Recovery From Mild-To-Moderate Ankle Sprains
Many physically active people sprain their ankles. But not very many are sent to physical therapy. Some of those injuries occur over and over. The result can be persistent pain, weakness, and joint instability.
In this study, researchers asked the following questions. Do grade I (mild) and grade II (moderate) ankle sprains recover naturally (on their own)? Is more than standard advice of protection, rest, ice, compression, and elevation (PRICE) needed?
Fifty (50) people with acute ankle sprain (occurred in the last 72 hours) were studied for one month. All were first seen at an emergency department and discharged home with a PRICE program. While at the hospital, a senior physical therapy student assessed each one for this study.
Range-of-motion (ROM), strength, swelling, and bruising were measured and recorded. ROM and strength of the uninjured ankle/foot was measured first. A special handheld tool called a goniometer was used to measure motion of the ankle. The therapist performed a manual test of strength by resisting the patients’ motions by hand. Those measurements were used as a normal value for comparison to the injured ankle.
Everyone was given a way to protect the joint using an elastic ace wrap. Instructions were given to rest, use ice off and on for 48 hours, and elevate the leg to reduce swelling. Gentle ROM exercises were prescribed along with over-the-counter medications to alleviate pain and reduce swelling.
Four days later, patients were retested by the physical therapy student. A more sophisticated method of measuring motion and strength with a Biodex isokinetic dynamometer was used. Once again, both sides were measured and recorded.
In addition, the therapist looked at ankle function in daily activities, sports, and recreation. The Foot and Ankle Outcome Score (FAOS) was the self-reported survey used to assess function. These same tests were completed a final time 30 days after the first visit to the emergency department.
Some patients did not come back for the follow-up tests. In the end, the results of 28 patients were analyzed. Everyone was able to gradually resume most (but not all) of their previous activities. Mild pain and swelling with mild loss of motion left some patients unable or unwilling to participate in sports and recreational activities.
Everyone did get better as time went by. But at the end of one month, weakness of the plantar flexor muscles (used to rise up on toes or point the toes) and loss of ankle motion were still present.
This study showed that on the outside, people with mild-to-moderate ankle sprains seem to recover. But a closer look showed some significant deficits in motion and strength. It's these undetectable differences that could lead to future reinjury and recurrent ankle sprains.
And it's possible that even a small amount of long-term swelling can result in a loss of normal neuromuscular function. After an acute ankle sprain, the ankle joint doesn't have normal proprioception (sense of joint position). Even a small loss of proprioception can affect athletic performance.
Likewise, pain can keep a person from moving through the normal, full arc of motion needed for daily and sports activities. Fear of pain and an unwillingness to move the joint can reduce function. This is true even when there is enough motion and strength present for full function.
The authors make two summary observations from the results of this study. First, measuring ankle motion with a standard handheld goniometer used by physical therapists may not be sensitive enough to detect the full measure of ankle impairment. Likewise, the use of manual muscle testing for ankle injuries is not as accurate as using a dynamometer system.
Second, standard care after a Grade I or II acute ankle sprain may not be enough to ensure full recovery and return to full function. The authors suggest management of acute ankle sprains with physical therapy may be a good idea. This could improve results within the first 30 days.
More studies are needed to prove this and to see if patients recover fully with standard care when given more than 30 days. Results of natural recovery may be different after six to eight weeks.
Alice B. Aiken, PT, PhD, et al. Short-Term natural Recovery of ankle Sprains Following Discharge From Emergency Departments. In Journal of Orthopaedic & Sports Physical Therapy. September 2008. Vol. 38. No. 9. Pp. 566-571.