Activities of daily living in non-Western cultures: range of motion requirements for hip and knee joint implants.

The purpose of this review of the literature was to investigate the functional range of motion requirements of non-Western populations in respect to artificial hip and knee joint implants. It was discovered that in Asia and the Middle East many activities are performed while squatting, kneeling, or sitting cross-legged. These positions demand a greater range of motion than that typically required in Western populations. For example, authors report that to squat one requires 130 degrees-full hip flexion and 111 degrees-165 degrees (or full) knee flexion. To sit cross-legged one requires 90 degrees-100 degrees hip flexion and 111 degrees-165 degrees (or full) knee flexion. This study identified a lack of documented research in this area, and the research that has been done provided inconsistent data. Potential reasons for discrepancies in the data are discussed, including the use of different methods to collect range of motion measurements, unclear use of terminology, and variations in normal passive and active range. In conclusion, this study stresses the importance of culture and function in the design and use of any new joint or product.