Background: The physiological cost index (PCI) was established by McGregor (1979) to quantify the energy expenditure associated with walking. The difference between walking and resting heart rates divided by walking pace is known as the physiological cost index. Traumatic below-knee amputees typically use 25% more energy overall when walking than average people. Amputees need more energy when walking than persons in good health, which is one of their most noticeable issues. For example, walking with a transtibial prosthesis raises the body's energy requirements by up to 30 %. The aim of study was to compare physiological cost index among transtibial amputee and normal individual.

Methodology: An observational study was carried out at Jaipur Foot Centre, Ahmedabad. In order to evaluate conformity with inclusion and exclusion criteria, the subject is first examined. A total of 36 subjects, both male and female, were included in the study and split into two groups. According to the inclusion criteria, Group 1 consists of 18 transtibial amputees wearing exoskeleton prostheses, while Group 2 consists of 18 normal persons. For both normal individuals and transtibial amputees, the physiological cost index (PCI) was calculated.

Results: According to the study findings, the amputee group shows higher physiological cost index (PCI) value than that of normal people. The mean PCI value for amputees is 0.6±0.2, which is greater than the mean PCI value for normal individuals, which is 0.3±0.1. This indicates that amputees have a higher physiological cost index.