The Deltoid-Spring Ligament Complex: A Scoping Review and New Segmental Classification

The aim of this study is to review the variation in description of the individual bands comprising the deltoid and spring ligaments in anatomical dissection studies and to propose a novel approach to describe the structure. A literature search for cadaveric studies identifying anatomical variations in the deltoid and spring ligament complexes was conducted using PubMed and Medline databases. The inclusion criteria encompassed human cadaveric dissection studies with measurement of individual deltoid and spring ligament bands in the English language and with full-text availability. The following studies were excluded: animal studies, articles describing surgical repair approaches, and radiological assessment studies without cadaveric dissection. The demographic data, parameters of individual components, as well as the morphological structure of individual deltoid bands were summarised. Out of the 18,208 studies from the database search, 11 articles were included in this study. Thirteen additional studies were obtained from the bibliographies, resulting in a total of 24 studies with 528 ankles evaluated. Due to the complexity of their anatomical relationships, the deltoid and spring ligaments should be described as a single entity: the "deltoid-spring ligament complex". Its gross morphology can be described as triangular, trapezoidal, and rectangular. It can be differentiated into the deep deltoid and the superficial deltospring ligament, which are connected. The latter encompasses the superficial deltoid and superomedial part of the spring ligament. The deep plantar ligament and "the inferior spring ligament" are separate entities reflecting their discrete natures and histological differences. The superficial deltospring ligament can be divided into contiguous segments with variable bands (thickening but not true ligaments). Each segment can be clinically assessed en masse. This description can help to clarify the nomenclature.