Ankle Sprains, Ankle Instability, and Syndesmosis Injuries

Assessment

Approximately 70% of all lateral ankle sprains involve isolated anterior talofibular ligament (ATFL) injury. The ATFL is the weakest of the lateral ligament structures and is put under increased stress in the most common mechanism of injury, which is foot supination with heel inversion while the ankle is plantarflexed. Pain and swelling are present followed by bruising, loss of motion, and difficulty walking in more serious cases. The anterior drawer and talar tilt tests signify instability when positive, and this may vary from mild to severe. A classification of lateral ankle sprains related to the severity of injury and magnitude of the above findings has been published and validated for time to recovery ( Table 15.2 ).

Acute lateral ankle sprains are typically treated nonoperatively (see Chapter 14 ) in almost all circumstances. Exceptions to this would include open injuries, large avulsion fractures, or other associated pathology such as dislocating peroneal tendons, an osteochondral fracture or loose body, or a bimalleolar fracture equivalent, which would essentially be a dislocated ankle that tears both medial and lateral ligaments. Among the remaining controversies related to acute lateral ankle sprains is whether to operate when faced with an athlete who clearly has a severe injury with major instability. Varying opinions can still be heard on this topic. Another situation that stimulates discussion over whether to operate is the athlete who has a history of significant prior ankle sprains and then presents with a recurrent severe sprain. This is the situation that requires a thorough discussion with the patient to determine the best course of action, and extenuating circumstances often play a role. In other words, is this the correct time to repair what is clearly chronic lateral ankle instability?

Nonoperative Treatment (see Chapter 14 )

When nonoperative treatment is the chosen course, a comprehensive plan needs to be drafted that includes evidence-based interventions. This includes functional rehabilitation with a supportive ankle brace in Grade I and II injuries, while Grade III injuries are more controversial regarding functional treatment versus a short period of immobilization in a walking boot or short-leg cast for 10–14 days. Additional treatment includes rest, ice, compression, and elevation method (RICE), antiinflammatory medication (if there are no contraindications), physical therapy with supervised early exercise when possible, and crutches, but only when weight bearing is not possible. In this latter situation, it is important to immobilize the ankle in neutral to slight dorsiflexion, or the ankle will naturally assume a plantarflexed position and heal with the ligaments in an elongated state. Improvement in ankle dorsiflexion, increased strength in the kinetic chain, manual therapy techniques, and balance training have all been shown to have evidence-based gains in ankle function and pain. Other treatments with less evidence include laser therapy, dry needling, vascular restriction, electrotherapy, vascular restriction, diathermy, and ultrasound. The majority of patients treated with evidence-supported methods improve relatively quickly. According to the classification of acute lateral ankle sprains as Grade I, II, IIIA, or IIIB, full recovery averages 8, 16, 25, and 39 days, respectively. However, when this is not the case, further evaluation is warranted, particularly in the high-level athlete where time loss is critical.

Operative Treatment

In the situation where surgical repair of the torn ligaments is necessary, it is important to define the tissues and repair them anatomically whenever possible ( Figs. 15.1 and 15.2 ). In the acute situation, the injured tissues typically become immediately evident on opening the skin incision. It is important to assess all local structures including the articular cartilage of the ankle joint, the anterior capsule, the deltoid ligament, the peroneal tendons, and superior peroneal retinaculum. At the same time, the surgeon should be protective of the superficial nerves.

In severe sprains, which are essentially dislocations of the ankle joint, one or more of these structures may be injured and need repair. Ligaments torn in midsubstance are repaired with sutures, while tears off bone or with a bony avulsion are repaired with suture anchors. Newer methods of augmentation of repairs have been introduced and proven to be effective. In cases of acute on chronic tears, tissue quality may be lacking and repair with augmentation may be more critical to obtain adequate stability versus reconstruction with a tendon autograft or allograft or a tendon transfer (see next section). The rehabilitation program in these cases is very important and is outlined in the section on rehabilitation ( Boxes 15.1 to 15.3 and Tables 15.3 to 15.5 ).