Insert conformity variation affects kinematics and wear performance of total knee replacements

Survivorship and Patient Outcomes of Conforming Bearings in Modern Primary Total Knee Arthroplasty: Mean 3.5 Year Follow-Up

BACKGROUND

The use of conforming and congruent bearings in total knee arthroplasty (TKA) have rapidly increased due to the benefits of increased stability and the potential for replicating normal knee kinematics. However, limited data exist for these newly available bearings. This study evaluated revision-free survivorship and patient-reported outcome measures (PROMs) of a large granular database of primary TKAs using a single conforming bearing design.

METHODS

A total of 1,306 consecutive primary TKAs performed using a single conforming bearing design (85% cemented and 15% cementless) were retrospectively reviewed. Kaplan-Meier survivorship estimates were calculated based on the latest clinical follow-up. The PROMs and minimal clinically important differences were evaluated. A total of 93% of cases achieved minimum 1-year clinical follow-up (mean 3.5 years; range, 1 to 7), with a subset of 261 cases that achieved minimum 5-year follow-up (mean 5.8 years; range, 5 to 7).

RESULTS

All-cause and aseptic Kaplan-Meier survivorship estimates were 97.6 (95% CI [confidence interval], 97 to 99) and 98.1% (95% CI, 97 to 99) at 7.0 years. Revision-free survivorship did not differ by cemented or cementless fixation (98 versus 97%, P = .163). All PROM scores significantly improved from preoperative baseline (P < .001), and ≥ 86% of patients achieved minimal clinically important differences for Knee Society pain and Knee Injury and Osteoarthritis Outcome Score for Joint Replacement total scores. A total of 89% of cases reported their knees to 'sometimes or always' feel normal. For cases with minimum 5-year PROMs, 93% were 'very satisfied' or 'satisfied.'

CONCLUSIONS

Conforming-bearing TKA demonstrated excellent survivorship up to 7.0 years. In addition, PROMs were comparable to other designs reported in the literature. While mid-term (mean 3.5-year) results are promising, long-term data are warranted on survivorship due to potential polyethylene wear in conforming bearings with more surface area in contact with articulating surfaces.

LEVEL OF EVIDENCE

IV.

Alterations in articular cartilage frictional properties in the setting of acute gouty arthritis

The tribological behaviour of articular cartilage plays a key role in joint motion; however, there is a gap in research on the effect of hyperuricemic joint fluid on cartilage friction behaviour in acute gouty arthritis. In this study, we carried out a fixed-load scratch experiment to compare the friction and wear of articular cartilage under the lubrication of gouty arthritis arthritic fluid and normal human arthritic fluid, and the results showed that the cartilage friction coefficient of patients with acute gouty arthritis was significantly larger than that of normal human beings, and that the cartilage friction coefficient decreased with the elevation of normal load and sliding speed, and the change with the sliding speed varied more differently from that of normal human beings, and that the cartilage surface wear was more severe after prolonged friction. The wear and tear of the cartilage surface is more severe after prolonged friction. Patients with gouty arthritis should reduce the sudden speed changes such as fast running and variable speed running to maintain the stability of the cartilage surface friction coefficient.

Prediction of knee biomechanics with different tibial component malrotations after total knee arthroplasty: conventional machine learning vs. deep learning

The precise alignment of tibiofemoral components in total knee arthroplasty is a crucial factor in enhancing the longevity and functionality of the knee. However, it is a substantial challenge to quickly predict the biomechanical response to malrotation of tibiofemoral components after total knee arthroplasty using musculoskeletal multibody dynamics models. The objective of the present study was to conduct a comparative analysis between a deep learning method and four conventional machine learning methods for predicting knee biomechanics with different tibial component malrotation during a walking gait after total knee arthroplasty. First, the knee contact forces and kinematics with different tibial component malrotation in the range of ±5° in the three directions of anterior/posterior slope, internal/external rotation, and varus/valgus rotation during a walking gait after total knee arthroplasty were calculated based on the developed musculoskeletal multibody dynamics model. Subsequently, deep learning and four conventional machine learning methods were developed using the above 343 sets of biomechanical data as the dataset. Finally, the results predicted by the deep learning method were compared to the results predicted by four conventional machine learning methods. The findings indicated that the deep learning method was more accurate than four conventional machine learning methods in predicting knee contact forces and kinematics with different tibial component malrotation during a walking gait after total knee arthroplasty. The deep learning method developed in this study enabled quickly determine the biomechanical response with different tibial component malrotation during a walking gait after total knee arthroplasty. The proposed method offered surgeons and surgical robots the ability to establish a calibration safety zone, which was essential for achieving precise alignment in both preoperative surgical planning and intraoperative robotic-assisted surgical navigation.

Clinical relevance of roll-back replacement of ultra congruent total knee arthroplasty: comparison of mid-term outcomes with posterior stabilizing design

INTRODUCTION

The outcomes of total knee arthroplasty (TKA) remain controversial, and we do not know which factors are important for successful outcomes. This study aimed to compare the mid-term outcomes of different conceptual designs by evaluating the radiological and clinical outcomes.

MATERIALS AND METHODS

A total of 478 total knee arthroplasties (TKAs) were enrolled and allocated into groups I [posterior stabilizing (PS) with anterior referencing (AR)], II [PS with posterior referencing (PR), and III [ultra-congruent (UC) TKA)]. Preoperative findings, last follow-up clinical outcomes, and final follow-up radiological and indirect assessments of the femoral rollback were compared between the groups.

RESULTS

The mean follow-up period was 72.6 ± 12.9 months. The tourniquet was used samely applied to every group. Flexion contracture was significantly larger in group III than in groups I and II (3.3 ± 2.7, p < 0.001), and further flexion was significantly smaller in group III (130.0° ± 2.7°, p < 0.001). Among the radiological parameters, posterior osteophyte formation was the most common in group III (67.8%). The rollback distance was significantly smaller in group III than in groups I and II (p < 0.001). The active deep flexion angle was affected by the posterior condylar offset (PCO) ratio, and the contact point changed the distance (p < 0.05).

CONCLUSION

PS TKAs showed better ROMs than UC TKAs; however, no differences were noted in the clinical outcome scales. The flexion angle was affected by the PCOR and rollback at both PS and UC TKAs. However, rollback negatively affected the flexion angle during UC TKAs. An inappropriate femoral rollback was identified, and femoral osteophyte formation was determined to be the most prominent in UC TKAs. Level of evidence Level III comparative study.

The novel magnesium-titanium hybrid cannulated screws for the treatment of vertical femoral neck fractures: Biomechanical evaluation

Background

Conventional cannulated screws are commonly used for internal fixation in the treatment of vertical femoral neck fractures. However, the noticeably high rates of undesirable outcomes such as nonunion, malunion, avascular necrosis, and fixation failure still troubled the patients and surgeons. It is urgent to develop new cannulated screws to improve the above clinical problems. The purpose of this study was to design a novel magnesium-titanium hybrid cannulated screw and to further evaluate its biomechanical performance for the treatment of vertical femoral neck fractures.

Methods

A novel magnesium-titanium hybrid cannulated screw was designed, and the conventional titanium cannulated screw was also modeled. The finite element models for vertical femoral neck fractures with magnesium-titanium hybrid cannulated screws and conventional cannulated screws were respectively established. The hip joint contact force during walking gait calculated by a subject-specific musculoskeletal multibody dynamics model, was used as loads and boundary conditions for both finite element models. The stress and displacement distributions of the cannulated screws and the femur, the micromotion of the fracture surfaces of the femoral neck, and the overall stiffness were calculated and analyzed using finite element models. The biomechanical performance of the Magnesium-Titanium hybrid cannulated screws was evaluated.

Results

The maximum stresses of the magnesium-titanium hybrid cannulated screws and the conventional cannulated screws were 451.5 ​MPa and 476.8 ​MPa, respectively. The maximum stresses of the femur with the above different cannulated screws were 140.3 ​MPa and 164.8 ​MPa, respectively. The maximum displacement of the femur with the hybrid cannulated screws was 6.260 ​mm, lower than the femur with the conventional cannulated screws, which was 7.125 ​mm. The tangential micromotions in the two orthogonal directions at the fracture surface of the femoral neck with the magnesium-titanium hybrid cannulated screws were comparable to those with the conventional cannulated screws. The overall stiffness of the magnesium-titanium hybrid cannulated screw system was 490.17 ​N/mm, higher than that of the conventional cannulated screw system, which was 433.92 ​N/mm.

Conclusion

The magnesium-titanium hybrid cannulated screw had superior mechanical strength and fixation stability for the treatment of the vertical femoral neck fractures, compared with those of the conventional cannulated screw, indicating that the magnesium-titanium hybrid cannulated screw has great potential as a new fixation strategy in future clinical applications.The translational potential of this article: This study highlights an innovative design of the magnesium-titanium hybrid cannulated screw for the treatment of vertical femoral neck fractures. The novel magnesium-titanium hybrid cannulated screw not only to provide sufficient mechanical strength and fixation stability but also to contribute to the promotion of fracture healing, which could provide a better treatment for the vertical femoral neck fractures, beneficially reducing the incidence of nonunion and reoperation rates.

Conformity design can change the effect of tibial component malrotation on knee biomechanics after total knee arthroplasty

BACKGROUND

Component alignment is essential to improve knee function and survival in total knee arthroplasty. However, it is still unclear whether the conformity design of tibiofemoral component can mitigate abnormal knee biomechanics caused by component malrotation. The purpose of this study was to investigate whether the sagittal/coronal conformity design of the tibial component could change the effect of the tibial component malrotation on knee biomechanics in total knee arthroplasty.

METHODS

A developed patient-specific musculoskeletal multi-body dynamics model of total knee arthroplasty was used to investigate the effects of the sagittal/coronal conformity of the tibial component on knee contact forces and kinematics caused by tibial component malrotation during the walking gait.

FINDINGS

Medial and lateral contact forces, internal-external rotation, and anterior-posterior translation were significantly affected by tibial component malrotation after total knee arthroplasty during the walking gait. The lower sagittal conformity of the tibial component can mitigate the abnormal internal-external rotation caused by tibial component malrotation in total knee arthroplasty, the higher coronal conformity of the tibial component can mitigate the abnormal medial-lateral translation caused by tibial component malrotation in total knee arthroplasty.

INTERPRETATION

This study highlights the importance of the tibiofemoral conformity designs on knee biomechanics caused by component malrotation in total knee arthroplasty. The optimization of the tibiofemoral conformity designs should be thoroughly considered in the design of new implants and in the planning of surgical procedures.

Medial congruent polyethylene design show different tibiofemoral kinematics and enhanced congruency compared to a standard symmetrical cruciate retaining design for total knee arthroplasty-an in vivo randomized controlled study of gait using dynamic radiostereometry

PURPOSE

New total knee arthroplasty implant designs attempt to normalize kinematics patterns that may improve functional performance and patient satisfaction. It was hypothesized that a more medial congruent (MC) anatomic bearing design (1) influences the tibiofemoral kinematics and (2) enhances articular congruency compared to a standard symmetrical cruciate retaining (CR) bearing design.

METHODS

In this double-blinded randomized study, 66 patients with knee osteoarthritis were randomly included in two groups: MC (n = 31) and CR (n = 33). Clinical characteristics such as knee ligament lesions and knee osteoarthritis scores were graded on preoperative magnetic resonance imaging and radiography. At the 1-year follow-up, dynamic radiostereometric analysis was used to assess tibiofemoral joint kinematics and articulation congruency. Patient-reported outcome measures, Oxford Knee Score, the Forgotten Joint Score, and the Knee Osteoarthritis Outcome Score, were assessed preoperatively and at the 1-year follow-up.

RESULTS

Compared to the CR bearing, the MC bearing displayed an offset with approximately 3 mm greater anterior tibial drawer (p < 0.001) during the entire motion, and up to approximately 3.5 degrees more tibial external rotation (p = 0.004) from mid-swing to the end of the gait cycle at the 1-year follow-up. Furthermore, the congruency area in the joint articulation was larger during approximately 80% of the gait cycle for the MC bearing compared to the CR. The patient-reported outcome measures improved (p < 0.001), but there were no differences between groups. In addition, there were no differences in clinical characteristics and there were no knee revisions or recognized deep infections during follow-up.

CONCLUSION

The study demonstrates that the MC-bearing design changes tibiofemoral kinematics and increases the area of congruency towards more native knee kinematics than the CR bearing. In perspective this may contribute to a more stabilized knee motion, restoring the patient's confidence in knee function during daily activities.

Articular geometry can affect joint kinematics, contact mechanics, and implant-bone micromotion in total ankle arthroplasty

Implant loosening and bearing surface wear remain the most common failure problems of total ankle arthroplasty (TAA). One of the main factors leading to these problems is the nonphysiologic design of articular surfaces. The goals of this study were to reveal the effects of the anatomical medial-lateral borders height differences, coronal and sagittal radii on the joint kinematics, contact mechanics, and implant-bone micromotion in TAA. A previously developed and validated musculoskeletal (MSK) multibody dynamics (MBD) modeling method of TAA based on AnyBody generic MSK MBD model (five simulations for each implant) was used by combining with a finite element analysis. Five ankle implant models with different articular surface morphologies were created according to the anatomic characteristics of Chinese measurement data, marked as Implant A to E. The total ankle forces and motions during walking simulation were predicted by MSK MBD models and the contact mechanics of the bearing surface and the micromotion of the implant-bone interface of TAA were predicted by FE models. Compared with Implant A, the internal-external rotation in Implant E increased by 12.14%, the maximum of anterior-posterior translation in Implant E increased by 5.62%, the maximum reduction of tibial micromotion in Implant E was 59.98%, and for talar, micromotion was 15.36%. The ankle implant with similar anatomic articular surface has the potential to allow patients to recover better motions and reduce the risk of early loosening. This study would provide design guidance for the development of new ankle implants and further advance the development of TAA. Clinical Significance: This study promoted the improvement of ankle implant design and made contributions to improve the service life of ankle implant and patient satisfaction.

Comparison of joint load, motions and contact stress and bone-implant interface micromotion of three implant designs for total ankle arthroplasty

BACKGROUND AND OBJECTIVE

Loosening and wear are still the main problems for the failure of total ankle arthroplasty, which are closely related to the micromotion at the bone-implant interface and the contact stress and joint motions at the articular surfaces. Implant design is a key factor to influence the ankle force, motions, contact stress, and bone-implant interface micromotion. The purpose of this study is to evaluate the differences in these parameters of INBONE II, INFINITY, and a new anatomic ankle implant under the physiological walking gait of three patients.

METHODS

This was achieved by using an in-silico simulation framework combining patient-specific musculoskeletal multibody dynamics and finite element analysis. Each implant was implanted into the musculoskeletal multibody dynamics model, respectively, which was driven by the gait data to calculate ankle forces and motions. These were then used as the boundary conditions for the finite element model, and the contact stress and the bone-implant interface micromotions were calculated.

RESULTS

The total ankle contact forces were not significantly affected by articular surface geometries of ankle implants. The range of motion of the ankle joint implanted with INFINITY was a little larger than that with INBONE II. The anatomic ankle implant design produced a greater range of motion than INBONE II, especially the internal-external rotation. The fixation design of INFINITY achieved lower bone-implant interface micromotion compared with INBONE II. The anatomic ankle implant design produced smaller contact stress with no evident edge contact and a smaller tibia-implant interface micromotion. In addition, significant differences in the magnitudes and tendencies of total ankle contact forces and motions among different patients were found.

CONCLUSIONS

The articular surface geometry of ankle implants not only affected the ankle motions and contact stress distribution but also affected the bone-implant interface micromotions. The anatomic ankle implant had good performance in recovering ankle joint motion, equalizing contact stress, and reducing bone-implant interface micromotion. INFINITY's fixation design could achieve smaller bone-implant interface micromotion than INBONE II.

Kinematics and kinetics comparison of ultra-congruent versus medial-pivot designs for total knee arthroplasty by multibody analysis

Nowadays, several configurations of total knee arthroplasty (TKA) implants are commercially available whose designs resulted from clinical and biomechanical considerations. Previous research activities led to the development of the so-called medial-pivot (MP) design. However, the actual benefits of the MP, with respect to other prosthesis designs, are still not well understood. The present work compares the impact of two insert geometries, namely the ultra-congruent (UC) and medial-pivot (MP), on the biomechanical behaviour of a bicondylar total knee endoprosthesis. For this purpose, a multibody model of a lower limb was created alternatively integrating the two implants having the insert geometry discretized. Joint dynamics and contact pressure distributions were evaluated by simulating a squat motion. Results showed a similar tibial internal rotation range of about 3.5°, but an early rotation occurs for the MP design. Furthermore, the discretization of the insert geometry allowed to efficiently derive the contact pressure distributions, directly within the multibody simulation framework, reporting peak pressure values of 33 MPa and 20 MPa for the UC and MP, respectively. Clinically, the presented findings confirm the possibility, through a MP design, to achieve a more natural joint kinematics, consequently improving the post-operative patient satisfaction and potentially reducing the occurrence of phenomena leading to the insert loosening.

Increasing the height of the anterior lip on a tibial insert in a posterior stabilized knee prosthesis has little effect on the wear rate

A high anterior lip on a total knee prosthesis is an effective way of reducing anterior translation, but the effect on joint wear is unclear. Using finite element analysis (FEA), this study quantitatively compared wear rates and anterior contact stresses in three posterior stabilized knee prostheses with different heights for the anterior lip during six daily activities (walking, stair ascent, stair descent, sit-to-stand, pivot turn and crossover turn). The wear rate and location of maximum wear depth were similar for the three lip heights tested, but the knee with the highest anterior lip also showed slight anterior wear scaring due to articular contact stress during swing phase, which was highly dependent on the shape of the contact interface. This study illustrates that tibial inserts with a high anterior lip maintain a wear rate similar to moderate and low lip posterior stabilized designs.

Patient-specific musculoskeletal models as a framework for comparing ACL function in unicompartmental versus bicruciate retaining arthroplasty

Unicompartmental knee arthroplasty has been shown to provide superior functional outcomes compared to total knee arthroplasty and have motivated development of advanced implant designs including bicruciate retaining knee arthroplasty. However, few validated frameworks are available to directly compare the effect of implant design and surgical techniques on ligament function and joint kinematics. In the present study, the subject-specific lower extremity models were developed based on musculoskeletal modeling framework using force-dependent kinematics method, and validated against in vivo telemetric data. The experiment data of two subjects who underwent TKA were obtained from the SimTK "Grand Challenge Competition" repository, and integrated into the subject-specific lower extremity model. Five walking gait trials and three different knee implant models for each subject were used as partial inputs for the model to predict knee biomechanics for unicompartmental, bicruciate retaining, and total knee arthroplasty. The results showed no significant differences in the tibiofemoral contact forces or angular kinematic parameters between three groups. However, unicompartmental knee arthroplasty demonstrated significantly more posterior tibial location between 0% and 40% of the gait cycle (p < 0.017). Significant differences in range of tibiofemoral anterior/posterior translation and medial/lateral translation were also observed between unicompartmental and bicruciate retaining arthroplasty (p < 0.017). Peak values of anterior cruciate ligament forces differed between unicompartmental and bicruciate retaining arthroplasty from 10% to 30% of the gait cycle. Findings of this study indicate that unicompartmental and bicruciate retaining arthroplasty do not have identical biomechanics and point to the complementary role of anterior cruciate ligament and articular geometry in guiding knee function. Further, the patient-specific musculoskeletal model developed provides a reliable framework for assessing new implant designs, and effect of surgical techniques on knee biomechanics following arthroplasty.

Variation and trends in reasons for knee replacement revision: a multi-registry study of revision burden

Background and purpose - Studies describing time-related change in reasons for knee replacement revision have been limited to single regions or institutions, commonly analyze only 1st revisions, and may not reflect true caseloads or findings from other areas. We used revision procedure data from 3 arthroplasty registries to determine trends and differences in knee replacement revision diagnoses.Patients and methods - We obtained aggregated data for 78,151 revision knee replacement procedures recorded by the Swedish Knee Arthroplasty Register (SKAR), the Australian Orthopaedic Association National Joint Replacement Registry (AOANJRR), and the Kaiser Permanente Joint Replacement Registry (KPJRR) for the period 2003-2017. Equivalent diagnosis groups were created. We calculated the annual proportions of the most common reasons for revision.Results - Infection, loosening, and instability were among the 5 most common reasons for revision but magnitude and ranking varied between registries. Over time there were increases in proportions of revisions for infection and decreases in revisions for wear. There were inconsistent proportions and trends for the other reasons for revision. The incidence of revision for infection showed a uniform increase.Interpretation - Despite some differences in terminology, comparison of registry-recorded revision diagnoses is possible, but defining a single reason for revision is not always clear-cut. There were common increases in revision for infection and decreases in revision for wear, but variable changes in other categories. This may reflect regional practice differences and therefore generalizability of studies regarding reasons for revision is unwise.

Effect of Ligament Properties on Nonlinear Dynamics and Wear Prediction of Knee Prostheses

Although wear is known as the primary cause of long-time failure of total knee arthroplasty (TKA), it can be vital in short- and midterm TKA failure due to laxity. One of the reasons leading to joint laxity and instability is ligamentous insufficiency. This study, therefore, aims to investigate the effects of insufficient ligaments-related knee laxity on both nonlinear dynamics and wear of TKA. The study hypothesizes (a) ligamentous insufficiency can increase TKA damage; (b) stiffness reduction of each of the posterior cruciate ligament (PCL) and medial-lateral collateral ligaments (MCL-LCL) can differently contribute to TKA damage. A forward dynamics methodology is developed and the ligament behavior is simulated employing an asymmetric nonlinear elastic model. External loads and moment, due to the presence of all soft tissues, e.g., muscles and hip joint reaction forces, applied to the femoral bone are determined using a musculoskeletal approach linked to the developed model. A mesh density analysis is performed and comparing outcomes with that available in the literature allows for the assessment of our approach. From the results acquired, reduced PCL stiffness leads to an increase in linear wear rates and results in the maximum damage in TKAs. However, the maximum linear wear rates on both condyles occur once the stiffness of all ligaments is reduced. Moreover, the worn area of the tibia surface increases with the reduction in MCL-LCL stiffness on the medial condyle. The joint with insufficient PCL also shows a considerable increase in ligament forces right after toe-off.

Kinematics and center of axial rotation during walking after medial pivot type total knee arthroplasty

PURPOSE

In recent years, the medial pivot (MP) type total knee arthroplasty (TKA) implant has been developed and marketed for achieving more natural kinematics with MP. However, little is known about the pivot pattern during walking after MP type TKA. This study aimed to determine the kinematics and center of axial rotation during walking after MP type TKA.

METHODS

This randomized prospective study enrolled 40 patients with MP type TKA, 20 with cruciate-substituting TKA (MP-CS group), 20 with posterior-stabilized TKA (MP-PS group), and 10 healthy volunteers (control group). The kinematics and center of axial rotation during overground walking were measured by a three-dimensional motion analysis system. The six-degrees-of-freedom kinematics of the knee were calculated by the point cluster method.

RESULTS

The amount of change in knee flexion in early stance phase was significantly lower in the MP-CS and MP-PS groups than in the control group. The femur showed anterior translation during early stance phase in all three groups. The median center of axial rotation in the transverse plane was predominantly on the lateral side of the knee during stance in all groups.

CONCLUSIONS

Kinematics during gait are thought to be determined by physical posture, the kinetic chain during weight-bearing, and the kinematic features of adjacent structures, such as the behavior of the biarticular muscles. MP-CS and MP-PS did not necessarily induce rotational motion centered on the medial ball-in-socket component during walking; translational and lateral pivoting movements were also observed. Long-term follow-up is needed to monitor for polyethylene wear and implant loosening.

Leveraging subject-specific musculoskeletal modeling to assess effect of anterior cruciate ligament retaining total knee arthroplasty during walking gait

Bi-cruciate retaining total knee arthroplasty has several potential advantages including improved anteroposterior knee stability compared to contemporary posterior cruciate-retaining total knee arthroplasty. However, few studies have explored whether there is significant differences of knee biomechanics following bi-cruciate retaining total knee arthroplasty compared to posterior cruciate-retaining total knee arthroplasty. In the present study, subject-specific lower extremity musculoskeletal multi-body dynamics models for bi-cruciate retaining, bi-cruciate retaining without anterior cruciate ligament, and posterior cruciate-retaining total knee arthroplasty were developed based on the musculoskeletal modeling framework using force-dependent kinematics method and validated against in vivo telemetric data. The experiment data of two subjects who underwent total knee arthroplasty were obtained for the SimTK “Grand Challenge Competition” repository, and integrated into the musculoskeletal model. Five walking gait trials for each subject were used as partial inputs for the model to predict the knee biomechanics for bi-cruciate retaining, bi-cruciate retaining without anterior cruciate ligament, and posterior cruciate-retaining total knee arthroplasty. The results revealed significantly greater range of anterior/posterior tibiofemoral translation, and significantly more posterior tibial location during the early phase of gait and more anterior tibial location during the late phase of gait were found in bi-cruciate retaining total knee arthroplasty without anterior cruciate ligament when compared to the bi-cruciate retaining total knee arthroplasty. No significant differences in tibiofemoral contact forces, rotations, translations, and ligament forces between bi-cruciate retaining and posterior cruciate-retaining total knee arthroplasty during normal walking gait, albeit slight differences in range of tibiofemoral internal/external rotation and anterior/posterior translation were observed. The present study revealed that anterior cruciate ligament retention has a positive effect on restoring normal knee kinematics in bi-cruciate retaining total knee arthroplasty. Preservation of anterior cruciate ligament in total knee arthroplasty and knee implant designs interplay each other and both contribute to restoring normal knee kinematics in different types of total knee arthroplasty. Further evaluation of more demanding activities and subject data from patients with bi-cruciate retaining and posterior cruciate-retaining total knee arthroplasty via musculoskeletal modeling may better highlight the role of the anterior cruciate ligament and its stabilizing influence.