Sagittal radius of curvature, trochlea design and ultracongruent insert in total knee arthroplasty

Multi radius (MR) total knee arthroplasty (TKA) has been associated with mid-flexion instability. Single radius (SR) TKA may provide better anteroposterior stability through single flexion axis and biomechanical advantage for quadriceps function. Medial pivot (MP) TKA and gradually reducing (GR) radius TKA produce better knee kinematics. Clinical outcomes are equivalent for SR, MR and MP TKA. Short-term studies have shown better clinical outcomes and kinematics for GR TKA. Thinner and narrow anterior flange, deeper trochlea groove and more anatomical trochlea design reduces patellofemoral complications in TKA Ultracongruent inserts provide comparable clinical outcomes to posterior-stabilized TKA and cruciate retaining TKA.Cite this article: EFORT Open Rev 2019;4:519-524. DOI: 10.1302/2058-5241.4.180083

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Over-constrained kinematic of the medial compartment leads to lower clinical outcomes after total knee arthroplasty

Knee Surgery Sports Traumatology Arthroscopy ◽

10.1007/s00167-020-06398-3 ◽

2021 ◽

Author(s):

Nicola Pizza ◽

Stefano Di Paolo ◽

Raffaele Zinno ◽

Giulio Maria Marcheggiani Muccioli ◽

Piero Agostinone ◽

...

Keyword(s):

Total Knee Arthroplasty ◽

Clinical Outcomes ◽

Knee Arthroplasty ◽

Motor Task ◽

Medial Compartment ◽

Level Of Evidence ◽

Contact Points ◽

Sit To Stand ◽

Medial Pivot ◽

Total Knee

Abstract Purpose To investigate if postoperative clinical outcomes correlate with specific kinematic patterns after total knee arthroplasty (TKA) surgery. The hypothesis was that the group of patients with higher clinical outcomes would have shown postoperative medial pivot kinematics, while the group of patients with lower clinical outcomes would have not. Methods 52 patients undergoing TKA surgery were prospectively evaluated at least a year of follow-up (13.5 ± 6.8 months) through clinical and functional Knee Society Score (KSS), and kinematically through dynamic radiostereometric analysis (RSA) during a sit-to-stand motor task. Patients received posterior-stabilized TKA design. Based on the result of the KSS, patients were divided into two groups: “KSS > 70 group”, patients with a good-to-excellent score (93.1 ± 6.8 points, n = 44); “KSS < 70 group”, patients with a fair-to-poor score (53.3 ± 18.3 points, n = 8). The anteroposterior (AP) low point (lowest femorotibial contact points) translation of medial and lateral femoral compartments was compared through Student’s t test (p < 0.05). Results Low point AP translation of the medial compartment was significantly lower (p < 0.05) than the lateral one in both the KSS > 70 (6.1 mm ± 4.4 mm vs 10.7 mm ± 4.6 mm) and the KSS < 70 groups (2.7 mm ± 3.5 mm vs 11.0 mm ± 5.6 mm). Furthermore, the AP translation of the lateral femoral compartment was not significantly different (p > 0.05) between the two groups, while the AP translation of the medial femoral compartment was significantly higher for the KSS > 70 group (p = 0.0442). Conclusion In the group of patients with a postoperative KSS < 70, the medial compartment translation was almost one-fourth of the lateral one. Surgeons should be aware that an over-constrained kinematic of the medial compartment might lead to lower clinical outcomes. Level of evidence II.

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Does a Modified Gap-balancing Technique Result in Medial-pivot Knee Kinematics in Cruciate-retaining Total Knee Arthroplasty?: A Pilot Study

Clinical Orthopaedics and Related Research ◽

10.1007/s11999-011-2121-6 ◽

2011 ◽

Vol 470 (1) ◽

pp. 91-98 ◽

Cited By ~ 25

Author(s):

Wolfgang Fitz ◽

Sonal Sodha ◽

William Reichmann ◽

Tom Minas

Keyword(s):

Total Knee Arthroplasty ◽

Pilot Study ◽

Knee Arthroplasty ◽

Knee Kinematics ◽

Cruciate Retaining ◽

Gap Balancing ◽

Medial Pivot ◽

Total Knee

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A Comparison of Stability and Clinical Outcomes in Single-Radius Versus Multi-Radius Femoral Design for Total Knee Arthroplasty

The Journal of Arthroplasty ◽

10.1016/j.arth.2014.03.033 ◽

2014 ◽

Vol 29 (12) ◽

pp. 2402-2406 ◽

Cited By ~ 19

Author(s):

Ah-Reum Jo ◽

Eun-Kyoo Song ◽

Keun-Bae Lee ◽

Hyoung-Yeon Seo ◽

Sung-Kyu Kim ◽

...

Keyword(s):

Total Knee Arthroplasty ◽

Clinical Outcomes ◽

Knee Arthroplasty ◽

Total Knee ◽

Single Radius

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Partial restoration of knee kinematics in severe valgus deformity using the medial-pivot total knee arthroplasty

Knee Surgery Sports Traumatology Arthroscopy ◽

10.1007/s00167-012-2315-9 ◽

2012 ◽

Vol 22 (7) ◽

pp. 1599-1606 ◽

Cited By ~ 8

Author(s):

Atsushi Kitagawa ◽

Kazunari Ishida ◽

Takaaki Chin ◽

Nobuhiro Tsumura ◽

Tetsushiro Iguchi

Keyword(s):

Total Knee Arthroplasty ◽

Knee Arthroplasty ◽

Knee Kinematics ◽

Valgus Deformity ◽

Partial Restoration ◽

Medial Pivot ◽

Total Knee

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Evaluation of Knee Kinematics in Single Radius versus Multi-Radii Total Knee Arthroplasty in India Population : A Randomized Control Trial

Open Access Journal of Biomedical Engineering and Biosciences ◽

10.32474/oajbeb.2018.01.000112 ◽

2018 ◽

Vol 1 (3) ◽

Author(s):

Ankur Sharma

Keyword(s):

Total Knee Arthroplasty ◽

Knee Arthroplasty ◽

Randomized Control Trial ◽

Knee Kinematics ◽

Total Knee ◽

Randomized Control ◽

Single Radius

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Comparison of Clinical Outcomes Between Total Knee Arthroplasties Using Medial-Pivot and Posterior-Stabilized Prosthesis: Minimum 8-year Follow-up Results in Chinese population

10.21203/rs.3.rs-18309/v1 ◽

2020 ◽

Author(s):

Zheng-yu Gao ◽

Cui-cui Guo ◽

Zi-an Zhang ◽

Guang-qian Shang ◽

Wei-ning Yan ◽

...

Keyword(s):

Total Knee Arthroplasty ◽

Survival Rate ◽

Range Of Motion ◽

Clinical Outcomes ◽

Knee Arthroplasty ◽

Womac Index ◽

Prosthesis Survival ◽

Medial Pivot ◽

Total Knee

Abstract Objective To compare the clinical outcomes of Medial-pivot and Posterior-stablized total knee arthroplasty during 8 years follow-up. Methods 109 patients with osteoarthritis who underwent primary total knee arthroplasty were conducted and divided into two groups according to the choice of prosthesis,49 in the Medial-pivot(MP) group and 60 in the Postirior-stabilized(PS) group.There were no statistical differences in age,gender,BMI,operative side and operation time between the two groups (P>0.05).The same protocol of perioperative treatment was adopted in both groups. Comparison of clinical outcome and survival rates were acquired through minimum 8 years follow-up. Results The prosthesis survival rate andthe excellent and good rate of MP group were 93.9% and 88.9% during average 8.3 years follow-up period,versus the prosthesis survival rate and the excellent or good rate of PS group were 93.3% and 86.7% during average 8.4 years follow-up period.There were no statistical diferences in survival rate,excellent and good rate and radiolucency of weight-bearing areas between the two groups ( P >0.05). There were no statistical differences in range of motion,KSS score and WOMAC index between the two groups preoperatively (P>0.05).The range of motion at all follow-up time points and KSS score at 6 months postoperatively of PS group were superior than those of MP group ( P <0.05),while the WOMAC index at 8 years postoperatively and Kujala scores at 1year and 8 years postoperatively of PS group were better than those of MP group( P <0.05). Conclusion Either medial-pivot or post-stabilized total knee arthroplasty could obtain excellent or good mid-term clinical result. Although with less range of motion, the patients using MP prosthesis could obtain better results in bone loss, performance of the patellofemoral joint and mid-term satisfaction. However, the use of MP prosthesis required more professional and precise technology and it should be cautious when using for knees with severe valgus deformation.

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Comparison of Knee Kinematics and Kinetics during Stair Ascent in Single-Radius and Multiradius Total Knee Arthroplasty

The Journal of Knee Surgery ◽

10.1055/s-0038-1669952 ◽

2018 ◽

Vol 32 (09) ◽

pp. 872-878 ◽

Cited By ~ 2

Author(s):

Bonnie Sumner ◽

John D. McCamley ◽

David J. Jacofsky ◽

Marc C. Jacofsky

Keyword(s):

Total Knee Arthroplasty ◽

Knee Arthroplasty ◽

Knee Kinematics ◽

Power Production ◽

Healthy Controls ◽

Stair Ascent ◽

Total Knee ◽

Kinetics Of ◽

Kinematics And Kinetics ◽

Single Radius

AbstractTraditionally total knee arthroplasty (TKA) design has been based on theories of the movement of the healthy knee joint. Currently, there are two competing theories on the flexion/extension axis of rotation of the knee with disparate radii of rotation, and thus differing movement patterns. The purpose of our study was to compare stair ascent kinematics and kinetics of single-radius (SR) and multiradius (MR) TKA subjects. We hypothesized that the knee kinematics and kinetics of SR TKA patients would more closely replicate healthy age matched controls during stair ascent than MR TKA patients, 1 year after TKA. Both patient groups had large improvements in biomechanical and clinical outcome measures following surgical intervention. However, the SR knee design performs closer to healthy controls than MR knees during stair ascent, supporting results that have been previously obtained for level walking. SR TKA subjects demonstrated reduced power production and sagittal moment compared with controls, albeit more than MR TKA subjects. This study demonstrates that patients who receive SR TKA have kinematics more closely aligned to normal patterns postoperatively than those who received an MR TKA. The power production and sagittal moment of the healthy controls most closely match previously published values of younger adults, SR TKA group most closely matches older adults, while the MR TKA group has lower power production and sagittal moments than either previously published age group. This strongly suggests that the biomechanical differences found in this study are evidence of functional deficiencies. Further research is needed to determine how these deficiencies progress with patient aging.

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