Fractures of the fibula can complicate ankle injuries
The lower end of the fibula forms part of the lateral ankle ligamentous complex
Since the lower third of the fibula forms part of the ankle joint, fractures sustained in this region will affect the mechanics of the ankle joint itself. This can result in complications where ankle injuries are concerned.
Fractures to the lower third of the fibula are often sustained in conjunction with higher-grade inversion injuries to the lateral ankle ligamentous complex, injuries to the syndesmosis or can occur independently.
In cases of trauma involving the ankle ligaments; the lateral ankle ligamentous complex for which the fibula provides the origins is most at risk. The lateral ligamentous complex is involved in most ankle injuries (Wang et al, 2014); hence the importance of emphasising this from a rehabilitation aspect.
Fibula fractures are quite common in football and frequently occur after a physical challenge where a direct blow is taken to the shaft of the bone; normally in the middle third if it’s an isolated break.
If the fracture occurs in the lower third then this can be a complication of ankle injuries, or if the break is in the upper third of the fibula this can arise in conjunction with knee injuries.
The fibula is usually referred to as a non-weight bearing bone whose primary purpose is to provide attachments for the muscles of the calf and the lateral ligaments of the ankle and knee. Because of the involvement of the fibula in the lateral ankle complex, some weight-bearing is inevitable.
Various authors have proposed that the exact extent of this varies between 6.7% (Takabe et al, 1984) and 17% (Wang et al, 1996) of body weight. Although others may differ in opinion, some authors argue that the fibula bears no physical weight at all.
Anatomically, the bones of the lower leg comprise the tibia, which is the thick weight-bearing shaft of the shin, and the long thin fibula which lies adjacent to the tibia on the lateral part of the limb.
The fibula extends down the lateral aspect of the lower limb from the knee to form the ankle joint. The shaft is long and thin and therefore vulnerable to the usual kicks and direct blows that are normal in football.
Fractures of the fibula are often referred to as the footballers’ fracture. This is because the fibula is normally the bone affected when a player takes a knock on the outside of the lower leg during the match.
We’ve often read in the past how somebody “valiantly played on with a broken leg; although clearly in a lot of pain” only for the player in question to come out with a statement to the effect that the club allowed him to continue in the game.
Since the bulk of the weight of the lower limb is taken through the tibia – or shin bone - this takes place when players try to "run-off" an undiagnosed fibular fracture in the mistaken belief that it's only been a kick.
However, unless it’s blatantly obvious at the time, it's very difficult to tell right away whether you are dealing with a simple bone bruising or a potential fracture.
Apart from the lower third which provides the upper part of the ankle joint, the fibula itself is hard to palpate on examination due to the surrounding muscles of the calf to which it provides a platform for their attachments.
The golden rule, of course, is to treat these injuries as potential fractures unless further advised.
Often the exact diagnosis of a fibula fracture comes a few days after the injury has taken place and once investigations have been completed.
This is the usual protocol to follow since a fair amount of swelling around the injury site can delay an in-depth initial examination and make an accurate diagnosis difficult.
As with higher-grade injuries involving the lateral ankle ligamentous complex, the exact recovery time following fibula fractures is always difficult to predict.
The average healing time for a fibula fracture tends to be around the six-week mark but you also need to allow for the bone mineral density to be at the right level before returning to play; otherwise, the risk of re-fracture is high.
With any fracture, once the initial inflammatory stage has passed, the natural reparative stage begins once the new cells start to form and then these begin to harden and mature into a stronger bone. It’s only once the latter has taken place that the fracture is anywhere near healed.
Some callus formation, which is the new bone formation surrounding the fracture site, should also be visible. Strength of the new bone is essential to the healing process and this is easily identified through medical imaging.
In terms of the risk of injury recurrence, it’s rare nowadays for a player to suffer an immediate re-fracture when coming back from injury. Modern return to play protocols, check MRI scanning and specific fitness testing tend to exclude the potential for recurrence long before the player is allowed to go back into the team.
However, it’s always worth bearing in mind that non-union of the long bones such as the fibula can become a problem depending on the nature of the fracture and whether any displacement has occurred (Soucacos et al, 2006).
Recovery from fibula fractures arising in conjunction with or accompanying ankle injuries isn’t always straightforward and often progress needs to be assessed continuously.
Since these are often sustained in conjunction with the original injury and can affect the early management process; the emphasis is placed on non-weight-bearing with crutches until a fracture or other bony injury of the ankle can be excluded.