From the Guidelines
No, you cannot use a Left Attune femoral posterior stabilized size 4 cemented component in a right knee. Femoral components are specifically designed for either the left or right knee, with anatomical differences that make them side-specific. Using a left-sided component in a right knee would result in improper fit, incorrect rotational alignment, and abnormal patellar tracking. This mismatch could lead to premature implant failure, instability, pain, and potentially require revision surgery, as seen in cases of aseptic loosening, which is a common cause of TKA failure 1. The asymmetrical design of modern knee implants accounts for the natural differences between left and right knee anatomy, particularly in the trochlear groove where the patella articulates.
Key Considerations
- Improper fit and incorrect rotational alignment can lead to instability, which is a significant cause of TKA failure, accounting for 7.5% of all cases 1
- Abnormal patellar tracking can result in pain, swelling, and acute synovitis, ultimately affecting patient outcomes and satisfaction rates, which range from 75% to 89% 1
- Using the correctly designated right-sided femoral component for a right knee replacement is crucial to ensure proper biomechanics and optimal patient outcomes, reducing the risk of revision surgery and long-term complications 1
Clinical Implications
- The growth in the number of primary TKA procedures has been accompanied by increased rates of TKA revision procedures, with loosening and infection being the most common failure mechanisms 1
- Identifying the cause of a painful TKA before surgery is critically important, as reoperation without a clear diagnosis can lead to suboptimal results 1
- Proper component selection and implantation technique are essential to minimize the risk of complications and ensure optimal patient outcomes, highlighting the importance of using the correct component for the right knee 1
From the Research
Implant Compatibility
- The provided studies do not directly address the compatibility of using a Left Attune femoral posterior stabilized size 4 cemented in a right knee.
- However, the studies discuss various aspects of total knee arthroplasty (TKA) and implant fixation, which may be relevant to the question of implant compatibility.
Implant Fixation
- A study on the distribution of implant fixation for femoral components of TKA found that minimal fixation seems necessary for long-term success of TKA femoral components 2.
- Another study compared the clinical and radiological results of a classic cemented fixed-bearing posterior-stabilized (PS) TKA system with its newer design, and found no significant differences in overall clinical scores, but a decrease in postoperative anterior knee pain and increased flexion in the newer design 3.
Cemented vs Uncemented Implants
- A study on the pattern of migration and clinical results of uncemented versus cemented fixation of the femoral component in TKA found that uncemented fixation works equally well as cemented fixation up to 10 years 4.
- Another study compared the revision rates of cemented Oxford Unicompartmental Knee Replacements with Single and Twin Peg femoral components, and found that the Twin Peg design had a lower revision rate due to decreased femoral loosening and pain 5.
Implant Design and Materials
- A study on the in vitro comparison of ceramic and metal cemented femoral components found no remarkable difference between the two materials in terms of mechanical loosening 6.