Essay On Joint Stability

Joint stability can be defined as control of the alignment of the joint segments and its angular position along an intended pathway, within the normal limits of the joint’s movement freedom (1-3). This ability is the sum of the contributions that passive and active joint components make to stability in typical daily living tasks. Dynamic joint stiffness (DJS) is the method usually used to study joint stability, as it serves as a joint stability indicator (1, 3). DJS is defined as the resistance offered by muscles and other joint structures to displacement of joint segments, and as a reaction to the external moment of force (1). The behaviour of joint moments and angles relations (4-6) can be used to assess DJS. Kinetic-kinematic analysis of DJS allows observations of the spring-like behaviour of the joint and the

Invitations included a description of the purpose of the study and procedures used and subjects provided informed consent in accordance with Helsinki Declaration. Subjects were sent an online version of the Lateral Performance Inventory (LPI) (16) to complete, online questionnaires have proved to be reliable (19), so we chose to use an online version to allow us to increase the sample size. A total of 164 subjects completed the LPI and a sample of 32 of these was selected for laboratory-based performance assessments on the basis of the following criteria: age between 18 and 40 years, with no history of ankle injury that might affect the outcomes. We deliberately selected a sample containing as many left-footed or ambidextrous subjects as possible. The sample was made up of 21 females (mean age = 23.0 years ± 2.98) and 11 males (mean age 23.64 years ± 2.25). Footedness distribution was 80.95% right-footed, 14.29% left-footed and 4.76% ambidextrous in the female subjects and 72.73% right-footed and 27.27% left-footed in the male subjects. Footedness scores were calculated in accordance with LPI instructions