Open versus Closed Kinetic Chain Rehabilitation of the Lower Extremity: A Functional and Biomechanical Analysis

Closed kinetic chain and functional rehabilitation have lately received increased attention in the rehabilitation community. The purpose of this paper is to review biomechanical considerations applicable to the lower extremity, in a way that clearly justifies the use of functionally sound rehabilitation exercises. The origin of the kinetic chain concept is reviewed, and the differences in biomechanical events in the foot, ankle, and knee under open versus closed chain conditions are described. An analysis of these biomechanical events supports the notion that function results from the integration of muscles and joints to achieve desired outcomes. This leads to the conclusion that rehabilitation exercises, in order to be functional, must demand integration of muscular activity, must be of a closed kinetic chain nature, and must challenge the utilization of normal proprioceptive mechanisms. Guidelines for the practical application of these principles are clearly outlined, and examples of functional activiti...