Evaluation of Anthropometric Measurements of the Aspect Ratio of Knee in Indian Population and its Correlation with the Sizing of Current Knee Arthroplasty System.

Background: Most of the commercially available TKR implants are designed for western populations, which are known to have larger build and stature compared to Asian counterparts often leading to mismatch between resected bony surfaces and implant components. There is paucity of morphometric data of distal femur and proximal tibia in the Indian population. Thus, it becomes important to obtain anthropometric data to achieve the best stability and long-term success of implant. Materials and Methods: Intraoperative morphological measurements of 100 knees (59 female and 41 males) were done using vernier calliper during TKR. The anteroposterior (AP) and mediolateral (ML) dimensions of cross-section of the femur and tibia were noted before bony resection. The aspect ratios were calculated and compared with that of implant used (DePuy, Stryker, Maxx). Results: We have found that Indian males have larger dimensions of distal femur as well as proximal tibia than females. There exists some degree of mismatch in patients' dimensions and the sizes of all the three commercially available implant system as well their aspect ratios. Conclusion: Specific designing of implants with dimensions in accordance with the morphometric measurements of Indian population should be done. Also gender specific implant designing should be done.