SLR - February 2019 - Bobbi Hayashi

The Role of Calcaneofibular Ligament Injury in Ankle Instability: Implications for Surgical Management

Reference: Hunt KJ, Pereira H, Kelley J, Anderson N, Fuld R, Baldini T, Kumparatana P, D'Hooghe P. The Role of Calcaneofibular Ligament Injury in Ankle Instability: Implications for Surgical Management. Am J Sports Med. 2018 Dec 20:363546518815160. doi: 10.1177/0363546518815160

Scientific Literature Review

Reviewed By: Bobbi Hayashi, DPM
Residency Program: University Hospital, Newark, New Jersey

Podiatric Relevance: Acute inversion ankle sprains are among the most common musculoskeletal injuries in both athletes and nonathletes, which account for 7 to 10 percent of emergency room visits. An estimated 20 percent of severe ankle sprains will lead to chronic ankle instability, diminished athletic performance and further joint injuries [4,7,8,13]. The anterior talofibular ligament (ATFL) and calcaneofibular ligament (CFL) are two of the most important ligaments of the lateral ligament complex injured during inversion injuries of the ankle, the ATFL being the most frequently injured. The standard surgical procedure, first described by Brostrom, is direct repair of the ATFL. It is common practice to repair the ATFL; however, due to inconsistent data with the role of the CFL, it is often deemed unnecessary to repair the CFL. The purpose of this study was to evaluate the effect of CFL injury on ankle joint stability and biomechanics. The hypothesis was that a CFL injury would result in decreased stiffness, decreased peak torque and increased talar and calcaneal motion as well as alteration of ankle contact mechanics when compared with the uninjured ankle and the ATFL-only injured ankle in a cadaveric model.

Methods: Biomechanical testing was performed on a materials testing system of ten matched pairs of cadaver specimens with a pressure sensor in the ankle joint and motion trackers on the fibular, talus and calcaneus. Each specimen was mounted on the testing apparatus in 20° of plantarflexion and 15° of internal rotation. Specimens were axially loaded in compression to full body weight, and each ankle was tested from 0° to 20° of inversion. The ATFL and CFL were then sectioned, and inversion tested was repeated for the following conditions: (1) Intact, (2) ATFL injury and (3) CFL injury. Linear mixed-model regression analyses were used to determine significance for peak pressures, contact area, the inversion ankles of the talus and calcaneus relative to the fibula and the medial displacement of the calcaneus relative to the fibula across the three conditions.

Results: There was significant difference in mean stiffness and peak torque for CFL injury and no significant difference between ATFL injury. Significantly more inversion of the talus and calcaneus as well as calcaneal medial displacement was seen with weightbearing inversion after section of the CFL.

Conclusions: There is a significant difference that suggests that the CFL plays an important role in the stability of both the ankle and the subtalar joints and in tibiotalar contact mechanics. There were several limitations to this study, including, but not limited to, concerns with the use of cadavers and the inability to stimulate complex muscle forces and ground reaction forces that cross the ankle joint and examination of only ATFL and CFL and not posterior talofibular ligament.

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