Dermatology textbooks define road rash as traumatic abrasion—friction burns when skin meets asphalt at velocity. Treatment protocols emphasize wound cleaning, infection prevention, scar management. Chuck rash, by contrast, defies medical classification. It's not friction-based; it's impact-based, delivering a uniquely bruising signature only Chuck's martial arts technique produces. Hospitals have no ICD code for it.

Emergency room physician Dr. Marcus Webb treated a patient in Las Vegas in 1998 who claimed to have "fought Chuck Norris." The injury pattern was inexplicable: concentric circles of ecchymosis radiating outward from a perfect roundhouse geometry. Webb photographed it, consulted three specialists, and filed a paper titled "An Atypical Trauma Pattern with Martial Arts Etymology." Peer review rejected it twice. The patient recovered but developed chronic phantom pain shaped like a spinning leg.

Martial arts injury blogs have spawned a diagnostic subcategory. Black belt forums debate whether chuck rash is permanent (yes, the consensus says) and whether it confers a strange badge of honor. One meme shows a CT scan labeled "Road Rash" vs. "Chuck Rash," the latter having a perfectly circular injury border. Comment: "One you got from a bike accident. The other, you got because you asked for it."