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Fiedler B, Bieganowski T, Anil U, Lin CC, Habibi AA, Schwarzkopf R. Can pain be improved with retention of the posterior cruciate ligament during total knee arthroplasty? EUROPEAN JOURNAL OF ORTHOPAEDIC SURGERY & TRAUMATOLOGY : ORTHOPEDIE TRAUMATOLOGIE 2023; 33:3395-3401. [PMID: 37140671 DOI: 10.1007/s00590-023-03562-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Accepted: 04/23/2023] [Indexed: 05/05/2023]
Abstract
PURPOSE The purpose of the current study was to determine if differences exist between cruciate-retaining (CR) and posterior-stabilized (PS) implant articulations for total knee arthroplasty (TKA) with regards to early post-operative pain. METHODS We retrospectively reviewed patients who underwent primary TKA, with the same TKA implant design, at our institution between January 2018 and July 2021. Patients were stratified based on whether they received a CR or non-constrained PS (PSnC) articulation and propensity score matched in a 1:1 ratio. A sub-analysis matching patient who received a constrained PS implant (PSC) to those undergoing CR TKA and PSnC TKA was also carried out. Opioid dosages were converted to morphine milligram equivalents (MME). RESULTS 616 patients after CR TKA were matched 1:1 to 616 patients with a PSnC implant. There were no significant differences between demographic variables. There were no statistically significant differences in opioid usage measured by MME on post-operative day (POD) 0 (p = 0.171), POD1 (p = 0.839), POD2 (p = 0.307), or POD3 (p = 0.138); VAS pain scores (p = 0.175); or 90-day readmission rate for pain (p = 0.654). A sub-analysis of CR versus PSC TKA demonstrated no significant differences in opioid usage on POD0 (p = 0.765), POD1 (p = 0.747), POD2 (p = 0.564), POD3 (p = 0.309); VAS pain scores (p = 0.293); and 90-day readmission rate for pain (p > 0.9). CONCLUSION Our analysis demonstrated no significant difference in post-operative VAS pain scores and MME usage based on implant. The results suggest that neither the type of articulation or constraint used for primary TKA has a significant impact on immediate post-operative pain and opioid consumption. LEVEL III EVIDENCE Retrospective Cohort Study.
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Affiliation(s)
- Benjamin Fiedler
- Department of Orthopedic Surgery, NYU Langone Orthopedic Center, NYU Langone Health, 301 East 17th Street, 14th Floor, New York, NY, USA
| | - Thomas Bieganowski
- Department of Orthopedic Surgery, NYU Langone Orthopedic Center, NYU Langone Health, 301 East 17th Street, 14th Floor, New York, NY, USA
| | - Utkarsh Anil
- Department of Orthopedic Surgery, NYU Langone Orthopedic Center, NYU Langone Health, 301 East 17th Street, 14th Floor, New York, NY, USA
| | - Charles C Lin
- Department of Orthopedic Surgery, NYU Langone Orthopedic Center, NYU Langone Health, 301 East 17th Street, 14th Floor, New York, NY, USA
| | - Akram A Habibi
- Department of Orthopedic Surgery, NYU Langone Orthopedic Center, NYU Langone Health, 301 East 17th Street, 14th Floor, New York, NY, USA
| | - Ran Schwarzkopf
- Department of Orthopedic Surgery, NYU Langone Orthopedic Center, NYU Langone Health, 301 East 17th Street, 14th Floor, New York, NY, USA.
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Shah D, Hauschild J, Hope D, Vizurraga D. Stress Radiograph Confirmation of Translational Instability After Cruciate-Retaining Total Knee Arthroplasty. J Am Acad Orthop Surg Glob Res Rev 2022; 6:01979360-202204000-00015. [PMID: 35427253 PMCID: PMC10566871 DOI: 10.5435/jaaosglobal-d-22-00062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 02/19/2022] [Indexed: 06/14/2023]
Abstract
INTRODUCTION Late rupture of the posterior cruciate ligament (PCL) in cruciate-retaining total knee arthroplasty (TKA) can lead to increased AP instability. This results in increased stress on the medial hamstrings resulting in hamstring-based pain. We looked to identify patients with late PCL failure using a lateral stress radiograph. METHODS A prospective cohort analysis was completed at a single institution. Eligible patients were divided into two groups based on the amount of anterior knee pain. Pain was defined as a visual analog scale of greater than or equal to 3. Each group completed a visual analog scale, Knee Injury and Osteoarthritis Outcome Score Junior, Patient-Reported Outcome Measurement Information System score and underwent a lateral posterior stress/nonstress radiograph. Amount of posterior translation and posterior tibial slope was measured. RESULTS Patients who had painful TKAs at the follow-up had lower Knee Injury and Osteoarthritis Outcome Score Junior (45.86 ± 13.52 versus 78.00 ± 13.26 P < 0.001). Those patients were also found to have significantly higher posterior tibial translation with stress radiograph (6.89 ± 1.874 versus 3.91 ± 2.15 mm P < 0.001) and significantly increased tibial slope (6.51 ± 2.37° versus 3.98 ± 1.79°, P = 0.004). Seven of the 14 patients in the pain group underwent revision surgery, with 6 patients found to have incompetent PCLs. DISCUSSION Patients with increased AP translation and increased posterior tibial slope after cruciate-retaining TKA are likely to have worse pain and outcome measures.
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Affiliation(s)
- Darshan Shah
- From the Department of Orthopaedics and Rehabilitation, Brooke Army Medical Center, San Antonio, TX
| | - Jordan Hauschild
- From the Department of Orthopaedics and Rehabilitation, Brooke Army Medical Center, San Antonio, TX
| | - Donald Hope
- From the Department of Orthopaedics and Rehabilitation, Brooke Army Medical Center, San Antonio, TX
| | - David Vizurraga
- From the Department of Orthopaedics and Rehabilitation, Brooke Army Medical Center, San Antonio, TX
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Research on the Wear Performance of Artificial Knee Joint with Different Geometric Dimension. J Med Biol Eng 2022. [DOI: 10.1007/s40846-022-00679-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Shu L, Sato T, Hua X, Sugita N. Comparison of Kinematics and Contact Mechanics in Normal Knee and Total Knee Replacements: A Computational Investigation. Ann Biomed Eng 2021; 49:2491-2502. [PMID: 34142278 DOI: 10.1007/s10439-021-02812-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Accepted: 06/09/2021] [Indexed: 10/21/2022]
Abstract
An objective of total knee replacement (TKR) is to restore the mechanical function of a normal knee. Joint kinematics and contact mechanics performance are two of the primary indices that indicate the success of TKR devices. The aim of this study was to compare the kinematics and contact mechanics of TKR and normal knee joints. An experimentally evaluated finite-element (FE) knee model was developed and used to investigate the performance of four TKR designs (fixed cruciate-retaining (CR), mobile CR, posterior-stabilized (PS), medial pivot design (MP)) and the normal knee joint during a gait cycle. The predicted kinematic results showed that the MP design presented similar kinematics to those of the normal knee joint and did not demonstrate paradoxical motion of the femur. A considerably larger contact area and lower contact pressure were found on the normal knee joint (1315 mm2, and 14.8 MPa, respectively) than on the TKRs, which was consistent with the previous in-vivo fluoroscopic investigation. The mobile CR and PS designs exhibited the smallest and greatest contact pressures of the four TKR designs, respectively. The results of the present study help to understand the kinematics and contact mechanics in the TKR during the gait cycle, and provide comprehensive information about the performance of the normal knee joint.
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Affiliation(s)
- Liming Shu
- Department of Mechanical Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
| | | | - Xijin Hua
- Department of Engineering, Institute for Manufacturing, University of Cambridge, Cambridge, CB2 1PZ, UK
| | - Naohiko Sugita
- Department of Mechanical Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan
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Lee JA, Koh YG, Kang KT. Effect of post-cam design on the kinematics and contact stress of posterior-stabilized total knee arthroplasty. Biomed Mater Eng 2021; 32:323-332. [PMID: 33967034 DOI: 10.3233/bme-201097] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
BACKGROUND The post-cam mechanism in the posterior-stabilized (PS) implant plays an important role, such as durability and kinematic performances, in total knee arthroplasty (TKA). OBJECTIVE The purpose of this study was to evaluate the difference in the kinematics and contact stress of five post-cam designs, which are flat-and-flat, curve-and-curve (concave), curve-and-curve (concave and convex), helical, and asymmetrical post-cam designs, using three-dimensional finite element models. METHODS We designed the post-cam model with five different geometries. The kinematics, contact stress, and contact area were evaluated in the five post-cam designs under gait cycle loading conditions using the finite element method. RESULTS There were no differences in the contact stress and area on the tibial insert in all designs. The largest internal rotation was shown in the swing phase for the helical design, and the largest tibial posterior translation was observed for the curve-and-curve (concave) design. The curve-and-curve (concave) design showed the lowest contact stress and the largest posterior tibial translation during the gait cycle. CONCLUSIONS Considering the kinematics and contact stress, we found that the curve-and-curve (concave) design was more stable than other designs. From the results, we found the important factors of TKA implant considering stability and kinematics.
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Affiliation(s)
- Jin-Ah Lee
- Department of Mechanical Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul, Republic of Korea
| | - Yong-Gon Koh
- Joint Reconstruction Center, Department of Orthopaedic Surgery, Yonsei Sarang Hospital, 10 Hyoryeong-ro, Seocho-gu, Seoul, Republic of Korea
| | - Kyoung-Tak Kang
- Joint Reconstruction Center, Department of Orthopaedic Surgery, Yonsei Sarang Hospital, 10 Hyoryeong-ro, Seocho-gu, Seoul, Republic of Korea
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Zaylor W, Stulberg BN, Halloran JP. Use of distraction loading to estimate subject-specific knee ligament slack lengths. J Biomech 2019; 92:1-5. [DOI: 10.1016/j.jbiomech.2019.04.040] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Revised: 04/29/2019] [Accepted: 04/29/2019] [Indexed: 10/26/2022]
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Symmetrical cruciate-retaining versus medial pivot prostheses: The effect of intercondylar sagittal conformity on knee kinematics and contact mechanics. Comput Biol Med 2019; 108:101-110. [DOI: 10.1016/j.compbiomed.2019.03.005] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2018] [Revised: 03/06/2019] [Accepted: 03/07/2019] [Indexed: 01/28/2023]
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Zhang Q, Chen Z, Zhang J, Hu J, Peng Y, Fan X, Jin Z. Insert conformity variation affects kinematics and wear performance of total knee replacements. Clin Biomech (Bristol, Avon) 2019; 65:19-25. [PMID: 30953916 DOI: 10.1016/j.clinbiomech.2019.03.016] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/12/2018] [Revised: 03/19/2019] [Accepted: 03/25/2019] [Indexed: 02/07/2023]
Abstract
BACKGROUND The insert conformity is a critical factor for successful total knee replacement which must be considered in design of the implant. However, the effects of conformity on knee kinematics and wear under physiological environment are often neglected in previous studies. The present study involved evaluating the biomechanics and wear performance with regard to different insert conformity in total knee replacement. METHODS Different tibial inserts with different sagittal and coronal conformity levels were created and analyzed using a previously developed wear prediction framework, coupling a patient-specific musculoskeletal multibody dynamics simulation, finite element and wear analysis. The contact mechanics, kinematics, and wear performance were compared during 10 million cycles of wear simulation. FINDINGS The findings revealed that the knee kinematics was affected by sagittal conformity design variables, which further influenced the wear of insert bearing surface. Additionally, kinematics and wear of artificial knee joint were much more sensitive to sagittal than coronal conformity of tibial insert. The lower sagittal conformity designs had lower wear rates, worn area and contact area. In turn, the wear of insert bearing surface also changed insert conformity, and further impacted on knee kinematics. INTERPRETATION The present study indicated that the sagittal conformity design of insert surface played a crucial role to improve contact mechanics and kinematics performance and minimize wear of total knee replacement. The optimization of insert conformity should be considered carefully in implant design and surgical procedures.
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Affiliation(s)
- Qida Zhang
- State Key Laboratory for Manufacturing System Engineering, School of Mechanical Engineering, Xi'an Jiaotong University, No.28, Xianning West Road, Xi'an, 710049, China
| | - Zhenxian Chen
- Key Laboratory of Road Construction Technology and Equipment (Ministry of Education), School of Mechanical Engineering, Chang'an University, Middle-section of Nan'er Huan Road, Xi'an 710064, China.
| | - Jing Zhang
- State Key Laboratory for Manufacturing System Engineering, School of Mechanical Engineering, Xi'an Jiaotong University, No.28, Xianning West Road, Xi'an, 710049, China
| | - Jiayu Hu
- State Key Laboratory for Manufacturing System Engineering, School of Mechanical Engineering, Xi'an Jiaotong University, No.28, Xianning West Road, Xi'an, 710049, China
| | - Yinghu Peng
- State Key Laboratory for Manufacturing System Engineering, School of Mechanical Engineering, Xi'an Jiaotong University, No.28, Xianning West Road, Xi'an, 710049, China
| | - Xunjian Fan
- State Key Laboratory for Manufacturing System Engineering, School of Mechanical Engineering, Xi'an Jiaotong University, No.28, Xianning West Road, Xi'an, 710049, China
| | - Zhongmin Jin
- State Key Laboratory for Manufacturing System Engineering, School of Mechanical Engineering, Xi'an Jiaotong University, No.28, Xianning West Road, Xi'an, 710049, China; Tribology Research Institute, School of Mechanical Engineering, Southwest Jiaotong University, Xibu Yuanqu, Gaoxin District, Chengdu 610031, China; Institute of Medical and Biological Engineering, School of Mechanical Engineering, University of Leeds, Leeds LS2 9JT, UK
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Koh YG, Park KM, Lee HY, Kang KT. Influence of tibiofemoral congruency design on the wear of patient-specific unicompartmental knee arthroplasty using finite element analysis. Bone Joint Res 2019; 8:156-164. [PMID: 30997041 PMCID: PMC6444019 DOI: 10.1302/2046-3758.83.bjr-2018-0193.r1] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Objectives Unicompartmental knee arthroplasty (UKA) is an alternative to total knee arthroplasty for patients who require treatment of single-compartment osteoarthritis, especially for young patients. To satisfy this requirement, new patient-specific prosthetic designs have been introduced. The patient-specific UKA is designed on the basis of data from preoperative medical images. In general, knee implant design with increased conformity has been developed to provide lower contact stress and reduced wear on the tibial insert compared with flat knee designs. The different tibiofemoral conformity may provide designers the opportunity to address both wear and kinematic design goals simultaneously. The aim of this study was to evaluate wear prediction with respect to tibiofemoral conformity design in patient-specific UKA under gait loading conditions by using a previously validated computational wear method. Methods Three designs with different conformities were developed with the same femoral component: a flat design normally used in fixed-bearing UKA, a tibia plateau anatomy mimetic (AM) design, and an increased conforming design. We investigated the kinematics, contact stress, contact area, wear rate, and volumetric wear of the three different tibial insert designs. Results Conforming increased design showed a lower contact stress and increased contact area. In addition, increased conformity resulted in a reduction of the wear rate and volumetric wear. However, the increased conformity design showed limited kinematics. Conclusion Our results indicated that increased conformity provided improvements in wear but resulted in limited kinematics. Therefore, increased conformity should be avoided in fixed-bearing patient-specific UKA design. We recommend a flat or plateau AM tibial insert design in patient-specific UKA. Cite this article: Y-G. Koh, K-M. Park, H-Y. Lee, K-T. Kang. Influence of tibiofemoral congruency design on the wear of patient-specific unicompartmental knee arthroplasty using finite element analysis. Bone Joint Res 2019;8:156–164. DOI: 10.1302/2046-3758.83.BJR-2018-0193.R1.
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Affiliation(s)
- Y-G Koh
- Joint Reconstruction Center, Department of Orthopaedic Surgery, Joint Reconstruction Center, Department of Orthopaedic Surgery, Yonsei Sarang Hospital, Seoul, South Korea
| | - K-M Park
- Department of Mechanical Engineering, Department of Mechanical Engineering, Yonsei University, Seoul, South Korea
| | - H-Y Lee
- Department of Mechanical Engineering, Department of Mechanical Engineering, Yonsei University, Seoul, South Korea
| | - K-T Kang
- Department of Mechanical Engineering, Department of Mechanical Engineering, Yonsei University, Seoul, South Korea
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Koh YG, Son J, Kwon OR, Kwon SK, Kang KT. Tibiofemoral conformity variation offers changed kinematics and wear performance of customized posterior-stabilized total knee arthroplasty. Knee Surg Sports Traumatol Arthrosc 2019; 27:1213-1223. [PMID: 29974167 DOI: 10.1007/s00167-018-5045-9] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/16/2018] [Accepted: 06/27/2018] [Indexed: 01/17/2023]
Abstract
PURPOSE Posterior-stabilized (PS)-total knee arthroplasty (TKA) can be applied in any of several variations in terms of the tibiofemoral conformity and post-cam mechanism. However, previous studies have not evaluated the effect of the condylar surface radii (tibiofemoral conformity) on wear in a customized PS-TKA. The present study involved evaluating the wear performance with respect to three different conformities of the tibiofemoral articular surface in a customized PS-TKA by means of a computational simulation. METHODS An adaptive computational simulation method was developed that conduct wear simulation for tibial insert to predict kinematics, weight loss due to wear, and wear contours to results. Wear predictions using computational simulation were performed for 5 million gait cycles with force-controlled inputs. Customized PS-TKA designs were developed and categorized as conventional conformity (CPS-TKA), medial pivot conformity (MPS-TKA), and anatomical conformity (APS-TKA). The post-cam design in the customized PS-TKA is identical. We compared the kinematics, contact mechanics, and wear performance. RESULTS The findings revealed that APS-TKA exhibited the highest internal tibial rotation relative to other TKA designs. Additionally, the higher contact area led to there being less contact stress although it did not directly affect the wear performance. Specifically, MPS-TKA exhibited the lowest volumetric wear. CONCLUSIONS The results of the present study showed that tibiofemoral articular surface conformity should be considered carefully in customized PS-TKA design. Different wear performances were observed with respect to different tibiofemoral conformities. Even though APS-TKA exhibited an inferior wear performance compared to MPS-TKA, it proved to be better in terms of kinematics so its functionality may be improved through the optimization of the tibiofemoral articular surface conformity. Additionally, it should be carefully designed since any changes may affect the post-cam mechanism.
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Affiliation(s)
- Yong-Gon Koh
- Joint Reconstruction Center, Department of Orthopaedic Surgery, Yonsei Sarang Hospital, 10 Hyoryeong-ro, Seocho-gu, Seoul, 06698, Republic of Korea
| | - Juhyun Son
- Department of Mechanical Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea
| | - Oh-Ryong Kwon
- Joint Reconstruction Center, Department of Orthopaedic Surgery, Yonsei Sarang Hospital, 10 Hyoryeong-ro, Seocho-gu, Seoul, 06698, Republic of Korea
| | - Sae Kwang Kwon
- Joint Reconstruction Center, Department of Orthopaedic Surgery, Yonsei Sarang Hospital, 10 Hyoryeong-ro, Seocho-gu, Seoul, 06698, Republic of Korea
| | - Kyoung-Tak Kang
- Department of Mechanical Engineering, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul, 03722, Republic of Korea.
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Abstract
BACKGROUND Revision of TKA as a result of polyethylene wear is decreasing, but long-term wear performance of polyethylene is still a topic of interest to surgeons and device manufacturers seeking to improve longevity. Measuring wear of modern, wear-resistant implants has been described using radiostereometric analysis (RSA). Performing in vivo measurements would establish whether implant retrieval studies are representative of wear in well-performing knees. QUESTIONS/PURPOSES For a single knee implant system, we sought to determine (1) the linear wear rate using RSA; (2) the association between demographic factors and wear rate; and (3) the association between limb alignment and wear rate. METHODS A total of 49 patients with a minimum followup of 10 years (median, 12 years; range, 10-20 years) were retrospectively selected. During the examined period, 4082 TKAs were performed of which 2085 were the implant examined in this study. There were 71 of these patients who met the criteria including an available full-leg radiograph postoperatively, and 34 of these patients returned for examination along with 15 additional from a separate RSA study that also met the criteria. All patients received a posterior-stabilized, cobalt-chromium-on-conventional polyethylene total knee implant from a single implant system, which was the most commonly used at our institution at the time. Patients underwent standing RSA examinations from 0° to 120° of flexion at a single time point without the use of marker beads. Linear wear rates (including creep) were measured based on intersections between the femoral component and tibial insert models. Associations between wear and patient age at surgery, sex, height, weight, body mass index, tibial insert size, and limb alignment were examined. RESULTS Using the maximum linear wear rate from any flexion angle, the lateral rate was 0.047 mm/year (interquartile range [IQR], 0.034-0.066 mm/year) and the medial rate was 0.052 mm/year (IQR, 0.040-0.069 mm/year). Using the median of the linear wear rates across all flexion angles, the lateral rate was 0.027 mm/year (IQR, 0.017-0.046 mm/year) and the medial rate was 0.038 mm/year (IQR, 0.022-0.054 mm/year). This rate for males was 0.049 mm/year medially (IQR, 0.042-0.077 mm/year) and 0.032 mm/year laterally (IQR, 0.026-0.059 mm/year), and for females was 0.027 mm/year medially (0.016-0.039 mm/year) and 0.020 mm/year laterally (IQR, 0.013-0.032 mm/year). The wear rate for males was greater medially (difference = 0.022 mm/year, p < 0.001) and laterally (difference = 0.012 mm/year, p = 0.008). There were associations between greater wear and increasing height (ρ = 0.48, p < 0.001 medially and ρ = 0.30, p = 0.04 laterally), decreasing body mass index (ρ = -0.31, p = 0.03 medially), and greater implant size (ρ = 0.34, p = 0.02 medially). Increasingly varus leg alignment was associated with greater medial wear (ρ = 0.33, p = 0.02). CONCLUSIONS Greater wear rates were associated with demographic factors and leg alignment. Further RSA wear studies of other modern implant systems would provide complementary information to retrieval studies and valuable data on wear resistance. CLINICAL RELEVANCE Good wear resistance was demonstrated by well-performing implants in patients at long-term followup with wear magnitudes in agreement with reported values from retrieval studies.
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Ardestani MM, Moazen M. How human gait responds to muscle impairment in total knee arthroplasty patients: Muscular compensations and articular perturbations. J Biomech 2016; 49:1620-1633. [DOI: 10.1016/j.jbiomech.2016.03.047] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Revised: 03/24/2016] [Accepted: 03/25/2016] [Indexed: 10/22/2022]
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