APOLLO HEALTH

Ankle sprains are common! They constitute about 1/4 of all sports-related injuries and most commonly occur during basketball.

Ankle anatomy: the ankle, aka the talocural joint, is described as a mortise. The subtalar joint lies inferior to the ankle joint and is responsible for foot inversion and eversion. The stability of the ankle joint depends on the supporting ligamentous structures (the lateral and medial ankle ligaments) and joint congruency.

There are four main ligaments of the ankle. The most commonly sprained ligament is the ATFL (anterior talofibular ligament) followed by the CFL (calcaneofibular ligament), then the PTFL (posterior talofibular ligament).

Ankle injuries:

• Lateral ankle sprains are the most common and occur while running on uneven terrain, landing from a jump, or stepping in a hole.
• A high ankle sprain, or a syndesmotic ankle sprain, occurs as a result of forced external rotation of a dorsiflexed foot
• Deltoid ligament sprains are rare and usually accompanied by a lateral malleolar fracture or syndesmotic injury
• Ankle injuries do not always occur in isolation:
  • Common fractures that mimic ankle sprains include: lateral and medial malleolar, fifth metatarsal base, calcaneus (anterior process), talus (lateral and posterior process, talar dome), navicular
  • Commonly missed tendon injuries include: Achilles rupture, peroneal tendon tears/subluxation/dislocations, posterior tibial tendon injuries, anterior tibial tendon tears, flexor hallucis longus tendons ruptures
  • Nerve injuries that can occur in severe ankle sprains include: peroneal nerve and tibial nerve injuries
• Ankle injuries are graded based on the number of ligaments injured, degree of ligament tearing (partial vs complete) and amount of swelling and ecchymoses

Ankle exam: your provider may perform the following tests to assess for ankle sprains and instability

• Anterior drawer
• Inversion stress test or talar tilt
• Sulcus sign
• Squeeze tet
• External rotation stress test

Imaging is performed using the Ottawa Ankle Rules, which have 100% sensitivity for detecting fracture.

If radiographs are obtained, examine them closely for fractures that mimic ankle sprains as well as for “flake fracture” of the posterior distal fibular rim (indicating a tear of the superior peroneal retinaculum and peroneal tendon dislocation) and widening of the medial talar facet and medial malleolus (indicating deltoid ligament tear and syndesmotic ligament instability).

There is also the option to perform stress radiographs but this is not required. MRI is most useful for diagnosing chronically sprained ankle and talar dome injuries, peroneal tendon tears, bone bruises, or other ocult fractures. CT is more valuable than MRI in delineating bone or joint pathology

Injury prevention:

• A balanced training program reduces the rate of ankle sprains by one-third to one-half
• Prophylactic bracing of athletes has had mixed efficacy

Injury treatment:

• Ligaments undergo a series of phases during the healing process, and early joint mobilization promotes healing
• Early treatment focuses on limiting soft tissue swelling, which speeds the healing process
• Treatment includes PRICE:
  • Protection: taping, lace up splint, thermoplastic ankle stirrup splint, functional walking orthosis. Protected range of motion in an orthosis is superior to short leg cast immobilization in terms of return of motion, strength, and return to function. Patients should weight bear as tolerated and crutches may be used until pain-free weight bearing is achieved.
  • Rest: length of time to return to sports can range from roughly 11days to 26 weeks, depending on injury grade
  • Ice: early use of cryotherapy has beens hown to enable return to activity more quick
  • Compression: achieved via elastic bandage, felt doughnut, neoprene or elastic orthosis, pneumatic device
  • Elevation: limits swelling to speed ligamentous healing
• Rehabilitation occurs in 5 phases:
  • Acute phase: PRICE
  • Subacute: focus on pain-free range of motion, protect against reinjury and strength loss with isometric exercises
  • Rehabilitation: emphasize joint mobilization and stretching, increasing strength with isotonic and isokinetic exercises, proprioceptive training
  • Functional: focus on sports-specific exercises
  • Prophylactic: prevent recurrence of injury through strengthening and prophylactic support. An 8 week proprioceptive training program has been shown to reduce the rate of recurrence
• In the case of high ankle sprains, treatment depends on whether the mortise is widened or fractured. If the mortis is not widened, protection in a short leg cast or brace for 4 weeks followed by physical therapy is the best treatment option. In the presence of widening, operative repair is required.
  • High ankle sprains result in longer periods of disability, with only 44% of patients having an acceptable outcome at 6 months.
• Nonsurgical treatment is superior to surgical treatment for most cases of ankle sprains. Studies have shown that treatment with ankle orthosis is associated with faster return to work and no difference in joint laxity compared to operative treatment of grade 3 ankle sprains. Another study showed osteoarthritis is more common in patients undergoing operative treatment of grade 3 ankle sprains.

Chronic Ankle Pain and Instability

When treating chronic ankle issues, the first step is to determine if symptoms are related to instability or to pain.

Chronic ankle instability: the ankle is evaluated with a stress radiograph. If positive, surgery is indicated to reconstruct the deficient ligaments. If stress x-rays disprove mechanical laxity, the patient may have functional ankle instability that can be due to deficient neuromuscular control the ankle impaired proprioception, and peroneal weakness. In this case, treatment should be directed towards restoring peroneal tendon strength, ankle motion, and improving ankle proprioception.

Chronic lateral ankle instability is also associated with chondral damage. Other causes of ankle instability that may not be seen on stress radiographs includes rotational instability, subtalar instability, distal syndesmotic instability, and hindfoot varus malformation.

Chronic ankle pain: Common causes of chronic ankle pain include occult fractures, tendon tears, nerve injury, or ankle soft tissue impingement. MRI or bone scan is used to rule out occult fractures. If either test reveals an abnormality, a spot radiograph or CT is useful to further identify the location of the fracture.

Injury to the lateral ankle ligaments can produce scarring of the ATFL and joint capsule, leading to “meniscoid tissue” in the ankle. When this inflamed tissue is pinched at the ankle, this is called anterolateral impingement.

When will I be referred to srugery?

Indications for surgery include multiple episodes of instability, demonstration of instability on stress radiographs, failure of a full course of physical therapy and brace.

Ankle reconstruction procedures are categorized as anatomy or nonanatomic. Anatomic reconstruction attempts to tighten lateral ligaments or transfer tendons in the exact anatomic locations of the ATFL or CFL. Nonanatomic reconstructions use tendon transfers to act as tenodesis. Anatomic is preferred.