By Bridget End, PT, DPT. It’s that time of year when more people are trail running and hiking, putting themselves at increased risk of spraining an ankle. There are different levels of severity of ankle sprains, some that have minimal impact on daily function and some that sideline you for weeks, or even months, from the activities that you enjoy. The level of severity depends on the amount of damage that is done to the ligament(s): Regardless of the severity, all ankle sprains require at least some rehabilitation in order for the ankle to regain its normal function and to prevent recurrent sprains. One of the key aspects to focus on when rehabilitating an ankle sprain is proprioception. What is proprioception? Proprioception is “the perception or awareness of the position and movement of the body.” (Oxford Dictionary). Our brain senses body positions and movements via signals that are sent to the brain from proprioceptors, which are neurons located in joints, muscles, tendons, and ligaments. For instance, if you step on a rock and start to roll your ankle, proprioceptors in and around the ankle joint signal to the brain the new position of the ankle, resulting in the brain telling various ankle muscles to contract to prevent the ankle from rolling any further and return it to its neutral position. Proprioception is critical in maintaining balance and stability, as it is one of the three systems that work in conjunction to maintain our balance (the other two systems are vision and the vestibular system). When one of these systems is impaired but the other two are intact, we can still maintain adequate balance. So, a deficit in proprioception may not be obvious until you start to challenge one, or both, of the other two systems (e.g. challenging vision by walking in the dark, challenging the vestibular system by bending over to pick an object up off of the floor). Why does this matter? Many everyday movements, such as walking, hiking, running, and going up and down stairs, require us to have adequate ankle proprioception to maintain our balance while only one foot is on the ground at a given time. We rely even more heavily on our proprioceptors when ambulating on firm, but uneven ground (e.g. a rocky trail) and when ambulating in the dark (and especially when ambulating on uneven ground in the dark!), since our other balance systems are being challenged in those instances. Following a trauma (e.g. acute injury, surgery), local proprioceptors become inhibited. So, after an ankle sprain, proprioceptors in and around the ankle joint become impaired, sending inaccurate, fewer, and/or delayed signals to the brain. As a result, the brain is less equipped to maintain good positioning of the ankle joint, resuling in an increased risk of re-rolling the ankle. Recurrent ankle sprains result in more impaired proprioception, which further increases our risk of subsequent ankle sprains. This leads to a vicious cycle of chronic ankle instability, which can result in permanent ligament damage, cartilage and bone degradation and eventually ankle osteoarthritis. What to do about it? Even after a traumatic ankle sprain, it is posible to improve the function of our proprioceptors to regain ankle stability. You can do so by performing balance exercises that challenge either your vision or your vestibular system, thereby forcing you to rely more heavily on your ankle proprioceptors. Daily consistency with these exercises can result in rapid improvements, allowing you to get back to hiking or trail running ASAP. You can schedule an appointment with a physical therapist to get a set of exercises that are the appropriate level of difficulty to improve your ankle stability and get you back on the trails with the confidence.