Robotic‐assisted total knee arthroplasty (RTKA) has gained widespread acceptance due to its demonstrated ability to improve surgical accuracy compared to conventional total knee arthroplasty (CTKA). While the precise impact of RTKA on postoperative patient‐reported outcome measures (PROMs) remains inconclusive, the increased accuracy in alignment and joint kinematics suggests potential improvements in patient satisfaction and functional outcomes. Two primary RTKA systems exist: image‐based, which uses preoperative CT scans for detailed 3D modeling, and image‐less, which relies on intra‐operative digitization of anatomical landmarks. Both systems aim to achieve accurate implant placement and soft‐tissue balancing, yet they differ in methodology and reliance on preoperative data.Despite RTKA's theoretical advantages, there is ongoing debate about whether accuracy alone is sufficient to achieve optimal postoperative outcomes, particularly concerning joint kinematics and alignment strategies. Literature reveals no significant difference in coronal plane alignment between image‐based and image‐less systems, though image‐less systems may be more prone to varus errors due to the reliance on intra‐articular landmarks. Additionally, image‐free systems may face challenges in replicating native knee anatomy, especially in the sagittal plane, leading to potential limitations in achieving ideal tibial slope reconstruction.The future of RTKA may lie in refining implant positioning strategies that minimize postoperative alterations to pre‐arthritic knee kinematics, particularly with standardized off‐the‐shelf implants. As robotic technology evolves, there is potential to enhance surgical outcomes by combining accuracy with personalized alignment approaches that better address individual patient anatomy. Further research is needed to assess the long‐term clinical benefits of RTKA and its capacity to improve patient‐specific functional outcomes.Level of evidence: level 5

In order to successfully implement individualized patient rehabilitation and home-based rehabilitation programs, the rehabilitation process should be objectifiable, monitorable and comprehensible. For this purpose, objective measurements are required in addition to subjective measurement tools. Thus, the aim of this prospective, single-center clinical trial is the clinical validation of an objective, digital medical device (DMD) during the rehabilitation after anterior cruciate ligament reconstruction (ACLR) with regards to an internationally accepted measurement tool. Sixty-seven patients planned for primary ACLR (70:30% male–female, aged 25 years [21–32], IKDC-SKF 47 [31–60], Tegner Activity Scale 6 [4–7], Lysholm Score 57 [42–72]) were included and received physical therapy and the DMD after surgery. For clinical validation, combined measures of range of motion (ROM), coordination, strength and agility were assessed using the DMD in addition to patient-reported outcome measures (PROMs) at three and six months after ACLR. Significant correlations were detected for ROM (rs = 0.36–0.46, p < 0.025) and strength/agility via the single-leg vertical jump (rs = 0.43, p = 0.011) and side hop test (rs = 0.37, p = 0.042), as well as for coordination via the Y-Balance test (rs = 0.58, p ≤ 0.0001) regarding the IKDC-SKF at three months. Additionally, DMD test results for coordination, strength and agility (Y-Balance test (rs = 0.50, p = 0.008), side hop test (rs = 0.54, p = 0.004) and single-leg vertical jump (rs = 0.44, p = 0.018)) correlate significantly with the IKDC-SKF at six months. No adverse events related to the use of the sensor-based application were reported. These findings confirm the clinical validity of a DMD to objectively quantify knee joint function for the first time. This will have further implications for clinical and therapeutic decision making, quality control and monitoring of rehabilitation measures as well as scientific research.

Background: Robotic-assisted unicompartmental arthroplasty (rUKA) is gradually gaining more popularity than its conventional counterpart (cUKA). Current studies are highly heterogenic in terms of methodology and the reported results; therefore, establishing the optimal recommendation for patients becomes less straightforward. For this reason, this meta-analysis aims to provide an up-to-date evidence-based analysis on current evidence regarding clinical outcomes and complication rates following rUKA and cUKA. Methods: A meta-analysis was conducted following PRISMA guidelines. Five databases were searched, PubMed via MEDLINE, Epistemonikos, Cochrane Library, Web of Science, and Scopus. The relevant inclusion criteria were as follows: comparative clinical studies in which medial rUKA was compared to medial cUKA (prospective or retrospective designs), (2) human studies, (3) meta-analyses for cross-referencing, and (4) English language. The relevant extracted data were patient demographics, patient-reported outcome measures (PROMs), range of motion, and complications. A random-effects meta-analysis and subgroup analysis were conducted. The results include mean differences (MDs) and odds ratios (ORs), along with 95% confidence intervals (CIs) for continuous and binary variables, respectively. Results: rUKA showed a higher overall FJS-12 score compared to cUKA, with MD = 6.02 (95%CI: −0.07 to 12.1), p = 0.05. At 6 months postoperatively, the MD increased to 10.31 (95%CI: 5.14 to 15.49), p < 0.01. At a minimum 36-month follow-up, cUKA had a higher all-cause revision rate, with OR = 3.31 (95%CI: 1.25 to 8.8), p = 0.02, and at a minimum 60-month follow-up, a higher aseptic loosening rate, with OR = 3.86 (95%CI: 1.51 to 9.91), p < 0.01, compared to rUKA. Conclusions: rUKA provides better FJS-12 results compared to cUKA, as well as lower all-cause revision and aseptic loosening rates at 36- and 60-month follow-up, respectively. However, long-term follow-up is still pending.

Background: Information derived from functional return-to-sport (RTS) tests after primary anterior cruciate ligament (ACL) reconstruction (ACLR) can have a significant impact on the risk reduction of ACL reruptures. However, due to space, time, and financial limitations, few clinicians utilize objective data to assess their patients’ functional abilities after ACLR. Purpose: To identify validated and feasible RTS tests that could reliably estimate the risk of reinjury after ACLR in everyday clinical practice beyond the highly sophisticated laboratory setting. Study Design: Systematic review; Level of evidence, 4. Methods: A focused review was performed by experts of the committees for Ligament Injuries and Prevention/Rehabilitation of the German Knee Society. RTS functional tests, their reinjury prognostic values (if known), their reliabilities, and their implementation capacities were extracted from the original studies on the described RTS test setup, as well as from studies on potential test alternatives. These alternatives were required to be less resource-consuming yet still validated and thus able to be implemented into everyday practice. All tests were categorized according to their relevant target objective: isokinetic or isometric strength, functional (hopping and jumping) ability, or self-reported readiness. Results: In the final analysis, 19 studies involving 7513 patients were included. From these, a total of 21 RTS tests were retrieved, and 13 tests were included. For strength testing, 2 dynamic tests and 1 static test were found to be eligible. Functional ability was represented by 8 different jump, hop, and agility tests. Tests for self-reported readiness included the ACL–Return to Sport after Injury scale and the Knee injury and Osteoarthritis Outcome Score Sport and Recreation subscore. Alternative tests included the 8–repetition maximum test, handheld/portable dynamometer, single-leg vertical (countermovement) hop with inertial sensor or smartphone app, and the drop jump with knee displacement or normalized knee distance measurement. Conclusion: For most of the strength and functional abilities assessed by RTS tests, validated and less resource-consuming alternatives do exist. Therapists and clinicians working in nonlaboratory settings may find it helpful to select from a menu of established RTS tests and test alternatives for each relevant target objective, depending on their individual requirements.

The aim of this study was to establish a consensus-based classification of postoperative events following anterior cruciate ligament reconstruction (ACLR), clearly distinguishing no complication/normal clinical course, minor complication, major complication, and failure, using a structured Delphi methodology among international experts in anterior cruciate ligament (ACL) surgery. A three-round modified Delphi process was conducted involving international high-volume ACL surgeons. An initial set of statements addressing potential postoperative events after ACLR was developed by a working group based on clinical expertise and contemporary literature. Panelists classified each statement as no complication/normal clinical course, minor complication, major complication, or failure. Consensus was predefined as ≥75% agreement within a single category. Statements reaching consensus were retained, whereas non-consensus statements were revised and re-evaluated in subsequent rounds. Thirty-nine experts completed the first and second Delphi rounds, and 30 (76.9%) completed the third round. The initial 52 statements were expanded to 67 in round two and refined to 46 in round three. Consensus was achieved for 14 statements (26.9%) in round one, 21 statements (31.3%) in round two, and 20 statements (43.5%) in round three. Overall, consensus was reached for 55 statements, forming the final classification framework. The panel clearly distinguished graft failure-defined as graft insufficiency or symptomatic instability-from major complications requiring surgical intervention or associated with substantial morbidity, and from minor complications or expected postoperative findings. Notably, traumatic graft rupture following a clearly documented new injury was not considered a postoperative complication. This international Delphi consensus establishes a standardized and clinically meaningful classification of postoperative events following ACLR. By clearly distinguishing no complication, minor complication, major complication, and failure, this framework provides a shared language that may improve consistency in outcome reporting, facilitate comparison across studies, and enhance the interpretability of clinical research and registry data. V, expert consensus.