Foot & Ankle Videos: Instability
- Injuries of the distal tibiofibular syndesmosis are commonly overlooked or mismanaged, and chronic instability is a debilitating condition leading to premature joint degeneration. Several methods of treatment have been described, mainly screw fixation, arthrodesis, or ligament reconstruction. Most clinical evidence is limited to case series, mainly screw fixation, and there is a general paucity of evidence regarding ligament reconstruction, which is considered to be more anatomic and to restore joint biomechanics.
- The use of ankle stress radiographs is common to evaluate ankle instability. However, the majority of the studies report the use of a manual method to apply the stress, increasing radiation exposure to the physician. Furthermore, as reported in other studies, the force applied during the stress may vary between examiners according the strength and experience. In this Technical Note, we describe our preferred method to evaluate ankle instability, either using an inversion or eversion stress, avoiding the necessity of a physician in the radiographic room.
- Arthroscopic lateral ankle ligament reconstruction has been recently advocated. But this technique has not been popularized because of the technical complexity and potential iatrogenic injury. Because the talocalcaneal and calcaneofibular ligaments are extra-articular structures, how to efficiently view and address them is a difficult task. Limited dissection outside the capsule to form a working space is required, but aggressive dissection is harmful for tissue healing although it is helpful for visualization and instrumentation.
- The plantar calcaneonavicular ligament, also known as the spring ligament, is an important static stabilizer of the medial longitudinal foot arch. Compromise of this ligament is a primary causative factor of peritalar subluxation, and it should be repaired in addition to treatment of tibialis posterior tendon abnormalities. Open repair of the ligament requires extensive soft-tissue dissection. The development of the high distal portal for posterior tibial tendoscopy allows repair of the ligament endoscopically.
- Standalone open reduction–internal fixation (ORIF) of unstable ankle fractures is the current standard of care. Intraoperative stress radiographs are useful for assessing the extent of ligamentous disruption, but arthroscopic visualization has been shown to be more accurate. Concomitant arthroscopy at the time of ankle fracture ORIF is useful for accurately diagnosing and managing syndesmotic and deltoid ligament injuries. The arthroscopic ankle drive-through sign is characterized by the ability to pass a 2.9-mm shaver (Smith & Nephew, Andover, MA) easily through the medial ankle gutter during arthroscopy, which is not usually possible with both an intact deltoid ligament and syndesmosis.
- Subtle syndesmotic instability not evident on radiography can result in chronic ankle pain. The diagnosis is uncommon, and arthroscopic evaluation remains the gold standard for diagnosis. Definitive surgical management can be performed at the time of diagnosis. Patients with 2 to 4 mm of diastasis of the syndesmosis or translation can be treated with debridement alone, and patients with 4 mm or more of diastasis or translation can be treated with arthroscopic debridement and reduction followed by percutaneous stabilization.
- In recent years, arthroscopic and arthroscopically assisted techniques have been increasingly used to reconstruct the lateral ligaments of the ankle. Besides permitting the treatment of several comorbidities, arthroscopic techniques are envisioned to lower the amount of surgical aggression and to improve the assessment of anatomic structures. We describe our surgical technique for arthroscopic, two-portal ankle ligament repair using an all-soft knotless anchor, which is made exclusively of suture material.
- Ankle instability is a condition that often requires surgery to stabilize the ankle joint that will improve pain and function if nonoperative treatments fail. Ankle stabilization surgery may be performed as a repair in which the native existing anterior talofibular ligament or calcaneofibular ligament (or both) is imbricated or reattached. Alternatively, when native ankle ligaments are insufficient for repair, a reconstruction of the ligaments may be performed in which an autologous or allograft tendon is used to reconstruct the anterior talofibular ligament or calcaneofibular ligament (or both).
- Lateral ankle sprains are common; if conservative treatment fails and chronic instability develops, stabilization surgery is indicated. Numerous surgical procedures have been described, but those that most closely reproduce normal ankle lateral ligament anatomy and kinematics have been shown to have the best outcomes. Arthroscopy is a common adjunct to open ligament surgery, but it is traditionally only used to improve the diagnosis and the management of any associated intra-articular lesions. The stabilization itself is performed open because standard anterior ankle arthroscopy provides only partial visualization of the anterior talofibular ligament from above and the calcaneofibular ligament attachments cannot be seen at all.