Effect of Kinesiotaping on Ankle Stability

Ankles sprains are the most popular injuries in basketball players. They are traumatic injuries, which happen most of the time in specific situations, like landing on another player's foot, or during changes of direction. Neuromuscular exercises are very important to improve ankle stability and reduce risks of sprains. However various external support such as ankles braces and rigid tape, are also used in order to prevent injury. The kinesiotape (KT) is a new but broadly used method in the world of athletes. Created by KenzoKase, in 1980, this kind of tape has a tremendous success with athletes and is today commonly used during practices and/or competitions. The main property of this tape is its elasticity, which is supposed to improve proprioception and, thus ankle stability, but these aspects have not been investigated yet.

Aim: Compare the effects of a kinesiotape (KT) with a sham treatment (KT put with no effects) and a control condition (absence of tape) in basketball players from the Swiss national league through balance tests on an unstable surface. Hypotheses: A KT positioned on the lateral side of the leg improves ankle stability in basketball players while balancing on an unstable surface. Method: 30 subjects will be recruited from different basketball teams affiliated to the Swiss national league. They will have to perform some postural stability tests on both unstable ("Delos") and stable surfaces ("Single Les Stance", "Star Excursion Balance Test", "Cross Over Hop Test for Distance") under three different conditions. The three condition will be as followed : with a KT positioned on the lateral side of the leg, with a sham tape or without tape. The three sessions will be spaced in time (7 days of wash out). The order of the three interventions (KT, Sham tape, no tape) will be randomized (cross over) to avoid the bias of learning processes. Neither the subjects nor the examiner will be aware of the "tape condition" (double blind); a physiotherapist will be in charge of positioning the tape according to the tested condition. The sequence of the tests will be the same for all subjects and breaks are scheduled to avoid the effect of the fatigue. An anamnesis of all subjects will be done in order to evaluate history of injuries. At the end of each session, a visual analogical scale will be completed by the athlete to obtain a personal feeling of stability . The subject will be also asked to determine which condition was tested. Expected results: the application of a KT on the lateral side of the leg improves postural stability on instable surfaces in elite basketball players. Field's importance: the application of KT may reduce the risk of ankle sprains and the recurrence of sprains in a population of athletes at risk.

All interventions will be performed by a qualified physiotherapist in a standardized manner. Tape will be extended to the recommended length (120%) and applied along the outer side of the leg, along the path of the peroneal muscle. Starting in the middle of the foot arch, the tape ends 1 cm below tibial head.

To assess postural stability, the following parameters will be measured: Autonomy: This measure represents the time the subject can stay on the mobile board without the use of his hand to maintain equilibrium. Mean axis spacing: This measure will be performed using an accelerometer localized on the sternum of the subjects. This device will allow us to calculate displacement of the chest (degrees of inclination). Mean error of the board: This parameter represents numerically the inclination of the board during the test. It allows to estimate the stability of the subjects' ankle (unit=degrees). The larger this value is the lower the stability will be. An estimation of total equilibrium between each subject will be assessed using the two parameters listed here above (mean axis spacing + mean error of the board) following recommendation of the manufacturer.

Inclusion Criteria: active elite basketball players Exclusion Criteria: no history of ankle sprain in the last 6 weeks no history of any other lower limbs lesion in the last 6 weeks