IF 2 4区医学 Q3 ORTHOPEDICS

Knee

Pub Date : 2026-03-01 Epub Date: 2025-12-26 DOI: 10.1016/j.knee.2025.104306

Ryota Yamagami, Shuji Taketomi, Kenichi Kono, Kohei Kawaguchi, Ryo Murakami, Takashi Kobayashi, Tomoki Murakami, Sora Koiwa, Sakae Tanaka

Background

The N test, an extension-based maneuver, reportedly elicited greater tibial acceleration than the pivot shift test in anterior cruciate ligament (ACL)-deficient (ACLD) knees. However, its utility in ACL-reconstructed (ACLR) knees, where residual instability is subtle, remains unclear. This study compared tibial acceleration between the N test and pivot shift test in ACLD and ACLR knees and assessed correlation with clinical grading.

Methods

A total of 103 knees (68 ACLD, 35 ACLR) were evaluated under general anesthesia. A triaxial inertial sensor was placed on the anterolateral tibia, and peak-to-peak anteroposterior acceleration was extracted as the sole quantitative parameter, interpreted as a surrogate for combined anterior subluxation and external rotation of the lateral tibial compartment. Each maneuver was performed five times; the mean of the central three trials was analyzed. Paired t-tests and Spearman’s rank correlation were used.

Results

In ACLD knees, the injured limb showed significantly greater acceleration than the uninjured limb in both tests (N test, 8.32 ± 4.08 vs 4.53 ± 2.49 m/s²; pivot shift, 6.11 ± 4.41 vs 3.17 ± 2.75 m/s²; both, P < 0.001). The N test induced greater acceleration than the pivot shift test in both ACLD and ACLR knees (ACLR, 4.26 ± 1.68 vs 2.68 ± 2.04 m/s²; both, P < 0.001). N test–induced acceleration correlated with IKDC grading (ACLR. r = 0.577; ACLD, r = 0.575; overall, r = 0.733; all P < 0.001).

Conclusions

The N test elicited greater tibial acceleration than the pivot shift test and correlated strongly with clinical grading, even in ACLR knees, supporting its potential as a sensitive supplementary tool for detecting subtle residual laxity after ACL reconstruction.

Level of Evidence: Level III, diagnostic study.

背景：据报道，在前交叉韧带（ACL）缺陷（ACLD）膝盖中，N试验是一种基于伸展的操作，比枢轴移位试验引起更大的胫骨加速度。然而，其在残余不稳定微妙的ACLR重建（ACLR）膝关节中的应用仍不清楚。本研究比较了ACLD和ACLR膝关节N试验和枢轴移位试验的胫骨加速度，并评估了与临床分级的相关性。方法全麻下对103例膝关节（ACLD 68例，ACLR 35例）进行评估。在胫骨前外侧放置一个三轴惯性传感器，提取峰对峰前后加速度作为唯一的定量参数，解释为胫骨外侧室联合前路半脱位和外旋的替代指标。每个动作做5次；对中心三项试验的平均值进行分析。采用配对t检验和Spearman等级相关。结果在ACLD膝关节中，两项试验中损伤肢加速度均显著大于未损伤肢（N试验，8.32±4.08 vs 4.53±2.49 m/s2；枢轴位移，6.11±4.41 vs 3.17±2.75 m/s2， P均为0.001）。在ACLD和ACLR中，N试验诱导的加速度均大于枢轴移位试验（ACLR, 4.26±1.68 vs 2.68±2.04 m/s2；均P <； 0.001）。N试验诱导加速度与IKDC分级（ACLR）相关。r = 0.577；ACLD, r = 0.575；总体而言，r = 0.733；P < 0.001)。结论N试验比枢轴移位试验引起更大的胫骨加速度，并且与临床分级密切相关，即使在ACLR膝关节中也是如此，支持其作为检测ACL重建后细微残余松弛的敏感补充工具的潜力。证据等级：III级，诊断性研究。

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引用次数: 0

Paediatric Knee Surgery: A New Frontier in Orthopaedics 儿科膝关节手术：骨科的新前沿

IF 2 4区医学 Q3 ORTHOPEDICS

Knee

Pub Date : 2026-03-01 Epub Date: 2025-12-19 DOI: 10.1016/j.knee.2025.104310

Adil Ajuied , Fazal Ali , Nicolas Nicolaou

引用次数: 0

Mechanism of muscle activation in the protection of knee joint injury during jogging 慢跑时肌肉激活保护膝关节损伤的机制

IF 2 4区医学 Q3 ORTHOPEDICS

Knee

Pub Date : 2026-03-01 Epub Date: 2025-12-20 DOI: 10.1016/j.knee.2025.104307

Jiangtao Ruan , Kai Cui , Yangyang Meng , Xia Xiao

Background

It is important to understand the role of muscle activation in knee joint protection against the injuries, such as meniscus tear, cartilage wear, and ligament damage, often caused by muscle weakness, improper running posture, or overtraining. Research on the finite element knee model with muscles has not been reported yet, nor have there been any biomechanical explorations on the internal tissues of knee joint with muscle activation.

Objective

To explore the mechanism of muscle activation in jogging for the protection against knee joint injuries based on the stress fields of the knee internal tissues.

Methods

A finite element knee joint model with muscles (Vastus lateralis, vastus medialis, and vastus intermedius) was established. The stress fields of knee internal tissues during jogging were numerically simulated and investigated to explore the mechanism of muscle activation in knee protection against injury.

Results

Activation of muscle forces reduces peak stress on joint tissues, diminishes stress concentration, and enhances the load-bearing capacity of the knee joint. The proportion of contact area in the lateral tissues is increased, which means activating the muscle forces adjusts the load-bearing mode of the knee joint by involving the lateral tissues to participate in sharing the loads with the medial tissues, thus improve the stability of the knee joint.

Conclusion

Activation of muscle forces in jogging improves the load-bearing capacity and stability of the knee joint by reducing peak stress on joint tissues, decreasing the proportion of concentrated area, increasing the contact area in lateral tissues, and involving lateral tissues in sharing loads with medial tissues.

了解肌肉激活在膝关节保护中所起的作用是很重要的，这些损伤通常是由肌肉无力、不正确的跑步姿势或过度训练引起的，如半月板撕裂、软骨磨损和韧带损伤。对有肌肉的膝关节有限元模型的研究尚未见报道，对有肌肉激活的膝关节内部组织的生物力学探索也尚未见报道。目的从膝关节内部组织应力场的角度探讨慢跑时肌肉激活对膝关节损伤的保护作用机制。方法建立具有股外侧肌、股内侧肌和股中间肌的膝关节有限元模型。通过数值模拟和研究慢跑时膝关节内部组织的应力场，探讨肌肉激活在膝关节损伤保护中的作用机制。结果肌肉力量的激活降低了关节组织的峰值应力，减少了应力集中，提高了膝关节的承重能力。外侧组织接触面积的比例增加，即激活肌力，通过外侧组织参与与内侧组织分担负荷，调整膝关节的承重方式，从而提高膝关节的稳定性。结论慢跑时肌肉力量的激活，通过降低关节组织的峰值应力、减少集中面积的比例、增加外侧组织的接触面积、使外侧组织与内侧组织分担负荷，提高膝关节的负重能力和稳定性。

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引用次数: 0

Comparisons of muscle strength and power in females with above and below average hamstrings-to-quadriceps ratio across the velocity spectrum 在速度谱中，腿筋与股四头肌之比高于和低于平均水平的女性肌肉力量和力量的比较

IF 2 4区医学 Q3 ORTHOPEDICS

Knee

Pub Date : 2026-03-01 Epub Date: 2025-12-20 DOI: 10.1016/j.knee.2025.104299

Samantha Searles , Adam Knight , Harish Chander , Zachary Gillen

Background/purpose

Females with above average hamstrings-to-quadriceps ratio (HTQ) will have superior peak torque (PT), mean power (MP), and HTQ compared to those with below average HTQ.

Methods

27 college-aged females participated. PT and MP was taken from maximal voluntary isometric contractions (MVICs) and isokinetic knee extensions and flexions performed at 60–300°·s⁻¹ for each leg. HTQ was the ratio of PT from knee flexion and extension. Subjects were separated into above and below average HTQ groups for each leg and velocity. ANOVAs examined differences in HTQ, PT, and MP across groups and velocities.

Results

The above average group had greater HTQ across velocity (p ≤ 0.002) but both groups had the same response where HTQ was the same from MVIC-60°·s⁻¹, increased from 60 to 120°·s⁻¹, and plateaued 120–300°·s⁻¹. Knee extension PT was greater for the below average group (p < 0.030). For both groups, PT decreased across velocity (p ≤ 0.005). Knee flexion PT was highest at MVIC followed by a decrease from 60 to 300°·s⁻¹ for all groups (p < 0.001). For both groups, PT decreased across velocity (p < 0.005). Knee extension MP was greater for the below average group (p < 0.001). For both groups, MP increased from 60 to 180°·s⁻¹ (p < 0.001) and plateaued from 180 to 300°·s⁻¹ (p = 1.000). Knee flexion MP was greater for the above average group (p ≤ 0.013). For both groups, MP increased from 60 to 120°·s⁻¹ (p < 0.001), plateaued from120 to 240°·s⁻¹ (p = 1.000), decreased from 240 to 300°·s⁻¹ (p > 0.426).

Conclusions

Above or below HTQ has minimal impact on torque and power production as velocity increases, and should be used with other metrics for injury risk.

背景/目的：与低于平均水平的女性相比，腿筋与股四头肌之比（HTQ）高于平均水平的女性将具有更高的峰值扭矩（PT）、平均功率（MP）和HTQ。方法27名女大学生参与。PT和MP取自每条腿在60-300°·s−1下进行的最大自主等距收缩（mvic）和等速膝关节伸展和屈曲。HTQ为膝关节屈伸PT的比值。每条腿和速度将受试者分为高于和低于平均HTQ组。方差分析分析了不同组和速度之间HTQ、PT和MP的差异。结果上述平均组的HTQ跨速度较大（p≤0.002），但两组的反应相同，从MVIC-60°·s−1开始HTQ从60°·s−1增加到120°·s−1，并稳定在120°- 300°·s−1。低于平均水平组的膝关节伸展PT更大（p < 0.030）。两组PT均随速度变化而降低（p≤0.005）。所有组的膝关节屈曲PT在MVIC时最高，随后从60°·s−1降至300°·s−1 （p < 0.001）。两组PT均随速度变化而降低（p < 0.005）。低于平均水平组的膝关节伸展MP更大（p < 0.001）。两组的MP均从60°·s−1增加到180°·s−1 (p < 0.001)，并在180°·s−1至300°·s−1之间保持稳定（p = 1.000）。膝关节屈曲MP高于平均水平组（p≤0.013）。两组的MP均从60°·s−1增加到120°·s−1 (p > 0.001)，从120°·s−1增加到240°·s−1 (p = 1.000)，从240°·s−1减少到300°·s−1 （p > 0.426）。结论随着速度的增加，高于或低于HTQ对扭矩和功率产生的影响最小，应与其他伤害风险指标一起使用。

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引用次数: 0

Response to letter to the editor to: “ChatGPT delivers satisfactory responses to the most frequent questions on meniscus surgery” 回复致编辑的信：“ChatGPT对半月板手术中最常见的问题提供了令人满意的答复”。

IF 2 4区医学 Q3 ORTHOPEDICS

Knee

Pub Date : 2026-03-01 Epub Date: 2026-01-03 DOI: 10.1016/j.knee.2025.104316

Felix Winden , Markus Bormann , Fabian Gilbert , Boris Michael Holzapfel , Daniel Patrick Berthold

引用次数: 0

Knee osteoarthritis – Current concepts 膝骨关节炎——当前的概念

IF 2 4区医学 Q3 ORTHOPEDICS

Knee

Pub Date : 2026-03-01 Epub Date: 2026-02-11 DOI: 10.1016/j.knee.2026.104369

Oday Al-Dadah (Editors-in-Chief), Caroline Hing

引用次数: 0

Inter-examiner and inter-day reliability of dynamic tibiofemoral movements measurement using motion capture during walking and jumping tasks 在行走和跳跃任务中使用动作捕捉的动态胫股运动测量的主考人间和日间可靠性

IF 2 4区医学 Q3 ORTHOPEDICS

Knee

Pub Date : 2026-03-01 Epub Date: 2026-01-03 DOI: 10.1016/j.knee.2025.104321

Tom Vendrig, Michèle N.J. Keizer, Han Houdijk

Background

The anterior cruciate ligament (ACL) primarily restricts dynamic anterior tibia translation (ATTd) and internal tibia rotation (ITRd). Measuring these movements dynamically is essential for evaluating injury risk factors and their potential consequences. This study aimed to assess the inter-examiner and inter-day reliability of measuring ATTd and ITRd during walking and jumping tasks using optoelectronic motion capture.

Methods

Nineteen healthy participants performed walking, side hop, single-leg hop for distance, and triple hop for distance. To assess inter-examiner reliability, tasks were repeated on the same day: once after the first examiner placed markers and once after the second examiner. To assess inter-day reliability, tasks were repeated on a second day. Pointwise intraclass correlation coefficient (ICC) and standard error of measurement (SEM) values were assessed across the stance phase of walking and the jump-landing phases.

Results

For walking, ICC values over the stance phase indicated good-to-excellent reliability for ATTd and ITRd (ICC = 0.66–0.82), with SEM values below 3.2 mm and 2.8° (≤19 % of range of motion). For all jumping tasks, ICC values over the entire landing indicated excellent reliability for ATTd and ITRd (ICC = 0.75–0.86), with higher inter-examiner compared with inter-day reliability. The phase around peak ground reaction force demonstrated superior reliability compared with the entire landing, with SEM values below 2.6 mm and 2.2° (≤17 % of range of motion, except for ATTd during the side hop).

Conclusion

Results suggest adequate reliability of ATTd and ITRd for research assessing ACL injury risk factors and outcomes of various surgical and rehabilitation methods following ACL injury.

背景：前交叉韧带（ACL）主要限制动态胫骨前平移（ATTd）和胫骨内旋转（ITRd）。动态测量这些运动对于评估损伤风险因素及其潜在后果至关重要。本研究旨在评估光电动作捕捉在行走和跳跃任务中测量ATTd和ITRd的人间和日间可靠性。方法19名健康受试者分别进行步行、侧跳、单腿远跳和三腿远跳。为了评估考官之间的信度，任务在同一天重复：第一个考官打分后一次，第二个考官打分后一次。为了评估白天的可靠性，在第二天重复了这些任务。在行走的站立阶段和起跳落地阶段评估点向类内相关系数（ICC）和测量标准误差（SEM）值。结果对于行走，站位阶段的ICC值显示出良好到优异的可靠性（ICC = 0.66-0.82）， SEM值低于3.2 mm和2.8°（≤运动范围的19%）。对于所有的跳跃任务，整个着陆过程的ICC值表明，ATTd和ITRd的可靠性非常好（ICC = 0.75-0.86），与日间可靠性相比，中间可靠性更高。与整个着陆过程相比，峰值地面反力附近的相位显示出更高的可靠性，SEM值低于2.6 mm和2.2°（≤17%的运动范围，侧跳期间的ATTd除外）。结论atd和ITRd在评估ACL损伤的危险因素以及ACL损伤后各种手术和康复方法的结果方面具有足够的可靠性。

{"title":"Inter-examiner and inter-day reliability of dynamic tibiofemoral movements measurement using motion capture during walking and jumping tasks","authors":"Tom Vendrig, Michèle N.J. Keizer, Han Houdijk","doi":"10.1016/j.knee.2025.104321","DOIUrl":"10.1016/j.knee.2025.104321","url":null,"abstract":"<div><h3>Background</h3><div>The anterior cruciate ligament (ACL) primarily restricts dynamic anterior tibia translation (ATTd) and internal tibia rotation (ITRd). Measuring these movements dynamically is essential for evaluating injury risk factors and their potential consequences. This study aimed to assess the inter-examiner and inter-day reliability of measuring ATTd and ITRd during walking and jumping tasks using optoelectronic motion capture.</div></div><div><h3>Methods</h3><div>Nineteen healthy participants performed walking, side hop, single-leg hop for distance, and triple hop for distance. To assess inter-examiner reliability, tasks were repeated on the same day: once after the first examiner placed markers and once after the second examiner. To assess inter-day reliability, tasks were repeated on a second day. Pointwise intraclass correlation coefficient (ICC) and standard error of measurement (SEM) values were assessed across the stance phase of walking and the jump-landing phases.</div></div><div><h3>Results</h3><div>For walking, ICC values over the stance phase indicated good-to-excellent reliability for ATTd and ITRd (ICC = 0.66–0.82), with SEM values below 3.2 mm and 2.8° (≤19 % of range of motion). For all jumping tasks, ICC values over the entire landing indicated excellent reliability for ATTd and ITRd (ICC = 0.75–0.86), with higher inter-examiner compared with inter-day reliability. The phase around peak ground reaction force demonstrated superior reliability compared with the entire landing, with SEM values below 2.6 mm and 2.2° (≤17 % of range of motion, except for ATTd during the side hop).</div></div><div><h3>Conclusion</h3><div>Results suggest adequate reliability of ATTd and ITRd for research assessing ACL injury risk factors and outcomes of various surgical and rehabilitation methods following ACL injury.</div></div>","PeriodicalId":56110,"journal":{"name":"Knee","volume":"59 ","pages":"Article 104321"},"PeriodicalIF":2.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145885443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Rounded-rectangular bone tunnels enhance early tendon–bone healing and limit tunnel enlargement in a rabbit anterior cruciate ligament reconstruction with quadriceps tendon graft model 圆形矩形骨隧道促进早期肌腱-骨愈合和限制隧道扩大兔前交叉韧带重建四头肌肌腱移植模型

IF 2 4区医学 Q3 ORTHOPEDICS

Knee

Pub Date : 2026-03-01 Epub Date: 2025-12-18 DOI: 10.1016/j.knee.2025.104309

Naoki Takemoto, Junsuke Nakase, Yasushi Takata, Yusuke Yanatori, Manase Nishimura, Kentaro Fujita, Mikino Saito, Satoru Demura

Purpose

To determine whether rounded-rectangular bone tunnels matching the flat morphology of a quadriceps tendon (QT) graft enhance early tendon–bone healing (TBH) and suppress bone-tunnel enlargement (BTE) after anterior cruciate ligament (ACL) reconstruction in a rabbit model.

Methods

Female Japanese White rabbits underwent ACL reconstruction with a QT graft and were randomized into circular or rounded-rectangular tunnels. Knees were evaluated at 4, 8, and 12 weeks (n = 10/group/time point; total, 60). Micro–computed tomography quantified tunnel cross-sectional area and flattening ratio, with BTE (%) calculated vs. baseline. Histological TBH at the tendon–bone interface was semi-quantitatively scored (n = 4/group/time point), and biomechanical testing assessed maximum failure load and mode of failure (n = 6/group/time point). Non-parametric tests were used to compare groups, and repeated-measures analysis of variance was used to assess temporal changes.

Results

The rounded-rectangular tunnel group (Group R) showed significantly lower BTE than the circular tunnel group (Group C) at 4 and 8 weeks (both p < 0.05). Flattening ratios did not differ between groups at 4–12 weeks. In both groups, tunnel area increased from time 0 to a peak at 4 weeks and then slightly decreased and stabilized by 8–12 weeks. The histological scores favored Group R at 4 weeks (P = 0.038). The maximum failure load was higher in Group R at 4 weeks (P = 0.03).

Conclusion

Matching QT grafts with rounded-rectangular tunnels suppresses early BTE and enhances early histological integration and fixation strength after ACL reconstruction, potentially enabling safer and earlier rehabilitation.

目的探讨兔前交叉韧带（ACL）重建后圆形-矩形骨隧道是否与股四头肌肌腱（QT）的扁平形态相匹配，从而促进早期肌腱-骨愈合（TBH）并抑制骨隧道扩大（BTE）。方法用QT移植重建雌性日本大白兔前交叉韧带，随机分为圆形或圆矩形隧道。在第4周、第8周和第12周对膝关节进行评估（n = 10/组/时间点；总计60）。显微计算机断层扫描量化了隧道横截面积和平坦率，计算了BTE（%）与基线的对比。对肌腱-骨界面的组织学TBH进行半定量评分（n = 4/组/时间点），生物力学测试评估最大破坏载荷和破坏模式（n = 6/组/时间点）。非参数检验用于组间比较，重复测量方差分析用于评估时间变化。结果圆形矩形隧道组（R组）在4周和8周时BTE显著低于圆形隧道组（C组）（p < 0.05）。在4-12周时，各组间的扁平率无差异。两组患者的隧道面积均从0时开始增加，4周时达到峰值，8-12周时略有下降并趋于稳定。4周时R组组织学评分优于对照组（P = 0.038）。第4周时，R组最大失效负荷较高（P = 0.03）。结论圆矩形隧道匹配QT移植物抑制了早期BTE，增强了ACL重建后早期组织整合和固定强度，可能实现更安全和更早的康复。

{"title":"Rounded-rectangular bone tunnels enhance early tendon–bone healing and limit tunnel enlargement in a rabbit anterior cruciate ligament reconstruction with quadriceps tendon graft model","authors":"Naoki Takemoto, Junsuke Nakase, Yasushi Takata, Yusuke Yanatori, Manase Nishimura, Kentaro Fujita, Mikino Saito, Satoru Demura","doi":"10.1016/j.knee.2025.104309","DOIUrl":"10.1016/j.knee.2025.104309","url":null,"abstract":"<div><h3>Purpose</h3><div>To determine whether rounded-rectangular bone tunnels matching the flat morphology of a quadriceps tendon (QT) graft enhance early tendon–bone healing (TBH) and suppress bone-tunnel enlargement (BTE) after anterior cruciate ligament (ACL) reconstruction in a rabbit model.</div></div><div><h3>Methods</h3><div>Female Japanese White rabbits underwent ACL reconstruction with a QT graft and were randomized into circular or rounded-rectangular tunnels. Knees were evaluated at 4, 8, and 12 weeks (<em>n</em> = 10/group/time point; total, 60). Micro–computed tomography quantified tunnel cross-sectional area and flattening ratio, with BTE (%) calculated vs. baseline. Histological TBH at the tendon–bone interface was semi-quantitatively scored (<em>n</em> = 4/group/time point), and biomechanical testing assessed maximum failure load and mode of failure (<em>n</em> = 6/group/time point). Non-parametric tests were used to compare groups, and repeated-measures analysis of variance was used to assess temporal changes.</div></div><div><h3>Results</h3><div>The rounded-rectangular tunnel group (Group R) showed significantly lower BTE than the circular tunnel group (Group C) at 4 and 8 weeks (both <em>p</em> < 0.05). Flattening ratios did not differ between groups at 4–12 weeks. In both groups, tunnel area increased from time 0 to a peak at 4 weeks and then slightly decreased and stabilized by 8–12 weeks. The histological scores favored Group R at 4 weeks (<em>P</em> = 0.038). The maximum failure load was higher in Group R at 4 weeks (<em>P</em> = 0.03).</div></div><div><h3>Conclusion</h3><div>Matching QT grafts with rounded-rectangular tunnels suppresses early BTE and enhances early histological integration and fixation strength after ACL reconstruction, potentially enabling safer and earlier rehabilitation.</div></div>","PeriodicalId":56110,"journal":{"name":"Knee","volume":"59 ","pages":"Article 104309"},"PeriodicalIF":2.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145771994","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A bounded functional alignment approach for total knee arthroplasty: impact on knee phenotype and patient-reported outcomes 全膝关节置换术的有限功能对齐方法：对膝关节表型的影响和患者报告的结果

IF 2 4区医学 Q3 ORTHOPEDICS

Knee

Pub Date : 2026-03-01 Epub Date: 2025-12-26 DOI: 10.1016/j.knee.2025.104313

Hallie B. Remer , Chukwuemeka U. Osondu , Hannah Mosher , Yvette Hernandez , Giovanni Paraliticci , Charles M. Lawrie , Juan C. Suarez

Background

Native knee coronal alignment and joint line obliquity vary among individuals as evidenced by the Coronal Plane Alignment of the Knee (CPAK) classification. This study investigated whether a single institution’s functional alignment (FA) approach during robotic-assisted total knee arthroplasty (TKA) preserves native knee phenotypes and whether knee phenotype retention impacts patient-reported outcomes (PROs).

Methods

We performed a retrospective cohort study of 188 patients who underwent robotic TKA with a bounded FA strategy at a single institution. Surgeons were blinded to preoperative knee phenotypes and employed an FA technique with minimized soft tissue releases. Knees were grouped as retention or reclassification of preoperative CPAK phenotype. PROs were analyzed at 1-year follow up, including minimal clinically important difference (MCID) achievement.

Results

The most common preoperative CPAK knee phenotypes were classes I (30.3 %), II (36.2 %), and III (23.9 %). Postoperatively, 74.5 % of knees retained their native phenotype, including 100 % of class I and 89 % of class III knees. Most common postoperative CPAK knee phenotypes were classes I (48.4 %) and III (23.4 %) followed by class II (20.7 %). No significant differences were identified in any PROs at 1-year follow up between retention groups (Knee injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR): 26.4 vs. 29.4, P = 0.36). Similar proportions of both groups achieved MCID thresholds for KOOS JR and PROMIS-10 scores.

Conclusion

A bounded FA approach to robotic assisted TKA retained native CPAK phenotype in most cases, though phenotype retention did not significantly affect 1-year PROs. Within bounded FA parameters, soft tissue balance may be as important as precise phenotype restoration for short-term functional outcomes.

膝关节的冠状面对齐（CPAK）分类证明了个体间膝关节的冠状面对齐和关节线倾角的差异。本研究调查了在机器人辅助全膝关节置换术（TKA）中单一机构的功能对齐（FA）方法是否保留了原始膝关节表型，以及膝关节表型保留是否影响患者报告的结果（PROs）。方法：我们进行了一项回顾性队列研究，188名患者在同一机构接受了有界FA策略的机器人TKA。外科医生对术前膝关节表型不知情，并采用最小化软组织释放的FA技术。膝关节按术前CPAK表型保留或再分类进行分组。在1年的随访中分析PROs，包括最小临床重要差异（MCID）成就。结果术前最常见的CPAK膝关节表型为I型（30.3%）、II型（36.2%）和III型（23.9%）。术后，74.5%的膝关节保持原有表型，包括100%的I级膝关节和89%的III级膝关节。最常见的术后CPAK膝关节表型为I类（48.4%）和III类（23.4%），其次是II类（20.7%）。在1年随访中，保留组之间的任何pro均无显著差异（膝关节损伤和骨关节炎关节置换术结局评分（oos JR）： 26.4比29.4,P = 0.36）。在KOOS JR和promise -10评分中，两组达到MCID阈值的比例相似。结论机器人辅助TKA的有限FA方法在大多数情况下保留了原生CPAK表型，尽管表型保留对1年PROs没有显著影响。在限定FA参数内，对于短期功能结果，软组织平衡可能与精确的表型恢复一样重要。

{"title":"A bounded functional alignment approach for total knee arthroplasty: impact on knee phenotype and patient-reported outcomes","authors":"Hallie B. Remer , Chukwuemeka U. Osondu , Hannah Mosher , Yvette Hernandez , Giovanni Paraliticci , Charles M. Lawrie , Juan C. Suarez","doi":"10.1016/j.knee.2025.104313","DOIUrl":"10.1016/j.knee.2025.104313","url":null,"abstract":"<div><h3>Background</h3><div>Native knee coronal alignment and joint line obliquity vary among individuals as evidenced by the Coronal Plane Alignment of the Knee (CPAK) classification. This study investigated whether a single institution’s functional alignment (FA) approach during robotic-assisted total knee arthroplasty (TKA) preserves native knee phenotypes and whether knee phenotype retention impacts patient-reported outcomes (PROs).</div></div><div><h3>Methods</h3><div>We performed a retrospective cohort study of 188 patients who underwent robotic TKA with a bounded FA strategy at a single institution. Surgeons were blinded to preoperative knee phenotypes and employed an FA technique with minimized soft tissue releases. Knees were grouped as retention or reclassification of preoperative CPAK phenotype. PROs were analyzed at 1-year follow up, including minimal clinically important difference (MCID) achievement.</div></div><div><h3>Results</h3><div>The most common preoperative CPAK knee phenotypes were classes I (30.3 %), II (36.2 %), and III (23.9 %). Postoperatively, 74.5 % of knees retained their native phenotype, including 100 % of class I and 89 % of class III knees. Most common postoperative CPAK knee phenotypes were classes I (48.4 %) and III (23.4 %) followed by class II (20.7 %). No significant differences were identified in any PROs at 1-year follow up between retention groups (Knee injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR): 26.4 vs. 29.4, <em>P</em> = 0.36). Similar proportions of both groups achieved MCID thresholds for KOOS JR and PROMIS-10 scores.</div></div><div><h3>Conclusion</h3><div>A bounded FA approach to robotic assisted TKA retained native CPAK phenotype in most cases, though phenotype retention did not significantly affect 1-year PROs. Within bounded FA parameters, soft tissue balance may be as important as precise phenotype restoration for short-term functional outcomes.</div></div>","PeriodicalId":56110,"journal":{"name":"Knee","volume":"59 ","pages":"Article 104313"},"PeriodicalIF":2.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145841710","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Fixed versus mobile bearing medial unicompartmental knee arthroplasty with the same femoral implant design: a randomised controlled trial with a minimum of 10-year follow-up 采用相同股骨植入物设计的固定与移动承重内侧单室膝关节置换术：一项至少10年随访的随机对照试验。

IF 2 4区医学 Q3 ORTHOPEDICS

Knee

Pub Date : 2026-03-01 Epub Date: 2025-12-23 DOI: 10.1016/j.knee.2025.104304

Konstantinos Tsikopoulos , Konstantinos Kazamias , Paul White , James Robinson , John Newman , Andrew Porteous , James Murray

Background

The optimal bearing surface design for medial unicompartmental knee arthroplasty (UKA) has yet to be determined. In this randomised controlled trial from a single institution, we aimed to compare the clinical outcome, complications and joint survival of a single design femoral component medial UKA with either a fixed or mobile bearing tibial component from the same (Corin AMC, later rebranded Uniglide) implant system.

Methods

This was a prospective randomised trial with patients randomised to either fixed or mobile tibial components with the Uniglide system between 2006 and 2014. The primary outcome was patient reported outcome measure (PROM) using the Oxford Knee Score (OKS). Secondary outcomes were the American Knee Society Score (AKSS), the Western Ontario and McMaster University (WOMAC) arthritis index and the assessment of complications/reoperation.

Results

There were 163 primary UKAs. With a minimum 10-year follow-up there were 101 patients with PROM scores available (53 fixed vs 48 mobile); there was no statistically significant difference between the two groups (OKS 36.9 [11.2], n = 53 vs 36.8 [9], n = 48; p = 0.990). However, regarding the early revision by 10 years, there was a statistically significant lower chance in the fixed bearing group (risk ratio was found to be 0.42 [95 %CI 0.184 to 0.937; p = 0.030]).

Conclusions

This study shows comparable good clinical outcomes between fixed and mobile bearing UKA with a minimum of 10-year follow-up. However, higher revision rates were demonstrated in the mobile bearing group over the course of 10 years post-operatively.

背景：内侧单室膝关节置换术（UKA）的最佳承载面设计尚未确定。在这项来自单一机构的随机对照试验中，我们的目的是比较单一设计的股骨假体内侧UKA与来自相同（Corin AMC，后来更名为Uniglide）植入系统的固定或移动承重胫骨假体的临床结果、并发症和关节存活。方法：这是一项前瞻性随机试验，患者在2006年至2014年期间随机分配使用Uniglide系统的固定或活动胫骨组件。主要终点是使用牛津膝关节评分（OKS）的患者报告终点测量（PROM）。次要结果是美国膝关节协会评分（AKSS），西安大略省和麦克马斯特大学（WOMAC）关节炎指数和并发症/再手术评估。结果：原发性UKAs 163例。在至少10年的随访中，有101例患者获得PROM评分（53例固定对48例移动）；两组间差异无统计学意义（OKS 36.9 [11.2], n = 53 vs 36.8 [9], n = 48; p = 0.990）。然而，对于10年之前的修正，固定轴承组的风险比有统计学意义的低（风险比为0.42 [95% CI 0.184 ~ 0.937; p = 0.030]）。结论：该研究显示，至少10年随访后，固定和活动轴承UKA的临床结果相当良好。然而，在术后10年的过程中，活动轴承组的翻修率更高。

{"title":"Fixed versus mobile bearing medial unicompartmental knee arthroplasty with the same femoral implant design: a randomised controlled trial with a minimum of 10-year follow-up","authors":"Konstantinos Tsikopoulos , Konstantinos Kazamias , Paul White , James Robinson , John Newman , Andrew Porteous , James Murray","doi":"10.1016/j.knee.2025.104304","DOIUrl":"10.1016/j.knee.2025.104304","url":null,"abstract":"<div><h3>Background</h3><div>The optimal bearing surface design for medial unicompartmental knee arthroplasty (UKA) has yet to be determined. In this randomised controlled trial from a single institution, we aimed to compare the clinical outcome, complications and joint survival of a single design femoral component medial UKA with either a fixed or mobile bearing tibial component from the same (Corin AMC, later rebranded Uniglide) implant system.</div></div><div><h3>Methods</h3><div>This was a prospective randomised trial with patients randomised to either fixed or mobile tibial components with the Uniglide system between 2006 and 2014. The primary outcome was patient reported outcome measure (PROM) using the Oxford Knee Score (OKS). Secondary outcomes were the American Knee Society Score (AKSS), the Western Ontario and McMaster University (WOMAC) arthritis index and the assessment of complications/reoperation.</div></div><div><h3>Results</h3><div>There were 163 primary UKAs. With a minimum 10-year follow-up there were 101 patients with PROM scores available (53 fixed vs 48 mobile); there was no statistically significant difference between the two groups (OKS 36.9 [11.2], n = 53 vs 36.8 [9], n = 48; <em>p</em> = 0.990). However, regarding the early revision by 10 years, there was a statistically significant lower chance in the fixed bearing group (risk ratio was found to be 0.42 [95 %CI 0.184 to 0.937; <em>p</em> = 0.030]).</div></div><div><h3>Conclusions</h3><div>This study shows comparable good clinical outcomes between fixed and mobile bearing UKA with a minimum of 10-year follow-up. However, higher revision rates were demonstrated in the mobile bearing group over the course of 10 years post-operatively.</div></div>","PeriodicalId":56110,"journal":{"name":"Knee","volume":"59 ","pages":"Article 104304"},"PeriodicalIF":2.0,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145829100","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0