“…99 It is perhaps not coincidental that adventitial cysts of the popliteal vessels, another similarly, poorly understood clin-ical entity, have been shown to have connections to the knee joint. 31,46,62,90,117,129,130,145,180 In his paper on intraneural ganglia, Parkes 155 also observed two cases in which there were ganglia in the adventitia of the ulnar and radial arteries with connections to the wrist joint.…”