How balance training can impact sensorimotor function in chronic ankle instability cases

One lateral ankle sprain can lead to ongoing condition
A single lateral ankle sprain is bad enough, but in certain cases, it doesn’t end there and can initiate a continuous condition known as chronic ankle instability (CAI). CAI is the tendency towards repeated ankle sprains and recurring symptoms (pain, weakness, giving way), and occurs in roughly 40-70% of patients who sustain a lateral ankle sprain. Individuals with CAI experience changes in sensorimotor system function that may lead to decreased postural control, joint position awareness and increased instability, which can cause further ankle injuries to occur. For this reason, rehab techniques involving exercises to enhance balance and proprioception (position sense) are extremely important, as they are likely to reduce recurring ankle sprains, but some claim evidence of effectiveness is insufficient. Therefore, a study was conducted that assessed the effects of a six-week balance-training program on subjects with and without CAI to see how it would impact balance, postural control and other factors.

Small study group evaluated with a number of tests
Twelve individuals with CAI and nine healthy volunteers participated in the study, and were screened using the Ankle Injury History Questionnaire and Functional Ankle Instability Index to determine CAI status. Participants were further assessed on dynamic balance, static balance, motoneuron pool excitability and joint position sense using a number of tests. Participants with CAI then completed a six-week balance-training program while the healthy subjects carried on with their normal daily routine without any ankle strengthening or balance training. The training program consisted of three sessions per week, with each session including four, three-minute balancing periods followed by one minute of rest.

Balance-training program shown to produce significant improvements
Comparisons based on the results indicated that subjects in the CAI group had significantly better dynamic balance than the control group according to post-test performance in reach distance in the anterior medial, medial and posterior medial directions. This suggests that balancing activities may improve sensorimotor deficits like dynamic balance and should be included in rehab protocols for those with CAI. There were no significant group differences in the static balance assessment, which may be explained by the small group size, but results did indicate greater motoneuron pool excitability and ability to recruit motor units in the CAI group, which may lead to improved soleus muscle response and help maintain better balance. Finally, those in the CAI group demonstrated better joint position sense, the ability to sense the location of a joint in space, after the program, further strengthening the likelihood that balance training may improve sensorimotor control. When taken together, these notable improvements clearly lead to improved balance and stability, and can reduce repeated injury and CAI. This supports the effectiveness of balance training, and it should therefore be implemented into rehab programs for those recovering from initial ankle sprains.

Summarized by Greg Gargiulo

As reported in the Feb. 11 edition of Journal of Orthopaedic & Sports Physical Therapy