Diagnostics
An important point of reference for the doctor is the medical history, i.e. the description of the situation in which the injury occurred. In addition, the physician will look at the mobility of the foot (motor function) and whether there is a loss of sensitivity (the sensation in and on the foot). X-rays in several planes (lateral and front-back) can provide more precise information about the talus fracture. Furthermore, a further diagnosis in the computed tomography (CT) scanner may be appropriate to provide a more precise image of a possible fracture. MRI and bone scintigraphy can be a decisive means of excluding or detecting possible damage in the affected bone parts.
Frequency distribution
The talus fracture is rather one of the rarer fractures. It accounts for less than 5% of all foot fractures. A talus fracture often occurs in combination with other fractures in the foot area, e.g. the malleoli (ankle) or calcaneus (calcaneus).
In half of all cases, a talus fracture affects the neck of the ankle bone. Fractures of the ankle bone make up about a quarter of all cases, while fractures of the bony projections of the talus (processus) affect about a fifth of all cases. Symptoms: A talus fracture causes severe pain in the area of the ankle joints. There is also a severe swelling with hematoma (bruise). In addition, the mobility in the ankle joints is restricted.
Classification
The classification of a talus fracture of the ankle bone neck is based on Hawkins’ guidelines. In type 1 there is no displacement of the collum tali. Type 2 is present when the fractured neck of the ankle bone is displaced forward in the lower ankle joint.
Type 3 describes a condition in which the body of the ankle bone is displaced in the upper and lower ankle joint. In type 4, the status is the same as in type 3 and there is also a displacement in the Articulatio talonavicluare. The talonavicular joint is the joint between the caput tali and the os naviculare (scaphoid).
A talus fracture with displacement must be reduced as quickly as possible (brought back into the correct position) in order to minimize the risk of osteonecrosis (death of the bone). A distinction is made between displaced and non-displaced fractures in the lateral and posterior talus processes. If there is a dislocation of the bone fragments, they are moved back into the correct position with screws.If the fracture does not show any displacement, treatment with a plaster cast that immobilizes (immobilizes) the ankle is sufficient.
Talus fractures of the talus head are usually fixed with screws. Spongosiaplasty may be indicated here. This is a procedure in which healthy bone tissue (spongosia) of the patient is introduced into the fracture with the aim of creating stable bone substance by means of adhesion with the bone tissue there.
The healthy bone tissue is usually taken from bones that are easily accessible (e.g. parts of the iliac crest). Plaster can also be used for fractures of the Collum Tali if there is no dislocation of the fracture pieces. If a dislocation has occurred, as with Hawkins 3 and 4, and often also with Hawkins 2, a reconstruction with screws is performed.
If a fracture produces small bone fragments, which often happens at the small bone protrusions that are not held by screws and therefore cannot be reduced, then there is the possibility of arthroscopic removal of these fragments. Complete weight bearing of the affected foot should be prevented until the 8th – 12th week. Partial weight-bearing may also be possible before this time if screws were used. After the operation, a radiological follow-up of the fracture is indicated in order to monitor the healing process and detect complications. Lymphatic drainage and physiotherapy may be helpful to accelerate the healing process.
