[Sensorimotor Deficits in Functional Ankle Instability].
Steib S,Pfeifer K
Zeitschrift fur Orthopadie und Unfallchirurgie
Lateral ankle sprains are among the most common sports injuries, with a prevalence of 25 to 30 % of all injuries. At least one-third of individuals develop long-term complaints and chronic instabilities at the ankle, which in many cases cannot be attributed to mechanical insufficiencies of the joint. This condition is referred to as functional ankle instability (FAI). Impairments of the sensorimotor control system, such as disturbed proprioception and postural control, as well as reduced muscle strength and reflex activity, have been suggested to contribute to the aetiology of FAI. This review summarises the current body of literature regarding sensorimotor control in individuals with FAI. We discuss the results in the context of current neurophysiological models of the development of functional joint instabilities.
Ankle Joint Control in People with Chronic Ankle Instability During Run-and-cut Movements.
Fuerst Patrick,Gollhofer Albert,Lohrer Heinz,Gehring Dominic
International journal of sports medicine
Despite a considerable amount of research, the deficits causing recurrent sprains in people with chronic ankle instability are still unclear. Changes in frontal plane kinematics and decreased peroneal activation have been proposed as potential underlying mechanisms, but whether people with ankle instability show deficits in control of injury-relevant movements is not well understood. Therefore, the purpose of the present study was to analyse ankle joint kinematics and kinetics as well as neuromuscular activation during dynamic change-of-direction movements. Eighteen participants with functional instability, 18 participants with functional and mechanical instability and 18 healthy controls performed 45° sidestep-cutting and 180° turning movements in reaction to light signals. During sidestep-cutting both instability groups displayed significantly lower inversion angles than controls when the trials with the highest maximum inversion angle of each participant were compared. In turning movements, participants with functional instability presented significantly lower average maximum inversion angles than controls as well as higher peroneal activation before foot strike than participants with both functional and mechanical instability. We theorize that the observed changes in movement kinematics of participants with chronic ankle instability are the result of a protective strategy to limit frontal plane ankle joint loading in potentially harmful situations.
Correlation Between Joint-Position Sense, Peroneal Strength, Postural Control, and Functional Performance Ability in Patients With Chronic Lateral Ankle Instability.
Cho Byung-Ki,Park Ji-Kang
Foot & ankle international
BACKGROUND:The first aim of this study was to evaluate the side-to-side difference of joint-position sense, peroneal strength, postural control, and functional performance ability in patients with chronic lateral ankle instability. The second aim was to identify the correlation between various components contributing to the functional ankle instability (FAI). METHODS:Thirty-five patients to be scheduled for the modified Broström procedure for chronic ankle instability were analyzed. Joint-position sense and peroneal strength were measured with an isokinetic dynamometer. Postural control ability was evaluated using the modified Romberg test. The functional performance test consisted of the 1-leg hop test, 6-meter hop test, and cross 3-m hop test. Spearman's correlation coefficient () was calculated to determine the linear association between the individual components of the FAI. RESULTS:Except for the 6-m and cross 3-m hop tests, most examination tools for the FAI demonstrated significant side-to-side differences compared with the unaffected ankle. Spearman's correlation analysis revealed that individual components (joint-position sense, peroneal strength, postural control, and functional performance ability) of the FAI were significantly associated with one another, except between peroneal strength and postural control ability ( = 0.21, = .195). CONCLUSION:Joint-position sense, peroneal strength, postural control ability, and 1-leg hop test demonstrated significant side-to-side differences in patients with chronic lateral ankle instability. Individual components contributing to the FAI were significantly correlated with one another, except between peroneal strength and postural control ability. Postural control evaluation using the modified Romberg test could substitute for dynamometer testing, with convenience and economic advantage. LEVEL OF EVIDENCE:Level IV, prospective case series.