Bimalleolar Ankle Fracture: Medial Plate

Figure 4.1

Initial injury AP and lateral radiographs

The patient underwent closed reduction of the ankle under hematoma block, was placed into a plaster splint, and was scheduled for surgical management.

Treatment Considerations and Planning

The vertical nature of the medial malleolus fracture line lends itself well to fixation with an anti-glide/buttress construct. Usually, a one-third tubular plate is sufficient.

The classic sequence of events in a SAD ankle fracture involves the talus being driven medially against the medial malleolus (Fig. 4.2). This has the potential to cause marginal impaction at the medial tibial plafond [2]. A CT scan of the ankle is often useful in confirming the presence/absence of medial impaction at the articular surface (Fig. 4.3). The impaction may be located at the axilla of the medial plafond or on the medial aspect of the stable distal tibia articular surface (Fig. 4.4). It is important to recognize the marginal impaction in order to address and correct it at the time of surgery. A CT scan can also be useful in identifying the location of the apex of the medial fracture, allowing exact placement of the most optimal surgical incision (Fig. 4.5).

Figure 4.2

Supination-adduction fracture mechanism results in talus being driven medially into the axially of the medial malleolus

Figure 4.3

CT scan of the ankle demonstrating (a) absence of marginal impaction, (b) presence of marginal impaction (**note: b images are from different patient)

Figure 4.4

Marginal impaction seen on AP radiograph (** note: different patient from case example)

Figure 4.5

Identifying the apex (yellow arrow) of the medial fracture in order to plan the surgical approach

Surgical Timing

Most ankle fractures will allow for acute open reduction internal fixation. Delay in medial plating is recommended in instances of extreme significant swelling (without skin wrinkling), local abrasions associated with the injury or haemorrhagic blistering at the site of intended incision due to the concern for the inability to close the surgical incision, or subsequent wound healing and infection issues.

Surgical Tact

Position

The surgery is performed on a radiolucent table with a stack of blankets or a foam block used to create a platform to allow for acquisition of lateral imaging without lifting or manipulating the leg (Fig. 4.6). Patients should be positioned supine with a bump placed under the ipsilateral hip especially if the leg lies in significant external rotation at rest such that the foot points straight up and down. This allows for access to both the medial and lateral sides of the ankle. The authors prefer to use a tourniquet; however this is not mandatory.