When you sprain an ankle over and over, it may be time to do something different. Some experts suggest taping the ankle. The idea is to increase the sensory messages to the joint and surrounding muscles. The hope is that this extra input will improve how quickly and accurately the ankle detects even the slightest change in position.
Proprioception is the term we use to describe the joint’s sense of its own position. Kinesthesia refers to detection of movement of a joint or body part. No one knows exactly why taping the ankle increases proprioception and kinesthetic awareness. It’s not really even clear if taping is what improves the joint’s ability to detect movement.
In this study, subjects with recurrent ankle sprains (three or more sprains in the last two years) were tested for change in proprioception with tape on the ankle. The researchers rigged up a footplate connected to a generator. The generator could move the ankle from side-to-side up to five degrees in each direction. Ankle motion with the foot turned in is called inversion. Ankle motion with the foot turned out is eversion.
Ankle inversion and eversion were tested with and without taping at three separate speeds of motion. Sixteen (16) people with recurrent ankle sprains were tested. It was expected that putting tape on the ankle to support and stabilize it would improve how quickly the joint detected changes in these two motions.
But, in fact, the authors report just the opposite. Instead of increasing the ankle’s ability to detect motion, having tape on decreased awareness of movement and joint position. Taping is known to reduce the risk of recurrent ankle sprains. The mechanism for this evidently isn’t because of an increased ability to detect changes in inversion and eversion.
Other studies have looked at the effect of taping on sprained ankles. They were never able to answer the question of whether taping improves movement detection or not. Several studies showed no difference in movement detection thresholds (how quickly the ankle perceives a change). Part of the reason for these conflicting results may be related to the quality of the studies done.
The authors of this report suggest that poor quality in experimental design may account for some of the different opinions on this topic. The protocol used in their own study was high quality, carefully following the principles of psychophysics. They don’t know why their results showed a reduced ability to detect ankle movements with taping in place. They offer several possible theories.
First, taping might reduce signals from the skin to the muscles and joint. The mechanism by which this happens is called cutaneous receptor discharge. Second, it’s possible that when the skin receptors signal the brain as to the location of the tape, it just adds noise to the nervous system, not actual helpful information. If the tape wasn’t applied in a way that stretched the skin during movement, then the proper signals weren’t sent to the nervous system.
It’s also possible that putting the tape on too loose or too tight altered the pattern of sensory signal patterns. The ankle wasn’t able to detect true sensory change. And several of the subjects did comment that they could tell the taped ankle was moving, but not in what direction. It was much easier to detect inversion-eversion ankle movement and the specific direction of the movement without the tape.
In future studies, applying the tape in a way that mimics the natural skin stretch patterns will be tried. Finding ways to tape that avoid stretching the skin in multiple directions is an important next step. In other words, they will try and match the normal skin stretch patterns that occur with inversion/eversion during testing with the tape in place.
Different types of tape should be tested. And an effort will be made to test where the communication break down occurs. Is it tape to skin, skin to muscle, or within the muscles themselves? For now, it’s clear that taping doesn’t reduce the risk of future sprains because of its beneficial effects on proprioception during inversion and eversion ankle movements.