MicroPort’s Kinematic Alignment (KA) technique, when combined with the Evolution® Medial-Pivot Knee System’s implant design, offers surgeons an innovative solution to problems such as instability, anterior knee pain, and functional limitations. By utilizing traditional mechanical instruments and the “Measure Twice, Cut Once” methodology, surgeons can personalize each total knee replacement case to the individual patient’s joint line and restore their native knee anatomy based on the pre-diseased state. 

The Kinematic Alignment technique prioritizes the femoral cuts and compensates for wear on the femur to attain the pre-arthritic joint line. When the Evolution® Medial-Pivot Knee is positioned using Kinematic Alignment, each of the core knee axes are addressed, resulting in ligament isometry and balance without disrupting the patient’s ligaments.

Mechanical Alignment vs Kinematic Alignment 

Mechanical Alignment: Different Pre-Operative Conditions, Same Approach 

The traditional Mechanical Alignment (MA) technique provides a standardized method for surgeons to insert a knee implant for each patient using a series of non-anatomic cuts that do not account for the patient’s pre-arthritic joint line. Neutral tibial cuts are made independent of the femur, which may result in ligament releases to accommodate the implant in order to achieve a balanced knee. However, this approach precisely fits approximately 2.2% of the patient population.1  

The Kinematic Alignment technique seeks to provide an alternative alignment method that addresses the 20% of knee replacement patients that remain unsatisfied.2 Kinematic Alignment can personalize each total knee replacement to each patient by recreating their pre-diseased joint line and kinematics. Modern day implant designs and materials have enabled more physiological matching through implant motion and alignment. Kinematic Alignment places the implant in the patient’s physiologic position without disrupting the patient’s ligaments. 

5 Clinical Reasons to Combine Evolution® and Kinematic Alignment 

 

  1. Kinematic Alignment total knees restore function without placing the components at a high risk of failure.3 

  1. By restoring normal anatomic ligament balance, satisfaction rates significantly jump to 92.4%4 

  1. No difference in complication rate between Kinematic and Mechanical Alignment total knees for patients with mild preoperative deformities5 

  1. Kinematic Alignment has shown better outcomes than Mechanical Alignment in standard and combined Knee Society Scores, WOMAC scores, and knee flexion at short-term follow-up6 

  1. Treatment of patients with Kinematic Alignment was shown not to adversely affect the 10-year implant survival, yearly revision rate, and level of function7 

  • References
    1. Cherian, J. J., Kapadia, B. H., Banerjee, S., Jauregui, J. J., Issa, K., & Mont, M. A. (2014). Mechanical, anatomical, and kinematic axis in TKA: concepts and practical applications. Current reviews in musculoskeletal medicine, 7(2), 89-95. 

    1. Bourne, R. B., Chesworth, B. M., Davis, A. M., Mahomed, N. N., & Charron, K. D. (2010). Patient satisfaction after total knee arthroplasty: who is satisfied and who is not?. Clinical Orthopaedics and Related Research®, 468(1), 57-63. 

    1. Howell, S. M., Howell, S. J., Kuznik, K. T., Cohen, J., & Hull, M. L. (2013). Does a kinematically aligned total knee arthroplasty restore function without failure regardless of alignment category?. Clinical Orthopaedics and Related Research®, 471(3), 1000-1007. 

    1. Firer, P., & Gelbart, B. (2014, December). SUPERIOR PATIENT SATISFACTION AFTER TKA BY USING “IDEAL ARTHROPLASTY KINEMATICS”. In Orthopaedic Proceedings (Vol. 96, No. SUPP_19, pp. 32-32). The British Editorial Society of Bone & Joint Surgery. 

    1. Courtney, P. M., & Lee, G. C. (2017). Early outcomes of kinematic alignment in primary total knee arthroplasty: a meta-analysis of the literature. The Journal of arthroplasty, 32(6), 2028-2032. 

    1. Gao, Z. X., Long, N. J., Zhang, S. Y., Yu, W., Dai, Y. X., & Xiao, C. (2020). Comparison of Kinematic Alignment and Mechanical Alignment in Total Knee Arthroplasty: A Meta‐analysis of Randomized Controlled Clinical Trials. Orthopaedic Surgery. 

    1. Howell, S. M., Shelton, T. J., & Hull, M. L. (2018). Implant survival and function ten years after kinematically aligned total knee arthroplasty. The Journal of arthroplasty, 33(12), 3678-3684. 

Precautions and Disclaimers

Every patient is different, and individual results will vary. There are risks and recovery times associated with surgery.

Not all products and options are available in all countries.