I have been travelling through Athens and now Istanbul. My 11 year old is a Percy Jackson nut and has been filling me in with the who's who of Greek mythology and I am learning Latin words every day. Quite an education!
I looked up the word syndesmosis and the Latin translation is "(New Latin, from Greek sundesmos) bond, ligament, from sundein, meaning to bind together". As sports injury professionals, we know syndesmosis to be the joint articulation between the tibia and the fibula bones around the ankle. These two bones are ‘bound' together with very firm and strong ligaments.
Syndesmosis comes to mind after I saw a girl sprain a syndesmosis at the Archaeological Museum in Istanbul today. This poor girl was preoccupied by the hundreds of cats and kittens running all over the place and did not see the uneven cobblestones on which she placed her foot. At the same time, she turned to change direction. This is a common mechanism of injury for a syndesmosis - a forced dorsiflexion and rotation on a fixed foot.
It's the topic of my Rehab Masterclass in issue 140 of Sports Injury Bulletin.
Of all the ankle injuries, injury to the syndesmosis is the biggest pest to sports physios and the like. And unlike simple garden variety ankle sprains that heal quickly, the syndesmosis takes a LONG time to heal properly. If you deal with athletes that are susceptible to syndesmosis sprains, I'm sure you will agree that these are harder injuries to manage because of the severe consequences if done badly.
I go into a fair bit of detail in my Sports Injury Bulletin piece about syndesmosis injuries, detailing how they happen, how to identify them and then manage them. What I would like to highlight here are the implications of mismanaging a syndesmosis sprain.
In the current issue of The Journal of Sports and Physical Therapy, a group of Japanese researchers discovered that individuals who had chronic ankle instability (CAI) had a distal fibula that was positioned more lateral compared with healthy individuals with no CAI. In effect, those who had suffered serious syndesmosis injuries in the past and ended up with a wider distance between the fibula and the tibia, suffered more ongoing ankle pain than those without a tibfib separation.
Research shows that even a 1mm displacement of the talus within the mortise (due to a wider placed fibula) can reduce the contact area in the talocrural joint by 42% (Ramsey and Hamilton 1976). Mismanaged syndesmosis injuries, resulting in an excessive amount of opening, can lead to early onset arthritic changes and chronic ankle instability. The talus bone bounces around in the now wider tibfib articulation.
Typically, a widening of the fibula is due to one of the following reasons;
Poor initial management, whereby the athlete is allowed to weight bear too early and this weight bearing forces the fibula away from the tibia as the syndesmosis ligaments are trying to heal.
The degree of damage is so severe that proper tightening of these ligaments is not possible without surgical intervention such as a screw or similar being placed between the two bones to ‘force' them together.
The key for a sports injury practitioner, is to properly identify a regular ankle sprain from a more serious syndesmosis injury. If you get this part wrong and allow the athlete to get back to weight bearing too early, then expect some complaints about a chronically painful ankle some time down the track.
Kobayashi et al (2014). ‘Fibular malalignment in individuals with chronic ankle instability.' JOPST. 44(11); pp 841-910.
Ramsey and Hamilton (1976). J Bone and J Surgery Am. 58(3); 356-357.