name":"Journal of Orthopaedic Research®","volume":"44 4","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-04-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147627963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Murine Progeria Model Exhibits Delayed Fracture Healing With Senescent Phenotype and Dysregulated Immune Response","authors":"Victoria R. Duke,&nbsp;Marc J. Philippon Jr.,&nbsp;Dane R. G. Lind,&nbsp;Herbert Kasler,&nbsp;Kohei Yamaura,&nbsp;Matt Huard,&nbsp;Molly Czachor,&nbsp;Justin Hollenbeck,&nbsp;Justin Brown,&nbsp;Alex Garcia,&nbsp;Jacob D. Matityahu,&nbsp;Naomasa Fukase,&nbsp;Ralph S. Marcucio,&nbsp;Anna-Laura Nelson,&nbsp;William S. Hambright,&nbsp;Dustin M. Snapper,&nbsp;Johnny Huard,&nbsp;Chelsea S. Bahney","doi":"10.1002/jor.70193","DOIUrl":"10.1002/jor.70193","url":null,"abstract":"<p>An estimated 189 million bone fractures occurred in 2019 making it one of the most globally prevalent injuries. Delayed union or nonunion occurs in up to 15% of normal fractures with higher rates in aged individuals. Preclinical testing supports the translation of novel strategies to promote improved fracture repair, but there is a paucity of small animal models that recapitulate delayed fracture healing. Here, we evaluated the <i>Zmpste24</i>⁻^/⁻ (Z24⁻^/⁻) murine model of Hutchinson-Gilford progeria syndrome as a model of delayed fracture healing. Leveraging the previously characterized Z24⁻^/⁻ phenotype of genomic instability, epigenetic changes, and fragility, we hypothesize that progeria mice will present with significantly delayed fracture healing relative to age-matched wild type (WT) controls. Mice received intramedullary-fixed tibia fractures with healing and immunosenescence evaluated throughout repair. Z24⁻^/⁻ mice demonstrated significantly delayed healing with smaller fracture calli containing more cartilage and less bone relative to WT mice. The fracture healing phenotype of the Z24⁻^/⁻ phenocopied naturally aged mice with increased systemic senescence noted in animals relative to adult WT. Unlike naturally aged mice, Z24⁻^/⁻ also presented with frail bones. Z24⁻^/⁻ showed a dysregulated immune composition, with decreased lymphopoiesis, increased myelopoiesis and neutrophil accumulation. Aspects of the macrophage phenotype in Z24⁻^/⁻ reflected changes in natural aging, but with different systemic T cell responses. Given the Z24⁻^/⁻ progeria mouse model demonstrates the delayed fracture healing phenotype of naturally aged animal at 3 rather than 20 months of age, we suggest this model provides an accelerated model of age-related delayed fracture healing.</p>","PeriodicalId":16650,"journal":{"name":"Journal of Orthopaedic Research®","volume":"44 4","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-04-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13049502/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147616110","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Supraspinatus Tendon Thickness Is Associated With Collagen Disorganization in Symptomatic and Asymptomatic Shoulders of Individuals With Unilateral Rotator Cuff Tendinopathy","authors":"M. Chris Zipser,&nbsp;Oscar Vila-Dieguez,&nbsp;Sebastian Klich,&nbsp;Greg Bashford,&nbsp;Kira Chow,&nbsp;Lori A. Michener","doi":"10.1002/jor.70200","DOIUrl":"10.1002/jor.70200","url":null,"abstract":"<p>Rotator cuff (RC) tendinopathy is a common source of shoulder pain and is frequently linked to structural changes in the supraspinatus tendon of greater thickness and disrupted collagen organization. This study aimed to characterize differences in tendon thickness and collagen organization between individuals with unilateral symptomatic RC tendinopathy, their contralateral asymptomatic shoulder, and asymptomatic controls, and to examine the relationship between thickness (macro-morphology) and collagen organization (micro-morphology). This is a cross-sectional observational study of 64 participants diagnosed with RC tendinopathy compared to 64 asymptomatic controls. On ultrasound imaging of the tendon, thickness was measured, and collagen organization was quantified via spatial frequency analysis of peak spatial frequency radius (PSFR). Compared to controls, individuals with RC tendinopathy showed significantly greater tendon thickness on the involved side (4.3 ± 0.7 vs. 3.9 ± 0.5 mm, <i>p</i> = 0.0097), but no differences in PSFR. Participants with RC tendinopathy showed no significant differences between sides in tendon thickness or PSFR. In the RC tendinopathy group, tendon thickness and PSFR were inversely correlated on both the involved (<i>r</i> = −0.24, <i>p</i> = 0.060) and uninvolved (<i>r</i> = −0.32, <i>p</i> = 0.01) sides, indicating that increased tendon thickness was associated with decreased collagen organization—an association not observed in controls. Findings suggest tendon thickness reflects maladaptive structure in RC tendinopathy, and collagen organization alone may not sufficiently identify tendon pathology. The relationship between tendon thickness and collagen disorganization in RC tendinopathy indicates that tendon maladaptation differs from adaptive hypertrophy in healthy shoulders.</p><p><b>Statement of Clinical Significance:</b> Combined evaluation of tendon hypertrophy and collagen organization can enhance structural characterization in those with tendinopathy.</p>","PeriodicalId":16650,"journal":{"name":"Journal of Orthopaedic Research®","volume":"44 4","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13047412/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147609158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biomechanical Comparison of Single-, Double-, and Triple-Screw Fixation for Tibial Eminence Fractures: A Skeletally Immature Porcine Cadaveric Study","authors":"Il-Kyu Park,&nbsp;Sinje Kim,&nbsp;Seonjin Shin,&nbsp;Chang-Hoon Jeong,&nbsp;Dai-Soon Kwak","doi":"10.1002/jor.70194","DOIUrl":"10.1002/jor.70194","url":null,"abstract":"<div>\u0000 \u0000 <p>This study uses a porcine cadaveric model to biomechanically compare the single-, double-, and triple-screw fixation techniques for tibial eminence fractures. Eighty porcine tibiae were divided into eight groups (<i>n</i> = 10 each): intact control, pull-out suture fixation, one 4.0-mm half-threaded screw, one 4.0-mm full-threaded screw, one 4.5-mm screw, two 4.0-mm parallel screws, two 4.0-mm divergent screws, and three 4.0-mm screws. Standardized fractures were created and fixed according to each protocol. The specimens underwent cyclic followed by load-to-failure testing. Maximum failure load and cyclic displacement were compared. The intact specimens demonstrated significantly higher ultimate load (1059.44 ± 311.84 N) than all fixation groups (<i>p</i> &lt; 0.001). Among the fixation methods, the three-screw configuration withstood the highest load (442.10 ± 123.42 N), followed by the two-screw divergent (392.26 ± 47.63 N) and two-screw parallel (329.33 ± 56.30 N) configurations. The two-screw divergent configuration provided significantly greater strength than the parallel orientation (<i>p</i> &lt; 0.050). Full-threaded screws demonstrated significantly less cyclic displacement (1.05 ± 0.49 mm) than half-threaded screws (2.21 ± 0.49 mm, <i>p</i> &lt; 0.001). The pull-out suture showed significantly greater displacement (3.25 ± 1.07 mm) than all screw fixations (<i>p</i> &lt; 0.050), yet achieved a comparable ultimate failure load (397.82 ± 126.35 N), indicating that the primary advantage of screw fixation lies in cyclic stability rather than ultimate strength. Although three-screw fixation yielded the highest absolute failure load, the two-screw divergent configuration offered comparable strength (<i>p</i> = 0.571), representing a practical alternative. Screw number, orientation, and thread design significantly influence fixation stability in tibial eminence fractures.</p>\u0000 </div>","PeriodicalId":16650,"journal":{"name":"Journal of Orthopaedic Research®","volume":"44 4","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147609014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Metal Fatigue Fracture After Revision Total Knee Arthroplasty: A Retrieval Analysis","authors":"Michael A. Kurtz,&nbsp;Jeremy L. Gilbert,&nbsp;Aarti A. Shenoy,&nbsp;Gregg R. Klein,&nbsp;Arthur L. Malkani,&nbsp;Steven M. Kurtz","doi":"10.1002/jor.70198","DOIUrl":"10.1002/jor.70198","url":null,"abstract":"<p>Most revision total knee arthroplasty patients experience excellent clinical outcomes. However, case studies document rare occurrences of metal component fractures promoted by the high cycles and low stresses that occur during daily use. <i>In vivo</i>, the mechanism that initiates metal fatigue fracture remains unclear. To address this gap, we collected implants from two retrieval programs. We asked: (1) what is the role of implant fixation in promoting fatigue fracture? (2) within modular junctions, what damage modes are associated with crack initiation? (3) how do equiaxed Ti-6Al-4V and wrought CoCrMo microstructures influence crack propagation? First, we compared clinical data for <i>n</i> = 8 fracture and <i>n</i> = 489 stemmed revision patients. Then, we performed retrieval analysis, combining radiographs with scanning electron microscopy and X-ray photoelectron spectroscopy. We found no differences in weight (<i>p</i> = 0.07) or implantation time (<i>p</i> = 0.10) when comparing revision and fracture cohorts. Radiographs of fractured components showed insufficient metaphyseal fixation at or near the stem's modular junction. At the taper interface, we identified Ti-6Al-4V thread wear and CoCrMo pitting. Sectioning near a Ti-6Al-4V crack initiation site revealed an oxidized interface and an intergranular corrosion attack. On the free surface, TiO increased (<i>p</i> &lt; 0.0001) and TiO₂ decreased (<i>p</i> &lt; 0.0001) after 20 min of sputter time. Fatigue cracks propagated through equiaxed Ti-6Al-4V and wrought CoCrMo grains. These data support a hypothesized mechanism where insufficient implant fixation with bone or cement promotes localized damage accumulation within the modular junction, fatigue crack initiation and subsequent fracture.</p>","PeriodicalId":16650,"journal":{"name":"Journal of Orthopaedic Research®","volume":"44 4","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13047420/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147609101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biomechanical Stability of Tibia Plateau Fracture Treatment: Conventional vs. Finite Element-Based Preoperative Planning","authors":"Sabrina Sandriesser,&nbsp;Robert Pätzold,&nbsp;Simon Comtesse,&nbsp;Lea Sommerhalder,&nbsp;Thomas Zumbrunn,&nbsp;Arvind von Keudell,&nbsp;Benjamin Stäudle,&nbsp;Peter Augat","doi":"10.1002/jor.70188","DOIUrl":"10.1002/jor.70188","url":null,"abstract":"<p>Tibial plateau fractures are complex injuries requiring anatomical reduction and stable fixation to restore joint congruency and function. Digital tools, including CT reconstructions, computer-assisted implant planning, and finite element (FE) modeling, have the potential to improve fixation strategies. This experimental study investigated whether FE-based preoperative planning enhances the stability of tibial plateau fracture fixation compared with conventional planning, assessing construct stiffness, load to failure, and fracture stability under physiologic loading. Twelve human cadaveric lower limbs (78 ± 10 years) with induced Schatzker IV fractures were randomized to conventional (<i>n</i> = 6) or FE-based planning (<i>n</i> = 6). In the FE group, fragment reduction, screw trajectories, and implant positioning were optimized via computational modeling and guided intraoperatively by individual targeting guides. Conventional planning used standard CT visualization. All specimens were fixed using a medial locking plate and tested under axial loading, including stiffness measurement and progressively increasing cyclic loading until failure. Plate and screw positioning did not clearly differ between approaches, however FE-based planning promoted more consistent locking screw utilization and more frequent individual screw usage. FE-based planning yielded higher load to failure (1050 ± 535 N vs. 442 ± 226 N, <i>p</i> = 0.041), more cycles to failure (10,100 ± 5400 vs. 4100 ± 2400; <i>p</i> = 0.046), and more symmetrical construct stiffness. After adjustment for anatomical variations, differences in failure load were no longer statistically significant. Tibial plateau widening during loading was comparable between groups. These findings suggest that FE-based planning can enhance construct stability and reduce fixation asymmetry. Further clinical validation is needed to determine whether these benefits translate into improved outcomes.</p>","PeriodicalId":16650,"journal":{"name":"Journal of Orthopaedic Research®","volume":"44 4","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13045867/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147592883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Machine Learning Better Predicts Mortality in Patients Undergoing Revision Total Hip Arthroplasty for Periprosthetic Joint Infection","authors":"Nora Galoustian,&nbsp;Jeffrey Balian,&nbsp;Christopher David Hamad,&nbsp;Armin Alipour,&nbsp;Peyman Benharash,&nbsp;Alexander B. Christ,&nbsp;Alexandra Stavrakis","doi":"10.1002/jor.70197","DOIUrl":"10.1002/jor.70197","url":null,"abstract":"<div>\u0000 \u0000 <p>Periprosthetic joint infection (PJI) following total hip arthroplasty (THA) is associated with a 25% 5-year mortality. Synthetic Minority Oversampling Technique (SMOTE) is a novel machine learning technique used in other surgical specialties to better predict outcomes, but has never been utilized in the field of orthopedics. This is the first study utilizing machine learning (ML) and SMOTE to predict the greatest risk factors for mortality following revision THA for PJI. This retrospective study utilized the Nationwide Readmissions Database to identify adult patients undergoing revision THA for PJI. Model performance was assessed using AUROC, Brier score, and F1 score, with SHapley Additive exPlanation (SHAP) analysis identifying key predictors. Among 19,099 patients undergoing revision THA for PJI, there was a 0.8% mortality rate. Logistic regression (AUROC 0.855) and gradient boosting (AUROC 0.862) outperformed random forest (AUROC 0.765), with gradient boosting demonstrating the highest F1 score (0.257). Following the application SMOTE, all models demonstrated improved AUROC, model calibration, and enhanced F1. SHAP analysis identified fluid and electrolyte disorders, advancing age, and cardiac arrhythmia as key predictors of mortality. This study is the first in the field of orthopedics to utilize SMOTE and subsequently introduces a novel, streamlined risk score that identifies high-risk patients undergoing revision THA for PJI. Fluid and electrolyte abnormalities were the strongest predictors of mortality. Given the established link between high-dose antibiotic-loaded bone cement spacers and calcium sulfate antibiotic impregnated beads with AKI and subsequent electrolyte disturbances, optimizing electrolyte levels perioperatively may be a mortality-reducing intervention.</p></div>","PeriodicalId":16650,"journal":{"name":"Journal of Orthopaedic Research®","volume":"44 4","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147609017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Recombinant Human Amelogenin Protein Enhances Healing of Osteochondral Injury in a Goat Model","authors":"Omer Helwa-Shalom,&nbsp;Hani Nevo,&nbsp;Tarek Nasrawy,&nbsp;Masha Galiner,&nbsp;Azraq Yusef,&nbsp;Keren Ben-David,&nbsp;Shany Ivon Markowitz,&nbsp;Yechiel N. Gellman,&nbsp;Shaul Beyth,&nbsp;Hagit Sacks,&nbsp;Anat Blumenfeld,&nbsp;Amir Haze","doi":"10.1002/jor.70190","DOIUrl":"10.1002/jor.70190","url":null,"abstract":"<p>Osteochondral injuries are common, painful, and lack natural healing abilities. Previous studies demonstrated that recombinant human amelogenin promotes osteochondral repair in rat knee injuries, including improved defect filling and formation of hyaline cartilage. Here, we aimed to evaluate the efficacy and safety of Remelix®, a novel recombinant human amelogenin–based product, in a large animal goat model. Acute osteochondral injuries were created in the weight-bearing region of the medial femoral condyle in thirteen goats. Seven goats received Remelix® at a protein concentration of 0.5 mg/mL, with the contralateral knee applied with PX 407 carrier alone. An additional six goats received Remelix® at 0.25 mg/mL, while contralateral knees were treated with normal saline. Potential adverse effects, along with evaluation of osteochondral healing were assessed. Healing was assessed 24 weeks post-treatment using magnetic resonance imaging (MRI), macroscopic evaluation, and histological and immunohistochemical analyses. No adverse effects were observed. Both Remelix® concentrations resulted in substantial healing of cartilage and subchondral bone. Histological analyses demonstrated improved tidemark formation, predominantly hyaline cartilage filling in the deeper layers of the defect with extension toward the superficial zone, and reduced subchondral bone abnormalities. MRI and macroscopic evaluations revealed a continuous repair surface with good integration at the defect margins. In contrast, PX 407 and saline-treated control knees exhibited inferior repair, characterized by mainly fibrous cartilage, heterogeneous MRI signal intensity, and lower histological scores. Overall, Remelix® substantially improved osteochondral healing in a goat model without observable adverse effects, supporting its potential for further evaluation in human clinical studies.</p>","PeriodicalId":16650,"journal":{"name":"Journal of Orthopaedic Research®","volume":"44 4","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13045869/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147592850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"High-Frequency Quantitative Ultrasound Parameters Correlate With Microstructural Properties in a Murine Collagenase Model of Patellar Tendinopathy","authors":"Hirotaka Iura,&nbsp;Cameron Hoerig,&nbsp;Krishna Pedaprolu,&nbsp;Matthew R. Covello,&nbsp;Yuki Suzuki,&nbsp;Ping-Chun Yeh,&nbsp;Samuel J. E. Green,&nbsp;Chia-Hung Hung,&nbsp;Daniel M. Markowitz,&nbsp;Hugo Stern,&nbsp;Camila B. Carballo,&nbsp;Scott A. Rodeo,&nbsp;Jonathan Mamou,&nbsp;Claire D. Eliasberg","doi":"10.1002/jor.70185","DOIUrl":"10.1002/jor.70185","url":null,"abstract":"<div>\u0000 \u0000 <p>High-frequency quantitative ultrasound (QUS) offers a promising approach to characterize soft tissue microstructure ex vivo. In this study, we evaluated its ability to detect histological tendon changes in a murine model of patellar tendinopathy. Collagenase was injected into the patellar tendon of C57BL/6 J mice to induce tendinopathy. Tendons were scanned ex vivo using a 60-MHz transducer to acquire radiofrequency (RF) ultrasound echo data. QUS parameters based on envelope statistics and backscatter coefficient measurements were computed from the RF data. Additionally, tendon thickness was measured from the B-mode images. QUS parameters were compared between control and collagenase-injected groups. Histological sections were evaluated using a modified Movin score. Significant differences were observed in QUS parameters effective scatterer diameter (ESD), the Homodyned-K parameter <span></span><math>\u0000 <semantics>\u0000 <mrow>\u0000 \u0000 <mrow>\u0000 <mi>α</mi>\u0000 </mrow>\u0000 </mrow>\u0000 <annotation> $alpha $</annotation>\u0000 </semantics></math>, and thickness between control and collagenase-injected groups (<i>p</i> &lt; 0.05 for all). ESD and thickness correlated with histological scores (<i>R</i> = 0.50, <i>p</i> &lt; 0.001 for both), and receiver operating characteristic analyses showed high classification accuracy (AUC = 0.82–0.89). These findings indicate that QUS parameters are sensitive to pathological alterations in tendon microstructure and may serve as surrogate markers of structural integrity. As a rapid, cost-effective, and portable imaging modality, QUS holds strong potential for longitudinal monitoring of tendinopathy and evaluating treatment response in both animal models and clinical settings. Statement of Clinical Significance: QUS parameters detected tendon microstructural changes, indicating potential for non-invasive longitudinal monitoring, although limited here to post-mortem imaging.</p></div>","PeriodicalId":16650,"journal":{"name":"Journal of Orthopaedic Research®","volume":"44 4","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147592797","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of Humeral Head Versus Iliac Crest Bone Marrow Aspirate Concentrate in Patients Undergoing Arthroscopic Rotator Cuff Repair.","authors":"Camila B Carballo, Michael Schär, Claire D Eliasberg, Erin R Leatherman, Joseph T Nguyen, John T Cavanaugh, Liang Ying, Sergei Rudchenko, Hollis Potter, Russell Warren, Scott A Rodeo","doi":"10.1002/jor.70211","DOIUrl":"https://doi.org/10.1002/jor.70211","url":null,"abstract":"<p><p>The purpose of this exploratory pilot study was to compare the composition of humeral head (HH) and iliac crest (IC) bone marrow aspirates (BMA) and establish a framework for evaluating bone marrow aspirate concentrate (BMAC) in arthroscopic rotator cuff repair (RCR). Fifteen patients (mean age of 60, range: 41-74) with full-thickness RC tears underwent arthroscopic RCR with BM aspiration (30 mL) from both the HH and IC. Mononuclear cells (MNCs) before and after concentration, colony-forming units (CFUs), and connective tissue progenitor cells (CTPs) after concentration were quantified. IC BMAC was injected at the site of RCR. A control cohort underwent RCR without BMAC. MRI analysis, dynamometer strength testing, range of motion, and ASES scores were assessed up to 12 months. Pre-centrifugation MNC counts were similar between HH and IC (17.4 vs. 13.4 MNC/mL, p = 0.18). After centrifugation, IC demonstrated higher MNC concentration (64.6 vs. 29.7 MNC/mL, p = 0.014). CFUs did not differ significantly (1896 vs. 1047, p = 0.17). Total CTPs were higher in IC (8338 vs. 3430, p = 0.035), although live CTPs were not significantly different (6013 vs. 2779, p = 0.054). No significant associations were found between the number CTPs or CFUs and tendon healing on MRI. IC yields greater CTPs than HH, supporting its role as a preferred BMA source. However, BMAC augmentation was not associated with measurable differences in tendon healing or clinical outcomes at 12 months, which may be due to the limited sample size. Further studies are needed to refine cell isolation and optimize BMAC protocols for RCR augmentation.</p>","PeriodicalId":16650,"journal":{"name":"Journal of Orthopaedic Research®","volume":"44 4","pages":"e70211"},"PeriodicalIF":2.3,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147774415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}