Introduction: Although we recently reported a detailed description of wear pattern in Caucasians, few studies have investigated severity of wear, and pattern of wear on the patella and femur in Japanese. The purpose of this study was to determine if there is a common joint specific wear pattern in the patellofemoral joint of Japanese cadavers. We further compared the wear pattern and severity between Japanese and US cadavers.
Methods: We examined 46 patellae and matching femurs from 23 Japanese cadavers. The wear location was transcribed to gridded templates, that were compared for frequency, gender, and sidedness of wear.
Results: Over 60% of the patella showed wear in the odd facet, the middle part of the medial facet, and the medial aspect of the middle part of the lateral facet. The distal femur showed common areas of wear in the posterior aspect of the medial femoral condyle and anterior aspect of the medial femoral condyle. Patella wear may differ with gender as male's wear was more compact. Although the patella and femur wear area was similar between Japanese and US cadavers, femoral wear may be more severe in Japanese cadavers.
Discussion: Patella and femur showed distinct regions of articular cartilage wear. The wear patterns and locations suggest that wear occurs mainly when the knees are moderately and deeply flexed and that these wear patterns may result from common traditional Japanese style of knee positions or activities. (C) 2017 Anatomical Society of India. Published by Elsevier, a division of RELX India, Pvt. Ltd. All rights reserved.