Relationship of Anterior Knee Pain with Quadriceps Angle and Anthropometric Measurements in an Asian Female Population

INTRODUCTION: Quadriceps angle (Q-angle) is the angle formed from the intersection of quadriceps femoris muscle and patellar tendon. Q-angle can be used to assess mechanical aspects of the patellofemoral discomfort and attracts considerable attention from clinicians. Anterior knee pain (AKP) is defined as mild pain localised around the peripatellar area exacerbated by physical activity such as climbing stairs, squatting, jumping, running, and/or sitting with the knee flexed for long periods. A higher Q-angle is one of the risk factors for AKP. In addition, several studies have found a relationship between anthropometric parameters, especially body mass index (BMI), to the occurrence of AKP. This study aims to determine the Q-angle and several anthropometric parameters between the population with AKP and without AKP in the adult population in Indonesia. MATERIALS AND METHODS: This cross-sectional, analytic experimental study was performed on female population divided into the comparison group consisted of 40 patients aged between 18-25 years with right side anterior knee pain (Kujala score <82) and the control group consisted of 40 patients aged between 18-25 years without anterior knee pain (Kujala score >82). Both groups had to be right-handed and had no history of knee fractures, knee surgery, congenital anomalies, or obesity. The Q-angle of the right knee was measured in all participants using a universal goniometer. RESULTS: The mean Q-angle in the comparison group was 20.60±1.26°, and in the control group was 14.85±0.99°. All of these differences were statistically significant (p<0.001). There was no significant correlation between anthropometric parameters (body weight, body height, and body mass index) with AKP. CONCLUSION: The Q-angle can be used to predict the risk of AKP in the female population. The greater the Q-angle the higher the risk of AKP. Anthropometric measurements cannot predict the risk of AKP.