Rockwood, Green, and Wilkins' Fractures, 10e Package

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SECTION ONE • General Principles

A

B

C

E

D

F

Figure 5-4. Essex-Lopresti classification of calcaneus fractures by mechanism of injury. The force of injury ( arrows ) creates a secondary fracture line that creates a joint-depression type fracture pattern ( A–C ) when driven more posterior and into the posterior facet, versus a tongue-type fracture pattern ( D–F ) if the force is directed more axially.

in the coronal plane (Fig. 5-5). The articular surface of the pos terior facet at its widest point is subdivided into four possible fragments according to the medial, central, and lateral third of the overlying talus, plus the sustentaculum. Type I fractures include all nondisplaced (<2 mm) articular fractures (despite number of fracture lines); type II fractures are two-part fractures of the posterior facet; types IIA, B, and C are further descriptors based upon location of the articular fracture line. Type III fractures are three-part fractures and are similarly subdivided into types III AB, AC, and BC based upon the location of the articular fracture lines. Type IV fractures are highly comminuted with often more than four articular fragments. Follow-up studies have revealed that this classification system has utility in not only describing the injury but also aiding treatment decisions and predicting out come. 10,51 Based upon the results of a comparative analysis of 108 fractures, the Sanders classification has been shown to be prog nostic. After a minimum of 10 years, type III fractures treated by open reduction and internal fixation were four times more likely to need a subtalar fusion than type II fractures. 52 Recent studies continue to support the validity of the Sanders Classification. Rao et al. studied 36 patients with 48 displaced intra-articular calcaneus fractures using preoperative CT scans to both grade fractures according to the Sanders classification and to qualify fracture severity. 48 These authors found that fracture energy determined by a CT-based measure of fracture energy pos itively correlated with the Sanders classification. 48 Misselyn et al. in 2018 reported improved interobserver reliability of the Sand ers classification using 3D prints (88% vs. 65% for 2D views). 39

OTA/AO 2018 FRACTURE COMPENDIUM CLASSIFICATION

The OTA/AO classification of fractures represents an interna tional effort involving professional organizations dedicated to orthopaedic traumatology, as well as subspecialty societies in spine, shoulder, adult reconstruction, and thoracic surgery. The 2018 revision 38 included recently published validated classifications: OTA open fracture classification, OTA/AO scap ular classification, Unified Classification of Periprosthetic frac tures, AOSpine Cervical and Thoracolumbar classification, and AOSpine Sacral Fracture Classification, and AOTK Thoracic Surgery preliminary classification of rib and sternal fractures were all added. The OTA/AO classification is a systematic method of assigning an alphanumeric code to a given fracture that can be applied to most of the skeleton. Coding fractures allows for broad data col lection within an institution, between institutions, nationally, and internationally. Uniformly identifying and electronically record ing fracture codes that group similar fractures allows for subse quent analysis of meaningful information, increases the utility of multicenter investigation, and provides a structured learning framework across the skeleton for residents and students. To perform basic classification of fractures of long bones, clinicians must understand and apply basic definitions. These have been modified to some extent in the 2018 compendium. The first question that must be answered is “Which bone is frac tured”? (Fig. 5-6). Next, the observer must identify which part