Syndesmose

Syndesmose, or syndesmosis, is a type of fibrous joint in which two bones are joined by ligaments or an interosseous membrane. This connection is more rigid than in most joints, and there is little to no joint cavity or cartilage involved. The syndesmosis class is one of the three main fibrous joints, alongside sutures and gompheses. The ligaments or membranes allow only limited or slight movement, primarily to accommodate loading and rotational forces.

In anatomy, notable examples include the distal tibiofibular syndesmosis, where the tibia and fibula are bound by the interosseous tibiofibular ligament and the anterior and posterior inferior tibiofibular ligaments. This syndesmosis stabilizes the ankle mortise and transmits load between leg and foot. Another example is the forearm syndesmosis between the radius and ulna, maintained by the interosseous membrane along their length, contributing to forearm stability and the mechanics of pronation and supination. There is also a proximal tibiofibular syndesmosis near the knee, and other less clinically prominent fibrous connections throughout the skeleton.

Clinical relevance centers on stability: syndesmotic injuries can occur with sports or trauma and often involve diastasis, particularly in the distal tibiofibular region. High ankle sprains affect the anterior and/or posterior inferior tibiofibular ligaments and may require imaging to assess the extent of injury. Treatment ranges from immobilization and rehabilitation to surgical stabilization when diastasis is present or instability persists, sometimes using screws or suture-button devices to restore tibiofibular alignment.