2026-09-24T20:55:51Z salford-repository.worktribe.com

oai:salford-repository.worktribe.com:1369027 2026-06-07T07:05:04Z 084104101115105115 openaccess

Thesis The effect of the Apos Therapy system on knee biomechanics in recreational athletes at risk of a non-contact anterior cruciate ligament injury An anterior cruciate ligament (ACL) injury is a catastrophicincident in sports, resulting in an extended period away from athletic participation and even potentially ending a playing career. The disparity between positive laboratory results of neuromuscular training programs and the actual effects on injury outcomes among high-risk populations suggests a missing link in current intervention programs. One proposed explanation for such a gap betweenlaboratory results and incidence outcomes may be related to the time-consuming, complex and difficult implementation of the techniques found to be successful in reducinglower limb movement mechanics and neuromuscularrisk factors. A novel option is to explore whether different unstable devices and unstable footwear designs may induce positive biomechanical and neuromusculareffects. The overall aim of this thesis was to determine the effect of an unstable device (AposTherapy system) on knee biomechanics and muscular recruitment patterns while performing functional tasks. To accomplish the research, four separate trials were conductedseparatly.Firstly, a repeatability trial with 11 healthy physically active (male and female)participants was conducted todetermine the reliability of the outcome measures for future studies. Secondly, as theAposTherapy system has not previously been trialled within the ‘at-risk’ female population, a feasibility study investigating whether using theAposTherapy interventionduring a six-week period was feasible was conducted. This was followed by a randomised clinical trial amongst 32 female recreational athletes who were indicated to have a high-risk(2D FPPA > 8.4º)indication for sustaining a non-contact ACL injury. Threegroups (control and two active intervention groups) were assessed at a six-week outcome point to determine changes in biomechanical outcomes. The results demonstrated positive biomechanical and clinical outcomes specifically in reducing the maximum knee valgus angle during a singleleg landing task while only using the AposTherapy system for walking. Furthermore, a significant reduction in maximum hip adduction momentsduring study tasks was observed when theAposTherapy system use was coupled with additional exercise. The thesis concluded with preliminary study investigating five individuals who were deemed at risk of a second non-contact ACL on their contralateral limb following primary ACL reconstruction(ACLR)surgery.There was a significant reduction in knee valgus angle during the single leg landingand single leg squat taskswhile only using theAposTherapy system for walking in the study with individuals who have had ACLR surgery.In summary, the results of this thesis showed that theAposTherapy system gave significant improvements in overall stability, with future studies needed to examine a larger-scale application especially in post-ACL reconstruction rehabilitation programs to mitigate the risk of a second ACL injury when athletesreturn to sport activities. However, more research should also focus on developing more affordable unstable footwear devices which could be incorporated in larger-scale prevention programs in the future. El-Zein, I Doctoral (Level 8) 2026-09-24 oai:salford-repository.worktribe.com:1369027 https://salford-repository.worktribe.com/file/1369027/1/PhD%20%2C%20IHAB%20SALAH%20ELZEIN_Final.pdf University of Salford https://salford-repository.worktribe.com/output/1369027 2026 en openAccess Public