ONE-FOOT VERTICAL JUMP WITH APPROACH IN UNILATERAL TRANSTIBIAL AMPUTEES

The aim of the study was to assess the biomechanical technique used by transtibial amputees to reach maximum flight height in a 1-footed vertical jump with an approach from the sound and prosthetic sides. Through this assessment, alterations to jump biomechanics could be identified and compensatory mechanisms detailed. METHODS Three male transtibial amputees were asked to perform maximal one-legged vertical jump with approach from their right and left limbs. Of the three, only two were comfortable completing the task and achieving height from the prosthetic side. One participant withdrew from the research. Both remaining participants were traumatic left-sided amputees and were healthy and active and free of musculoskeletal injuries. Participant one (P-1) had a mass of 69kg and height of 1.78m. The amputation had taken place 8 years prior to testing. Participant two (P-2) had a mass of 81kg and height of 1.77m. The amputation had taken place 12 years to testing. For the motion capture, a seven camera VICON 512 retro-reflective motion analysis system was used. The cameras were operating at a frequency of 120Hz. Thirty-three retro-reflective markers were placed with tape on the head, trunk, arms and legs. Onefoot vertical jumps with an approach were analysed. The participants took a 2-3 step approach followed by a take off from the sound limb or the prosthetic limb. The instruction to the participants was simply to jump as high as possible. Both participants warmed up for about ten minutes prior to data collection and they were allowed sufficient time to practice the jumps. At least 3 practice attempts were taken. Each participant then performed three jumps of each type and the best jump, defined by maximum height of the Centre of Mass (CoM) was selected for further analysis. RESULTS AND DISCUSSION Outcome results for the subjects are presented in Table 1.