Geometric analysis of medio-lateral position of patella: a new measuring tool.

BACKGROUND Evaluation of medio-lateral position of patella is necessary for diagnosis and treatment of patellofemoral diseases. OBJECTIVE In the present study, we aimed to evaluate medio-lateral patellar position differences and to define a new practical measuring tool which enables us to analyze relationships of the points at the knee. MATERIALS AND METHODS Total of 120 healthy volunteers (60 men and 60 women) were included in our study and both of their knees were measured. In the research, the gender groups and right-left differences were evaluated. In the measurements, a four-lever measuring tool designed for this study was used. The four anatomic points of the knee which are center of patella, epicondylus lateralis, epicondylus medialis and middle point of tuberositas tibiae were used. RESULTS While patella is 76% lateral in the right knee, it is 90% lateral in the left knee in men. As for woman, while it is 50% lateral in the right-knee, it is 30% lateral in the left-knee. In medio-lateral patellar position, while bilateral asymmetry is 28% in men, it is 50% in women. In measurements of knees of women and men, significant differences were detected both in the right and left knees ( P < 0.05 and P < 0.001). CONCLUSION The patellofemoral order differences between men and women can explain anatomic reasons of patellofemoral diseases, which are encountered more in women than men.