Two-slice-touch rule (knee MRI)
Citation, DOI & article data
The two-slice-touch rule is a sign on MRI of the knee used to increase the sensitivity of diagnosing meniscal tears.
This rule states a meniscal tear is present if abnormal findings are present on two or more images - these do not have to be contiguous, e.g. can occur on sagittal and coronal slices but at the same anatomical location. The only exception to this rule applies to a meniscal root tear, for which abnormal signal in only one slice is considered highly specific for an underlying tear. A possible meniscal tear is present if abnormal findings are present on only one slice in other types of meniscal tear.
- 1. De Smet AA, Tuite MJ. Use of the "two-slice-touch" rule for the MRI diagnosis of meniscal tears. AJR Am J Roentgenol. 2006;187 (4): 911-4. doi:10.2214/AJR.05.1354 - Pubmed citation
- 2. De Smet AA. How I diagnose meniscal tears on knee MRI. AJR Am J Roentgenol. 2012;199 (3): 481-99. doi:10.2214/AJR.12.8663 - Pubmed citation