The Effect of the Height of the Asana Seat on Flexion Knee Angle and Monk's Satisfaction while Sitting in a Cross-legged Posture

Abstract

Background: Buddhist monks usually sit on the floor in a cross-legged posture. Deep flexion of knees more than 90-degree increases mechanical loads at the knee joint, which is one of the causes of osteoarthritis of the knee. The use of a higher asana seat may decrease flexion knee angle.  Objective: To find the proper height of the asana seat that decreases flexion knee angle and increases the satisfaction of the monk. Method: This was an experimental study of 50 Buddhist monks sitting on the asana seats at different heights of 5, 10, and 15 centimeters. Then the Buddhist monks were asked to answer the satisfaction questionnaire and did a knee X-ray to measure flexion knee angle. Result: While sitting on the 5 cm, 10 cm, and 15 cm height asana seats, the flexion knee angle was 129.2 ± 11.9, 128.4 ± 11.2, 126.8 ± 11.1, respectively. The difference in flexion knee angle was not statistically significant (p-value > 0.05). The satisfaction score on comfortability was 4.36 ± 0.75, 3.64 ± 1.06, 3.04 ± 1.5, and the satisfaction score on suitability was 4.28 ± 0.93, 3.32 ± 1.04, 2.56 ± 1.36, respectively. Both satisfaction scores of 5 cm height asana seat were higher than 10 cm and 15 cm height asana seats significantly (p-value < 0.05).  Conclusion: The most suitable height of the asana seat in this study is 5 centimeters, nearly the same height as the commonly used asana.