The intrinsic subtalar ligaments have a consistent presence, location and morphology

Foot Ankle Surg. 2021 Jan;27(1):101-109. doi: 10.1016/j.fas.2020.03.002. Epub 2020 Mar 6.

Abstract

Background: Chronic subtalar instability is a disabling complication after acute ankle sprains. Currently, the literature describing the anatomy of the intrinsic subtalar ligaments is limited and equivocal which causes difficulties in diagnosis and treatment of subtalar instability. The purpose of this study is to assess the anatomical characteristics of the subtalar ligaments and to clarify some points of confusion.

Methods: In 16 cadaveric feet, the dimensions and locations of the subtalar ankle ligaments were assessed and measured. CT-scans before dissection and after indication of the footprints with radio-opaque paint allowed to generate 3D models and assess the footprint characteristics.

Results: The cervical ligament (CL) had similar dimensions as the lateral ligaments: anterior length 13.9 ± 1.5 mm, posterior length 18.5 ± 2.9 mm, talar width 13.6 ± 2.2 mm, calcaneal width 15.8 ± 3.7 mm. The anterior capsular ligament (ACaL) and interosseous talocalcaneal ligament (ITCL) were found to be smaller structures with consistent dimensions and locations.

Conclusion: This study identified consistent characteristics of the intrinsic subtalar ligaments and clarifies the local anatomical situation. The dimensions and footprints of the intrinsic ligaments of the subtalar joint suggest a more important role of the CL and ACaL in the stability of the subtalar joint. The results of this study are relevant to improve diagnostic tools and offer some guidelines when reconstructing the injured ligaments.

Keywords: Anterior capsular ligament; Cervical ligament; Hindfoot instability; Interosseous talocalcaneal ligament; Ligament reconstruction; Subtalar ligament.

MeSH terms

  • Aged
  • Aged, 80 and over
  • Ankle Injuries / diagnosis*
  • Ankle Joint / diagnostic imaging
  • Cadaver
  • Calcaneus / diagnostic imaging*
  • Female
  • Humans
  • Joint Instability / diagnosis*
  • Ligaments, Articular / diagnostic imaging*
  • Male
  • Subtalar Joint / diagnostic imaging*
  • Tomography, X-Ray Computed / methods*