Clinical implications of anthropometric patellar dimensions for TKA in Asians

Anthropometric patellar dimensions can influence implant design and surgical techniques in patellar resurfacing for TKA. We measured anthropometric patellar dimensions in 752 osteoarthritic knees (713 in females and 39 in males) treated with TKA in 466 Korean patients and compared them with reported dimensions for Western patients. We investigated the effects of postoperative overall thickness deviations, residual bony thickness after bone resection, and postoperative deviations of component center positions from median ridge positions versus clinical and radiographic outcomes evaluated 1 year after surgery. Korean patients undergoing TKA had thinner and smaller patellae than Western patients. We found no associations between preoperative to postoperative overall thickness differences and clinical and radiographic outcomes and no differences between knees with a residual bony thickness 12 mm or greater and knees with a residual thickness less than 12 mm, with the exception of WOMAC pain scores. We found no associations between postoperative deviations of component center position and clinical or radiographic outcomes. Our findings indicate bone resection for patellar resurfacing can be flexible without jeopardizing clinical outcome. LEVEL OF EVIDENCE: Level IV, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence