Open wounds occur with calcaneus fracture from direct application of force and from tearing along the medial side of the fracture as the tuberosity displaces laterally. Secondary soft tissue injury can also occur from pressure of the displaced fracture fragments. Tongue-type fractures of the calcaneus lead to variable amounts of displacement of the posterior tuberosity. This displacement may threaten the posterior soft tissue envelope. Because many calcaneus fractures are splinted initially and immobilized for several weeks until swelling resolves, failure to acutely recognize the potential for posterior skin breakdown may lead to severe soft tissue morbidity. The purpose of this study was to determine the incidence of posterior skin involvement in tongue-type calcaneus fractures and to determine the patient and fracture characteristics that lead to high-risk situations.

University level I trauma center.

All tongue-type calcaneus fractures treated at 1 institution between 2002 and 2007 were identified from a trauma registry. Of 954 patients with calcaneal fractures, 139 tongue-type calcaneus fractures in 127 patients formed the study group.

Patient demographics, comorbidities, injury mechanism, fracture displacement, and time to presentation were evaluated. Those injuries that were associated with posterior, secondary soft tissue breakdown were identified and compared to those without breakdown.

Univariate analysis and stepwise multinomial logistic regressions were used to identify significant predictors of posterior soft tissue compromise.

Twenty-nine fractures (21%) had some degree of posterior skin compromise at presentation, including 12 with threatened skin, 10 with partial thickness breakdown, and 7 with full thickness breakdown. Six soft tissue coverage procedures and one amputation resulted. Patients with posterior skin compromise were less likely to have a fall mechanism (P = 0.001), had significantly greater fracture displacement (P = 0.007), were more likely to smoke (P = 0.039), and were more frequently referred on a delayed basis (P = 0.007). Those with threatened posterior skin who were treated emergently with percutaneous reduction did not progress to soft tissue compromise.

A high incidence (21%) of posterior skin compromise occurs in tongue-type calcaneus fractures. These should be treated with immediate reduction, plantarflexion splinting, and close monitoring. Although mechanism, displacement, and time to presentation were significantly correlated with posterior skin involvement, the surgeon should be aware of this potential complicating factor in all tongue-type fractures.