Remember what I told you in a previous post about ankle sprain and its signs and symptoms, the most common ankle sprain is the lateral one, the one that affects the outside of your ankle. This is the reason why all the information I’am giving you is focus on the lateral ankle sprain (LAS).
Today’s post is about the risk factors and diagnosis of lateral ankle sprain.
Ankle sprain risk factors
- Limited dorsiflexion (click on the word to see explanation). If your dorsiflexion is limited, this could result in an increase of chance of twisting your ankle.
- High navicular- medial malleolus distance (NMM distance). If you have a look at the photo below, it is the distance between “D” and the lowest part of “B”. Have a look at this paper.
- Poor proprioception. This will mean that the receptors of your ankle/foot will not inform properly your brain about the position of your foot and, therefore, the risk of getting injured will be higher.
- Higher extension range of motion at the first metatarsophalangeal joint. This means that you can move your toe upwards quite a lot. Have a look at this study for further information.
- Reduced balance. It can be the result of poor proprioception or due to different conditions.
- Previous ankle sprains. Apparently people who have had previous ankle sprains are prone to have a new one.
- Sport practised. To be a football/soccer player, due to contact with opponents and to play volleyball or basketball, as they imply a lot of jumping are risk factors, as well.
All this can be found, explained in detail, in this paper.
Ankle sprain diagnosis
The ankle sprain diagnosis is usually made by your doctor or physio and what we normally do is to ask you several questions about the incident and then we have a look at your ankle (basically, to find out your signs and symptoms, explained in this previous post, that will give us the diagnosis). The most important part of the diagnosis is the importance of being sure that what you have is a sprain and not a fracture, so to know the way to rule out fracture is essential. If we compare the signs and symptoms of severe ankle sprain and fracture, they might sometimes be pretty similar, but a fracture has to be treated in a different way and that’s why it is important to know how to difference them. To diagnose a fracture it is necessary to have X-rays done, although we have what are called the Ottawa rules to know who might have a fracture and who might not. This way not everyone who sprains his/her ankle is exposed to X-rays (which is not healthy) and your health system (for example, the NHS if you live in the UK), or you, save some money. The rules are as follow:
1. Ankle X-ray is required if there is any pain in the malleolar (ankle bone) zone…
… + Bone tenderness at area A of the photo below ( distal 6 cm of the posterior edge of the fibula or tip of the lateral malleolus)
or …+ Bone tenderness at area B of the photo below (distal 6 cm of the posterior edge of the tibia or tip of the medial malleolus)
or …+ Immediately inability to bear weight or in the emergency department (for four steps)
2. Also, the Ottawa foot rules indicate that a foot X-ray is require if there is any pain in the midfoot area…
…+ bone tenderness at area C of the photo above (the base of the fifth metatarsal) (for foot injuries)
or…+ bone tenderness at area D of the photo above (the navicular bone) (for foot injuries)
or…+ immediately inability to bear weight or in the emergency department (for four steps)
Comments are welcome, either to make me shout the mouth or to help me to make this blog be better.
If you have any questions, do not hesitate to contact me on The Physical Therapy, Physiotherapy Clinic based in Southampton, and I will be happy to help you.