Morphological study of linea aspera variations - proposal of classification and sexual dimorphism.

The linea aspera is a roughened, longitudinally-oriented irregular crest composed of two lips located on the posterior surface of the femoral shaft. The purpose of this research was to investigate the morphological variations of the linea aspera in humans. The study was carried out on 90 femurs. Osteometric measurements of the bones were taken using two complementary methods: classical osteometry and a new one based on the analysis of digital photographic documentation of the femur using MultiScanBase v.18.03 software. The analysis allowed four types of the linea aspera to be determined: parallel (type I - 27.2%), concave (type II - 25.7%), convex (type III - 5.7%) and variform (type IV - 41.4%). The frequency of the each type in female and male was also described. Better knowledge of the anatomical variations of the linea aspera may be helpful in Orthopaedy and Radiology to distinguish pathological from normal anatomical variations.