Influence of Gender and Leg Dominance on Q-angle Among Young Adult Nigerians

The quadriceps femoris muscle angle (Q-angle) is a known index of knee function and patellofemoral kinetics. This study reports normal values of the Q-angle measured bilaterally in a sample of young adult Nigerians aged 17 - 30 years and the influence of leg dominance and gender on the Q-angle. Four hundred healthy volunteers (200 males and 200 females) with no history of musculoskeletal pathology that could influence the Q-angle participated in the study, using the non-probability sample of convenience. The Q-angle was measured using a universal goniometer with the subject in the erect weight-bearing position. Results showed that in the male subjects, the Q-angles were 12.30 ± 4.0E and 10.38 ± 3.49E for the right and left lower limbs respectively, while in the female subjects, the Q-angles were 17.06 ± 3.64E and 14.84 ± 3.47E for the right and left lower limbs respectively. Analysis revealed a significant contra-lateral difference. Generally, the right Q-angle was significantly higher than the left (p< 0.05) in both the male and female subjects. The females had significantly higher Q-angles than their male counterparts (p< 0.05). Leg dominance did not have a significant influence (p > 0.05), as the right Q-angle was higher than the left in subjects with right leg dominance as well as those with left leg dominance. From these results, the assumption that Q-angles in the right and left limbs are equal is contending, and it is therefore recommended that measures of Q-angles should be documented as either right or left in the clinics as well as in research reports. KEY WORDS: Q-angle, leg dominance, gender influence