A medical connector includes a body having a distal end, a proximal end, and a sidewall extending between the distal end and the proximal end, a helical thread extending radially outward from a surface of the sidewall and comprising a crest portion, flank portions, and a root portion with the flank portions connecting the crest portion to the root portion, and at least one deformable protrusion extending radially outward from the root portion of the helical thread.