The objective of this study was to investigate the effect of an anterior to posterior mobilization of the talus on two groups of individuals. Talus mobilization is a common technique used by manual practitioners in an attempt to increase the range of motion of the talocrural joint. This technique is often applied after individuals have sustained a lateral ankle sprain/strain;​ as these individuals often experience a decrease in dorsiflexion after injury. Due to the high recurrence rate of lateral ankle sprains, investigating kinetic and kinematic variables within these individuals after an anterior to posterior mobilization to the talus is important to advance our understanding of this common injury and modality. The two groups of individuals investigated in this study include those without a history of ankle sprains, referred to as the "Control" group, and individuals with Chronic Ankle Instability (CAI). A total of 20 participants were involved in the completion of this study;​ 10 were Control participants and 10 were individuals with CAI. The Control group consisted of 4 males and 6 females with an age range of 18 - 31 (Mean = 24.7 + 3.8 years of age), body mass ranged from 50 - 94 kg (Mean = 69.9 + 15.23 kg), and their height ranged from 1.59 - 1.88 m (Mean = 1.72 ± 0.1). The CAI group consisted of 8 males and 2 females with an age range of 18 - 30 (Mean = 24.7 ± 4.4 years of age), body mass ranged from 5 4 -1 1 0 kg (Mean = 81.4 + 15.9 kg), and their height ranged from 1.68 - 1.92 m (Mean = 1.81 ± 0.07). The study occurred in the Biomechanics Laboratory at W ilfrid Laurier University. Individuals were tested during three functional tasks;​ a novel approach as these individuals have largely to date been tested during static conditions. Functional tasks included a squat, single limb stance, and a two foot jump landing on the affected/unaffected limb. Objective measures used to compare Control and CAI participants in this study included;​ knee to wall test, range of ankle motion, maximal angle of dorsiflexion, center of pressure, center of pressure and center of mass difference, peak vertical ground reaction force, time to peak vertical ground reaction force, loading rates from landing, and instantaneous axis of rotation of the talocrural joint. Outcomes were compared within groups at pre-mobilization and post-mobilization. Outcomes were also compared between groups.

Differences existed between the CAI group and the Control group in this study across a majority of the objective outcomes. Differences were also evident at pre mobilization values and post mobilization values between both groups. An anterior to posterior mobilization increased the knee to wall test regardless of previous injury history. An anterior to posterior mobilization appears to decrease stability and control during the squat, and single leg stance for both groups along the anterior posterior axis. An anterior to posterior mobilization may improve stability and control during closed chain and static tasks in individuals with CAI along the medial lateral axis. An anterior to posterior mobilization does not appear to influence the ability to absorb shock during impact. This also confirms that the force of mobilization can remain consistent when performed on different days by the same practitioner.