Lateral Malleolus Fracture Treatment

Lateral malleolus fracture treatment options include Kirschner wires, tension band, screws, intramedullary rods or plate.

See Also: Ankle Anatomy

Lateral Malleolus Fracture Treatment Surgery Steps

If the fractured fibula is part of a bimalleolar fracture pattern, the lateral malleolar or fibular fracture is usually reduced and internally fixed before fixing the medial malleolar component, except in the case of a comminuted lateral malleolus as part of a bimalleolar or trimalleolar pattern. In severe cases of comminution, the lateral malleolus may be over-reduced, hindering the anatomical reduction of the medial malleolar component. In such cases, it may be advisable to proceed with medial malleolar fixation initially.

See Also: Lateral Ankle Sprain

To expose the lateral malleolus and the distal fibular shaft, make a lateral longitudinal incision while taking care to protect the superficial peroneal nerve. Alternatively, a posterolateral incision can be used, and the plate can be inserted with a posterior antiglide technique.

See Also: Approach to the Lateral Malleolus

See Also: Posterolateral Approach to Ankle Joint

Lateral Malleolus Fracture Surgery Options

If the fracture is sufficiently oblique, has good bone stock, and no comminution, fix the fracture with two lag screws inserted from anterior to posterior for interfragmentary compression. Place the screws approximately 1 cm apart. The length of the screws is crucial, ensuring engagement with the posterior cortex for secure fixation without protruding far enough posteriorly to encroach on the peroneal tendon sheaths.​

For transverse fractures, an intramedullary device can be used. Split the fibers of the calcaneofibular ligament longitudinally to expose the tip of the lateral malleolus. Insert a Rush rod, interlocking fibular rod, or other intramedullary device across the fracture line into the medullary canal of the proximal fragment. Avoid tilting the lateral malleolus toward the talus as it can lead to narrowing of the ankle mortise and reduced motion. Contour the intramedullary pin to prevent this mistake.

If the fracture is below the level of the plafond, the distal fragment is small, and the patient has good bone stock, use an intramedullary 3.5-mm malleolar screw for fixation. In larger patients, a 4.5-mm lag screw can be used. Alternatively, orient the malleolar screw slightly obliquely to engage the medial cortex of the fibula proximal to the fracture.

In patients with poor bone quality, Kirschner wires can be placed obliquely from lateral to medial through the distal and proximal fibular fragments. These wires can be further secured with a tension band wire.

Anatomical reduction and maintenance of fibular length are crucial aspects of the procedure.

For fractures above the level of the syndesmosis, use a small fragment, one-third tubular plate for fixation after achieving anatomical reduction. In larger individuals or for more proximal fractures, a 3.5-mm dynamic compression plate can be used. Plates can supplement lag screw fixation or span a comminuted segment. Generally, place three cortical screws in the shaft of the fibula above the fracture and two or three screws distal to the fracture. Unicortical cancellous screws are placed below the level of the plafond. If placed posterolaterally, the plate acts as an antiglide plate. Although commercially available precontoured fixed angle distal fibular locking plates provide alternative fixation options distally, they often result in increased hardware prominence.

In cases involving osteoporotic patients or those with poor soft tissue coverage, reduce and stabilize the fracture with Kirschner wires placed obliquely through the distal fibular fragment and into the tibia. Syndesmotic fixation.

Aftercare

To immobilize the ankle after lateral malleolus fracture surgery , a posterior plaster splint is applied in a neutral position and elevated.

If the bone quality is satisfactory and the fixation is secure, the splint can be replaced with a removable splint or fracture boot during the first postoperative visit. Range of motion exercises are initiated, while weight bearing is limited for 6 weeks. After this period, partial weight bearing can commence if the fracture is healing properly and progress accordingly.

However, if skin conditions, bone quality, or other factors impede secure fixation, the fracture requires extended protection. In such cases, the patient is fitted with either a short-leg or a long-leg non-weight-bearing cast, depending on the stability of the fixation. If a long-leg cast is initially used, it can be converted to a short-leg cast after 4 to 6 weeks. Weight bearing on the ankle is strictly prohibited until the fracture shows adequate healing progress (8 to 12 weeks). At this stage, a short-leg walking cast is worn, and weight bearing is gradually increased. The cast is removed once the fracture has fully united.

References & More

1. Campbel’s Operative Orthopaedics 12th edition Book.
2. Lateral approach to the malleoli – AO Foundation
3. McKenna PB, O’shea K, Burke T. Less is more: lag screw only fixation of lateral malleolar fractures. Int Orthop. 2007 Aug;31(4):497-502. doi: 10.1007/s00264-006-0216-6. Epub 2006 Sep 1. PMID: 16947052; PMCID: PMC2267624. Pubmed
4. Coifman O, Bariteau JT, Shazar N, Tenenbaum SA. Lateral malleolus closed reduction and internal fixation with intramedullary fibular rod using minimal invasive approach for the treatment of ankle fractures. Foot Ankle Surg. 2019 Feb;25(1):79-83. doi: 10.1016/j.fas.2017.08.008. Epub 2017 Sep 7. PMID: 29409300. Pubmed