Bing Hu MD, Presenter: Nothing to Disclose

Tetyana A. Gorbachova MD, Abstract Co-Author: Nothing to Disclose

Peter S. Wang MD, Abstract Co-Author: Nothing to Disclose

Jay C. Horrow, Abstract Co-Author: Research Consultant, Johnson & Johnson Research Grant, Merck & Co, Inc

Several patterns of marrow edema in the ankle have been identified in setting of acute trauma. We encountered a distinct pattern of focal bone bruising and osteochondral fractures of the plantar aspect of the talar head that has not been previously studied. The purpose of this study is to examine the relationship between bone bruises and/or osteochondral fractures of the plantar aspect of talar head and other ligamentous and osseous abnormalities on ankle MRI and to hypothesize a mechanism of injury.

A database search was performed from January 2009 to December 2013 providing a total of 589 ankle MRI studies with osseous injuries. Retrospective review of these cases yielded 37 cases of bone bruises and/or osteochondral fractures involving the plantar aspect of the talar head. Cases of diffuse midfoot marrow edema, diffuse talar head edema, talar osteonecrosis, calcaneonavicular coalition, gross talar fractures, inflammatory arthropathy, and infection were excluded. Osseous and ligamentous structures were evaluated by two radiologists in consensus.

Injuries of the plantar aspect of the talar head have a high association with other concurrent osseous injuries, 86% (32/37), most commonly involving the anteromedial (68%) and posteromedial talar body (49%), and medial malleolus (43%). There is a high prevalence of lateral ankle ligamentous sprain (76%) with multiligamentous injury seen in 51%. Spring ligament was injured in 14%. Strain or avulsion of the extensor digitorum brevis muscle was seen in 27%. 5 of 9 patients age 16 and below had Salter-Harris type fractures of the distal fibula.

Injury of the plantar talar head has a high association with medial sided bone contusions and lateral ligamentous sprains, which suggests an inversion mechanism of this injury. A higher prevalence of multiple bone contusions and multiligamentous sprains also indicates a greater severity of injury in this cohort.

Plantar talar head contusions and osteochondral fractures suggest more severe ankle injury that should prompt search for concurrent osseous and ligamentous injuries. In adolescents, they can be associated with Salter-Harris type injury to distal fibula.

Hu, B, Gorbachova, T, Wang, P, Horrow, J, Plantar Talar Head Contusions and Osteochondral Fractures: A Predictor of Ligamentous and Osseous Injury in Ankle Trauma?.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14015074.html