Grey cortex sign (stress fracture)
Citation, DOI & article data
The grey cortex sign was described as an early sign of stress (fatigue) fractures on plain radiographs and refers to subtle ill-definition/lucency of the cortex at the site of microfracture. However, plain radiography is insensitive (~25%, range 15-25%) for the detection of early-stage injuries. CT is much more sensitive for the detection of bone loss that precedes true fracture 1, however, MRI is the most sensitive/specific modality for the diagnosis of fatigue fractures 4.
- 1. Gaeta M, Minutoli F, Scribano E, Ascenti G, Vinci S, Bruschetta D, Magaudda L, Blandino A. CT and MR imaging findings in athletes with early tibial stress injuries: comparison with bone scintigraphy findings and emphasis on cortical abnormalities. Radiology. 235 (2): 553-61. doi:10.1148/radiol.2352040406 - Pubmed
- 2. Mulligan ME. The "gray cortex ": an early sign of stress fracture. Skeletal radiology. 1995;24:201-3. Pubmed
- 3. Daffner RH. Anterior tibial striations. AJR. American journal of roentgenology. 143 (3): 651-3. doi:10.2214/ajr.143.3.651 - Pubmed
- 4. Marshall RA, Mandell JC, Weaver MJ, Ferrone M, Sodickson A, Khurana B. Imaging Features and Management of Stress, Atypical, and Pathologic Fractures. (2018) Radiographics : a review publication of the Radiological Society of North America, Inc. 38 (7): 2173-2192. doi:10.1148/rg.2018180073 - Pubmed