Explore the vast range of titles available.

Purpose To assess measurement equivalence, inter- and intra-rater reliability, standard error of measurements (SEM) and false positive measurements (FPM) of four different knee arthrometers (KLT,Karl Storz; KiRA, I + ; KT-1000 MEDmetric Corp; Rolimeter, Aircast) in healthy patients. Methods Four different investigators (two advanced (AR) and two beginners (BR)) examined 12 participants with healthy knees at two time points with regards to anterior tibial translation (ATT) and side-to-side difference (SSD). Test equivalence was assessed using the TOST (two-one-sided t test) procedure with ± 1 mm equivalence boundaries. Intraclass correlation coefficients (ICCs) were calculated using two-way mixed effects models. Furthermore, false positive-(SSD > 3 mm) and SEMs were assessed. Results A total of 2304 Lachman Tests were performed. Between-rater SSDs were equivalent between AR and BR raters for the Rolimeter only. Inter-rater ICC values (SSD, ATT) were graded as “poor” to “moderate” for all devices. Equivalent test–retest results were observed for all raters using the Rolimeter, KLT and KT-1000, whereas measurement consistency with KiRA was given in the advanced examiners group only. Intra-rater ICC values (Range: SSD, ATT) were graded as “poor” to “moderate” for SSD values and “moderate” to “good” for ATT. SEMs were lowest for the Rolimeter and highest for KiRA. FPM were never obtained with the Rolimeter (0%), twice (2.1%) with the KT-1000, three times (3.1%) with the KLT and 33 times (34.4%) using KiRA. Conclusion There is acceptable intra-rater but poor inter-rater reliability with all tested arthrometers. Measures of knee laxity are comparable between Rolimeter, KLT and KT-1000 but higher for KiRA. Clinically, the present study shows that repeated arthrometry measurements should always be performed by the same investigators.

Purpose Bilateral involvement is common in patients with patellar instability. The management of bilateral patellar instability is associated with increased complication rate. The higher complication rate in this cohort may be related to the presence of underlying anatomic risk factors. The purpose of the study was to evaluate the presence and side-to-side differences in risk factors between knees in bilateral patellar instability. Methods In a retrospective study (2008–2017), demographic information, characteristics of patellar dislocation and anatomic risk factors on MRI (trochlear dysplasia, patellar height, tibial tubercle lateralization, patellar tilt, sulcus angle, bump height) were evaluated in both knees of all patients ( n  = 32, 15 males and 17 females) with bilateral patellar instability. The risk factors were analyzed based on established cut off values and were compared between gender, laterality and more symptomatic (index) knee. Knee symmetry and absolute differences between risk factors for both knees were analyzed. Results The mean age of 32 patients was 14.6 ± 2.3 years. Of the 4 major anatomic risk factors, the most common were trochlear dysplasia in 59/64 (92.1%) knees and patella alta in 51/64 (79.7%) knees. Tibial tubercle lateralization was the least common risk factor being present in 8/64 (12.5%) knees. Of 64 knees, 55 (85.9%) had 2 or more risk factors and 30 (46.8%) had 3 or all 4 risk factors present. There were no significant differences in risk factors based on gender, laterality or index knee. There was symmetry between paired knees for 31/32 (96.8%) patients for trochlear depth, 29/32 (90.6%) for patellar tilt, 27/32 (84.3%) for TT–TG distance and 25/32 (78.1%) for patellar height. There were no significant differences in absolute measurements between knees for any of the risk factors. Conclusion Patients with bilateral instability had multiple risk factors, with trochlear dysplasia being the most common and increased TT–TG distance being the least common. Majority of patients had 2 or more risk factors and about half had 3 or 4 risk factors in each knee. There was symmetry between paired knees for each risk factor without any significant differences between the index knee compared to the contralateral knee. Level of evidence Level III.

Background As a recently available arthrometer, the Ligs arthrometer has been gradually used in clinical practice to assess knee stability. However, its reliability has not been fully established in this regard. The aim of this study was to assess the intra-rater and inter-rater reliability of the Ligs arthrometer for measuring anterior tibial translation (ATT) and the corresponding side-to-side difference (SSD) in healthy subjects. Methods A total of 40 healthy male subjects were recruited for this study between June 2023 and September 2023. Three examiners with different levels of experience tested the subjects with the Ligs arthrometer for ATT and SSD measurements. ATT values for both knees and the corresponding SSD at 90 N, 120 N, and 150 N were recorded for analysis. Statistical significance was determined using Student’s t test or one-way analysis of variance (ANOVA). The intraclass correlation coefficient (ICC) was used to assess the intra-rater and inter-rater reliability of the Ligs arthrometer for ATT and SSD measurements. Results No subject asked to stop any test due to pain or discomfort. There was no significant difference among the three examiners in ATT measurements of the subjects’ ipsilateral knees and SSD measurements at the same load ( P  > 0.05 for all). Furthermore, ATT measurements for the subjects’ left and right knees measured by the same examiner were comparable ( P  > 0.05 for all). The Ligs arthrometer showed excellent intra-rater reliability (ICCs = 0.930–0.982) for ATT measurements and moderate to good intra-rater reliability (ICCs = 0.705–0.862) for SSD measurements. Similarly, its inter-rater reliability was excellent (ICCs = 0.911–0.930) for ATT measurements, but moderate (ICCs = 0.684–0.737) for SSD measurements. Conclusion The Ligs arthrometer had moderate to excellent intra-rater and inter-rater reliability for ATT and SSD measurements in healthy knees. As compared with ATT measurements, SSD measurements showed lower intra-rater and inter-rater reliability at the same load. It is recommended that the tests be performed by the same examiner when using the Ligs arthrometer for SSD measurements.

Background Non-contact injuries such as anterior cruciate ligament ruptures often occur during physical load toward the end of a match. This is ascribed to emerging processes due to exercise-induced fatigue. Moreover, non-contact injuries often occur during dynamic actions such as landing or cutting movements. Inter-limb asymmetries are suggested as one possible cause for those injuries based on findings indicating that asymmetries between limbs are associated with a higher injury risk. Hence, assessing inter-limb asymmetry during physical load in the condition of exercise-induced fatigue is warranted to identify potentially relevant precursors for non-contact injuries. Objective The objective of this study was to overview the current state of evidence concerning the influence of exercise-induced fatigue on inter-limb asymmetries through a systematic review. Methods A systematic literature search was conducted using the databases Web of Science, Scopus, PubMed, SURF, and SPONET to identify studies that assessed inter-limb asymmetries of healthy people, calculated with an asymmetry equation, before and after, or during a loading protocol. Results Thirteen studies were included in the systematic review. The loading protocols involved running, race walking, jumping, squatting, soccer, rowing, and combinations of different exercises. Moreover, different tasks/procedures were used to assess inter-limb asymmetries, e.g., squats, single-leg countermovement jumps, gait analysis, or isokinetic strength testing. The results seem to depend on the implemented loading protocol, the tasks/procedures, and the measured parameters. Conclusions Future research needs more systematization and consistency, assessing the effect of exercise-induced fatigue on inter-limb asymmetries. Moreover, the emergence of inter-limb asymmetries should be regarded in the context of sport-specific movements/tasks. Testing before, after, and during a physical loading protocol is advisable to consider the influence of exercise-induced fatigue on sport-specific tasks and to identify the possible mechanisms underlying load-dependent inter-limb asymmetries with regard to risk of non-contact injury.

Physical examination of the knee joint is used to diagnose the type and severity of knee ligament injury; however, these exams are qualitative and subjective. To perform common physical examinations, we developed an arthrometer which quantitatively measures the load–displacement response in anterior-posterior (AP) translation, internal-external rotation (IER) and varus-valgus (VV) rotation. Here we describe safety, reliability, minimum detectable changes (MDCs), and absolute side-to-side differences in twenty young, healthy subjects (ten male, ten female, mean age: 28 ± 6 years). The arthrometer consists of an instrumented mechanical linkage, a force-moment sensor, and software for real-time visualization and recording of the load–displacement responses. During testing, the subject sits reclined in a chair with their knee fixed at 30° of flexion. Two examiners tested both knees of each subject twice to assess reliability via intraclass correlation coefficients (ICC). All subjects completed the test protocol with minimal pain and stated that they would volunteer to be tested again. Each knee required on average five minutes to test. All intra-test reliabilities were excellent (≥0.91). Intra-examiner reliabilities ranged from good to excellent (0.62–0.89), and inter-examiner reliabilities were good to excellent (≥0.72). MDCs for repeat measures were ≤ 4.5 mm, 4.6°, and 2.3° for AP, IER, and VV, respectively. The absolute side-to-side differences for this cohort averaged 3.8 mm in AP, 5.5° in IER, and 2.2° in VV. Our arthrometer was safe, testing was time-efficient, and MDCs in our cohort of healthy subjects support utilization of this device for clinical research.

Background: The kneeling stress radiograph is valuable for quantifying posterior cruciate ligament (PCL) injuries. However, this method presents drawbacks, including patient discomfort during filming, radiation exposure, variability attributable to patient cooperation, and technician skill requirements. The modified Lachmeter technique offers an alternative approach. Its notable advantages are reproducibility, less patient pain or discomfort, and reduction of radiographic exposure. Purpose: To compare and find the correlation of the side-to-side difference (SSD) value between the modified Lachmeter technique and the kneeling stress radiograph. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: A total of 33 patients with isolated PCL injury were measured for the SSD value using a modified Lachmeter technique and a kneeling stress radiograph. Demographic data and SSDs were collected from each method and analyzed. Results: The sample entailed 26 men and 7 women, with a mean of 37.58 years (range, 15-65 years). There were 14 patients with right knee injuries and 19 patients with left knee injuries. The mean difference in absolute values between the 2 methods was 2.32 ± 2.29 mm. Interobserver and intraobserver intraclass correlation coefficients of the modified Lachmeter showed almost perfect agreement (0.909 and 0.977, respectively). Conclusion: The SSD showed an excellent correlation between the modified Lachmeter technique and kneeling stress radiographs. Consequently, the modified Lachmeter technique holds promise as an alternative to stress radiography for patients with isolated PCL injuries.

Background Inter-limb asymmetry is commonly regarded as a potential limitation for athletic performance and a contributor to injury risk. However, the influence of training status and sex on asymmetry in judokas remains poorly understood. Therefore, this study aimed to: (1) quantify inter-limb asymmetry in lean mass, bone mineral density, bone mineral content, and fat mass, and (2) examine how inter-limb morphological asymmetry varies across competitive levels (national vs. European) and sexes among young competitive judokas. Methods Lean mass, bone mineral density, bone mineral content, and fat mass were assessed using Dual-energy X-ray Absorptiometry in 27 male and 21 female competitive judokas aged 13–17 years. Comparisons between limbs were performed using paired-samples t-tests. Differences in asymmetry across competitive levels (national vs. European) and sexes were analyzed using Mann-Whitney U tests. Results Inter-limb asymmetry magnitudes ranged from 1.47% to 8.24% across groups. Overall, judokas showed greater values in the dominant limb compared to the non-dominant limb for most measures ( p  ≤ 0. 010). Mann-Whitney U tests identified significant differences in asymmetry between competitive levels only in lower-limb fat mass for both males ( p  = 0.015) and females ( p  = 0.033), and in lower-limb bone mineral content for females ( p  = 0.039). No significant differences in asymmetry were observed between sexes. Conclusion While inter-limb differences were present, the magnitude of asymmetry was generally small (≤ 8%) and did not differ significantly between competitive levels or sexes. These findings suggest that reducing morphological asymmetry in judokas may not be a priority, regardless of competition level or sex.

Purpose To compare clinical and radiological outcomes and failure rates between anatomical and high femoral tunnels in remnant-preserving single-bundle posterior cruciate ligament (PCL) reconstruction. Methods 63 patients who underwent remnant-preserving single-bundle PCL reconstruction between 2011 and 2018 with a minimum 2-year follow-up were retrospectively reviewed. Patients were divided into two groups according to the femoral tunnel position: group A (33 patients with anatomical femoral tunnel) and group H (30 patients with high femoral tunnels). The femoral tunnel was positioned at the center (group A) or upper margin (group H) of the remnant anterolateral bundle. The position of the femoral tunnel was evaluated using the grid method on three-dimensional computed tomography. Clinical and radiological outcomes and failure rates were compared between the groups at the 2-year follow-up. Results The position of the femoral tunnel was significantly high in group H than in group A (87.4% ± 4.2% versus 76.1% ± 3.7%, p  < 0.001). Clinical outcomes were not significantly different between the two groups in terms of the clinical scores (International Knee Documentation Committee subjective, Lysholm, and Tegner activity scores), range of motion, and posterior drawer test. Radiological outcomes also showed no intergroup differences in the side-to-side differences of posterior tibial translation and osteoarthritis progression. Side-to-side difference on the Telos stress radiograph was 5.2 ± 2.9 mm in group A and 5.2 ± 2.7 mm in group H (n.s.). There were four failures in group A (12.1%) and one in group H (3.3%). The differences between the groups were not statistically significant. Conclusion The clinical and radiological outcomes and failure rates of the high femoral tunnels were comparable with those of the anatomical femoral tunnels at the 2-year follow-up after remnant-preserving single-bundle PCL reconstruction. The findings of this study suggest that high femoral tunnels can be considered an alternative in remnant-preserving single-bundle PCL reconstruction. Level of evidence III.

Background: InternalBrace-augmented anterior cruciate ligament repair (ACL-IB) is believed to restore natural knee mechanics. However, there is a dearth of data on in vivo leg biomechanics after ACL-IB and comparability with gold standard surgery. Purposes: To (1) investigate differences in sagittal and frontal landing biomechanics of the legs in patients after ACL-IB (Comparison I) and after anterior cruciate ligament reconstruction (ACLR; Comparison II), compare the involved legs with controls (Comparison III), and (2) identify leg differences that were greater than those typically observed in controls. Study Design: Cross-sectional study, Level of Evidence 3. Methods: A total of 29 patients who had ACL-IB, 27 sex- and age-matched patients who had ACLR, and 29 matched controls were asked to perform single-leg hops (SLH) for maximum forward distance 2 years postoperatively, assessed by marker-based motion analysis. Sagittal (hip, knee, and ankle) and frontal (hip and knee) plane angles and peak moments, joint work contribution, and peak vertical ground-reaction force and loading rates during landing were calculated. Differences between the involved and uninvolved legs in patients (paired t tests) and between the involved legs in patients and the nondominant legs in controls (1-way analysis of variance) were analyzed. To determine whether these differences exceeded the typical variation seen in the control legs, we compared the overlap of the 95% CIs of the differences with the 95% CIs of the within-control differences (the nondominant versus dominant leg). Results: Patients who underwent ACL-IB (ACL-IB group) and ACLR (ACLR group) showed significant differences in their legs’ SLH landing biomechanics. Only leg differences in the ACL-IB group were greater than those in in the control group (no overlap): smaller peak knee flexion angle (leg difference: −8.3° [95% CI, −13 to −3.7]; d = −0.85; P = .001; controls [95% CI, −1.7 to 4.2]) and lower peak knee flexion moment (−0.60 Nm/kg [95% CI, −0.72 to −0.31]; d = −0.72; P < .001; controls [95% CI, −0.06 to 0.35]) in the involved compared with the uninvolved leg; and lower peak knee flexion moment in the involved leg compared with control legs (−0.50 Nm/kg [95% CI, −1 to −0.07]; d = −0.71; P = .020). Conclusion: Persistent differences in SLH landing biomechanics 2 years after ACL surgery suggest that ACL ruptures cause alterations that cannot be restored by augmented repair or reconstruction alone. The greater differences between the legs in the ACL-IB group than those typically seen within controls highlight the need for further research to understand the full potential or limitation of ACL preservation techniques.

Background: The relationship between remaining anterior knee laxity and poorer clinical outcomes after anterior cruciate ligament reconstruction (ACLR) may be underrated, and the criteria for failure of revision ACLR have not been defined. Purpose/Hypothesis: To evaluate a possible association between remaining knee laxity and functional scores in patients after revision ACLR. We hypothesized that a postoperative side-to-side-difference (SSD) in knee laxity of ≥6 mm will be an objective parameter for failure. Study Design: Cohort study; Level of evidence, 3. Methods: A total of 200 patients (77 women and 123 men; mean age, 30.8 ± 11 years; range, 18-61 years) who underwent revision ACLR between 2016 and 2019 were evaluated; The mean follow-up period was 30.2 ± 9 months (range, 24-67 months). Patients were divided into 3 groups according to postoperative SSD (<3 mm, 3-5 mm, or ≥6 mm). Preoperative and postoperative outcome measures (Lachman, pivot shift, visual analog scale [VAS] for pain, Tegner, Lysholm, International Knee Documentation Committee, and Knee injury and Osteoarthritis Outcome Score) were compared between the groups. Results: Of the 200 patients, 74% (n = 148) had a postoperative SSD of <3 mm at the latest follow-up, 19.5% (n = 39) had a postoperative SSD of 3 to 5 mm, and 6.5% (n = 13) had a postoperative SSD of ≥6 mm. Patients in all groups saw significant pre- to postoperative reductions in positive Lachman and pivot-shift tests as well as significant improvements in VAS pain, Lysholm, and Tegner scores (P < .001 for all). All postoperative functional scores of the patients with SSDs of <3 mm and 3-5 mm were significantly increased compared with those of patients with an SSD of ≥6 mm (P≤ .01 for all). Conclusion: In patients following revision ACLR, anterior and rotational knee laxity were successfully reduced while increasing postoperative functional outcomes. A remaining postoperative SSD of ≥6 mm was associated with inferior patient outcomes compared with an SSD <6 mm. An SSD of ≥6 mm represents an objective parameter in the definition of failure of revision ACLR.