Ankle Fractures

Ankle fractures are a frequently seen injury in both the general population and also occur frequently in contact sports. In clinical practice I have seen distance runners with this injury. While a rare injury in distance runners, with the recent increase in trail running injuries to this area may increase. Trail running will result in more ankle ligamentous injuries than fractures, but the possibility of fracture should be kept in mind.

There are two main classification systems in use for classification of ankle fractures. The more recent one, Danis-Weber, is a simpler, and less useful system than the older Lauge-Hansen fracture classification system. The Danis-Weber system lays out the level at which the injury has occurred: below, at, or above the malleoli. The Lauge-Hansen system uses an arcane and somewhat less than ideal description of foot position and motion of the foot relative to the leg to give a fairly accurate portrayal of the injury and the order in which structures are injured. This system was devised from cadaver studies, but has been found to be an accurate portrayal of fractures in real life. More than 95% of ankle fractures fit the Lauge-Hansen classification scheme.

The simple review here is set up to be used as a quick reference or downloaded, put on your portable device and memorized.

Anatomy: The bones in this area are the distal tibia, distal fibula, talus, and calcaneus. The ligamentous structures include the anterior and posterior talo-fibular ligaments, interosseus ligament, deltoid ligament, anterior talo-fibular ligament, posterior talo-fibular ligament, and calcaneo-fibular ligament.

Occurance: Studies report that up to 15% of ankle injuries result in fracture.

Signs and Symptoms:

History of injury to this area, usually involving a fall. Swelling and ecchymoses in the area of the malleoli. Tenderness over the bone. The patient might not be able to bear weight. These signs lead to the necessity of radiographic examination.

Danis-Weber Classification

The Danis-Weber classification system uses the position of the level of the fibular fracture in its relationship to its height at the ankle joint.

Type A: fracture below the ankle joint
Type B: fracture at the level of the joint, with the tibiofibular ligaments usually intact
Type C: fracture above the joint level which tears the syndesmotic ligaments.

Lauge-Hansen Classification

This classification scheme uses 2 words descriptors. The first word describes the position of the foot, the second word describes the motion of the foot (talus) with respect to the leg. Mentally image this as you learn the sequence staging.

Supination-Adduction

Stage 1: Transverse fracture of lateral malleolus, at or below the level of anterior talo-fibular ligament or a
tear of lateral collateral ligament structures with the anterior talofibular ligament disrupted most often and frequently the calcaneofibular ligament also being torn.

Stage 2: Oblique fracture of medial malleolus.

Supination-External (Eversion) Rotation

Stage 1: Rupture of anterior inferior tibiofibular ligament.
Stage 2: Oblique fracture or spiral fracture of the lateral malleolus.
Stage 3: Rupture of post tibiofibular ligament or fracture of posterior malleolus of tibia.
Stage 4: Transverse (sometimes oblique) fracture of Tibial malleolus.

40% - 70% of all ankle fractures.

Pronation-Abduction

Stage 1: Rupture of the deltoid ligament or transverse fracture of the medial malleolus.
Stage 2: Rupture of the anterior and posterior inferior tibiotalofibular ligaments or bony avulsion.
Stage 3: Oblique fracture of the fibula at the level of the syndesmosis.

Less than 5% of ankle fractures.

Pronation-Eversion

Stage 1: Rupture of the deltoid ligament or transverse fracture of the medial malleolus.
Stage 2: Rupture of the anterior nferior tibiotalofibular ligaments or bony avulsion.
Stage 3: Spiral/Oblique fracture of the fibula above the level of the syndesmosis.
Stage 4: Rupture of the posterior inferior tibiofibular ligament or fracture of the posterior malleolus.

Pronation-Dorsiflexion

Stage 1: Fracture of the medial malleolus.
Stage 2: Fracture of the anterior lip of the tibial.
Stage 3: Fracture of the supramalleolar aspect of the fibula
Stage 4: Rupture of the posterior inferior tibiofibular ligament or fracture of the posterior malleolus.

Useful References:

Osteochondritis Dissecans (OCD) and Osteochondral Defects of the Ankle: Dr. Pribut on OCD

Ankle Sprains: Dr. Pribut on Ankle Sprains - Evaluation, Treatment

For general evaluation and treatment of lateral ankle inversion injuries see: Dr. Pribut on Ankle Injuries

Lauge-Hansen N: Fractures of the ankle: combined experimental-surgical and experimental-roentgenologic investigations. Arch Surg 1950;60(5):957-985

 

... mentally image the position and movement as you learn the staging...