title: Bilateral Variability of the Quadriceps Angle (Q angle) in an Adult Indian Population.
abstract: OBJECTIVE
  The objective of this study was to document and explain bilateral differences in the Q angle.
  
  
  METHODS
  Two hundred limbs of healthy adult Indian volunteers were studied. The Q angle was measured using a goniometric method with the subjects supine, quadriceps relaxed and lower limbs in neutral rotation. The relative lateral placement of the tibial tuberosity with respect to the centre of the patella was measured. Appropriate statistical tests were used to determine the bilateral variability in the Q angle and the lateral placement of the tibial tuberosity. Inter-observer variation of the above mentioned parameters were studied in twenty limbs.
  
  
  RESULTS
  The average Q angle value of all the 200 limbs was 12.73 °C; the mean value on the right was 12.86 °C and 12.60 °C on the left. When the Q angle and the lateral placement of the tibial tuberosity were considered in pairs a significant difference was noted in males. The Q angle value on the right side was more often greater than the left. The relative lateral placement of the tibial tuberosity showed a significant positive correlation with the Q angle. The intra-class correlation coefficient was 0.66 for the Q angle and 0.8 for the lateral placement of the tibial tuberosity.
  
  
  CONCLUSIONS
  The present study shows that bilateral variability in the Q angle could be attributed to an alteration of the relative placement of the tibial tuberosity with respect to the centre of the patella.
authors.affiliation: Department of Anatomy, Sri Manakula Vinayakar Medical College, Pondicherry, India.
authors.forename: Raveendranath
authors.initials: R
authors.lastname: Raveendranath
authors.forename: Shankar
authors.initials: S
authors.lastname: Nachiket
authors.forename: Narayanan
authors.initials: N
authors.lastname: Sujatha
authors.forename: Ranganath
authors.initials: R
authors.lastname: Priya
authors.forename: Devi
authors.initials: D
authors.lastname: Rema
keywords: Bilateral variability; Q angle; Tibial tuberosity