Objective(s): The objective of this study was to document and explain bilateral differences in the Q angle in adult Kashmiri population.

Materials and Methods: Four hundred limbs of healthy adult Kashmiri volunteers were studied. The Q angle was measured with a goniometer with the subjects supine, quadriceps relaxed and lower limbs in neutral rotation. The position of the tibial tuberosity with respect to the centre of the patella was measured. Appropriate statistical tests have been used in this study to determine the bilateral variability in the Q angle and lateral placement of tibial tuberosity in the adult population. Inter-observer variation parameters mentioned above were studied in fifty limbs.

Results: The average value of Q angle of all the 200 limbs was 12.73 °C; the mean value on the right being 12.86 °C and 12.60 °C on the left. A significant difference was noted in males when the Q angle and the lateral placement of the tibial tuberosity were considered in pairs. The Q angle value on the right side was quite often greater than the left. The relative position of the tibial tuberosity showed a significant positive correlation with the Q angle. The correlation coefficient was 0.66 for the Q angle and 0.8 for the lateral placement of the tibial tuberosity.

Conclusion: The present study shows that bilateral variability in the Q angle could be attributed to an alteration of the relative lateral placement of the tibial tuberosity with respect to the centre of the patella.

Keywords: Bilateral variability, Q angle, Tibial tuberosity.

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Dr Wajahat Ahmad Mir

Postgraduate Student, Dept of Orthopedics SKIMS MCH Bemina, India