Ankle Syndesmosis: A Qualitative and Quantitative Anatomic Analysis

SLR - March 2015 - Kevin M Renner

Reference: Williams, BT, Ahrberg AB, Goldsmith MT, Campbell KJ, Shirley L, Wijdicks CA, LaPrade RF, Clanton TO. Ankle Syndesmosis: A Qualitative and Quantitative Anatomic Analysis. Am J of Sports Med. 2015 Jan;43
(1):88-97.

Scientific Literature Review

Reviewed By: Kevin M Renner, DPM
Residency Program: Grant Medical Center

Podiatric Relevance: This article analyzes and establishes detailed information regarding the anatomy of the syndesmotic ligaments. Currently a limited amount of information exists describing the anatomic characteristics of the syndesmosis regarding the length, orientation and footprint areas. Given the frequency of injury and need for surgical treatment, a more comprehensive anatomical understanding can help surgeons more accurately diagnose and treat these injuries. The hypothesis of the study was that the origins, insertions, footprint areas, ligament lengths, and spatial orientation could be consistently defined for all three syndesmotic ligaments.

Methods: Sixteen fresh-frozen cadaveric specimens were used in the study. Dissection identified both the anterior inferior tibiofibular ligament (AITFL), posterior inferior tibiofibular ligament (PITFL), interosseous tibiofibular ligament (ITFL) and relevant boney structures. The syndesmotic ligament attachments, lengths, footprints, and relevant osseous landmarks were collected using a three-dimensional coordinate measuring device.

Results: The syndesmotic ligaments were found in all specimens. The AITFL had a range of 3-5 bands, collectively it was trapezoidal in shape. The tibial footprint center was 9.3 mm superior and medial to the anterolateral tibial plafond. The fibular footprint center was 30.5 mm superior and anterior to the tip of the lateral malleolus. The PITFL also had a trapezoidal appearance. Its superficial fibers attached broadly along the Volkmann tubercle and blended medially across the posterior surface of the tibia. The centers of the tibial and fibular footprints were 8.0 mm from the posterolateral corner of the tibial plafond and 26.3 mm from the tip of the lateral malleolus. The deep fibers (inferior transverse tibiofibular ligament) were denser with an oval attachment shape. The tibial attachment site was 8 mm distal, medial and anterior to the superficial site and coursed parallel to it. It attached 7.8 mm anterior and distal to the superficial attachment. The ITFL was a pyramidal network of fibers originating 49.4 mm and terminating 9.3 mm proximal to the central aspect of the tibial plafond.
 
Conclusions: Syndesmotic injuries are very common in the foot and ankle surgeons practice. Understanding the detailed anatomy of these injuries is vitally important for proper treatment and surgical planning. The qualitative and quantitative anatomy of all three syndesmotic ligaments were reproducible and consistently defined. Localized osseous references may help optimize diagnostic imaging and surgical techniques and provide data for the development of anatomic reconstruction.