Journal of Experimental Orthopaedics最新文献

{"title":"Physical activity after unicompartmental knee arthroplasty: Long-term participation, activity volume and patient-reported limitations","authors":"Waldo Gonzalez,&nbsp;Jorge Isla,&nbsp;Diego Barba,&nbsp;Daniela Erskine,&nbsp;Daniela Landea,&nbsp;Camila Tapia,&nbsp;David Figueroa","doi":"10.1002/jeo2.70929","DOIUrl":"10.1002/jeo2.70929","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>To characterize long-term patient-reported sports and physical activity after unicompartmental knee arthroplasty (UKA), including participation, weekly volume, perceived exertion, time to resumption, limitations, satisfaction and sex-based differences.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>This retrospective single-institution study included 150 patients who underwent primary UKA between 2014 and 2022. An 11-item electronic questionnaire administered in 2025 assessed activity at 5 years before UKA, 1 year before UKA, 1 year after UKA and at current follow-up. Current participation was the primary outcome. Historical responses were treated as retrospectively recalled estimates. Mean follow-up was 6.8 ± 2.4 years.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Of 190 contactable patients, 150 responded (78.9%). Mean age was 65.1 ± 10.9 years. Participation was recalled by 33.3% at 5 years before UKA, 8.0% at 1 year before UKA and 25.3% at 1 year after UKA; 33.3% reported current participation. Among current participants, 74.0% reported &gt;3 h/week and 48.0% reported moderate-or-higher exertion. Overall, 49.3% resumed activity within 12 months, 42.0% perceived improvement and mean satisfaction was 3.84 ± 1.30. Activity-related limitations and long-term restrictions were reported by 75.3% and 30.0%, respectively. Most outcomes were similar between women and men; the fully adjusted association between male sex and improved intensity was not significant (adjusted odds ratio 2.08, 95% confidence interval 0.90–4.80).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>At long-term follow-up after UKA, one-third of patients reported current sports or physical activity participation, and most current participants reported &gt;3 h/week. However, only half resumed activity within 12 months, and residual limitations were common. Historical group-level proportions should not be interpreted as individual return to activity or longitudinal recovery.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Level of Evidence</h3>\u0000 \u0000 <p>Level IV.</p>\u0000 </section>\u0000 </div>","PeriodicalId":36909,"journal":{"name":"Journal of Experimental Orthopaedics","volume":"13 4","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13633556/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149115942","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":"No clear association between time to return-to-play and first additional injury in European professional football players after ACL injury: A media-based study","authors":"Andrea Marchetti,&nbsp;Michelangelo Scordo,&nbsp;Lorenzo Scarpi,&nbsp;Massimiliano Colotti,&nbsp;Belinda Trobec,&nbsp;Raffaele Sabot,&nbsp;Manuela Deodato,&nbsp;Gianluca Canton,&nbsp;Luigi Murena,&nbsp;Ramana Piussi","doi":"10.1002/jeo2.70934","DOIUrl":"10.1002/jeo2.70934","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>The primary aim of this media-based study was to investigate whether time from anterior cruciate ligament (ACL) injury to return to play (RTP) was associated with the hazard of a first additional injury over calendar time among male professional football players in the five major European leagues. Secondary aims were to examine associations with a first additional injury within 365 days after RTP and with the number of official competitive matches missed because of the first additional injury.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Male professional football players who sustained an ACL injury, underwent ACL reconstruction and returned to official competition were identified from publicly available data. RTP was defined as the first official competitive match after ACL injury. Cox proportional hazards regression assessed associations over the full follow-up and within 365 days, adjusted for age and player position. Sensitivity analysis examined predefined RTP categories; negative binomial regression assessed the association between time to RTP and the number of official competitive matches missed because of the first additional injury.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Among 278 players, mean time to RTP was 242.3 ± 99.5 days and 201 (72.3%) sustained a first additional injury. No clear evidence of an association was observed between time to RTP and the hazard of a first additional injury over the full follow-up or within 365 days. Similarly, no clear evidence of an association was observed in the categorical sensitivity analysis or between time to RTP and the number of matches missed because of the first additional injury.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>No clear evidence of an association was observed between time from ACL injury to RTP and the hazard of a first additional injury either over the full follow-up period or within 365 days after RTP. Similarly, no clear evidence of an association was observed between time to RTP and the number of official competitive matches missed because of the first additional injury.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Level of Evidence</h3>\u0000 \u0000 <p>Level IV.</p>\u0000 </section>\u0000 </div>","PeriodicalId":36909,"journal":{"name":"Journal of Experimental Orthopaedics","volume":"13 4","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13633551/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149115982","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":"Surgical approach and insert constraint are associated with small differences in patellar tilt after robotic-assisted total knee arthroplasty: A retrospective comparative radiographic study.","authors":"Clément Favroul, Mehdi Drissi Kaitouni, Elvire Servien, Cécile Batailler, Sébastien Lustig","doi":"10.1002/jeo2.70933","DOIUrl":"https://doi.org/10.1002/jeo2.70933","url":null,"abstract":"<p><strong>Purpose: </strong>Patellofemoral alignment remains important after total knee arthroplasty (TKA). Robotic-assisted functional positioning may reduce the impact of approach- and implant-related factors on the patellofemoral joint. This study evaluated the association between surgical approach and insert constraint with postoperative static patellar alignment following robotic-assisted TKA.</p><p><strong>Methods: </strong>This retrospective comparative radiographic study included 320 primary nonresurfaced robotic-assisted TKA performed with the MAKO system between March 2021 and December 2024. Patients were divided into four groups: mini-subvastus condylar-stabilised (MSV-CS, <i>n</i> = 134), mini-subvastus posterior-stabilised (MSV-PS, <i>n</i> = 63), medial parapatellar condylar-stabilised (MPP-CS, <i>n</i> = 75) and medial parapatellar posterior-stabilised (MPP-PS, <i>n</i> = 48). Standardised Merchant axial radiographs at 30° and lateral radiographs were obtained at 2 months and 1 year. Patellar tilt was the primary outcome. Secondary outcomes were qualitative patellar centreing, patellar thickness and the modified Blackburne-Peel index. Two-way factorial analysis assessed surgical approach, insert constraint and their interaction.</p><p><strong>Results: </strong>Baseline characteristics and final intraoperative robotic alignment parameters were comparable across groups. MSV and CS implants were associated with statistically greater patellar tilt than MPP and PS implants, respectively, but the absolute differences were small, approximately 1°. No significant interaction was observed between surgical approach and insert constraint. Patellar height did not differ between groups.</p><p><strong>Conclusion: </strong>Robotic-assisted functional positioning provided consistent static patellofemoral alignment regardless of surgical approach or insert constraint. Although statistically significant differences in patellar tilt were detected, their approximately 1° magnitude suggests a negligible radiographic effect. Their clinical significance remains unknown because clinical outcomes and dynamic patellar tracking were not assessed.</p><p><strong>Level of evidence: </strong>Level IV.</p>","PeriodicalId":36909,"journal":{"name":"Journal of Experimental Orthopaedics","volume":"13 4","pages":"e70933"},"PeriodicalIF":3.2,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13633553/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149115945","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":"Significant variability in limb symmetry across four different knee flexion strength tests after anterior cruciate ligament reconstruction.","authors":"Johan Högberg, Mathias Wernbom, Axel Sundberg, Emilia Hermansson, Ted Larsson, Filip Adell, Kristian Samuelsson, Eric Hamrin Senorski","doi":"10.1002/jeo2.70932","DOIUrl":"https://doi.org/10.1002/jeo2.70932","url":null,"abstract":"<p><strong>Purpose: </strong>To investigate knee flexion strength symmetry across four different strength tests in patients who underwent anterior cruciate ligament (ACL) reconstruction (ACLR) using hamstring tendon (HT) autograft.</p><p><strong>Methods: </strong>Data were collected between June 2024 and August 2025. Patients who underwent ACLR with HT autograft and performed (a) seated isokinetic concentric knee flexion (Biodex), (b) Nordic hamstring exercise (NordBord), (c) prone isometric 90° knee flexion with dorsiflexion (ISO90 DF) and (d) plantar flexion (ISO90 PF) ≥ 4 months after ACLR were included. The primary analysis was the cross-sectional pairwise comparison of limb symmetry index (LSI) using a paired-samples <i>t</i> test. The secondary analysis compared the proportion of patients achieving an LSI ≥ 90% in each testing modality using McNemar's test. Comparisons with a control group consisting of patients with patellar tendon and quadriceps tendon autografts were performed using an independent-samples <i>t</i> test and Fisher's exact test, respectively. Statistical significance was set at <i>p</i> < 0.05.</p><p><strong>Results: </strong>A total of 101 patients were included, including a control group (<i>n</i> = 33). Patients with HT autograft had a mean age of 25 ± 8 years, with the most common follow-up time being 12 months. Knee flexion strength in the Biodex displayed the LSI closest to symmetry (98.4%). The mean difference was 43.9% ± 16.7% (95% confidence interval [CI] [39.9; 47.8%], <i>p</i> < 0.001, <i>d</i> = 2.62 95% CI [2.1; 3.1]) compared to the LSI of the prone ISO90 PF. Fifty-seven (80%) patients passed the ≥90% cut-off in LSI for the Biodex test, while only 2 (3%) patients passed the prone ISO90 PF. The HT autograft group demonstrated lower LSI with the NordBord, ISO90 DF and ISO90 PF (<i>Δ</i> = -12.2 to -37.4%, <i>p</i> = 0.001 to <0.001) compared with the control group.</p><p><strong>Conclusions: </strong>Knee flexion strength LSI varied substantially across the four test modalities in patients with HT autograft, highlighting the need to consider the hip, knee and ankle positions when evaluating knee flexion strength recovery after ACLR in patients with HT autograft.</p><p><strong>Level of evidence: </strong>Level II, prospective comparative study.</p>","PeriodicalId":36909,"journal":{"name":"Journal of Experimental Orthopaedics","volume":"13 4","pages":"e70932"},"PeriodicalIF":3.2,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13633671/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149115955","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":"Joint line obliquity change was associated with femoral and tibial resection patterns and smaller final flexion imbalance after robot-assisted total knee arthroplasty","authors":"Yugo Morita,&nbsp;Jonggu Shin,&nbsp;Mohammed El-Hassan,&nbsp;Ittai Shichman,&nbsp;William J. Long,&nbsp;Peter K. Sculco","doi":"10.1002/jeo2.70936","DOIUrl":"10.1002/jeo2.70936","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Purpose</h3>\u0000 \u0000 <p>Associations between preoperative-to-post-operative changes in arithmetic hip–knee–ankle angle (aHKA) and joint line obliquity (JLO) and final balance after robot-assisted total knee arthroplasty (TKA) were evaluated. Relationships with resection redistribution and tibial-varus reduction were also examined.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>A retrospective single-surgeon series of 402 primary robot-assisted TKAs was analysed. Preoperative and post-operative aHKA, JLO and coronal plane alignment of the knee (CPAK) type were determined from full-length radiographs. Final extension and flexion imbalance and laxity ranges after trial implantation were the primary outcomes. Signed and absolute changes were assessed in multivariable models; resection redistribution and a varus-only tibial-boundary subgroup were examined in supportive analyses.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>A change in CPAK type was observed in 300 knees (74.6%), including a JLO-zone change in 221 (55.0%). Greater ΔJLO was associated with smaller final flexion imbalance (β = −0.060; p &lt; 0.001) and a narrower final extension laxity range (<i>β</i> = −0.055; <i>p</i> = 0.002). Corresponding associations were found for |ΔJLO| (<i>β</i> = −0.046; <i>p</i> = 0.018 and <i>β</i> = −0.070; <i>p</i> = 0.004). Neither signed nor absolute aHKA change was associated with final extension or flexion imbalance. In varus knees, tibial-varus reduction was associated with greater JLO and aHKA changes, coronal femoral adjustment and smaller final flexion imbalance. Neither |ΔaHKA| nor |ΔJLO| was associated with improvement in the Knee injury and Osteoarthritis Outcome Score for Joint Replacement.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Greater JLO change was associated with smaller final flexion imbalance and a narrower extension laxity range rather than impaired balance. In varus knees, JLO change accompanied tibial-varus reduction and coordinated femoral adjustment. JLO change may therefore reflect specific aspects of the final balancing state rather than an unintended deviation from the native phenotype.</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 4","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13633672/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149115926","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":"Guideline-augmented prompting improves comparative preference and response consistency of large language model outputs for orthopaedic anaesthesia questions: A controlled prompting study","authors":"Anita Széll,&nbsp;Yinan Yu,&nbsp;Jacob F. Oeding,&nbsp;Felix C. Oettl,&nbsp;Adam Piasecki,&nbsp;Keti Dalla,&nbsp;Tobias Siöland,&nbsp;Mathias Hård af Segerstad,&nbsp;Fredrik Olsen,&nbsp;Peter Larsson,&nbsp;Stefano Zaffagnini,&nbsp;Kristian Samuelsson,&nbsp;Fredrik Hessulf","doi":"10.1002/jeo2.70922","DOIUrl":"10.1002/jeo2.70922","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;Large language models (LLMs) are increasingly used in clinical contexts; however, performance in complex perioperative decision-making remains uncertain. Orthopaedic anaesthesia presents a demanding test case due to comorbidity burden and guideline-dependent management. Whether successive LLM generations and guideline-augmented prompting improve clinical alignment, comparative performance and response consistency was evaluated in this study.&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;In this controlled prompting study, 34 orthopaedic anaesthesia questions spanning seven clinical subdomains were independently answered by three LLMs (GPT-3.5-turbo, GPT-4o and GPT-5.2) and three expert anesthesiologists. GPT-4o and GPT-5.2 each generated responses with and without access to relevant clinical practice guidelines. All responses were anonymized and evaluated in blinded pairwise comparisons by an independent guideline-informed LLM-as-a-judge (GPT-5.2) using the same guideline material as the reference standard. The judge recorded preference, response consistency and confidence. Intra-model consistency was assessed from repeated independent generations of each question.&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;All LLMs were preferred over human experts in pairwise comparisons without guideline augmentation, with win rates of 67.6% (GPT-3.5-turbo), 79.4% (GPT-4o) and 95.1% (GPT-5.2). Performance was improved by guideline augmentation, most notably for GPT-4o (91.2%, +11.8 percentage points), while GPT-5.2 approached ceiling performance (97.1%). Response consistency varied between models. GPT-4o showed the highest baseline consistency (80.4%), whereas GPT-5.2 demonstrated no fully contradictory outputs but showed greater partial variability. Guideline augmentation numerically improved GPT-5.2 consistency (66.7% to 80.4%) and reduced inter-model differences. Directed qualitative analysis suggested that reviewer preference for later GPT generations was associated with greater completeness, explicit clinical reasoning and guideline-oriented responses.&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Conclusion&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;Successive LLM generations demonstrated progressively improved performance in orthopaedic anaesthesia reasoning. Guideline-augmented prompting enhanced response quality, particularly for intermediate models. Guideline-informed LLM-as-a-judge evaluation appears promising for comparative assessment but requires further validation.&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 ","PeriodicalId":36909,"journal":{"name":"Journal of Experimental Orthopaedics","volume":"13 4","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13633554/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149115965","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":"Excellent survivorship and functional outcomes following lateral unicompartmental knee arthroplasty in patients aged 55 years or younger","authors":"Solongo Abdulai,&nbsp;Conradin Schweizer,&nbsp;Valentin Rühle,&nbsp;Tatjana Krug,&nbsp;Raffaela Morgenbesser,&nbsp;Joachim Herre,&nbsp;Peter R. Aldinger,&nbsp;Christian Merle,&nbsp;Wenzel Waldstein","doi":"10.1002/jeo2.70935","DOIUrl":"10.1002/jeo2.70935","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;Fixed-bearing lateral unicompartmental knee arthroplasty (UKA) is a bone- and ligament-preserving treatment option for isolated lateral-compartment osteoarthritis (OA), but evidence in younger patients remains limited. The primary purpose of this study was to assess lateral component revision-free survival and reoperation-free survival following primary fixed-bearing lateral UKA in patients aged 55 years or younger. Secondary objectives were to evaluate functional and radiological outcomes.&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;This retrospective case series was derived from a prospectively maintained institutional database. A consecutive series of 84 primary fixed-bearing lateral UKAs in 80 patients aged ≤55 years, performed between January 2016 and December 2021 with a minimum follow-up of 2 years was identified (mean follow-up, 5.3 ± 1.9 years [range, 2.2–8.6 years]; mean age, 51 years [range, 37–55 years]). Kaplan-Meier analysis estimated 5-year survival for lateral component revision or reoperation. Lateral component revision was defined as the removal or exchange of any fixed implant component (femoral or tibial). Reoperation was defined as any subsequent surgical procedure on the operated knee. Functional outcomes were evaluated using the Oxford Knee Score (OKS) and University of California, Los Angeles Activity Score. Radiographic assessment included measurement of the hip-knee-ankle angle (HKAA).&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;Lateral component revision-free survival was 100%, while cumulative reoperation-free survivorship was 92.5% (95% CI: 86.8–98.2) at 5 years. Seven reoperations were observed: 4 additional medial UKAs, 2 arthroscopic procedures and 1 successful debridement, antibiotics and implant retention (DAIR). Mean HKAA changed from 4.8° ± 4.7° valgus preoperatively to 2.0° ± 2.8° valgus postoperatively. Postoperative HKAA demonstrated higher residual valgus in knees without medial-compartment OA progression or osteonecrosis (ON) compared to four knees with medial-compartment OA or ON (2.2° valgus vs. 1.5° varus, &lt;i&gt;p&lt;/i&gt; = 0.012). The mean postoperative OKS was 43.8 ± 5.7 and the UCLA Activity Score was 6.5 ± 1.2.&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;Fixed-bearing lateral UKA in younger patients was associated with 100% lateral component revision-free survival and high functional scores at a mean follow-up of 5 years. No implant-related failures, such as aseptic loosening, were observed in this active cohort, although seven knees underwent reoperation, inclu","PeriodicalId":36909,"journal":{"name":"Journal of Experimental Orthopaedics","volume":"13 4","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13633555/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149115977","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":"Artificial intelligence in orthopaedics should be built with surgeons, not just for them!","authors":"Felix C. Oettl,&nbsp;Balint Zsidai,&nbsp;Jacob Oeding,&nbsp;Ting Cong,&nbsp;Elmar Herbst,&nbsp;Gergely Pánics,&nbsp;Philipp W. Winkler,&nbsp;Volker Musahl,&nbsp;Eric Hamrin Senorski,&nbsp;Romain Seil,&nbsp;Christophe Ley,&nbsp;Yinan Yu,&nbsp;Thomas Tischer,&nbsp;Stefano Zaffagnini,&nbsp;Umile Giuseppe Longo,&nbsp;Michael T. Hirschmann,&nbsp;Michael Hantes,&nbsp;Kristian Samuelsson,&nbsp;ESSKA AI Committee","doi":"10.1002/jeo2.70920","DOIUrl":"https://doi.org/10.1002/jeo2.70920","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 <p>Surgical artificial intelligence (AI) is typically validated on one patient population and then deployed unchanged into another, without surgeon input into its design. AI in orthopaedics should be built with surgeons, not simply for them: Surgeons should hold shared authority over the clinical question, data curation, validation, implementation, monitoring and retirement of any tool they use. Specialty-tuned models outperform general-purpose systems on some tasks, but the margin is modest and likely to narrow as generalist models improve. The more durable distinction is who controls the update loop—who can retrain a model on local outcomes, audit its failures and withdraw it when it drifts. Trial evidence shows that a clinician kept in that loop by design, not as an afterthought, outperforms working alone. What determines whether orthopaedic AI fulfils its promise is not model architecture, but who stays accountable to the surgeon at the bedside when the model needs to change.</p>\u0000 </section>\u0000 </div>","PeriodicalId":36909,"journal":{"name":"Journal of Experimental Orthopaedics","volume":"13 4","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jeo2.70920","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149072592","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":"Comparable clinical outcomes and redislocation rates after isolated medial patellofemoral ligament reconstruction in patients with and without borderline anatomical risk factors for patellar instability","authors":"Alessio Maione,&nbsp;Simone Romano,&nbsp;Pierrenzo Pozzi,&nbsp;Matteo D. Parmigiani,&nbsp;Alessandra Menon,&nbsp;Paolo Ferrua,&nbsp;Filippo Calanna,&nbsp;Riccardo Compagnoni,&nbsp;Eva Usellini,&nbsp;Andrea Mambretti,&nbsp;Massimo Berruto,&nbsp;Pietro S. Randelli","doi":"10.1002/jeo2.70928","DOIUrl":"https://doi.org/10.1002/jeo2.70928","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;The purpose of this study was to compare mid- to long-term clinical outcomes and redislocation rates after isolated medial patellofemoral ligament (MPFL) reconstruction in patients with and without borderline anatomical risk factors. It was hypothesized that isolated MPFL reconstruction would provide comparable outcomes regardless of borderline anatomical abnormalities.&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;A retrospective comparative study was performed on 51 patients (55 knees) treated with isolated MPFL reconstruction for recurrent patellar instability between 2013 and 2023. Patients were divided into a standard group (Caton–Deschamps Index [CDI] &lt; 1.2, tibial tubercle–trochlear groove [TT–TG] &lt; 20 mm, absent or Type A trochlear dysplasia) and a borderline group (CDI 1.2–1.4, TT–TG 20–24 mm and/or Dejour Type B–D trochlear dysplasia without explosive J-sign or large trochlear spur). Clinical outcomes were assessed using Knee injury and Osteoarthritis Outcome Score (KOOS), Kujala, Tegner and Visual Analogue Scale (VAS) scores at a mean follow-up of 7.9 ± 3.9 years. Redislocations and complications were recorded.&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;Twenty-five knees were included in the standard group and 30 in the borderline group. Both groups showed significant improvement in all clinical scores from baseline to final follow-up (&lt;i&gt;p&lt;/i&gt; &lt; 0.001 for all). No significant differences were observed between groups at final follow-up in KOOS (88.9 ± 10.3 vs. 86.1 ± 9.5; &lt;i&gt;p&lt;/i&gt; = 0.159), Kujala (85.3 ± 18.8 vs. 86.9 ± 10.3; &lt;i&gt;p&lt;/i&gt; = 0.713), Tegner (4.0 ± 1.1 vs. 3.9 ± 1.3; &lt;i&gt;p&lt;/i&gt; = 0.765) or VAS scores (1.6 ± 1.1 vs. 2.1 ± 1.8; &lt;i&gt;p&lt;/i&gt; = 0.260). Redislocation rates were comparable between groups (4.0% vs. 6.7%; &lt;i&gt;p&lt;/i&gt; = 1.0). Within the borderline group, the cumulative burden of anatomical risk factors did not negatively affect outcomes.&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;Isolated MPFL reconstruction provides reliable and durable mid- to long-term outcomes in carefully selected patients with borderline anatomical risk factors, with clinical results and redislocation rates comparable to those observed in standard patients. These findings support a patient-specific surgical approach, suggesting that additional bony procedures should be reserved for clearly pathological anatomical abnormalities rather than routinely performed in borderline cases.&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Level of Evidence&lt;/h3&gt;","PeriodicalId":36909,"journal":{"name":"Journal of Experimental Orthopaedics","volume":"13 4","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jeo2.70928","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149072625","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":"Three injections of freeze-dried platelet factor concentrate provide greater clinical response than single injection in the treatment of knee osteoarthritis","authors":"Tadahiko Ohtsuru,&nbsp;Hiroto Hanai,&nbsp;Taro Akimori,&nbsp;Wataru Ando,&nbsp;Norimasa Nakamura,&nbsp;Stephen Lyman","doi":"10.1002/jeo2.70906","DOIUrl":"https://doi.org/10.1002/jeo2.70906","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;Single-injection freeze-dried platelet factor concentrate (PFC-FD) has been shown to be safe and effective in the treatment of early knee osteoarthritis (OA) with clear advantages over other PRP processing methods. No previous clinical investigations have examined multiple PFC-FD doses. The aim of this study was to assess the safety and effectiveness of one versus three PFC-FD injections in patients with knee OA.&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;Patients with Kellgren–Lawrence (KL) Grade I–IV knee OA were prospectively recruited via shared decision-making based on patient preference to receive either one (&lt;i&gt;n&lt;/i&gt; = 1054) or three (&lt;i&gt;n&lt;/i&gt; = 317) PFC-FD injections. Patients completed a pre-injection knee injury and OA outcomes survey (KOOS). Post-injection, patients completed the KOOS at 1, 3, 6 and 12 months. Adverse events were documented. Response to treatment was assessed using the Outcome Measures in Rheumatology (OMERACT)-Osteoarthritis Research Society International responder criteria. Multivariable modelling assessed treatment effectiveness, adjusting for patient differences.&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;The three-injection cohort demonstrated a small advantage in all KOOS subscales except quality of life (QOL) at 1 month (2.4–4.0 points, &lt;i&gt;p&lt;/i&gt; &lt; 0.0001–0.004), but this advantage disappeared by 3 months. When only early OA (KLI–II) was considered, the three-injection cohort demonstrated higher improvement at 1, 3 and/or 6 months for most KOOS subscales. No such differences were observed for advanced OA patients. Multivariable analysis demonstrates that three-injection patients were more likely to achieve responder status for KOOS-Pain and KOOS-activities of daily living (ADL) at 12 months (70.9% vs. 60.9%, &lt;i&gt;p&lt;/i&gt; = 0.02 and 55.7% vs. 47.3%, &lt;i&gt;p&lt;/i&gt; = 0.009, respectively). Overall patient-level adverse events were higher in the three-injection group (21.3% vs. 6.9%; &lt;i&gt;p&lt;/i&gt; &lt; 0.001), though adverse events per injection did not differ between groups (one-injection 6.9%, three-injection 8.6%; &lt;i&gt;p&lt;/i&gt; = 0.19).&lt;/p&gt;\u0000 &lt;/section&gt;\u0000 \u0000 &lt;section&gt;\u0000 \u0000 &lt;h3&gt; Conclusion&lt;/h3&gt;\u0000 \u0000 &lt;p&gt;Based on non-randomized allocation, a three-injection PFC-FD treatment protocol demonstrates a higher likelihood of clinical response compared to a one-injection protocol, particularly for relief of early knee OA symptoms, without evidence of an adverse immune response.&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 ","PeriodicalId":36909,"journal":{"name":"Journal of Experimental Orthopaedics","volume":"13 4","pages":""},"PeriodicalIF":3.2,"publicationDate":"2026-09-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/jeo2.70906","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149072626","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}