Ankle joint fracture

Ankle joint fracture: What’s that?

The ankle joint is one of the most burdened joints in the body. Anatomically, it is split between the upper and lower ankle joint. The upper ankle joint is responsible for bending and stretching the foot, whereas the lower ankle joint is mostly responsible for the supination and pronation of the foot.

The outer and inner ankle form the so-called malleoli prong. It surrounds the talus like a clasp and ensures sufficient stability in the upper ankle joint. A strap-like connection, so-called syndesmosis, ensures additional stability in the lower leg. The lower part in the region of the malleoli prong is described as “syndesmosis tibiofibularis”.

If osseous structures are broken in the region of the upper ankle joint, we speak of ankle joint fractures which are split according to the Weber classification in 3 types A, B and C.

Weber A fracture: Fracture of the upper ankle joint (UAJ) below the syndesmosis. For this fracture type, the syndesmosis is always uninjured.
Weber B fracture: Fracture of the upper ankle joint (UAJ) at the height of the syndesmosis. The syndesmosis can be intact or injured.
Weber C fracture: Fracture of the upper ankle joint (UAJ) above the syndesmosis. The syndesmosis is also always injured.

In addition to a Weber fracture, the ankle joint surface on the inner ankle can also break off wedge-shaped. This fracture type is described as the “Volkmann triangle”

Cause of an ankle joint fracture

The most frequent cause of an ankle joint fracture is a so-called supination trauma (twisting outwards by force). An external trauma is more seldom as a cause.

Twisting outwards means a sudden, very strong force on structures in the ankle joint. This results in sudden overloading of the bones and ligaments.

Consequentially, the ligaments may be injured or bones broken. If a broken bone has been caused by a supination trauma, the outer fibula is more often affected. It is also possible that the inner tibia is affected.

Diagnosis of an ankle joint fracture

In addition to the case history (e.g. questioning regarding the course of the accident), inspection and physical examination of the affected region play an extremely critical role.

Using imaging procedures such as X-rays, the physician can recognise a fracture and localise it precisely. Equally, the physician can also determine according to the images whether instability already exists between the tibia and fibula. This would indicate participation of the syndesmosis. In this case, a wider gap can be recognised between the tibia and fibula.

Therapy for an ankle joint fracture.

The therapy depends on the extent of the injury and can either be conservative (treatment without an operation) or operative. This decision is taken by the treating physician.

In case of conservative therapy, the foot is immobilised for approx. 6 weeks (depending on the therapy plan) with a lower leg foot brace such as the BORT X-Walker long, at 90°. This should hinder that the injured malleoli prong is burdened by the natural course of movement during the healing phase.

However, treatment without an operation is normally only possible for Weber A fractures. If the syndesmosis tibiofibularis is also affected or the fracture is complex, mostly operative therapy must take place. Also, Weber B and C fractures are generally operated.

The operative therapy reduces and fixes the bone fragments anatomically. This can be done using screws and plates, for example. Following this, the foot is also immobilised for several weeks with a lower leg foot brace such as the BORT X-Walker long.

In order to secure therapeutic success, additional rehabilitation measures such as physiotherapy can be prescribed, both as a follow-up for conservative and for operative therapy.

How can ankle joint fractures be prevented?

As most ankle joint fractures arise from unpredicted traumas, it is very difficult to avoid them.

Regular exercise and targeted training such as the BORT ankle joint exercises (german version) support the stabilisation of the ankle joint. Also, a healthy and balanced diet can contribute to better mineralisation of the bone.