Journal of Orthopaedic Research®最新文献

{"title":"Associations Between Patient Characteristics and Cartilage T1ρ Relaxation Times Vary Over Time Following Patellar Dislocation","authors":"John J. Elias,&nbsp;Lutul D. Farrow,&nbsp;Richard Lartey,&nbsp;Ahmet Hakan Ok,&nbsp;Mei Li,&nbsp;Mingrui Yang,&nbsp;Carl S. Winalski,&nbsp;Xiaojuan Li","doi":"10.1002/jor.70233","DOIUrl":"10.1002/jor.70233","url":null,"abstract":"<p>The characteristics of patients that promote progressive cartilage degradation following patellar dislocations are not well understood. The study hypothesis is that associations relating cartilage degradation to low BMI, high activity and youth in the early months following patellar dislocation are not exhibited for contralateral knees or a longer time from injury. Quantitative MRI-based evaluation of injured and contralateral knees occurred within 5 months of a unilateral patellar dislocation (baseline evaluation, 36 subjects) and beyond 5 months (follow-up evaluation, 20 subjects). Linear regressions correlated T1ρ relaxation times for regions of patellofemoral and tibiofemoral cartilage against body mass index, age, and activity level. Long relaxation times indicate cartilage degradation. Baseline T1ρ relaxation times were significantly inversely correlated with body mass index throughout patellofemoral cartilage for injured knees (<i>p</i> &lt; 0.001 to 0.03). Similar relationships were identified for all regions of patellar cartilage for contralateral knees (<i>p</i> = 0.011 to 0.015). Injured and contralateral T1ρ relaxation times were also correlated with activity level (positive correlation) and age (inverse correlation) for various regions of cartilage (<i>p</i> &lt; 0.001 to 0.047). The only significant correlations for the follow-up groups related increasing body mass index to long cartilage T1ρ relaxation times for the contralateral medial trochlear groove, femoral condyles, and lateral tibial plateau (<i>p</i> = 0.008 to 0.026). The attributes of a dislocation that determine characteristics influencing cartilage are common to both knees but dissipate over time. A systemic, transient inflammatory response to injury could explain the short-term similarities between injured and contralateral knees following dislocation.</p>","PeriodicalId":16650,"journal":{"name":"Journal of Orthopaedic Research®","volume":"44 6","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jor.70233","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148205185","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":"Relaxation Time Mapping of Early-Stage Osteonecrosis of the Femoral Head: An In Vivo Piglet Model Study","authors":"Casey P. Johnson,&nbsp;Erick O. Buko,&nbsp;Sampada Bhave,&nbsp;Kayla L. Chase,&nbsp;Douglas Albrecht,&nbsp;Alexandra R. Armstrong,&nbsp;Jutta M. Ellermann,&nbsp;Harry K. W. Kim,&nbsp;Ferenc Tóth","doi":"10.1002/jor.70236","DOIUrl":"10.1002/jor.70236","url":null,"abstract":"<p>Quantitative magnetic resonance imaging (MRI) relaxation time mapping techniques may be useful to evaluate early-stage osteonecrosis of the femoral head, particularly in children with Legg–Calvé–Perthes disease (LCPD). The purpose of this study was to assess the sensitivities of T2, T1ρ, adiabatic T1ρ (aT1ρ), and adiabatic T2ρ (aT2ρ) relaxation time mapping to detect early-stage ischemic injury to the secondary ossification center (SOC) of the femoral head in vivo in a piglet model of LCPD. We hypothesized that relaxation times would be increased in the SOCs of ischemic versus contralateral-control femoral heads 1 week following onset of ischemia. Bilateral hips of <i>n</i> = 13 piglets with confirmed, surgically-induced complete ischemia of the SOC were imaged 1 week post-operatively using a clinical 3 T MRI scanner. Median T2 (<i>n</i> = 13), T1ρ (<i>n</i> = 13), aT1ρ (<i>n</i> = 10), and aT2ρ (<i>n</i> = 10) relaxation times were measured for the total SOC, as well as its central and peripheral subregions, and were compared between the ischemic versus control femoral heads using paired <i>t</i>-tests (<i>p</i> &lt; 0.05). All four relaxation times were significantly increased in the ischemic versus control femoral heads, with a more pronounced increase in the peripheral versus central subregion of the SOC. T2 and aT2ρ had the greatest percent increases and effect sizes of the four relaxation times. In conclusion, T2, T1ρ, aT1ρ, and aT2ρ relaxation time mapping techniques are sensitive in detecting ischemic injury to bone marrow of the femoral head in vivo in a piglet model of LCPD at clinical 3 T MRI field strength.</p>","PeriodicalId":16650,"journal":{"name":"Journal of Orthopaedic Research®","volume":"44 6","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jor.70236","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148157051","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":"Inhibition of Sclerostin Protected Against Particle-Induced Osteolysis via Activation of Wnt Signaling and Suppression of Osteoclast Function","authors":"Hiroaki Ido,&nbsp;Yasuhiko Takegami,&nbsp;Yusuke Osawa,&nbsp;Hiroto Funahashi,&nbsp;Keiji Otaka,&nbsp;Shinya Tanaka,&nbsp;Kimihiro Oono,&nbsp;Hiroaki Nakashima,&nbsp;Hiroaki Wake,&nbsp;Shiro Imagama","doi":"10.1002/jor.70231","DOIUrl":"10.1002/jor.70231","url":null,"abstract":"<div>\u0000 \u0000 <p>Periprosthetic osteolysis induced by wear debris remains a leading cause of aseptic loosening after joint arthroplasty, with no established pharmacological treatment. We investigated an anti-sclerostin antibody (Ab-Scl) and elucidated its mechanism of action in cobalt-chromium (CoCr) particle-induced osteolysis. Tartrate-resistant acid phosphatase (TRAP)-tdTomato mice with labeled mature osteoclasts (mOCs) were used. CoCr particles were applied to the calvarial bone, with or without Ab-Scl administration. Intravital two-photon bone imaging, microcomputed tomography (μCT), and histological and immunohistochemical analyses were performed to evaluate osteolysis, osteoclast activity, and β-catenin expression. In vitro assays using RAW264.7-derived osteoclast-like cells were conducted to investigate downstream signaling pathways. μCT analysis revealed that CoCr particles reduced the bone volume–to–tissue volume fraction and trabecular thickness while increasing trabecular separation and the structural model index; conversely, Ab-Scl significantly attenuated osteolytic changes. Histological analysis showed that CoCr exposure increased the eroded surface area and number of TRAP-positive osteoclasts, both of which were significantly decreased by Ab-Scl. Immunohistochemistry demonstrated that CoCr exposure suppressed β-catenin expression on the bone surface, which was restored by Ab-Scl. Intravital two-photon microscopy revealed that CoCr particles reduced mOC motility and increased the acidic resorptive area, whereas Ab-Scl reversed these changes, enhancing motility and suppressing bone resorption. In vitro, RSPO2 enhanced osteoclastic bone resorption, pit formation, and Pyk2 phosphorylation, which were suppressed by PF-562271. Ab-Scl modulated osteoclast function through Wnt/β-catenin-related mechanisms, potentially involving Pyk2-related pathways, thereby suppressing CoCr particle-induced osteolysis. These findings suggest that Ab-Scl is a promising pharmacological strategy for preventing aseptic loosening following joint arthroplasty.</p>\u0000 </div>","PeriodicalId":16650,"journal":{"name":"Journal of Orthopaedic Research®","volume":"44 6","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148163494","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":"METTL14-Mediated RPL13A Expression Regulates Apoptosis and Invasion of Osteosarcoma via the PTEN/PI3K/AKT Signaling Pathway","authors":"Zilong Chen,&nbsp;Yanqi Pan,&nbsp;Yuhang Wei,&nbsp;Yanxiang Tong,&nbsp;Yaguang Li,&nbsp;Guozhong Zhao,&nbsp;Fei Xue,&nbsp;Yanhui Zhao,&nbsp;Chenyang Meng,&nbsp;Wei Feng","doi":"10.1002/jor.70232","DOIUrl":"10.1002/jor.70232","url":null,"abstract":"<div>\u0000 \u0000 <p>Osteosarcoma (OS) is a highly aggressive mesenchymal bone tumor with a dismal prognosis, and its underlying molecular mechanisms remain elusive. Ribosomal protein L13a (RPL13a) contributes to tumorigenesis, while methyltransferase-like 14 (METTL14), a core m⁶A methyltransferase, modulates OS progression via epigenetic regulation. Our prior work identified the PTEN/PI3K/AKT pathway as a key OS regulator. This study aimed to clarify the regulatory interplay among METTL14, RPL13a and PTEN/PI3K/AKT in OS, and verify that METTL14 mediates RPL13a m⁶A modification to regulate PTEN/PI3K/AKT signaling, affecting OS cell proliferation, apoptosis, migration and invasion. METTL14, RPL13a and m⁶A levels were detected in OS cell lines (U2OS, HOS, MG-63) and normal osteoblast hFOB1.19 cells. RPL13a knockdown, PTEN overexpression and METTL14 overexpression models were established in U2OS/HOS cells. M⁶A-RIP-qPCR and MeRIP assays confirmed RPL13a m⁶A modification, with functional (CCK-8, flow cytometry, wound healing, Transwell) and molecular (RT-qPCR, Western blotting) assays performed in triplicate replicates. METTL14 and RPL13a were upregulated in U2OS/HOS cells versus hFOB1.19 (<i>p</i> &lt; 0.05). METTL14 overexpression elevated RPL13a m⁶A modification by ~1.8-fold (<i>p</i> &lt; 0.05); si-RPL13a reduced RPL13a mRNA by &gt; 60% (<i>p</i> &lt; 0.05). RPL13a knockdown promoted apoptosis, inhibited proliferation/migration/invasion, downregulated PTEN and activated PI3K/AKT signaling, partially reversed by PTEN overexpression. METTL14 overexpression upregulated RPL13a/PTEN and suppressed PI3K/AKT activation, abolished by RPL13a knockdown. METTL14 appears to mediate the m6A methylation modification of RPL13a mRNA. Downregulation of RPL13a is associated with reduced PTEN and activated PTEN/PI3K/AKT signaling, which may ultimately contribute to suppressed osteosarcoma cell proliferation, migration, and invasion while promoting apoptosis.</p></div>","PeriodicalId":16650,"journal":{"name":"Journal of Orthopaedic Research®","volume":"44 6","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-06-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148143729","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":"In Vivo Assessment of Distal Femur Fracture Motion via Weightbearing CT.","authors":"William D Lack, William R Ledoux, Nick Entress, William Crutcher, Scott Telfer, Eric Thorhauer","doi":"10.1002/jor.70229","DOIUrl":"10.1002/jor.70229","url":null,"abstract":"<p><p>Distal femur fractures have a significant risk of healing complications, with potentially suboptimal fracture motion. We developed an in vivo method of quantifying fracture motion to support translational research. Five men and one woman (age 48.3 ± 24.9 years; weight 79.8 ± 12.9 kg, mean ± SD) underwent non-weightbearing and weightbearing CT following plate (4) or nail (2) fixation of distal femur fractures (AO/OTA 33) while recording static ground reaction forces. Subject-specific models were generated, coordinate systems were established, and fragment poses were reconstructed to assess motion. Fracture motion was measurable and greater at the medial than the lateral aspects of fractures, with notable axial plane motion. Three-dimensional (3D) displacement (mean ± standard deviation [SD]) was greater at the medial than lateral fracture (4.4 ± 2.6 vs. 3.5 ± 2.6 mm, p = 0.047), including mean proximal-distal displacement at the medial fracture (2.0 ± 3.0 mm) versus lateral fracture (0.8 ± 3.2 mm, p = 0.030), and mean axial plane displacement at the medial (3.5 ± 1.6 mm) versus lateral (2.6 ± 1.6 mm, p = 0.009) fracture. Axial plane displacement was similar to proximal-distal displacement at the medial (p = 0.318) and lateral (p = 0.488) fracture. 3D and axial plane displacement were moderately associated with load, while proximal-distal displacement was minimally associated with load. Weightbearing magnitude only modestly explained intersubject differences in motion. This method allows exploration of relationships between fracture motion, fracture pattern, fixation, loading, and healing.</p>","PeriodicalId":16650,"journal":{"name":"Journal of Orthopaedic Research®","volume":"44 6","pages":"e70229"},"PeriodicalIF":2.4,"publicationDate":"2026-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148015908","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":"","authors":"","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":16650,"journal":{"name":"Journal of Orthopaedic Research®","volume":"44 6","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148095114","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":"","authors":"","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":16650,"journal":{"name":"Journal of Orthopaedic Research®","volume":"44 6","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148092029","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":"","authors":"","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":16650,"journal":{"name":"Journal of Orthopaedic Research®","volume":"44 6","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148092028","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":"","authors":"","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":16650,"journal":{"name":"Journal of Orthopaedic Research®","volume":"44 6","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-05-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148092027","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":"Hip Joint Loading During Walking Is Associated With Cartilage Defect Severity in Young Adult Football Players With Hip/Groin Pain","authors":"Kay M. Crossley,&nbsp;Yi-Chung Lin,&nbsp;Anthony G. Schache,&nbsp;Anne J. Smith,&nbsp;Matthew G. King,&nbsp;Joshua J. Heerey,&nbsp;Rintje Agricola,&nbsp; Sharmila Majumdar,&nbsp;Richard B. Souza,&nbsp;Thomas M. Link,&nbsp;Benjamin F. Mentiplay,&nbsp;Mark J. Scholes,&nbsp;Adam I. Semciw,&nbsp;Peter R. Lawrenson,&nbsp;Joanne L. Kemp,&nbsp;Marcus G. Pandy","doi":"10.1002/jor.70219","DOIUrl":"10.1002/jor.70219","url":null,"abstract":"<p>Understanding factors associated with early hip osteoarthritis (OA) in young active adults may facilitate hip OA prevention. We investigated the cross-sectional association between hip contact force (HCF) during walking and cartilage defect severity, accounting for cam morphology size (alpha angle), hip pain severity, sex, age, and walking speed, in football players with hip/groin pain. One hundred and twenty-one football players (18–50 years; 26 women) with &gt; 6-month hip/groin pain and no radiographic OA underwent MRI and a Dunn 45° radiograph. Outcome: Scoring Hip Osteoarthritis with MRI (SHOMRI) score for cartilage defect severity (0–20), categorized into three SHOMRI groups: (a) SHOMRI = 0; (b) SHOMRI = 1–3; and (c) SHOMRI = 4+. Movement and ground force data were captured whilst participants walked at their self-selected pace. Musculoskeletal modeling was used to calculate HCF for one stride cycle. The exposure variable was HCF impulse (body weight times seconds [BW.s]). Differences in HCF impulse based on SHOMRI group (for the most symptomatic hip) were assessed using linear models, controlling for alpha angle, sex, age, walking speed, hip pain, and contralateral hip pain status. Resultant HCF impulse was significantly higher for participants in the 0 versus 4+ SHOMRI group (mean difference; 95%CI: 0.142BW.s; 0.028–0.256 for swing and 0.106BW.s; 0.029–0.184 for stance) and 0 versus 1–3 SHOMRI group (0.071 BW.s; 0.016–0.125 for swing). Participants with more severe cartilage defects walked with lower hip joint loading, and other variables (e.g., alpha angle size, hip pain severity, age) contributed little to this relationship. Hip joint under-loading could be a possible target for hip OA prevention.</p>","PeriodicalId":16650,"journal":{"name":"Journal of Orthopaedic Research®","volume":"44 5","pages":""},"PeriodicalIF":2.3,"publicationDate":"2026-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13179577/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147959865","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}