The objective of this chapter is to present an overview of clinical gait analysis (GA). GA is a process of instrumental measurement and evaluation of walking ability in patients with specific problems related to locomotion. This analysis is intended to provide answers to specific clinical questions, which in turn affects future clinical decisions and monitoring of the patient. GA is often conducted in a laboratory setting by clinicians with subspecialty training; its goal is also to aid in functional restoration.
Cerebral palsy represents an example of a disease state in which clinical GA has provided advanced management strategies that substantially affected functional restoration. An accreditation in GA helps to ensure that quality standards are met. Most common measures taken during GA include time–distance parameters; kinematics of body segments and joints; kinetics, an analysis of the forces that come into play during motion; muscular performance; and energy consumption. Generally, data obtained are summarized in a clinical report, including their biomechanical and clinical interpretation and treatment recommendations.1
Gait is the most important method of human locomotion characterized by periods of loading and unloading of the limbs to facilitate movement and function. Such movement affects many other functional activities such as performance of activities of daily living (ADLs), involvement in social activities, and his participation in a vocation/occupation.
GA consists of an analysis of joint kinematics, kinetics, and dynamic electromyography (EMG) data. The analysis is performed and properly interpreted by experienced individuals and improves basic knowledge regarding an individual's physiological and pathological gait function.
An accurate understanding of appropriate terminology in the analysis of gait movements is of great importance. Different biomechanical and muscular variables are often studied and many of them are highly interrelated.2 Clarity regarding the method by which measures are acquired and calculated, units of measurement used and the normalization of standards is critical. Only an accurate and systematic approach to “data handling” will permit the assessment of the efficiency of the instruments and methodologies of acquisition and evaluation.3
One must understand the normal gait cycle prior to completely understanding complex pathology.1,3–9
The “gait cycle” is defined as the set of moments and events that take place between two successive initial contacts of the ground with the same foot. It can be divided into two principal phases: the “stance phase,” during which the foot remains in contact with the ground, and the “swing phase,” during which the foot is brought forward. In normal subjects, the cycle begins with a heel-strike (0%), and terminates with another heel-strike of the same foot (100%). When a person is walking at normal speed, the stance phase typically constitutes about 61% of the entire cycle, and the swing phase takes up 39%; the various events ...