Fibulocalcaneal Ligament Injection

Indications and Clinical Considerations

The fibulocalcaneal ligament, which is also known as the calcaneofibular ligament, is susceptible to strain from acute injury from sudden inversion of the ankle, as when stepping off a high curb, or from repetitive microtrauma to the ligament from overuse or misuse, such as in long-distance running on soft or uneven surfaces. Patients with strain of the fibulocalcaneal ligament experience pain anterior and inferior to the lateral malleolus. Inversion of the ankle joint exacerbates the pain. On physical examination, there is point tenderness just below the lateral malleolus. With acute trauma, ecchymosis over the ligament may be noted. Passive inversion of the ankle joint exacerbates the pain. Coexistent bursitis and arthritis of the ankle and subtalar joint also may be present and may confuse the clinical picture.

Plain radiographs are indicated for all patients with ankle pain. On the basis of the patient’s clinical presentation, additional testing may be indicated, including complete blood cell count, sedimentation rate, and antinuclear antibody testing. Magnetic resonance imaging and/or ultrasound imaging of the ankle is indicated if disruption of the fibulocalcaneal ligament, joint instability, occult mass, or tumor is suspected ( Fig. 187.1 ).

FIG. 187.1, A 43-year-old woman with ankle strain. The oblique coronal (angled 50 degrees), fat-suppressed, proton density-weighted (repetition time/echo time, 2800/34) image showed nonvisualization of the hypointense structure between the calcaneus and the fibular malleolus. There were apparent edematous changes of the surrounding soft tissue (arrowheads). The initial interpretation based on plain magnetic resonance imaging findings was calcaneofibular ligament disruption.

Clinically Relevant Anatomy

The ankle is a hinge-type articulation among the distal tibia, the 2 malleoli, and the talus. The articular surface is covered with hyaline cartilage, which is susceptible to arthritis. The joint is surrounded by a dense capsule that helps strengthen the ankle. The joint capsule is lined with a synovial membrane that attaches to the articular cartilage. The ankle joint is innervated by the deep peroneal and tibial nerves.

The major ligaments of the ankle joint include the talofibular, anterior fibulocalcaneal, calcaneofibular, and posterior fibulocalcaneal ligaments, which provide the majority of strength to the ankle joint. The fibulocalcaneal ligament is not as strong as the deltoid ligament and is susceptible to strain. The fibulocalcaneal ligament runs from the anterior border of the lateral malleolus to the lateral surface of the calcaneus ( Figs. 187.2 and 187.3 ).