In Vivo Kinematic Analysis of Bicruciate-Retaining Total Knee Arthroplasty Focused on Function of the ACL

uncertain. In this study, we performed an in vivo kinematic analysis of squat motion on level ground and on a downward slope in patients treated with BCR-TKA to examine the value of anterior cruciate ligament (ACL) preservation.Methods: The subjects were ten valgus knees that underwent TKA (BCR: 5 knees, CR: 5 knees) at our hospital. We evaluated in vivo kinematics of the knee using fluoroscopy and investigated the femoral component translation relative to the tibial component from extension to maximum flexion, and the rotation angle between the components under the two conditions. Statistical analysis was conducted by Mann-Whitney U test to compare the rotational angle, the location of lateral and medial contact points per flexion angle. Differences in these parameters between the BCR and CR groups across the flexion angles were compared by repeated measures ANOVA. Results: Rotation of the femoral component to the tibial component occurred gradually as flexion continued. On level ground, lateral rotation at 0° to 120° flexion was 14.5±1.95° in the BCR group and 7.9±0.47° in the CR group. Medial translation was 4.1±1.73mm in the BCR group and 2.5±1.64mm in the CR group, and lateral translation was 13.2±1.6mm in the BCR group and 7.1±1.74mm in the CR group. On a forward slope, lateral rotation was 12.7±1.45° in the BCR group and 7.57±0.47° in the CR group. Medial translation was 5.87±1.78mm in the BCR and 2.9±0.81mm in the CR, and lateral translation was 13.6±1.84mm in the BCR and 7.4±0.96mm in the CR.Conclusion: An in vivo kinetics analysis of deep flexion motion was conducted on level ground and on a forward slope to stress the ACL. Under both conditions, kinetics close to screw home movement were found in the BCR group and rotation was significantly larger than that in the CR group. The medial contact point between components was located significantly more anterior in the BCR group. In conclusion, BCR-TKA was found to have in vivo kinetics close to those of a normal knee, in comparison with CR-TKA.

Bicruciate retaining total knee arthroplasty : results throughout history

Approximately 20% amongst patients are dissatisfied after total knee arthroplasty (TKA). Bicruciate retaining (BCR) TKA offers superior knee kinematics and proprioception, but many surgeons abandoned its use because of complications and technical difficulties. Recently, two new BCR implant designs were introduced : Vanguard XP (Zimmer Biomet) and Journey XR (Smith&Nephew). We searched Pubmed, Limo, Embase and Cochrane, screened reference lists of eligible studies and included studies that met the inclusion criteria. We included 35 articles reporting on ten different BCR implants, including three articles presenting results of the Vanguard XP prosthesis. Unfortunately, no articles reporting on the results of the Journey XR prosthesis had been published. The BCR implants of the early 1970s showed good functional results, but a high rate of complications, mainly loosening and infections. The Townley Anatomic TKA was the first BCR implant with good clinical results, a low incidence of loosening and a high survivorship. One article of the three reporting on the Vanguard XP yielded high patient satisfaction (94%) with two revisions (1.4%). The two other articles reported three revisions (5%) after one year of follow-up and 19 revisions (13.4%) after three years of follow-up. Throughout history, the functional results of BCR TKA improved, with lessening of the complications. The short-term results of the Vanguard XP implant showed good functional results, but two out of three articles reported a high rate of loosening. Based on the results reported in this review, the use of BCR TKA is still debatable. Further high-level evidence research is necessary to assess the clinical benefit of BCR TKA.

In vivo kinematics and cruciate ligament forces in bicruciate-retaining total knee arthroplasty

We analyzed the effects of bicruciate-retaining total knee arthroplasty (BCR-TKA) on knee kinematics and cruciate ligament forces. Patients (N = 15) with osteoarthritis (OA) and an intact anterior cruciate ligament (ACL) underwent magnetic resonance imaging and single-plane fluoroscopy to measure tibiofemoral kinematics during two deep knee bend activities before and after BCR-TKA: (1) weight-bearing squat; (2) non-weight-bearing cross-legged sitting. Forces in ligament bundles were calculated using VivoSim. The dynamic range of varus-valgus angulation decreased from 3.9 ± 4.4° preoperatively to 2.2 ± 2.7° postoperatively. Preoperatively, the medial femoral condyle translated anteriorly from 10° to 50° of flexion, and posteriorly beyond 50° of flexion. Postoperatively, the medial and lateral femoral condyles translated posteriorly throughout flexion in a medial pivot pattern. ACL forces were high in extension and decreased with flexion pre- and postoperatively. PCL forces increased with flexion preoperatively and did not change significantly postoperatively. Preoperatively, ACL forces correlated with anteroposterior translation of the femoral condyles. Postoperatively, PCL forces correlated with anteroposterior translation of the lateral femoral condyle. BCR-TKA altered knee kinematics during high flexion activity which correlated significantly with changes in cruciate ligament forces.

The Effect of Joint Line Elevation on In Vivo Knee Kinematics in Bicruciate Retaining Total Knee Arthroplasty

Prior studies have reported a negative effect on both clinical outcomes and patient-reported outcome measures (PROMS) following joint line elevation (JLE) in cruciate-retaining (CR) total knee arthroplasty (TKA) and posterior stabilized (PS) TKA designs. This experimental study was aimed to quantify the effect of JLE on in vivo knee kinematics in patients with bicruciate retaining (BCR) TKA during strenuous activities. Thirty unilateral BCR TKA patients were evaluated during single-leg deep lunge and sit-to-stand using a validated combined computer tomography and dual fluoroscopic imaging system. Correlation analysis was performed to quantify any correlations between JLE and in vivo kinematics, as well as PROMS. There was a significant negative correlation between JLE and maximum flexion angle during single-leg deep lunge (ρ = −0.34, p = 0.02), maximum varus joint angles during single-leg deep lunge (ρ = −0.37, p = 0.04), and sit-to-stand (ρ = −0.29, p = 0.05). There was a significant negative correlation between JLE and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score (ρ = −0.39, p = 0.01) and knee disability and osteoarthritis outcome score physical function (KOOS-PS; ρ = −0.33, p = 0.03). The JLE that yields a significant loss in PROMS and maximum flexion angles were 2.6 and 2.3 mm, respectively. There was a linear negative correlation of JLE with both in vivo knee kinematics and PROMS, with changes in JLE of greater than 2.6 and 2.3 mm, leading to a clinically significant loss in PROMS and maximum flexion angles, respectively, suggesting an increased need to improve surgical precision to optimize patient outcomes following BCR TKA.

In Vivo Kinematic Analysis of Bicruciate-retaining Total Knee Arthroplasty Focused on Function of the ACL

Background: The utility of a bi-cruciate retaining total knee arthroplasty (BCR-TKA) is uncertain. In this study, we performed an in vivo kinematic analysis of squat motion on level ground and on a downward slope in patients treated with BCR-TKA to examine the value of anterior cruciate ligament (ACL) preservation.Methods: The subjects were ten valgus knees that underwent TKA (BCR: 5 knees, CR: 5 knees) at our hospital. We evaluated in vivo kinematics of the knee using fluoroscopy and investigated the femoral component translation relative to the tibial component from extension to maximum flexion, and the rotation angle between the components under the two conditions. Statistical analysis was conducted by Mann-Whitney U test to compare the rotational angle, the location of lateral and medial contact points per flexion angle. Differences in these parameters between the BCR and CR groups across the flexion angles were compared by repeated measures ANOVA.Results: Rotation of the femoral component to the tibial component occurred gradually as flexion continued. On level ground, lateral rotation at 0° to 120° flexion was 14.5±1.95° in the BCR group and 7.9±0.47° in the CR group. Medial translation was 4.1±1.73mm in the BCR group and 2.5±1.64mm in the CR group, and lateral translation was 13.2±1.6mm in the BCR group and 7.1±1.74mm in the CR group. On a forward slope, lateral rotation was 12.7±1.45° in the BCR group and 7.57±0.47° in the CR group. Medial translation was 5.87±1.78mm in the BCR and 2.9±0.81mm in the CR, and lateral translation was 13.6±1.84mm in the BCR and 7.4±0.96mm in the CR.Conclusion: An in vivo kinetics analysis of deep flexion motion was conducted on level ground and on a forward slope to stress the ACL. Under both conditions, kinetics close to screw home movement were found in the BCR group and rotation was significantly larger than that in the CR group. The medial contact point between components was located significantly more anterior in the BCR group. In conclusion, BCR-TKA was found to have in vivo kinetics close to those of a normal knee, in comparison with CR-TKA.

Posterior Tibial Slope Increases Anterior Cruciate Ligament Stress in Bi-Cruciate Retaining Total Knee Arthroplasty: In Vivo Kinematic Analysis

The study design involved here is experimental in nature. The resection of the anterior cruciate ligament (ACL) during conventional total knee arthroplasty (TKA) has been considered a potential factor leading to abnormal in vivo knee kinematics. Bi-cruciate retaining (BCR) TKA designs allow the preservation of the ACL with the potential to restore native knee kinematics. This study aimed to investigate the effect of posterior tibial slope (PTS) on stress experienced by the ACL during weight bearing sit-to-stand (STS) and single-leg deep lunge. The ACL elongation patterns were measured in 30 unilateral BCR TKA patients during weight-bearing STS and single-leg deep lunge using a validated dual fluoroscopic tracking technique. The minimum normalized stress within the anteromedial (AM) and posterolateral (PL) bundle of the ACL during weight-bearing STS and single-leg deep lunge was found at a PTS of 3.7 degrees. The maximum AM and PL bundle stresses were observed at a PTS of 8.5 and 9.3 degrees, respectively during STS and at 8.4, and 9.1 degrees, respectively during single-leg deep lunge. There was a significant positive correlation between PTS and stress observed within the AM and PL bundle of the ACL during weight-bearing STS (R 2 = 0.37; p < 0.01; R2 = 0.36; p = 0.01) and single-leg deep lunge (R 2 = 0.42; p < 0.01; R 2 = 0.40; p < 0.01). The study demonstrates that PTS of operated BCR TKA knees has a significant impact on the stress experienced by the preserved ACL during weight-bearing STS and single-leg deep lunge. This suggests that avoiding excessive PTS may be one of the surgical implant alignment factors to consider during surgery to minimize increased loading of the preserved ACL.

In vivo kinematics of deep lunges and sit-to-stand activities in patients with bicruciate-retaining total knee arthroplasty

Aims The removal of the cruciate ligaments in total knee arthroplasty (TKA) has been suggested as a potential contributing factor to patient dissatisfaction, due to alteration of the in vivo biomechanics of the knee. Bicruciate retaining (BCR) TKA allows the preservation of the cruciate ligaments, thus offering the potential to reproduce healthy kinematics. The aim of this study was to compare in vivo kinematics between the operated and contralateral knee in patients who have undergone TKA with a contemporary BCR design. Methods A total of 29 patients who underwent unilateral BCR TKA were evaluated during single-leg deep lunges and sit-to-stand tests using a validated computer tomography and fluoroscopic imaging system. In vivo six-degrees of freedom (6DOF) kinematics were compared between the BCR TKA and the contralateral knee. Results During single-leg deep lunge, BCR TKAs showed significantly less mean posterior femoral translation (13 mm; standard deviation (SD) 4) during terminal flexion, compared with the contralateral knee (16.6 mm, SD 3.7; p = 0.001). Similarly, BCR TKAs showed significantly less mean femoral rollback (11.6 mm (SD 4.5) vs 14.4 mm (SD 4.6); p < 0.043) during sit-to-stand. BCR TKAs showed significantly reduced internal rotation during many parts of the strenuous flexion activities particularly during high-flexion lunge (4° (SD 5.6°) vs 6.5° (SD 6.1°); p = 0.051) and during sit-to-stand (4.5° (SD 6°) vs 6.9° (SD 6.3°); p = 0.048). Conclusion The contemporary design of BCR TKA showed asymmetrical flexion-extension and internal-external rotation, suggesting that the kinematics are not entirely reproduced during strenuous activities. Future studies are required to establish the importance of patient factors, component orientation and design, in optimizing kinematics in patients who undergo BCR TKA. Cite this article: Bone Joint J 2020;102-B(6 Supple A):59–65.

In Vivo Kinematics of Bicruciate-Retaining Total Knee Arthroplasty with Anatomical Articular Surface under High-Flexion Conditions

Bicruciate-retaining total knee arthroplasty (BCR-TKA) recreates normal knee movement by preserving the anterior cruciate and posterior cruciate ligaments. However, in vivo kinematics of BCR-TKA with the anatomical articular surface remains unknown. The objective of this study was to evaluate in vivo kinematics of BCR-TKA with the anatomical articular surface during high-flexion activities. For this purpose, 17 knees after BCR-TKA with an anatomical articular surface were examined. Under fluoroscopy, each patient performed squatting and cross-legged sitting motions. To estimate the spatial position and orientation of the knee, a two-dimensional or three-dimensional registration technique was used. Rotation, varus-valgus angle, and anteroposterior translation of medial and lateral contact points of the femoral component relative to the tibial component were evaluated in each flexion angle. The results showed that from 80 to 110° of flexion, the femoral external rotation during squatting was significantly larger than that during cross-legged sitting. At maximum flexion, the knees during sitting indicated significantly more varus alignment than during squatting. During squatting, a medial pivot pattern was observed from minimum flexion to 10° flexion, with no significant movement beyond 10° of flexion. Conversely, during cross-legged sitting, no significant movement was detected from minimum flexion to 60° of flexion, with a medial pivot beyond 60° of flexion. Therefore, the knees showed relatively normal kinematics after BCR-TKA with an anatomical articular surface; however, it varied during high-flexion activities depending on the activity.

Does Component Alignment Affect Patient Reported Outcomes following Bicruciate Retaining Total Knee Arthroplasty? An In Vivo Three-Dimensional Analysis

This is an experimental study. Anterior cruciate ligament (ACL) and posterior cruciate ligament (PCL) retaining bicruciate retaining (BCR) total knee arthroplasty (TKA) have the potential to restore normal knee kinematics and thus improve patient outcome. Limited studies have examined the relationship between component alignment and patient-reported outcome measures (PROM). This study aims to determine (1) accurate three-dimensional (3D) component alignment of BCR TKA and (2) whether the component alignment of BCR TKA affects PROMs. The 3D modeling analysis was performed based on computed tomography images from 29 BCR TKAs. Component orientations were quantified for femoral and tibial components in the sagittal, axial, and coronal planes. The knee society scores (KSS) were collected preoperatively and postoperatively at 1-year follow-up. Multiple comparisons were performed to analyze the relationship between component alignment and patient outcomes. High variability was observed in the tibial component alignment (root–mean-square values: axial plane 6.6 degrees, sagittal plane 5.1 degrees, and coronal plane 4.0 degrees). At 1-year follow-up, significant improvement in KSS was noted in BCR TKA patients (p < 0.001). However, regression analysis adjusting for baseline KSS demonstrated the postoperative KSS was negatively associated with the posterior tibial slope (B [slope of the output of the regression analysis] = 2.597, p = 0.006). Patients with greater posterior tibial slopes were reported poorer postoperative functions at 1-year follow-up. Excessive posterior tibial slope may generate greater posterior force on the femur that leads to continuous overloading of the preserved ACL, suggesting optimal sagittal plane alignment of the tibial component may be important for the optimization of postoperative functions of BCR TKA patients.

Gender Influences Gait Asymmetry following Bicruciate-Retaining Total Knee Arthroplasty

This is an experimental study. Gender has been reported to influence outcomes in patients with total knee arthroplasty (TKA) for knee osteoarthritis (OA). However, the influence of gender on three-dimensional (3D) in vivo kinematics during gait remains unclear. This study aimed to determine if 3D gait kinematics, including 3D knee translations and rotations, differed in men and women following bicruciate-retaining (BCR) TKA. Twenty-nine well-functioning unilateral BCR TKA patients (14 males and 15 females) underwent evaluation of both knees during level walking on a treadmill at a self-selected speed using a dual fluoroscopic imaging system. Interlimb comparisons of in vivo 6 degree-of-freedom kinematics were compared between male and female patients. Differences of pre- and postoperative Knee Society scores (KSSs) were compared between the groups. Both groups were matched regarding age and body mass index. Both male and female patients demonstrated improvement in their postoperative KSSs. Statistically significant differences were observed with respect to spatiotemporal anterior–posterior interlimb translations (p < 0.05). Although females presented more femoral posterior translation in the operative knee than the nonoperative knee during most of the stance phases (2.8 vs. −1.6 mm), males exhibited less femoral translation in the operative knee than the nonoperative knee (2.3 vs. −1.8 mm), when interlimb differences were detected during stance phase. Results demonstrated that there are 3D motion asymmetries of the knee in both male and female unilateral BCR TKA patients during gait with anterior–posterior interlimb asymmetries significantly greater in female than male participants. This suggests that gender may influence the in vivo knee kinematics in BCR TKA patients during gait.