The scourge of ankle sprain–when it happens once, it’ll probably happen again, an occurrence called recurrent ankle sprain. The first sprain often harms the sensors within the joint, muscles, and ligaments of the ankle. Many times, this causes the ankle to become unsteady, a condition called functional ankle instability.
An effective treatment for ankle sprains is “disk training.” A circular platform with a small sphere under it, the disk looks a bit like a spaceship. Patients place their feet on it and work the ankles by tilting the disk in various positions.
Doctors and therapists are convinced the disk works. Rightly so. These treatments are proven to improve balance, decrease ankle pain, and help keep people from having another ankle sprain. Okay, so the treatment works–but how? What does it do to help people get better and protect them from reinjury?
A unique study looked at whether disk training quickened the response of muscles around the ankle at the moment the ankle begins to sprain. Researchers had eight patients with past ankle sprains stand on a platform with a trapdoor. Without warning, the trapdoor would release, causing patients’ ankles to turn in–the most common position of the ankle when it sprains. Electrical tests measured how quickly the muscles around the ankle joints responded. Both ankles were tested, giving a comparison between injured and healthy ankles.
After the test, the patients were sent home with a disk and instructions to work the injured ankle 15 minutes per day. Participants came back eight weeks later, and the trapdoor tests were repeated.
The training made a difference in how quickly ankle muscles responded. The main shin muscle, the anterior tibialis muscle, showed the greatest improvement. What’s even more peculiar is this muscle got faster on the other leg too, the one that wasn’t worked on the disk. The effect of training somehow crossed over to the other side. This raises the question whether patients with severe ankle sprains might benefit by starting disk treatments right away on their uninjured ankles.
These research findings shed light on how disk training works. The results add valuable information for those who are involved in designing the best methods for rehabilitating ankle sprains.