Effects of specific closed kinematic chain excercises with biofeedback assissted position control and against forces enhancing positional disorder on lower limb movement pattern

Interventions is basically an exercises with resistance of the lower limbs in closed biokinematic chains, performed with modified "Leg-press" device. This kind of device allows only movement of extension and flexion of lower limbs against resistance - in this specific device (TELKO, manufactured/ distributed byACX/Technomex, Poland) resistance is created from elastic tubing. The only exercise performed will be flexion/ extension of lower limbs in closed kinematic chain made simultaneously for both limbs. The device uses virtual reality visual games to maintain patient focus in training and control parameters like force distribution between left/ right leg. The modification from standard training is due to active correction of the position of the feet and the axis of the lower limbs performed by the strength of the patient's own muscles, against the force disturbing this setting towards the valgus of the knees. The disturbing force will be realized through an elastic band (medium strength). The control of the position of the feet and the axis of the lower limbs will be performed with the use of biofeedback phenomenon and additional controls ( two on upper lowel leg, responsible for lower legs axis, and two on foot, responsible for keeping correct position / pressure of the foot). The exercises will last 15 minutes daily, with resistance and fatigue desribed by the patient as moderate to heavy but pleasant (3 to 5 in ten point Borg Scale). This exercise will be performed individually, as we have only one such device. As every participant will have individual account on the device software, report from every training session will be recorded and used for control of attendance and participation in training session. Speed of excercise - according to patient possibilities, but with instructions that primary goal is to perform the exercise correctly (according to attached controls described above) not speed or fatigue. Excercises will be performed for 5 days between the initial and final assessment - to avoid effects of muscle strengtening, instead of motor contol effect. Intervention will be delivered by Physiotherapist with active right to physiotherapy practice. The research will be held at "Pod Tezniami" Health Resort and Physiotherapy center in Ciechocinek, Poland. All patients will receive the patient's informed consent form to participate in the research, they will be informed in detail about the course of the research and that they can resign from participation at any time.