Injury which develops after long-term or repeated low dose exposure to an air pollutant expressed as chlorosis, bronzing, premature senescence, reduced growth, etc.[1] Fin. Swe.

an injury that may have occurred weeks, months or years in the past

A long-term injury. Classified as chronic after swelling subsides 4 to 5 days after the injury occurs, but pain still persists. Ice therapy is useful in controlling chronic pain and swelling. It may also be used as part of alternating heat/cold therapy during the chronic stage of an injury.