Using the Equatorial Talar Line as a Radiographic Predictor of Sanders Type 3 and 4 Calcaneus Fractures and Lateral...

Area of Science:

• Orthopedic surgery
• Radiology
• Trauma care

Background:

• Calcaneus fractures are common, with Sanders classification system categorizing severity.
• Distinguishing between Sanders types I/II and III/IV is crucial for treatment planning.
• Lateral wall blowout is a significant complication associated with severe calcaneus fractures.

Purpose of the Study:

• To evaluate the equatorial talar line (ETL) as a radiographic tool.
• To determine the ETL's sensitivity in predicting Sanders type III/IV fractures.
• To assess the ETL's ability to predict lateral wall blowout.

Main Methods:

• Lateral ankle radiographs were analyzed.
• Raters assessed the position of the calcaneal tuberosity relative to the ETL.
• Intraclass correlation coefficient (ICC) and receiver operating curve (ROC) analyses were used for reliability and sensitivity assessment.

Main Results:

• The ETL demonstrated high inter-rater reliability (ICC=1.0) for determining its position.
• The ETL showed strong reliability in predicting Sanders fracture type (overall ICC=0.91).
• ROC analysis indicated good sensitivity for predicting Sanders type III/IV fractures (0.82) and lateral wall blowout (0.81).

Conclusions:

• The equatorial talar line is a reproducible radiographic parameter.
• ETL reliably predicts between less severe (type I/II) and more severe (type III/IV) calcaneus fractures.
• ETL can also predict the presence of lateral wall blowout in calcaneus fractures.