Ligament instability in the ankle joint

The ankle joint complex includes various ligaments. They stabilise the joints in conjunction with muscles that encompass the joints. A corresponding stability of the ligaments is a prerequisite for proper joint mobility and stabilisation.

Congenital or acquired factors can cause ligament weakness (laxity). This commonly results in instability of the joints. Hyperextension of the ligaments or a torn ligament can even cause a complete loss of stability in a joint.

The causes of instability, which primarily occurs in the upper ankle joint, can include a congenital or acquired ligament weakness with or without the involvement of other, stabilising structures (for example, the joint capsule, articular cartilage, menisci and muscular structures). Whether external force is involved or not, twisting the ankle can cause the ligaments in the ankle joint to stretch excessively or even to rupture. In general, instabilities in the ankle joint are defined by the number of affected ligament structures. The more ligaments are affected, the more unstable the ankle joint complex will be.

Initially, instability manifests itself in uncertainty while walking, which may be associated with pain and grinding noises when more weight is placed on the joint. Swelling and discolouration occurs in the affected area with acute instabilities, for example, due to a torn ligament. Over the long term, and especially if acute injuries are not properly treated, this is often followed by chronic instability or arthrosis, which is more rapid degeneration of the articular cartilage in the joint.

When an instability in the ankle joint complex is confirmed by manual test procedures, such as the talar tilt test, diagnostic imaging procedures such as MRI, X-rays or ultrasound often follow.

There are acute and chronic instabilities of the ankle, which are each treated differently in terms of their clinical care and careability. The therapy depends on the cause and the severity of the instability. It is usually done conservatively, i.e. without surgery. In conservative therapy, physiotherapy and stabilising orthoses are at the forefront of treatment. In the event of instability due to a torn ligament, a phase-appropriate treatment with an orthosis along the healing phases is essential. Inadequate care often leads to chronic instability in the ankle complex.