Reviewing ankle MSK exams
A young woman fell down in front of me today. Both she and I heard her ankle pop. I stopped to help. The following is 1) a review of what I did, 2) a review of a proper MSK exam, and 3) some things I probably should have done differently.
What I did
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I assessed her pain, and asked for basic history. Why did she fall, did she lose consciousness, did she hit her head or any other parts of her body? At the time I asked her these questions, she was not really in pain, and told me she was “feeling a huge adrenaline rush, so nothing hurts right now”. (I did not tell her about my own “huge adrenaline rush”, presumably originating from the fact that I have not done a physical exam in over half a year.) She did not lose consciousness, nor did she hit her head. She heard her right ankle pop.
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I helped her to a nearby shop so she could sit, and asked an employee for a bag of ice. I removed both her shoes and socks and assessed sensation to light touch (which was preserved). Both feet were warm. There were no overt signs of trauma to her foot, and at the time of this evaluation her ankles were the same size.
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I did a cursory MSK exam, with passive and active movement of her ankles (bilaterally) and knees (in following the principle of testing the joints immediately proximal and distal to the injured joint). Passive movement did not cause any pain. Palpation of the ankle joint did not show point tenderness, and Achilles tendon was also fine. Active movement was very limited (worse dorsiflexion than plantarflexion, and poor lateral movement as well). By this point, given the pop we both heard, her exam was more benign than I expected. I worried about a torn ligament or fracture, though fracture became less and less likely.
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I sat with her for the next roughly half hour icing her ankle and re-evaluating every several minutes, by which point it was pretty clear that her ankle was slowly swelling up. Here I offered to accompany her to an ED if she wanted, but she was insistent that she was on the way home and would rather continue on home. As I suspected bringing her to an ED would probably result in 1) a long wait, and 2) very little actually being done, I called an Uber to get her home instead. By the time the ride arrived, she was able to very gingerly bear weight on her ankle, and had no red flag symptoms. She went home with an ice pack and a recommendation to frequently re-evaluate for neurovascular compromise and to schedule an appointment with her doctor. I advised her to follow RICE (rest, ice, compression, elevation), and to take NSAIDs for pain.
Proper MSK exam
- Visual inspection - look for swelling, skin damage, hemarthrosis/ecchymosis, visible fracture/dislocation
- Palpate - lateral and medial malleolus
- Movement - passive and active movement (assess for Achilles tendon rupture with active ROM)
- Specific tests - anterior drawer tests (bend knee, hold ankle with right hand, use left hand to push heel forward), talar tilt test (similar to anterior drawer test, but laterally), external rotation test
- Neurovascular - pulse, warmth, sensation
Staging a sprain
Grade 1: microscopic ligamentous tear with no joint instability, mild swelling, and full weight-bearing capacity
Grade 2: partial ligamentous tear, moderate-to-severe swelling, ecchymosis, mild-to-moderate joint instability, difficulty bearing weight
Grade 3: complete ligamentous rupture with immediate-onset swelling, complete inability to bear weight
This woman probably has a Grade 2 ankle sprain, based on her ability to bear weight with difficulty.
Things I probably should have done
- I only did a cursory passive/active ROM exam, but should have better assessed for an unstable/dislocated joint with some of the aforementioned maneuvers
- I’m pretty confident this is not a case that requires emergency-room level attention, but probably should have emphasized that she should definitely try to see a doctor as soon as she can schedule one.
- I should have told her that complete immobility is not a good idea. As she looked like a pretty active person I’m guessing she’ll be itching to move anyway once her pain improves.