Effect of strength and proprioception training on eversion to inversion strength ratios in subjects with unilateral functional ankle instability

Abstract

Objectives: To examine the effect of six weeks of strength and proprioception training on eversion to inversion isokinetic strength ratios (E/I ratios) in subjects with unilateral functional ankle instability. Methods: Thirty eight subjects were randomly assigned to one of four treatment groups: strength training (S); proprioception training (P); strength + proprioception training (B); control (C). Isokinetic strength was tested before and after training using a Kin Com 125 automatic positioning isokinetic dynamometer. Subtalar joint eversion and inversion motions were tested both concentrically and eccentrically through a range of motion involving 40°. All peak torque and average torque values were normalised for body mass. E/I ratios were calculated from average torque and peak torque measures by taking the concentric eversion value and combining it with the eccentric inversion value. Data were analysed using a mixed model analysis of variance with repeated measures on the test factor. Average torque and peak torque E/I ratios at 30 and 120°/s were analysed separately. Results: There were no significant differences in average torque and peak torque E/I ratios of the functionally unstable ankle for any of the groups after training compared with before. Conclusions: Six weeks of strength and proprioception training (either alone or combined) had no effect on isokinetic measures of strength in subjects with self reported unilateral functional instability. Further studies examining this agonist (concentric) to antagonist (eccentric) muscle group strength ratio are needed.

Current concepts on the pathophysiology and management of recurrent ankle sprains and chronic ankle instability

“…This study used Thera-Band Ò elastic bands to perform inversion, eversion, dorsiflexion and plantar flexion as well as perturbation during a single limb balance exercise over a four week, 12 session rehabilitation program. There were no differences in eversion/ inversion isokinetic strength between subjects with ankle instability and healthy control subjects [86]. In contrast to this study, Docherty et al [87,88] found increased dorsiflexion and eversion strength following six weeks of strength training.…”

“…To address muscle weakness and function, Kaminski et al [86] intervened with strength training and proprioceptive training on subjects with ankle instability and a history of recurrent sprains. This study used Thera-Band Ò elastic bands to perform inversion, eversion, dorsiflexion and plantar flexion as well as perturbation during a single limb balance exercise over a four week, 12 session rehabilitation program.…”

Comparison of a strengthening programme to a proprioceptive training in improving dynamic balance in athletes with chronic ankle instability (CAI)

“…If the ankle musculature is strong, the athlete can withstand greater force before an injury is sustained. In addition to decreasing ankle injuries, strengthening lower leg muscles will help prevent injuries [3].…”

Lower Extremity Muscle Activation in Patients With or Without Chronic Ankle Instability During Walking

“…Alterations in lower extremity kinematics during gait [16][17][18][19] and jump landings 20,21 also are evident in individuals with CAI, whereas strength deficits are controversial. [22][23][24][25][26] It is unclear whether these deficits and alterations occur in individuals before or after an initial ankle sprain.…”