Grey cortex sign (stress fracture)
Citation, DOI and 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