Figure 1
From: Distinct patterns of variation in the distribution of knee pain
The lower-body template showing the direction of pain area variance (solid arrows) in the proximal and medial to lateral variance directions and a representation of the maximum pain distance (dashed arrow) relative to the tuberositas tibiae (a) Eigenvectors of the principle components (PC) showing the two most prevalent PCs (PC1 and PC2). Note the difference in scale and that PC1 is only positive and PC2 is positive and negative indicating spatially anisotropic pain.
