“…RN compression may occur at multiple levels including: (1) the level of the lateral epicondyle (RN-LE), (2) the posterior interosseous nerve at the level of the radial head (PIN-RH), (3) the posterior interosseous nerve at the level of the supinator (PIN-sup), and (4) the superficial RN (SRN). [9][10][11][12][13][14][15][16][17] Stiff tissue boundaries at the elbow may compress the RN and produce neural thickening. 18,19 In this study, we only considered the RN levels that are reported to be associated with LE, thus the nerve at the level of the spiral groove was not investigated.…”