Morphological variations of the deltoid ligament of the medial ankle

Abstract

Morphological variations of the deltoid ligament were investigated in this study, with the aim of classifying the different types on the basis of their components. Sixty ankles from 39 cadavers were dissected. The origin and insertion sites of the deltoid ligament were identified, and its length, width, and thickness were measured. The deltoid ligament was divided into two layers, superficial and deep, which respectively comprised four components (tibionavicular, tibiospring, tibiocalcaneal, and superficial posterior tibiotalar ligaments) and two components (anterior tibiotalar and deep posterior tibiotalar ligaments). The tibiospring and tibiocalcaneal ligaments were found in 100% of the specimens, while the prevalence rates of other components lay within the range 63.3-96.7%. The tibionavicular and deep posterior tibiotalar ligaments were the thinnest and thickest, respectively, while the other ligaments had similar thicknesses. The deltoid ligament was classified into types I-IV according to the combinations of these components: all components were present in type I (48.3%), the tibionavicular ligament was absent in type II (36.7%), only the superficial posterior tibiotalar ligament was absent in type III (6.7%), and only the anterior tibiotalar ligament was absent in type IV (8.3%). In conclusion, these results improve knowledge of the morphological and morphometric characteristics of the deltoid ligament and thus provide helpful information for surgical procedures in this region. Clin. Anat. 29:1059-1065, 2016. © 2016 Wiley Periodicals, Inc.

Evaluation of ankle ligaments with CT: A feasibility study

“…Per patient based comparison of thickness measurements between CT and MRI in our cohort revealed good agreement between the two imaging modalities, with a trend towards larger diameters for CT measurements -especially for the ATFL and TNL -due to partial volume effects of adjacent synovial fluid. Our measurementresults of ligamental thickness were in good accordance with those found in previous studies [9,[28][29][30].…”

“…Contrary to our results the cases series of 8 patients by Gossner [18] described only the ATFL to be constantly and the LFC and PTFL only inconstantly discernible with standard CTwhich maybe explainable by technical limitations due to older 16-slice MDCT-scanner generations used in that study. Interestingly our patient cohort showed less ligamental aplasia for the ATTL than reports from other studies [9,28], reflecting the known anatomic variability of this ligament.…”

The undefined anatomical variations of the deltoid ligament bundles: a cadaveric study

“…In our dissections, the dATT ligament was the smallest and thinnest ligament. As reported by Hyung-Jin Won 34 , it was located beneath the TCN and frequently blended with the ankle joint capsule, resulting difficult to isolate except by means of careful dissection under magnification.…”

“…We considered further subdivisions of the TCN artificial and dependant on the dissection performed. TCN seems to play a major role in medial and rotatory stabilization of the ankle joint 8,16 due to its bridging course to the talocrural, talocalcanel and talonavicolar joint and the longer momentum arm compared to the ligament of the deep layer 34 . The tibionavicular part of the TCN ligament seems to restrain the talar head pronation as well as the talonavicular joint medial subluxation, playing an important role in preventing adult flatfoot deformity 34 .…”

“…TCN seems to play a major role in medial and rotatory stabilization of the ankle joint 8,16 due to its bridging course to the talocrural, talocalcanel and talonavicolar joint and the longer momentum arm compared to the ligament of the deep layer 34 . The tibionavicular part of the TCN ligament seems to restrain the talar head pronation as well as the talonavicular joint medial subluxation, playing an important role in preventing adult flatfoot deformity 34 . In agreement with several Authors 6,8,16,33,39 , in our study, the tibiocalcaneal component of TCN was found to be the thickest and strongest of all of the ligaments.…”