Calcaneal Frx: Primary Frx Line   

- Discussion:
    - the primary frx line begins in the sinus tarsi and then extends obliquely and posteriorly to exit the medial wall;
          - hence the frx, travels antero-lateral to posteromedial;
          - the primary frx line usually extends anterior to the angle of Gissane but in some cases may extend anteriorly as far as the calcaneocuboid joint;
    - posteriorly, primary fracture line moves medially, separating the calcaneus into two main fragments;
          - tuberosity fragment is the anterolateral fragment (lateral to center of talus);
          - sustentacular fragment lies medial to the center of the talus;
          - w/ axial loading, the tuberosity moves lateral, and the sustentacular fragment moves medially;
    - primary fracture line may take one of three paths:
          - lateral to posterior facet (from impact on pronated foot)
          - through posterior facet (neutral foot position)
                 - secondary frx line will appear beneath facet, exiting posteriorly and resulting in a tounge type fracture;
          - anteromedial to the posterior facet:
                 - from impact on supinated foot;
                 - primary saggital frx line enters calcaneal sulcus, anteriomedial to posterior facets, & entire posterior facet remains intact;
                 - two part joint depression or tongue frx may result;
    - cautions:
          - radiographs will fail to show the anterior extension of the primary frx line in about one half of cases

Pathoantomy of intra-articular articular fractures of the calcaneus.

Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Wednesday, September 5, 2012 11:27 am