The ankle sprain might be the ultimate equal opportunity injury. No other injury has crossed so many demographics, sports, and activities, shutting down activity equally for postal workers, grade school children, first responders, and NBA starters alike. If you're like me, you've likely sprained your ankle several times without complication, but remember that single instance requiring a trip to the doc and a really fancy boot or brace.
My name is Dr. Allan Buccola, physical therapist and owner of Impetus Physical Therapy in Greensboro, NC. The inversion ankle sprain may be taken the least seriously of joint sprains in some regards. Many of us live a life of recurrent sprains, and few doctors understand the value and necessity of properly rehabilitating this joint. Let's take a quick look at inversion sprains and why it's critical to take some time to bring it back on-line.
What is an inversion sprain?
An inversion ankle sprain, or a lateral ankle sprain, is a when a loss of footing stability results in the sole of the foot turning inward, and load bearing forces occurring while the outer portion of the foot is in contact with the ground. The typical anatomical structure of the ankle results in a near 90% prevalence of sprains occurring in this direction.
In America, 2 out of every 1000 people will sustain a sprain this year. Demographically, inversion sprains tend to peak in males between 14-24 years, and in females over the age of 30. About half of these occur during sports, with basketball topping the list, but also high in prevalence are instances taking place in the military, as well as other tactical athletes such as police, fire fighters, and EMTs.
The sudden and severe loading through the joint while inverted creates harmful stresses through multiple types of tissues. Medically, we used to discuss sprains in terms of damage to the ligaments only, or if the sprain was bad enough to break some bone. In reality, rehab specialists know far better now, and acknowledge that only focusing on ligament healing after a sprain will not fully determine recovery or readiness to return to sport/life.
Know the different grades
Traditional grading in sprains places them into one of three categories. Grade-I sprains are thought to only create a mild to moderate stretch to the outside ligaments in the ankle, with no 'tearing' of tissue that would be seen with the naked eye. Grade-I sprains can run a very broad continuum of severity, from an event that is easily shaken off with no ramifications whatsoever, to increased swelling, pain, bruising, and pain with bearing weight.
A grade-II sprain can present similarly as a bad grade-I, but the difference may ultimately not been seen until swelling goes away 3-4 weeks later. In a grade-II sprain, greater trauma is present to the ligament/s to the degree of some mild tears. Although variable between people, these sprains will require additional time to heal. If trauma is severe enough to the ligament/s, permanent joint integrity may be lost in the ankle.
In a textbook grade-III strain, forces are sustained great enough for either A. damage to almost the entire lateral support system of the ankle (3 ligaments and joint capsule) to occur and/or B. high stresses on the ligament will damage or even break off the bony attachment. This grade of sprain will almost always require surgical intervention, and of course a far greater amount of time for healing.
Being that these definitions are categories around the construct of anatomical structure damage, assessed only with use of medical imaging, there have been other attempts to qualify this grading system. Some have described the grades by the amount of swelling, or the amount of dysfunction after the event. Loud popping sounds are also common during a sprain event but do not provide any useful information in terms of grading.
These are great for dinner party conversation, but have little relevance in the rehab world. In reality, each person has a different response in terms of swelling, pain, and bruising. Additionally, ankle inversion trauma can result in many other injuries aside from sprains, which require different types of interventions aside from surgery and/or immobilization in a boot. This PT would not recommend you attempting to grade a sprain without help from a medical professional...but please, dinner party on!
Tissue damage and long term implications
As mentioned above, sprains are typically described in terms of ligament damage or a loss of joint integrity. These are joint structures used to describe a joint injury. Unfortunately, the joint is attached to a bunch of other important stuff. Let's not forget these.
Joint proprioceptors are the tiny little sensors wired to your nervous system. They exist in the muscles, tendons, ligaments, and more, and give you information about foot and ankle position without having to look at them. Often taken for granted, it's actually really cool to consider that your brain knows what angle each joint in your leg is currently in, and is fine tuning adjustments to all of them simultaneously to keep you standing.
After a single sprain event, and especially with recurrent, these tissues are also damaged and need to be 'reprogrammed' to function optimally. A failure to do so, results in impaired balance setting you up for future injury. After all, the recurrence rates for sprains are high: one study shows around 15% re-injury within two years for track and field athletes and another showing close to 70% for basketball players.
Although not as traumatic structurally, stresses on the peroneus brevis and peroneus longus can create some variable dysfunction. These muscles (and their tendons) are the primary evertors of the ankle, maintaining weight bearing through the medial arch, and creating pronation (push-off through the 1st toe) during walking and/or running. A sprain event can result in some weakness, pain, or tendinopathy, at best, but will no doubt compromise a key strength component vital for balance and ankle stability.
Without going into too much more detail, there can also be damage to the joint capsule itself, mild bony fractures, nervous tissue compromise, or even some displacement of the cuboid. The bottom line here is this: not all sprains are created equal, and each person will present with a unique set of difficulties after their injury has healed.
Do preventative measures work?
A study from 2011 that looked at more than 1000 high school basketball players found using a lace-up ankle brace had a strong effect in reducing sprains. For athletes who had no history of sprain, those wearing the brace sustained only 30% as many sprains as those unbraced. For athletes with a history of prior sprain, those in the brace sustained only 39% as many ankle injuries as those without. Interestingly, for all injuries that occurred during the study, there was no significant difference in severity regarding brace utilization.
To address the next logical question, a 1993 randomized study with more than 600 collegiate basketball players tried to assess the effect of high-top v low-top sneakers on sprains. Interestingly, there was no significant difference between the two shoe styles in terms of sprains during game play.
A smaller study following cross country runners at Harvard tried to observe any effect foot strike might have on injury. Although they found the heel striking runners to sustain twice as many overuse injuries as the forefoot strikers, foot strike played no significant difference in acute traumatic injuries (sprains included.)
In a 2016 study, trying to identify risk factors related to ankle sprains in soccer players, researchers looked at strength in the hips specifically. They found that the greater the strength in the hip extensors, the lower the incidence of ankle sprains.
Neuromuscular conditioning programs have been shown to be highly effective in preventing sprains in high school and collegiate athletes, as well as reducing injury recurrence. These have been successful when performed as a part of team conditioning or simply as part of a supervised rehabilitation program.
How does physical therapy address a sprain?
Physical therapy offers in-depth patient education on safe self-management of pain through a variety of means. This is integral to getting patients off of pain medications sooner, and back to daily functional tasks faster.
Joint integrity and quality
At the point where the healing process is well underway and swelling is well managed, the integrity of the ankle joint is assessed to assure normal and appropriate tension remains in the joint. Any remnant laxity will create changes to joint stability during all physical activity, and like any other joint in the body, will require greater contribution from the muscular system for stability.
As recovery and healing continue to progress, it will be critical to assure that there is a return of normal joint range. A loss of dorsiflexion (bending the foot up while in stance) has been shown to contribute to increased risk of subsequent ankle injury. PT can help to teach correct stretching and provide hands-on joint mobilization to guide the ankle back to recovery. This is especially important after a period of immobilization.
Not simply related to any direct insult to muscle or tendon, a period of immobilization in a brace or boot can create a quick loss of muscle mass, typically most noticeable in the calf. PT will help regain lost strength, so that a short lived injury doesn't result in lasting dysfunction of walking and running mechanics.
Restoring strength is not simply a matter of gross force: its also about restoring the delicate balance of strength between all of the muscle groups. One study showed that high school athletes having sustained an inversion ankle sprain, demonstrated alterations in strength production in their gluteus maximus and hamstrings on the same side.
balance & motor control
Once joint range, strength, and swelling are back on track, restoring balance and motor control in the system will be critical. This is often the biggest remaining deficit for those who never seek treatment after a sprain. Balance training is critical to teach the ankle to coordinate better with the hips and trunk for remaining upright. Motor control takes this concept and applies movement in a variety of positions, velocities, and perturbation to maximize performance of the system as a whole.
Functional Test Measures
How do we know when it's safe to return to work or sport? This is the age old dilemma as we all appreciate the risks of going back too soon. Impetus PT utilizes clinically validated functional movement assessments such as the Y-Balance Test, FMS, and various hop tests, to bring an objective scoring system to total body function and maximal effort activity. We work hard together to make the ankle better than it was before, and then we can put it to the test.
advocate for yourself
Not every ankle sprain warrants physical therapy: I hope that's not the message you got from reading this. I suffered a nasty sprain in 2009 while running the Laurel Bluff trail, after stepping in a leaf covered hole...and that's how it goes. Similar to acute knee injuries in sport, many will be the result of extreme changes in terrain or blows to the side of the leg. There is no amount of stability training or ankle bracing that will prevent all sprains.
Consider, however, that the other 50% of these injuries can be largely avoided or substantially minimized. As an avid trail runner, I tackle uneven terrain in the most fatiguing of scenarios. My last race involved around 15 stream crossings and 31 miles of trail. At some point, a loss of stability will occur, and the more quickly and strongly you are able to recover from that loss of balance, the less severe that injury will be.
If you continue to struggle with performance or even daily mobility from a sprain, speak up for yourself. We live in a world now where you must advocate for yourself for the best medical care. Your general practitioner cannot be a specialist in all things, but YOU will truly be the best judge as to whether you have fully recovered your function after a sprain. Remember it's not just about tissue healing, it's also about retraining the system to function as a singular unit again.
Until next time, don't stop moving!
If you feel you can do so in a safe manor, screen yourself for symmetry at home:
- Use a watch to time your single leg stance balance and compare both sides. Normal population values for this should easily exceed 30 seconds. If you are an athlete, how long do you think this should be for your sport?
-Repeat this test with eyes closed to better evaluate the proprioceptive abilities of the joint. Normal population values for this vary, but 4-7 seconds is a good target depending on age. If you are an athlete, how long do you think this should be for your sport?