THE HIP STRESS LEVEL ANALYSIS FOR HUMAN ROUTINE ACTIVITIES+

Since 1980' s, Bergmann and his research group have been pursuing the instrumented hip implants with telemetric data transmission [1-6]. Their collected gait data were recorded in HIP98[7], and it was updated in 2001. So far it is unique gait data base of the human hip contact force simultaneously measured in vivo. It is well recognized, however, that intrinsic pathomechanical changes in articulator cartilage depends upon local stress levels rather than upon global joint loading, and the abnormal mechanical stress upon hip joint cartilage is one of the main causes of osteoarthritis. In this paper, therefore, based on the gait data of HIP98 (2001 version) and Hertzian elasticity contact theory, a realistic stress level and peak stress analysis at hip joint for the human routine activities are presented.