Journal of Experimental Orthopaedics最新文献

{"title":"Implementation of an institutional Enhanced Recovery After Surgery (ERAS) pathway is associated with fewer in-hospital falls after total knee arthroplasty","authors":"Judith Ewert,&nbsp;Yizhou Ge,&nbsp;Martin Häner,&nbsp;Jan-Peter Braun,&nbsp;Wolf Petersen","doi":"10.1002/jeo2.70895","DOIUrl":"10.1002/jeo2.70895","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>To evaluate whether implementation of an Enhanced Recovery After Surgery (ERAS)-based perioperative pathway was associated with a lower rate of postoperative in-hospital falls after total knee arthroplasty (TKA).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>This retrospective single-centre before-after study included 314 patients undergoing primary TKA (151 treated before and 163 treated after implementation of an ERAS-based pathway). The documented pathway components included local infiltration analgesia, tranexamic acid, omission of surgical drains and continuous femoral nerve analgesia and physiotherapist-assisted active and passive mobilization on the day of surgery. The primary outcome was an in-hospital fall documented through the institutional incident-reporting system. Secondary outcomes included pain, opioid consumption, range of motion and postoperative complications.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>In-hospital falls occurred in 1 of 163 patients in the ERAS group (0.6%) and 10 of 151 patients in the non-ERAS group (6.6%) (risk ratio, 0.09; 95% confidence interval [CI], 0.01–0.72; <i>p</i> = 0.004), corresponding to an absolute risk reduction of 6.0 percentage points (95% CI, 1.9–11.2 percentage points). Three falls required medical treatment. Pain at rest was comparable, whereas opioid consumption was lower in the ERAS group (<i>p</i> &lt; 0.001). Time to achieve 90° of knee flexion was shorter in the ERAS group (<i>p</i> &lt; 0.001). Postoperative complications occurred in 0 of 163 ERAS patients and 5 of 151 non-ERAS patients (0% vs. 3.3%; <i>p</i> = 0.025).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Implementation of an ERAS-based perioperative pathway was associated with fewer postoperative in-hospital falls after primary TKA. Because the pathway was introduced as a bundle in a retrospective before-after study, causality cannot be established.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Level of Evidence</h3>\u0000 \u0000 <p>Level III, retrospective cohort study.</p>\u0000 </section>\u0000 </div>","PeriodicalId":36909,"journal":{"name":"Journal of Experimental Orthopaedics","volume":"13 3","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13512039/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148833189","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Robotic-assisted simultaneous bilateral total knee arthroplasty was associated with a more favorable perioperative profile than a historical conventional cohort","authors":"Eduardo Poblete,&nbsp;Robert Partarrieu,&nbsp;Fernando Martin,&nbsp;Nicolás Piderit,&nbsp;Andrea Marré,&nbsp;Rafael Calvo,&nbsp;David Figueroa","doi":"10.1002/jeo2.70897","DOIUrl":"10.1002/jeo2.70897","url":null,"abstract":"&lt;div&gt;\u0000 \u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Purpose&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;To compare perioperative, clinical, and functional outcomes between robotic-assisted and conventional simultaneous bilateral total knee arthroplasty in a historical comparative cohort.&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Methods&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;We conducted a retrospective historical comparative cohort study of patients undergoing simultaneous bilateral total knee arthroplasty at a single high-volume arthroplasty centre between March 2013 and July 2025. Patients were stratified into a historical conventional cohort or a computed tomography-based robotic-arm-assisted cohort. Outcomes included post-operative haematocrit, blood transfusion, tourniquet ischaemia time, length of stay, post-operative complications, and Forgotten Joint Score-12 values.&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Results&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;Sixty-two patients were included: 41 in the robotic-assisted group and 21 in the conventional group. Baseline preoperative haematocrit was higher in the robotic cohort. Post-operative haematocrit was higher after robotic-assisted surgery (31.74 ± 4.81% vs. 26.68 ± 4.41%, &lt;i&gt;p&lt;/i&gt; &lt; 0.001), whereas haematocrit drop did not differ significantly (&lt;i&gt;p&lt;/i&gt; = 0.295). The robotic-assisted group had a lower transfusion requirement (14.6% vs. 76.2%, &lt;i&gt;p&lt;/i&gt; &lt; 0.001). After multivariable adjustment, conventional surgery remained associated with increased odds of post-operative transfusion (adjusted odds ratio 20.78, 95% confidence interval 3.19–135.24). Robotic assistance was also associated with shorter tourniquet ischaemia time and hospital stay. Post-operative complications occurred only in the conventional cohort, although the difference was not statistically significant. Forgotten Joint Score-12 values were available for 34 of 62 patients (54.8%) at a median follow-up of 47.9 months and did not differ significantly between groups (81.06 ± 25.76 vs. 74.83 ± 23.86, &lt;i&gt;p&lt;/i&gt; = 0.486).&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Conclusions&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;Robotic-assisted simultaneous bilateral total knee arthroplasty was associated with a more favourable perioperative profile than a historical conventional cohort, particularly regarding transfusion requirement, post-operative haematocrit, tourniquet ischaemia time, and hospital stay. These findings should be interpreted cautiously because of temporal confounding, incomplete functional follow-up, and limited sample size.&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Level of Evidence&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;Level III.&lt;/p&gt;\u0000 &lt;/sec","PeriodicalId":36909,"journal":{"name":"Journal of Experimental Orthopaedics","volume":"13 3","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13510626/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148833177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correction to “Single-stage ACL reconstruction and displaced bucket handle Meniscus repair is associated with lower Meniscus repair failure rates compared to two-stage surgery”","authors":"","doi":"10.1002/jeo2.70746","DOIUrl":"10.1002/jeo2.70746","url":null,"abstract":"<p>Kekki C, Cristiani R, Stålman A, von Essen C. Single-stage ACL reconstruction and displaced bucket handle Meniscus repair is associated with lower Meniscus repair failure rates compared to two-stage surgery. <i>J Exp Orthop</i>. 2025;12(1):e70199. https://doi.org/10.1002/jeo2.70199</p><p>In Table 4, the Hazard ratio listed for the univariate analysis of treatment type is incorrectly stated as 1.56. The correct Hazard ratio should be 4.78.</p><p>We apologize for this error.</p>","PeriodicalId":36909,"journal":{"name":"Journal of Experimental Orthopaedics","volume":"13 3","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13510621/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148833159","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Femoral derotational osteotomy reduces knee version significantly in contrast to tibial derotational osteotomy.","authors":"Anne Thielmann, Christoph Lutter, Annett Klinder, Jörg Harrer, Jörg Dickschas, Thomas Tischer, Johanna Lippuner, Felix Ferner","doi":"10.1002/jeo2.70832","DOIUrl":"10.1002/jeo2.70832","url":null,"abstract":"<p><strong>Purpose: </strong>The knee version has increasingly been recognised as a potential contributing risk factor to patellofemoral maltracking. However, it remains unclear whether the knee version can be influenced by surgical procedures such as derotational osteotomies. Therefore, the aim of this study was to elevate the effect of derotational osteotomies on knee version. The hypothesis of this study is that derotational osteotomies improve knee version in patients with abnormal knee version and that the magnitude of change of knee version correlates to the extent of the correction.</p><p><strong>Methods: </strong>The patient cohort consisted of 37 patients, 16 patients were treated with a tibial and 21 patients with a femoral derotational osteotomy. Standardised computer tomography (CT) scan was obtained pre and postoperative and the knee version was measured. The values were compared within the whole study population and divided into a tibial and a femoral group.</p><p><strong>Results: </strong>A significant decrease in knee version by 3.1° on average of the patient population was found between pre and postoperative values (<i>p</i> < 0.0001). In tibial osteotomies, the decrease of knee version was not statistically significant (0<i>p</i> = 0.1116), whereas in femoral osteotomies the decrease was statistically significant (<i>p</i> < 0.0001). No strong correlation was found between the degree of torsional correction and the degree of change in knee version.</p><p><strong>Conclusion: </strong>This study shows that pathological increased knee version can be reduced by derotational osteotomy, although only the femoral osteotomy was significantly effective in contrast to tibial osteotomy. Furthermore, there was no correlation between the degree of derotation and the magnitude of change in knee version.</p><p><strong>Level of evidence: </strong>Level IV.</p>","PeriodicalId":36909,"journal":{"name":"Journal of Experimental Orthopaedics","volume":"13 3","pages":"e70832"},"PeriodicalIF":3.2,"publicationDate":"2026-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13505595/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148819727","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Increased sagittal patellar height and reduced trochlear engagement on MRI are associated with recurrent patellar instability in skeletally immature knees: A comparative study","authors":"Francesco Puglia,&nbsp;Paolo Ferrua,&nbsp;David H. Dejour,&nbsp;Marco Nicoletti,&nbsp;Alessio Volpe,&nbsp;Riccardo Compagnoni,&nbsp;Antonio Memeo,&nbsp;Pietro Simone Randelli","doi":"10.1002/jeo2.70896","DOIUrl":"https://doi.org/10.1002/jeo2.70896","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>To apply the magnetic resonance imaging (MRI)-based concept of functional patella alta to skeletally immature patients and compare sagittal patellar height and trochlear engagement between paediatric knees with objective patellar instability (OPI) and controls without patellofemoral disorders.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>This retrospective study included 85 skeletally immature knees (42 OPI and 43 controls) from 83 patients undergoing MRI between 2021 and 2025. OPI required at least two lateral patellar dislocations. Measurements included patellar height index (PHI), sagittal patellar cartilage length (SPCL), patello-tibial distance (PTD), patellar tendon length (PTL), sagittal trochlear cartilage length (STCL) and sagittal patellofemoral engagement (SPE). Three blinded observers measured every knee; their mean was analysed. Functional patella alta was defined using control-derived interquartile-range thresholds. Interobserver reliability used two-way random-effects, absolute-agreement intraclass correlation coefficients (ICCs). Group comparisons and logistic regression were performed.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>OPI knees had significantly higher PHI (1.178 ± 0.171 vs. 1.083 ± 0.132; <i>p</i> = 0.005) and lower SPE (0.354 ± 0.207 vs. 0.484 ± 0.200; <i>p</i> = 0.004), with greater SPCL, PTD and PTL and shorter STCL (all <i>p</i> &lt; 0.05). Groups were unmatched for age, with older OPI patients (<i>p</i> &lt; 0.001). Functional patella alta occurred in 16/85 knees (18.8%): 14/42 OPI (33.3%) and 2/43 controls (4.7%) and was strongly associated with OPI (odds ratio [OR] 10.25; 95% confidence interval [CI] 2.16–48.66; <i>p</i> = 0.003). Reliability was excellent for SPE (ICC 0.95), PTL (0.97) and PTD (0.94), good for SPCL (0.80) and moderate for PHI (0.72).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>Paediatric recurrent patellar instability is characterised by increased patellar height and reduced sagittal trochlear engagement on MRI. Functional patella alta applies to skeletally immature knees, but instability occurs at lower sagittal engagement values than in adults. These cohort-specific exploratory thresholds require external validation before clinical use.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Level of Evidence</h3>\u0000 \u0000 <p>Level III, retrospective comparative study.</p>\u0000 </section>\u0000 </div>","PeriodicalId":36909,"journal":{"name":"Journal of Experimental Orthopaedics","volume":"13 3","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jeo2.70896","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148784940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biomechanical differences between females and males with patellofemoral pain: A systematic review and meta-analysis.","authors":"Lucas Pallone, Carolline P Nunes, Felipe F Gonzalez, Talissa O Generoso, Rodrigo Saad-Berreta, Kaitlyn M Joyce, Eliane C Guadagnin, Jorge Chahla, Jonathan A Gustafson, Leonardo Metsavaht, Gustavo Leporace","doi":"10.1002/jeo2.70880","DOIUrl":"10.1002/jeo2.70880","url":null,"abstract":"<p><strong>Purpose: </strong>Patellofemoral pain (PFP) is more prevalent in females and altered lower limb biomechanics have been implicated in its development and persistence. However, it remains unclear whether movement patterns differ between men and women with PFP during functional activities. Many biomechanical studies rely on mixed-sex cohorts, potentially obscuring sex-specific movement patterns. Therefore, this study aimed to systematically review biomechanical differences between females and males with PFP during functional tasks.</p><p><strong>Methods: </strong>PubMed/MEDLINE, Embase, Scopus, CINAHL, Cochrane CENTRAL, Cochrane Database of Systematic Reviews and Google Scholar were searched from inception to 10 September 2025. Studies comparing in vivo biomechanical characteristics of females and males with PFP during functional tasks were included, whereas studies using mixed-sex cohorts without sex-stratified analysis or focusing exclusively on a single sex were excluded. Extracted data comprised participant demographics, methodological characteristics and kinetic and kinematic outcomes. Methodological quality was assessed using a modified Downs and Black checklist. Random-effects meta-analyses were performed using standardized mean differences.</p><p><strong>Results: </strong>Five cross-sectional studies including 170 individuals with PFP (84 females and 86 males) were analysed. Tasks evaluated included single-leg squat, step-down, mini-squat and single-leg jumping activities. Meta-analysis of single-leg squat data showed greater peak hip adduction in females compared with males (mean difference 4.93°, 95% confidence interval [CI] 2.60-7.25; <i>I</i> ² = 0%). Females also demonstrated greater peak knee abduction (mean difference 5.74°, 95% CI 2.31-9.16; <i>I</i> ² = 66%). No significant differences were observed for contralateral pelvic drop. Qualitative synthesis indicated greater frontal-plane kinematics in females, whereas males demonstrated greater hip, knee and ankle extension moments during jumping tasks. Several findings were based on single studies.</p><p><strong>Conclusions: </strong>Only a limited number of studies evaluated sex-specific biomechanics in individuals with PFP. Despite the small number of studies, consistent differences between females and males were observed, suggesting that sex influences movement strategies and should be considered in biomechanical assessment and rehabilitation.</p><p><strong>Level of evidence: </strong>Level IV.</p>","PeriodicalId":36909,"journal":{"name":"Journal of Experimental Orthopaedics","volume":"13 3","pages":"e70880"},"PeriodicalIF":3.2,"publicationDate":"2026-08-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13495770/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148799100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Addition of a second double-row reduces fragment micromotion and increases fixation strength in suture fixation of a bony Bankart injury: A biomechanical study","authors":"Maximilian Hinz,&nbsp;Ayham Jaber,&nbsp;Justin F. M. Hollenbeck,&nbsp;Rio R. Castro,&nbsp;Wyatt H. Buchalter,&nbsp;Matthew T. Provencher,&nbsp;Peter J. Millett","doi":"10.1002/jeo2.70881","DOIUrl":"https://doi.org/10.1002/jeo2.70881","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>The purpose of the present study was to evaluate micromotion and failure load when the bony Bankart bridge (BBB) is performed with one versus two double-rows. It was hypothesized that the addition of a second double-row would reduce fragment micromotion and increase ultimate failure load.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Seven pairs of fresh-frozen cadaveric shoulders (age: 48 years [22–65 years], sex: 57.1% male) with bony Bankart lesions, with a defect width of 25% of the glenoid diameter, were tested in the present study. In a paired design, one shoulder underwent the BBB with one double-row, and the contralateral shoulder underwent the BBB with two double-rows. Micromotion of the bony Bankart fragment was tested by cyclic non-physiological point loading (5–20 N at 1 Hz for 50 cycles) using a dynamic tensile machine. Optical markers and a three-dimensional digitizer established fragment and glenoid coordinate systems, enabling precise tracking of translational and rotational displacements of the fragment. This was followed by failure testing, where the fragment was loaded to failure at 0.5 mm/s. Failure load and stiffness were recorded.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Under inferior point loading, the repair with one double-row demonstrated significantly greater rotation about the <i>x</i>-axis (5.20° [3.01°–5.29°] vs. 1.64° [0.94°–2.40°], <i>p</i> = 0.016, <i>q</i> = 0.047) and translation along the <i>z</i>-axis (2.78 mm [1.81–4.20 mm] vs. 1.06 mm [0.51–1.51 mm], <i>p</i> = 0.016, <i>q</i> = 0.047) compared with the repair with two double-rows. Under superior point loading, no significant differences were observed for the rotational or translational outcomes. The repair with one double-row demonstrated a significantly lower failure load than the repair with two double-rows (388 N [243–463 N] vs. 602 N [539–641 N], <i>p</i> = 0.016, <i>q</i> = 0.031). No significant differences in stiffness were found between groups.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Fixation with two double-rows resulted in a significantly less fragment micromotion and a significantly greater failure strength compared with the BBB using one double-row.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Level of Evidence</h3>\u0000 \u0000 <p>N/A.</p>\u0000 </section>\u0000 </div>","PeriodicalId":36909,"journal":{"name":"Journal of Experimental Orthopaedics","volume":"13 3","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jeo2.70881","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148783766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Posterior tibial slope is associated with ACL status rather than demographic factors: A cohort of 1406 patients","authors":"Julien Druel,&nbsp;Romir Patel,&nbsp;Christophe Jacquet,&nbsp;Lyes Chaal,&nbsp;Antoine Piercecchi,&nbsp;Matthieu Ollivier","doi":"10.1002/jeo2.70890","DOIUrl":"https://doi.org/10.1002/jeo2.70890","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>To determine whether posterior tibial slope (PTS), measured on lateral radiographs using the proximal anatomical tibial axis defined by two circles, is independently associated with anterior cruciate ligament (ACL) injury status or influenced by age, sex and body mass index (BMI).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>A retrospective single-centre cohort study included all 1406 consecutive eligible patients operated between January 2010 and September 2024: 857 ACL-intact controls undergoing medial patellofemoral ligament reconstruction, 498 patients with primary ACL rupture and 51 patients with ACL re-rupture. PTS was measured on standardized lateral radiographs using the proximal anatomical tibial axis defined by two circles. Multivariable linear regression evaluated the independent associations of ACL status, age, sex and BMI with PTS. Receiver operating characteristic (ROC) analyses assessed discrimination of ACL injury.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Mean PTS was 7.3 ± 3.1° in controls, 9.9 ± 3.1° in patients with primary ACL rupture and 10.9 ± 3.5° in patients with ACL re-rupture (<i>p</i> &lt; 0.001). Intraobserver and interobserver reliability were good to excellent (intraclass correlation coefficient [ICC] = 0.88) and moderate to good (ICC = 0.81). Multivariable analysis demonstrated that ACL injury status was the dominant independent determinant of PTS. Compared with controls, primary ACL rupture and ACL re-rupture were associated with 2.52° and 3.63° greater PTS, respectively (both <i>p</i> &lt; 0.001). Age showed a minimal inverse association (−0.019° per year; 95% confidence interval [CI], −0.036° to −0.003°; <i>p</i> = 0.024), whereas sex and BMI were not independently associated with PTS. ROC analysis identified a Youden-derived value of 10°, with an area under the curve of 0.731 (95% CI, 0.705–0.758) for primary ACL rupture and 0.791 (95% CI, 0.741–0.841) for ACL re-rupture.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>PTS was independently associated with ACL injury and ACL re-rupture, whereas age, sex and BMI had no clinically meaningful independent influence. PTS should be interpreted as one component of a multifactorial anatomical risk profile rather than as a standalone screening test.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Level of Evidence</h3>\u0000 \u0000 <p>Level III, retrospective comparative cohort study.</p>\u0000 </section>\u0000 </div>","PeriodicalId":36909,"journal":{"name":"Journal of Experimental Orthopaedics","volume":"13 3","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jeo2.70890","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148783779","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"External validation of the BABY-Knee Algorithm for treatment decision-making in skeletally immature patients with anterior cruciate ligament injuries: A Dutch cohort study","authors":"Annika Babette Ito,&nbsp;Rob Paulus Augustinus Janssen,&nbsp;Stijn Thomas Henricus Croes,&nbsp;Robin Nicolaas Julian Voskuilen,&nbsp;Alberto Grassi,&nbsp;Maria Christine van der Steen,&nbsp;Martijn Dietvorst","doi":"10.1002/jeo2.70891","DOIUrl":"10.1002/jeo2.70891","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>The aim of this study was to investigate the external validity of the Best anterior cruciate ligament (ACL)-treatment Based on the Years of the Knee (BABY-Knee) Algorithm, developed based on an Italian population and to assess its applicability to a Dutch patient population treated in accordance with the 2018 International Olympic Committee (IOC) consensus statement.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>A total of 109 skeletally immature patients with ACL injuries were included from the Dutch contribution to the European Society of Sport Traumatology, Knee Surgery and Arthroscopy (ESSKA) Paediatric Monitoring Initiative (PAMI). The BABY-Knee Algorithm was retrospectively applied to all patients, and corresponding scores were calculated. The predictive performance of the BABY-Knee Algorithm was assessed using the validation approach of the original validation study and an additional failure criterion based on hard clinical endpoints. Results were compared with the previously reported results.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Of the 109 patients included, 78 (71.6%) were treated non-operatively, while the remaining 31 (28.4%) underwent operative treatment. However, according to the algorithm, 34 patients (31.2%) had a score of &lt;3, indicating non-operative treatment, whereas 75 patients (68.8%) had a score of ≥3, indicating operative treatment. A statistically significant difference was observed between the algorithm's prediction and the performed treatment (<i>p</i> = 0.003). The original internal validation study reported a positive predictive value (PPV) of 91.7% and a negative predictive value (NPV) of 87.5%. In contrast, application of the BABY-Knee Algorithm to the present study population resulted in a PPV of 51.1% or 31.9% and an NPV of 64.5% or 67.7%, depending on the applied definition of failure.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>The external validation of the BABY-Knee Algorithm showed inferior predictive performance compared with the original internal validation study in an Italian population. These findings suggest that the BABY-Knee Algorithm is not directly applicable to other populations of skeletally immature patients with ACL injuries.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Level of Evidence</h3>\u0000 \u0000 <p>Level III.</p>\u0000 </section>\u0000 </div>","PeriodicalId":36909,"journal":{"name":"Journal of Experimental Orthopaedics","volume":"13 3","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13484896/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148798984","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Clustering analysis of hamstring injuries-A pilot study to determine phenogroups based on injury characteristics and recovery duration.","authors":"Bálint Zsidai, György Gulácsi, Tibor Rudisch, Bence Márk Kovács, Pete Friar, Richard Nagy, Robert de Jonge, Eric Hamrin Senorski, Kristian Samuelsson, Gergely Pánics","doi":"10.1002/jeo2.70885","DOIUrl":"https://doi.org/10.1002/jeo2.70885","url":null,"abstract":"<p><strong>Purpose: </strong>The objective of this pilot study was to determine clinically relevant phenogroups of professional football players with hamstring injuries using unsupervised cluster analysis based on demographic and injury-related characteristics, and to assess return to play (RTP) duration with respect to the characteristics of these phenogroups.</p><p><strong>Methods: </strong>This retrospective cohort study analysed 57 professional football players from Ferencvárosi Torna Club with magnetic resonance imaging (MRI)-confirmed acute hamstring injuries reported between 2018 and 2024. Three clustering approaches were implemented and compared: k-means clustering, hierarchical clustering using Ward's linkage method, and mixed-type clustering using Gower distance with partitioning around medoids (PAMs). The optimal number of clusters was determined using silhouette analysis. Between-cluster differences in RTP duration and injury characteristics were assessed using Kruskal-Wallis tests for continuous variables and chi-square tests for categorical variables, with post-hoc Bonferroni correction.</p><p><strong>Results: </strong>Mixed-type clustering identified seven phenogroups based on British Athletics Muscle Injury Classification (BAMIC) grade, lesion length, anatomical tear site, affected muscle and injury extensiveness. The average silhouette width was 0.290, indicating weak to moderate cluster separation. Clusters 1, 3, 4, 5 and 6 were characterised by low- to moderate-grade injury parameters and median RTP durations ranging from 9 to 27 days. Clusters 2 and 7 displayed high-grade injury characteristics with considerably prolonged RTP (medians of 46.5 and 94.5 days, respectively). Significant between-cluster differences were observed for days to RTP, lesion length, BAMIC grade, injury severity and anatomical tear site (<i>p</i> < 0.05).</p><p><strong>Conclusions: </strong>Unsupervised machine learning may help identify clinically relevant hamstring injury phenogroups based on MRI-derived tear characteristics, which may facilitate prognosis and inform decision-making regarding expected RTP duration in professional football players.</p><p><strong>Level of evidence: </strong>Level IV, retrospective cohort study.</p>","PeriodicalId":36909,"journal":{"name":"Journal of Experimental Orthopaedics","volume":"13 3","pages":"e70885"},"PeriodicalIF":3.2,"publicationDate":"2026-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13479470/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148799120","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}