Biomechanics and wear comparison between mechanical and kinematic alignments in total knee arthroplasty

2018 ◽  
Vol 232 (12) ◽  
pp. 1209-1218 ◽  
Author(s):  
Zhenxian Chen ◽  
Yongchang Gao ◽  
Shibin Chen ◽  
Qida Zhang ◽  
Zhifeng Zhang ◽  
...  
Keyword(s):  
Total Knee Arthroplasty ◽  
Contact Force ◽  
Knee Arthroplasty ◽  
Kinematic Alignment ◽  
Wear Volume ◽  
Mechanical Alignment ◽  
Collateral Ligament ◽  
Cycle Simulation ◽  
Total Knee

The uses of mechanical and kinematic alignments in total knee arthroplasty are under debate in recent clinical investigations. In this study, the differences in short-term biomechanics and long-term wear volume between mechanical and kinematic alignments in total knee arthroplasty were investigated, based on a subject-specific musculoskeletal multi-body dynamics model during walking gait simulation. An increase of 8.2% in the peak tibiofemoral medial contact force, a posterior contact translation by maximum 4.7 mm and a decrease of 5.5% in the wear volume after a 10-million-cycle simulation were predicted in the kinematic alignment, compared with the mechanical alignment. Nevertheless, the tibiofemoral contact mechanics, the range of motions and the long-term wear were not markedly different between mechanical and kinematic alignments. Furthermore, the mechanical alignment with a posterior tibial slope similar to that under the kinematic alignment was found to produce similar anterior–posterior translation and the range of motion, and an approximate wear volume, compared with the kinematic alignment. The ligament forces under the kinematic alignment were influenced markedly by as much as 25%, 50% and 77% for the medial collateral ligament, lateral collateral ligament and posterior cruciate ligament forces, respectively. And, a maximum increase of 40% for patellofemoral contact force was predicted under the kinematic alignment. These findings suggest that the kinematic alignment is an alternative alignment principle but no marked advantages in biomechanics and wear to the mechanical alignment. The adverse effects of the kinematic alignment on patella loading and soft tissue forces should be noticed.

scholarly journals Anatomic Versus Mechanically Aligned Total Knee Arthroplasty for Unicompartmental Knee Arthroplasty Revision

2016 ◽  
Vol 10 (1) ◽  
pp. 357-363 ◽  
Author(s):  
Panagiota Toliopoulos ◽  
Marc-Andre LeBlanc ◽  
Jonathan Hutt ◽  
Martin Lavigne ◽  
Francois Desmeules ◽  
...  
Keyword(s):  
Total Knee Arthroplasty ◽  
Clinical Outcomes ◽  
Knee Arthroplasty ◽  
Womac Score ◽  
Kinematic Alignment ◽  
Mechanical Alignment ◽  
Medial Proximal Tibial Angle ◽  
Alignment Technique ◽  
Total Knee ◽  
Small Patient

Objectives:The purpose of this study was to compare the intra-operative benefits and the clinical outcomes from kinematic or mechanical alignment for total knee arthroplasty (TKA) in patients undergoing revision of failed unicompartmental kneel arthroplasty (UKA) to TKA.Methods:Ten revisions were performed with a kinematic alignment technique and 11 with a mechanical alignment. Measurements of the hip-knee-ankle angle (HKA), the lateral distal femoral angle (LDFA), and the medial proximal tibial angle (MPTA) were performed using long-leg radiographs. The need for augments, stems, and constrained inserts was compared between groups. Clinical outcomes were compared using the WOMAC score along with maximum distance walked as well as knee range of motion obtained prior to discharge. All data was obtained by a retrospective review of patient files.Results:The kinematic group required less augments, stems, and constrained inserts than the mechanical group and thinner polyethylene bearings. There were significant differences in the lateral distal femoral angle (LDFA) and the medial proximal tibial angle (MPTA) between the two groups (p<0.05). The mean WOMAC score obtained at discharge was better in the kinematic group as was mean knee flexion. At last follow up of 34 months for the kinematic group and 58 months for the mechanical group, no orthopedic complications or reoperations were recorded.Conclusion:Although this study has a small patient cohort, our results suggest that kinematic alignment for TKA after UKA revision is an attractive method. Further studies are warranted.

Patient satisfaction following total knee arthroplasty using restricted kinematic alignment

2021 ◽  
Vol 103-B (6 Supple A) ◽  
pp. 59-66
Author(s):  
Sarag Abhari ◽  
Thomas M. Hsing ◽  
Max M. Malkani ◽  
Austin F. Smith ◽  
Langan S. Smith ◽  
...  
Keyword(s):  
Total Knee Arthroplasty ◽  
Patient Satisfaction ◽  
Knee Arthroplasty ◽  
Varus Deformity ◽  
Advanced Technology ◽  
Kinematic Alignment ◽  
Mechanical Alignment ◽  
Entire Cohort ◽  
Total Knee

Aims Alternative alignment concepts, including kinematic and restricted kinematic, have been introduced to help improve clinical outcomes following total knee arthroplasty (TKA). The purpose of this study was to evaluate the clinical results, along with patient satisfaction, following TKA using the concept of restricted kinematic alignment. Methods A total of 121 consecutive TKAs performed between 11 February 2018 to 11 June 2019 with preoperative varus deformity were reviewed at minimum one-year follow-up. Three knees were excluded due to severe preoperative varus deformity greater than 15°, and a further three due to requiring revision surgery, leaving 109 patients and 115 knees to undergo primary TKA using the concept of restricted kinematic alignment with advanced technology. Patients were stratified into three groups based on the preoperative limb varus deformity: Group A with 1° to 5° varus (43 knees); Group B between 6° and 10° varus (56 knees); and Group C with varus greater than 10° (16 knees). This study group was compared with a matched cohort of 115 TKAs and 115 patients using a neutral mechanical alignment target with manual instruments performed from 24 October 2016 to 14 January 2019. Results Mean overall patient satisfaction for the entire cohort was 4.7 (SE 0.1) on a 5-point Likert scale, with 93% being either very satisfied or satisfied compared with a Likert of 4.3 and patient satisfaction of 81% in the mechanical alignment group (p < 0.001 and p < 0.006 respectively). At mean follow-up of 17 months (11 to 27), the mean overall Likert, Knee Injury and Osteoarthritis Outcome Score for Joint Replacement, Western Ontario and McMaster Universities Osteoarthritis Index, Forgotten Joint Score, and Knee Society Knee and Function Scores were significantly better in the kinematic group than in the neutral mechanical alignment group. The most common complication in both groups was contracture requiring manipulation under anaesthesia, involving seven knees (6.1%) in the kinematic group and nine knees (7.8%) in the mechanical alignment group. Conclusion With the advent of advanced technology, and the ability to obtain accurate bone cuts, the target limb alignment, and soft-tissue balance within millimetres, using a restricted kinematic alignment concept demonstrated excellent patient satisfaction following primary TKA. Longer-term analysis is required as to the durability of this method. Cite this article: Bone Joint J 2021;103-B(6 Supple A):59–66.

scholarly journals Restoring the constitutional alignment with a restrictive kinematic protocol improves quantitative soft-tissue balance in total knee arthroplasty: a randomized controlled trial

2020 ◽  
Vol 102-B (1) ◽  
pp. 117-124 ◽  
Author(s):  
Samuel J. MacDessi ◽  
William Griffiths-Jones ◽  
Darren B. Chen ◽  
Sam Griffiths-Jones ◽  
Jil A. Wood ◽  
...  
Keyword(s):  
Total Knee Arthroplasty ◽  
Knee Arthroplasty ◽  
Controlled Trial ◽  
Kinematic Alignment ◽  
Mechanical Alignment ◽  
Randomized Controlled ◽  
Superiority Trial ◽  
Total Knee ◽  
The Mean ◽  
Lift Off

Aims It is unknown whether kinematic alignment (KA) objectively improves knee balance in total knee arthroplasty (TKA), despite this being the biomechanical rationale for its use. This study aimed to determine whether restoring the constitutional alignment using a restrictive KA protocol resulted in better quantitative knee balance than mechanical alignment (MA). Methods We conducted a randomized superiority trial comparing patients undergoing TKA assigned to KA within a restrictive safe zone or MA. Optimal knee balance was defined as an intercompartmental pressure difference (ICPD) of 15 psi or less using a pressure sensor. The primary endpoint was the mean intraoperative ICPD at 10° of flexion prior to knee balancing. Secondary outcomes included balance at 45° and 90°, requirements for balancing procedures, and presence of tibiofemoral lift-off. Results A total of 63 patients (70 knees) were randomized to KA and 62 patients (68 knees) to MA. Mean ICPD at 10° flexion in the KA group was 11.7 psi (SD 13.1) compared with 32.0 psi in the MA group (SD 28.9), with a mean difference in ICPD between KA and MA of 20.3 psi (p < 0.001). Mean ICPD in the KA group was significantly lower than in the MA group at 45° and 90°, respectively (25.2 psi MA vs 14.8 psi KA, p = 0.004; 19.1 psi MA vs 11.7 psi KA, p < 0.002, respectively). Overall, participants in the KA group were more likely to achieve optimal knee balance (80% vs 35%; p < 0.001). Bone recuts to achieve knee balance were more likely to be required in the MA group (49% vs 9%; p < 0.001). More participants in the MA group had tibiofemoral lift-off (43% vs 13%; p < 0.001). Conclusion This study provides persuasive evidence that restoring the constitutional alignment with KA in TKA results in a statistically significant improvement in quantitative knee balance, and further supports this technique as a viable alternative to MA. Cite this article: Bone Joint J. 2020;102-B(1):117–124

Kinematic alignment is a possible alternative to mechanical alignment in total knee arthroplasty

2017 ◽  
Vol 25 (11) ◽  
pp. 3467-3479 ◽  
Author(s):  
Yong Seuk Lee ◽  
Stephen M. Howell ◽  
Ye-Yeon Won ◽  
O-Sung Lee ◽  
Seung Hoon Lee ◽  
...  
Keyword(s):  
Total Knee Arthroplasty ◽  
Knee Arthroplasty ◽  
Kinematic Alignment ◽  
Mechanical Alignment ◽  
Total Knee

scholarly journals Clinical outcomes of kinematic alignment versus mechanical alignment in total knee arthroplasty: a systematic review

2020 ◽  
Vol 5 (8) ◽  
pp. 486-497
Author(s):  
Mark Anthony Roussot ◽  
Georges Frederic Vles ◽  
Sam Oussedik
Keyword(s):  
Total Knee Arthroplasty ◽  
Soft Tissue ◽  
Clinical Outcomes ◽  
Knee Arthroplasty ◽  
Soft Tissue Balance ◽  
Kinematic Alignment ◽  
Mechanical Alignment ◽  
Patient Reported ◽  
Total Knee ◽  
Alignment Strategy

Although mechanical alignment (MA) has traditionally been considered the gold standard, the optimal alignment strategy for total knee arthroplasty (TKA) is still debated. Kinematic alignment (KA) aims to restore native alignment by respecting the three axes of rotation of the knee and thereby producing knee motion more akin to the native knee. Designer surgeon case series and case control studies have demonstrated excellent subjective and objective clinical outcomes as well as survivorship for KA TKA with up to 10 years follow up, but these results have not been reproduced in high-quality randomized clinical trials. Gait analyses have demonstrated differences in parameters such as knee adduction, extension and external rotation moments, the relevance of which needs further evaluation. Objective improvements in soft tissue balance using KA have not been shown to result in improvements in patient-reported outcomes measures. Technologies that permit accurate reproduction of implant positioning and objective measurement of soft tissue balance, such as robotic-assisted TKA and compartmental pressure sensors, may play an important role in improving our understanding of the optimum alignment strategy and implant position. Cite this article: EFORT Open Rev 2020;5:486-497. DOI: 10.1302/2058-5241.5.190093

scholarly journals Kinematic versus mechanical alignment for primary total knee arthroplasty with minimum 2 years follow-up: a systematic review

SICOT-J ◽  
2020 ◽  
Vol 6 ◽  
pp. 18 ◽  
Author(s):  
Elliot Sappey-Marinier ◽  
Adrien Pauvert ◽  
Cécile Batailler ◽  
John Swan ◽  
Laurence Cheze ◽  
...  
Keyword(s):  
Systematic Review ◽  
Total Knee Arthroplasty ◽  
Cohort Studies ◽  
Knee Arthroplasty ◽  
Primary Total Knee Arthroplasty ◽  
Kinematic Alignment ◽  
Mechanical Alignment ◽  
Significant Difference ◽  
Total Knee

Purpose: The aim of this study was to perform a systematic review of the literature to determine whether there are any clinical or radiological differences in mechanically aligned Total Knee Arthroplasty (TKA) compared with kinematically aligned TKA. Methods: This study included retrospective cohort studies, prospective randomized controlled trials (PRCTs) and prospective cohort studies comparing clinical and radiological outcomes, and complications in TKA with kinematic alignment (KA) and mechanical alignment (MA). All studies had a minimum follow-up of 2 years. Results: Five PRCTs published between 2014 and 2020 were included. These studies showed a low risk of bias and were of very high quality. We did not find a superiority of KA compared to MA technique for clinical and radiological outcomes, except in one study which showed a significant difference favoring KA between the two groups for all clinical scores. Conclusion: We found that KA in TKA achieved clinical and radiological results similar to those of MA. The complication rate was not increased for KA TKAs. Studies with longer follow-up and larger cohorts are required to prove any benefit of KA technique over MA technique.

scholarly journals Kinematic alignment is bone and soft tissue preserving compared to mechanical alignment in total knee arthroplasty

The Knee ◽  
2019 ◽  
Vol 26 (2) ◽  
pp. 466-476 ◽  
Author(s):  
Vincent V.G. An ◽  
Joshua Twiggs ◽  
Murilo Leie ◽  
Brett A. Fritsch
Keyword(s):  
Total Knee Arthroplasty ◽  
Soft Tissue ◽  
Knee Arthroplasty ◽  
Kinematic Alignment ◽  
Mechanical Alignment ◽  
Total Knee
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