Abstract
Background: Total knee replacement remains one of the most common knee surgery practices worldwide. The operative procedure universally requires the use of cutting jigs to resect predetermined amounts of bone irrespective of the preoperative anatomy and morphology of the femur and tibia.
Aims: The aims of this study were to elucidate anatomical morphological differences between ethnicities pre-operatively and to assess whether any change elucidated was preserved post-operatively.
Method: This was a retrospective study comparing the pre and postoperative lateral view X-Rays of TKRs performed. Distances measured from most prominent anterior point to midline and the most prominent posterior point to midline and their ratio was compared between two ethnic groups. Each x-ray measurement was triple checked.
Results: The study groups comprised of 60 Caucasian knees and 40 Asian knees. Preoperatively the mean ratio was 0.55 in Caucasians and 0.44 in Asians, with this difference being statistically significant (p value < 0.005). Post operatively the mean ratio was 0.59 in Caucasians and 0.55 in Asians and this difference was not statistically significant (p value =0.166). These findings were also cross-checked with range of movement measurements post-operatively in the same group of patients. There was no comparable improvement in range of movements (ROM) post-operatively in the Asian group.
Conclusion: We infer that the present TKR cutting jigs are not taking into account the anatomical differences within the knee of Asians individuals. This is converting the post operative distal femurs of this group to become morphologically comparable to the Caucasian knee and this is possibly affecting the kinematics of those knees leading to no significant improvement in the post operative ROM and affecting satisfaction with surgery.
Correspondence should be addressed to Mr T Wilton, c/o BOA, BASK at the Royal College of Surgeons, 35–43 Lincoln’s Inn Fields, London WC2A 3PE, England.
