Journées Équations aux dérivées partielles

AbstractPurposeThe purpose of this research was to understand the trajectory of recovery following anterior cruciate ligament (ACL) reconstruction compared to nonoperative treatments.MethodsA systematic review and meta‐analysis approach was used to evaluate randomised controlled trials (RCTs). A comprehensive search was conducted on databases including Medline, Embase, Web of Science and The Cochrane Central Register of Controlled Trials up until 18 May 2023. The study focused on full‐text RCTs involving patients with partial or complete ACL tears. Included were studies focusing on patients undergoing ACL reconstruction or nonoperative care. The primary outcome was characterising the effects of treatments and tracking changes in International Knee Documentation Committee Subjective Knee Evaluation Form (IKDC) outcomes over time. The secondary outcome was characterising and tracking the changes of the knee injury and osteoarthritis outcome score subscales, ACL‐quality‐of‐life questionnaire, Lysholm, Tegner and CKRS scores.ResultsA total of 84 RCTs were included. The pooled standardised mean changes for the IKDC compared with baseline were: 2.0 (95% confidence interval [CI]: 0.3–3.6) at 3 months, 2.2 (95% CI: 0.9–3.6) at 6 months, 2.2 (95% CI: 0.8–3.6) at 12 months and 2.3 (95% CI: 1.3–3.4) at 24 months. Graphs illustrating IKDC scores over time further emphasise these findings, showing a sustained improvement over time to 12 months, with a plateauing of scores past this time point. Our secondary outcome patient‐reported outcome measures (PROMs) also showed a similar pattern with scores plateauing at the 12‐months mark.ConclusionOur findings suggest that the IKDC score and other PROMs are effective for tracking recovery up to 12 months. Other PROMs show pain and daily activities generally recover within 6 months, and quality of life improves up to 12 months, but PROMs show minimal improvement beyond this period. This inconsistency with a return sport period indicates that PROMs may lack the sensitivity required to assess this aspect of recovery accurately.Level of EvidenceLevel I.

AbstractPurposeSeveral posterior medial meniscal root (PMMR) repair techniques have been developed to restore the load‐bearing function of the meniscus and reduce extrusion. The medial meniscotibial ligament (MMTL) has been shown to play a significant role in meniscal stability. This study evaluates the stabilising function of the MMTL by directly influencing the force exerted on the PMMR during weight‐bearing and valgus motion of the knee. Our aim is to investigate whether loss of MMTL integrity is a determining factor in PMMR subluxation.MethodsUsing a 3D model of the knee with parameters from experimental studies, compressive and valgus loading scenarios were simulated using the finite element method to analyse the mechanical response of different knee structures. To investigate the correlation between the integrity of the MMTL and the force acting on the PMMR, different degrees and types of injuries to both structures were modelled for comparison with the healthy joint, providing insights into their importance in preventing or correcting extrusion.ResultsDuring compressive loading, tears in the MMTL and PMMR result in a 5.8% and 30.9% increase in meniscal extrusion, respectively, while a combined injury results in a 43.9% increase, indicating that the MMTL provides a secondary constraint against extrusion. Moreover, the importance of the MMTL in restraining extrusion becomes more pronounced as the PMMR weakens, as is typical in degenerative tears. Finally, during valgus motion, the MMTL prevents separation of the meniscus from the tibial plateau and reduces strain/stress on the PMMR.ConclusionThe integrity of the MMTL plays a crucial role in reducing meniscal extrusion and PMMR overload, particularly when the root is affected by degenerative tears. Therefore, surgical repair of the MMTL can improve meniscal function, potentially reducing the risk of osteoarthritis and should be considered as a better treatment strategy for PMMR tears.Level of EvidenceLevel III.

AbstractPurposeMultiple clinical factors may concur to determine the clinical trajectory leading towards total knee arthroplasty (TKA) in patients affected by knee osteoarthritis (OA). The aim of this study was to identify the main factors influencing progression to TKA in a large population of knee OA patients.MethodsA total of 7552 knees were selected from the Osteoarthritis Initiative (OAI) multicentre database. The data collected included demographic data, Kellgren–Lawrence (KL) grade, the presence of knee swelling, the frequency of swelling, visual analogue scale (VAS) for pain, Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC), Knee Injury and Osteoarthritis Outcome Score (KOOS) and the number of knees requiring TKA. The baseline data were collected as reported by the OAI database, and patients were followed up at 12, 24, 36, 48, 60, 72, 84 and 96 months, documenting whether they underwent TKA during this period.ResultsA multivariable analysis was performed to identify factors independently influencing progression to TKA. At 96 months, 7.1% of knees underwent TKA. The progression to TKA correlated with age (p < 0.001), KL grade (p < 0.001), swelling frequency (p < 0.001), knee swelling (p < 0.001), VAS (p = 0.003) and KOOS (p < 0.001). Knees with KL Grades 3 and 4 had the same risk of undergoing this procedure, while the need for TKA was able to be predicted based on WOMAC pain (p = 0.035, hazard ratio [HR] = 0.864), VAS (p = 0.008, HR = 1.131) and KOOS (p = 0.02, HR = 0.966).ConclusionsThis study revealed that several factors influenced progression to TKA, including age, KL grade, knee swelling, VAS pain and KOOS. However, there was no statistically significant difference between KL 3 and KL 4 in predicting the disease trajectory, and patients' clinical symptoms, as quantified by WOMAC pain subscale, VAS and KOOS, had a greater influence on progression to TKA than knee KL OA severity.Level of EvidenceLevel IIb.

AbstractPurposeMedial opening wedge high tibial osteotomy (MOWHTO) is a reliable joint‐preserving surgical procedure for isolated medial compartment knee osteoarthritis (OA) and overload. The aim of this study was to evaluate the long‐term survivorship and clinical outcomes of patients undergoing MOWHTO and to identify the risk factors associated with an increased risk of failure.MethodsThis was a retrospective study of prospectively collected patients who underwent MOWHTO for isolated medial OA and overload between 2002 and 2023. Clinical outcomes were evaluated using the Knee Injury and Osteoarthritis Outcome Score (KOOS) and Tegner activity score. Radiographic analysis included hip–knee–ankle (HKA) angle and medial proximal tibial angle (MPTA). Survivorship was intended from conversion to total knee arthroplasty (TKA). Logistic regression was used to identify risk factors, and p values < 0.05 were considered significant.ResultsFour hundred thirty‐one patients who underwent MOWHTO were included for analysis. Males were 82.5%, and the mean age was 49.1 ± 8.0 years. The KOOS increased in any subsection at mean 5.7 ± 4.5 years of follow‐up (p < 0.001). Complication rate was 35.9% and reoperation rate was 25.5% at mean 9.6 years of follow‐up. Removal of metal hardware due to pain and/or discomfort was the main cause of reoperation in 22% of the patients. The cumulative rate of conversion to TKA at 5 years was 2.2%, at 10 years 17.8% and at 15 years 37.1%. Age (odds ratio [OR]: 1.05, p = 0.017), wedge thickness (OR: 1.08, p = 0.015), medial femoral condyle OA (OR: 3.41, p = 0.029), medial tibial plateau OA (OR: 2.04, p = 0.044), post‐operative HKA (OR: 1.25, p = 0.031) and post‐operative MPTA (OR: 1.26, p = 0.04) were associated with an increased risk of failure.ConclusionMOWHTO yields satisfactory 10‐year survivorship in patients with medial compartment isolated knee OA and overload. Age, preoperative stage of OA, cartilage wear and post‐operative alignment are relevant patient‐related risk factors for reduced survivorship.Level of EvidenceLevel III, retrospective cohort study.

ABSTRACTPurposeAnterior cruciate ligament injury increases the risk of knee osteoarthritis, possibly via early onset of knee pain and changes in musculoskeletal function. This study compared knee muscle strength and movement biomechanics during walking and forward lunge between individuals with and without knee pain after anterior cruciate ligament reconstruction.MethodsCross‐sectional study including participants at least 3 years post anterior cruciate ligament reconstruction, aged 18–40 at the time of surgery, and body mass index ≤30. Symptomatic participants were defined by a knee pain score (reconstructed knee) of ≥3 on a 0–10 scale during activities of daily living in the past week. Asymptomatic participants were defined by a pain score of 0. Maximal isometric quadriceps and hamstring muscle strength (Nm/kg) and 3D walking, and forward lunge movement biomechanics were measured.ResultsA total of 122 participants (30% females) were included: 33 symptomatic and 89 asymptomatic (average age: 33.7, range 23.7–51.3 years). The average post‐surgery time was 6 (range 3–10) years. The symptomatic group exhibited lower isometric quadriceps and hamstring strength with mean group differences (95% confidence interval [CI]) of 0.33 (0.10 to 0.56) Nm/kg and 0.19 (0.07 to 0.31) Nm/kg, respectively. There were no important group differences in the walking and forward lunge movement biomechanics.ConclusionsSymptomatic individuals with anterior cruciate ligament reconstruction demonstrated weaker knee muscles compared to their asymptomatic counterparts. The comparable walking and forward lunge biomechanics suggest that knee pain has no substantial impact on movement biomechanics up to 10 years post‐surgery.Level of EvidenceLevel III.

AbstractPurposeIn acromioclavicular (AC) joint injuries, the kinematical interplay between the AC ligament, coracoclavicular (CC) ligaments and deltotrapezial fascia (DTF) during motions of the shoulder complex is disturbed. This study assessed kinematic alterations of sternoclavicular (SC), scapulothoracic (ST) and AC joint motion during humerothoracic and ST movements in AC injuries.MethodsShoulder girdle motion was evaluated in 14 cadaveric shoulders in 4 conditions, consisting of an intact state and AC injuries of increasing severity by sequentially sectioning the AC and CC ligaments and DTF. Joint motions were registered during humerothoracic elevation and protraction. An optical navigation system measured three‐dimensional rotations and translations in the SC, ST and AC joints.ResultsSectioning of the AC ligament increased inferior and anterior AC translation with a concomitant increase of scapular protraction. The clavicle rotated to an overall more posteriorly rotated position. Sectioning of the CC ligaments increased lateral rotation and protraction of the scapula relative to the clavicle with a concomitant inferior translation of the acromion. Also, manifest overriding of the clavicle is noted due to instability in the superoinferior and anteroposterior axes. The clavicle rotated back to an overall more anteriorly rotated position, similar to the native condition. Sectioning of the DTF further increased protraction of the scapula relative to the clavicle, while a further medial translation of the acromion under the clavicle is observed.ConclusionThe AC ligament affects anteroposterior stability, while the CC ligaments disturb stability in a superoinferior and mediolateral direction. All ligaments influence clavicular axial rotation. The DTF exacerbates alterations caused by the CC ligaments. Multiplanar decoupling results in overriding of the clavicle observed after sectioning the CC ligaments. Each sectioned ligament significantly increases scapular protraction. These findings guide further advancements in (non)surgical treatment of AC injuries to restore optimal function.Level of EvidenceN/A.

AbstractPurposeTo provide recommendations for the treatment of patients with first‐time patellar dislocation (FTPD). Part I focused on clinical presentation, symptoms, diagnosis, evaluation and imaging.MethodsFifty‐four orthopaedic surgeons and one physiotherapist from 20 countries across Europe were involved in the consensus, which was the FTPD. The consensus was performed according to the European Society for Sports Traumatology, Knee Surgery and Arthroscopy consensus methodology. The steering group designed the questions and prepared the statements based on the experience of the experts and the evidence in the literature. The statements were evaluated by the ratings of the peer‐review groups before a final consensus was released.ResultsThe consensus consists of 32 questions and statements, 13 of which will be reviewed in Part 1 of the review. There is an inverse correlation between the intensity of trauma leading to FTPD and the underlying pathoanatomic risk factors, meaning that low trauma intensity usually indicates more severe underlying abnormalities. In addition to the clinical investigation, patient age, family history, bilateral symptoms of instability and injury mechanism should be evaluated. However, reliance can be placed not only on clinical examination but also on magnetic resonance imaging scans as soon as possible, which are considered mandatory for evaluating predisposing factors such as trochlear dysplasia and patella alta and for detecting osteochondral lesions, with the exception of asymptomatic patients. Importantly, it must be recognized that in addition to recurrent instability, which affects approximately 25% of patients, a variety of symptoms are experienced by 50% of patients, such as pain, swelling, giving way, functional and psychological limitations, and a reduction in sports participation, all of which reduce their quality of life. The complications after medial patellofemoral ligament reconstruction in patients with FTPD have not yet been established; however, we know from cohorts of heterogeneous patients that the most common complications are patellofemoral pain, a reduced range of motion and patellar fracture. In total, there were 13 statements that were all accepted and achieved, 6 with strong agreements and 7 with relative agreements. The general median agreement was 8 (range 7–9). None were graded A, two were graded B, seven were graded C and 4 were graded D.ConclusionIn relation to the management of patients with first‐time patellar luxation, we have worked with 13 questions and based on these we have achieved consensus on 13 statements.Level of EvidenceLevel I, consensus.

AbstractPurposeTo investigate whether six selected anatomical variables were associated with non‐contact anterior cruciate ligament (ACL) injury in female team sport athletes.MethodsTwo hundred eighty‐seven female athletes (age 13–38 at baseline) from basketball, floorball, ice hockey and volleyball completed a baseline physical examination, including measurements of anterior‐posterior (AP) knee laxity, knee hyperextension, generalized joint hypermobility, femoral anteversion, hamstring extensibility, and navicular drop. Athletes entered the study either in 2011, 2012 or 2013 and were followed up until the end of 2015. During the follow‐up, all complete and magnetic resonance‐verified ACL injuries were recorded.ResultsTwenty‐three non‐contact ACL injuries were recorded. There were no significant differences in baseline physical examination variables between athletes who sustained ACL injuries and those who did not. However, a side‐to‐side difference in AP knee laxity greater than 2 mm was observed in 20% of the ACL injury group compared to 12% of the non‐injured group, although this difference was not statistically significant.ConclusionsIn this study, AP knee laxity, knee hyperextension, generalized joint hypermobility, femoral anteversion, hamstring extensibility and navicular drop were not associated with increased risk for non‐contact ACL injury in female team sport athletes. This study was powered to detect moderate to strong risk associations; thus, smaller risk associations may not have been identified.Level of EvidenceLevel II.

AbstractPurposeThe posterior cruciate‐retaining (CR) design offers rotational freedom but risks abnormal kinematics and instability. The medial pivot (MP) design mimics native joint motion with a high‐conformity medial and flat lateral interface. Within clinical studies, the MP design outclassed the CR design, but biomechanical studies are lacking. This study investigates the tibiofemoral and patellofemoral kinematics of both implant designs compared to native kinematics.MethodsEight fresh‐frozen cadaveric knee specimens underwent total knee arthroplasty using MP and CR designs. Testing was performed in a dynamic knee rig simulating active knee flexion (30–130°) under muscle load. Biomechanical assessments included tibial rotation, tibiofemoral translation, patellar tilt/shift, patellofemoral contact/pressure patterns and quadriceps force. Functional regressions were used to analyse the effects of the component designs on the native situation.ResultsThe MP design exhibited increased tibial rotation (130° flexion: MP 9.4° vs. CR 6.6°) and lateral anterior tibial translation during flexion (130° flexion: MP 25.8 mm vs. CR 22.6 mm). Both designs showed no significant differences in patellar tilt or shift and similar patellofemoral pressure (CR 3.2 MPa, MP 3.4 MPa) and contact patterns (CR 213.8 mm2 vs. MP 230.4 mm2). The MP design required lower quadriceps force, particularly in deep flexion (NS 452.6 N, CR 407.8 N and MP 367.3 N).ConclusionThe MP design provides a more native‐like knee kinematic profile than the CR design, with a more pronounced MP motion pattern and reduced quadriceps loading.Level of EvidenceNot applicable.

AbstractPurposeGermany has high rates of total joint arthroplasty for osteoarthritis of the knee and hip. Ambulatory health interventions can affect the progression of these conditions and the need for total joint arthroplasty. Quality indicators and guideline recommendations facilitate the transparent measurement and demonstration of care quality. Therefore, a systematic literature review of quality indicators and guideline recommendations for ambulatory care of osteoarthritis of the knee and hip before total joint arthroplasty was conducted, focusing on those that could be quantified using routine data from German statutory health insurers.MethodsFive electronic databases for quality indicators and guidelines published between 2000 and 2021 related to the ambulatory management of osteoarthritis of the knee and hip before total joint arthroplasty were searched. Two reviewers independently selected and appraised the quality of the studies. To synthesise a routine‐data‐compatible set of quality indicators, similarities and differences among existing quality indicator sets and guideline recommendations were identified and resolved.ResultsThis systematic search yielded 10,841 potentially relevant records, leading to the identification of 20 sets of quality indicators and 35 guidelines with measures quantifiable using routine data. The present evidence synthesis produced 24 routine‐data‐compatible process quality indicators related to the type, order or frequency of musculoskeletal appointments, diagnostic imaging procedures, referrals to physical therapists and pharmaceutical prescriptions.ConclusionThe synthesised set of routine‐data‐compatible quality indicators can provide a resource‐saving tool for offering individual feedback to physicians on the processes involved in the ambulatory management of osteoarthritis of the knee and hip. Engaging in interdisciplinary discussions on variations in quality indicator outcomes could contribute to improving interdisciplinary physician collaboration in ambulatory care for these conditions.Level of EvidenceLevel III.

AbstractPurposePreoperative planning for medial open wedge high tibial osteotomies (HTOs) and lateral open wedge distal femur osteotomies (DFOs) commonly uses wedge height to guide accurate correction. However, it is unclear if this parameter is influenced by intraoperative variations in osteotomy entry point or length. This study hypothesized that wedge angle remains constant during planning, while wedge height varies depending on hinge or entry points.MethodsWhole leg radiographs of 40 patients who underwent HTO or DFO (2018–2024) were analysed using digital planning software. For each HTO and DFO case, 27 and 21 osteotomy variants were created, respectively, by altering entry and hinge points, resulting in 960 simulations. Wedge angle, wedge height and osteotomy depth were measured for each variant. Correlations and regression analyses assessed the relationships among these variables, and a mathematical formula was developed to predict wedge height from wedge angle and osteotomy depth.ResultsWedge angle remained consistent across variants (mean deviation: 0.1 ± 0.1°), while wedge height showed variability (mean deviation: 0.7 ± 0.5 mm) influenced by entry and hinge points. Significant correlations were found between wedge height and opening angle (R = 0.83, p < 0.001) and osteotomy depth (R = 0.60, p < 0.001). Predicted wedge height closely matched actual values (R = 0.998, p < 0.001), with minimal error (−0.01 ± 0.1°).ConclusionThis study highlights that relying solely on wedge height for osteotomy planning in HTO and DFO is insufficient due to variations in entry and hinge points. The hinge angle proved to be the most reliable parameter. Intraoperative osteotomy depth measurements can help adjust wedge height for accurate limb alignment when deviations occur.Level of EvidenceLevel V simulation study.

AbstractPurposeAlthough personalised alignment has become popular in total knee arthroplasty (TKA), it is unclear which workflow and alignment strategy best restores the bony and laxity phenotype and whether this varies between knee phenotypes. The aim of this study was, therefore, to develop a three‐dimensional (3D) scoring system which assesses bony anatomy, laxity and alignment parameters for TKA. This novel 3D scoring system was tested using a validated TKA simulator on three different knee phenotypes with various alignment workflows. 3D scores were compared between phenotypes and workflows.MethodsIn this 3D scoring system, analyses of bony resections of all six joint planes were included (maximum score for anatomical resections ± 1 mm) as well as joint laxity/gap analysis (maximum score for balanced extension/flexion gap, medial and lateral side ± 2 mm). Additional alignment parameters (hip–knee–ankle angle, medial proximal tibial angle, lateral distal femoral angle, Tibia slope and coronal plane alignment of the knee) were integrated. All data points were obtained from preoperative long leg x‐rays, intraoperative gap analysis with CAS and intraoperative cartilage measurements. The maximum score for all categories was 27 points (12/10/5).The 3D scores were analysed for nine knees with three knee phenotypes (neutral, varus and valgus) with six different alignment workflows (mechanical alignment—femur first, adjusted mechanical alignment—femur first, unrestricted kinematic alignment, restricted kinematic alignment, inverse kinematic alignment and functional alignment‐tibia first) using the Knee‐computational alignment trainer simulator. Comparison between workflows in all phenotypes was performed for each category.ResultsIn neutral phenotypes, all alignment workflows, including mechanical alignment, showed similar high mean scores. In varus and valgus phenotypes, personalised alignment workflows scored higher than systematic workflows. While in varus phenotypes, scoring of personalised alignment workflows was similarly high to that in straight knees phenotypes, it showed lower means in valgus phenotypes. Measured‐resection workflows restored bony phenotypes in a higher percentage while gap‐balanced workflows performed better in the category of laxity/gap balance. None of the personalised workflows performed best in all knees.ConclusionsThe new 3D scoring system for individual knee phenotype restoration in TKA allowed a quantitative analysis of the individual reconstruction of the bony and laxity anatomy in different knee phenotypes. First preliminary results show that personalised alignment workflows perform better than systematic mechanical alignment in varus and valgus phenotypes, while in neutral phenotypes, the difference was minimal. None of the personalised workflows scored best in all knees, showing the potential for a 3D phenotype workflow including more bony alignment and laxity parameters. Testing of this 3D scoring system in a larger series of cases is crucial to prove the concept and test correlations between 3D scores and clinical outcomes.Level of EvidenceLevel IIa.

AbstractCurrent anterior cruciate ligament reconstruction (ACLR) rehabilitation practice guidelines lack updates in key areas: open kinetic chain (OKC) quadriceps strengthening, neurocognitive training and psychological interventions. Recent research shows that OKC exercises, when combined with closed kinetic chain exercises, improve strength without compromising graft integrity, though careful monitoring for knee pain and effusion is essential. Neurocognitive training, targeting reaction times, visual attention and dual‐tasking, is promising for reducing reinjury risk but remains underutilized. Similarly, psychological responses, often assessed via patient‐reported outcomes, are a critical part of the recovery process after ACLR, but how to address these responses for the individual patient remains unclear, emphasizing the need for individualized support. The European Society for Sports Traumatology, Knee Surgery, and Arthroscopy (ESSKA) is developing an ACL rehabilitation consensus to integrate these insights into actionable, evidence‐based guidelines, ensuring tailored, patient‐centered care that optimizes recovery and reduces reinjury risks.Level of EvidenceLevel V.

AbstractPurposeDeveloping large‐scale, standardized radiographic registries for anterior cruciate ligament (ACL) injuries with artificial intelligence (AI) tools can enhance personalized orthopaedics. We propose deploying Artificial Intelligence for Knee Imaging Registration and Analysis (AKIRA), a trio of deep learning (DL) algorithms, to automatically classify and annotate radiographs. We hypothesize that algorithms can efficiently organize radiographs based on laterality, projection, identify implants and classify osteoarthritis (OA) grade.MethodsA collection of 20,836 knee radiographs from all time points of treatment (mean orthopaedic follow‐up 70.7 months; interquartile range [IQR]: 6.8–172 months) were aggregated from 1628 ACL‐injured patients (median age 26 years [IQR: 19–42], 57% male). Three DL algorithms (EfficientNet, YOLO [You Only Look Once] and Residual Network) were employed. Radiograph laterality and projection (anterior‐posterior [AP], lateral, sunrise, posterior‐anterior, hip–knee–ankle and Camp‐Coventry intercondylar [notch]) were labelled by a DL model. Manually provided labels of metal fixation implants were used to develop a DL object detection algorithm. The degree of OA, both as measured by specific Kellgren–Lawrence (KL) grades, as well as based on a binarized label of OA (defined as KL Grade ≥2), on standing AP radiographs were classified using a DL algorithm. Individual model performances were evaluated on a subset of images prior to the deployment of AKIRA to registry construction using all ACL radiographs.ResultsThe classification algorithms showed excellent performance in classifying radiographic laterality (F1 score: 0.962–0.975) and projection (F1 score: 0.941–1.0). The object detection algorithm achieved high precision–recall (area under the precision‐recall curve: 0.695–0.992) for identifying various metal fixations. The KL classifier reached concordances of 0.39–0.40, improving to 0.81–0.82 for binary OA labels. Sequential deployment of AKIRA following internal validation processed and labelled all 20,836 images with the appropriate views, implants, and the presence of OA within 88 min.ConclusionAKIRA effectively automated the classification and object detection in a large radiograph cohort of ACL injuries, creating an AI‐enabled radiographic registry with comprehensive details on laterality, projection, implants and OA.Study DesignCross‐sectional study.Level of EvidenceLevel IV.