Boy With Pain, Swelling, and Skin Discoloration on Injured Forearm

HISTORY
A 6-year-old boy presents in the emergency department (ED) after falling on his right arm. Forearm swollen; no radiographic evidence of fractures or dislocation. Soft tissue injury was diagnosed, and the child was discharged. Parents advised to use cold compresses on the arm and to give the child acetaminophen as needed.

The next day, the boy again presented to the ED with increasing pain, swelling, and skin discoloration over the right forearm.

PHYSICAL EXAMINATION
Prominent swelling and discoloration at dorsal aspect of proximal right forearm with blistering. Forearm tender to palpation; warm to touch. No neurologic deficit. Digital pulses intact. Full range of motion observed at the elbow, wrist, and fingers. No lymphatic streaking or axillary lymphadenopathy noted. Other examination results normal.

LABORATORY STUDIES
Normal white blood cell count and differential. Results of blood cultures negative. No radiographic evidence of fractures or gas in the soft tissue planes of the right forearm. No ultrasonographic evidence of fluid collections or cavities.

WHAT’S YOUR DIAGNOSIS?
(Answer on next page.)

WHAT’S YOUR DIAGNOSIS?
ANSWER: FROSTBITE

Cellulitis or possible necrotizing fasciitis was initially suspected, and a surgical consultation was therefore requested. Further questioning revealed that the child had fallen asleep with a freezer ice pack on his forearm. He awoke in the middle of the night with increased pain at the site. His parents removed the ice pack and gave him acetaminophen. When he awoke the next morning, swelling and bluish red discoloration had developed over the dorsum of the forearm. The cause was frostbite from continuous application of an ice pack to the site.

The child was admitted to the hospital for 24 hours of observation and was followed by a surgical team. His symptoms subsequently resolved completely without additional treatment and medications.

Cold therapy is a well-known and widely used modality during the first 48 hours following a soft tissue injury. There are only a few published case reports of frostbite caused by inappropriate application of an ice pack or ice chips.^1,2 Information about the correct use of cold compression/ice applications is limited, however. MacAuley³ found that 17 of 45 general sports medicine textbooks included no information on the duration, frequency, and length of cold therapy or on the use of barriers between ice and skin. The author concluded that there is a need for an evidence-based consensus about the appropriate use of ice in acute soft tissue injuries.

The key to proper use of ice packs lies in patient education. The above Box offers some “take-home” points for patients and parents. It is critical that the ice pack be applied for 10 to 20 minutes every 2 to 3 hours⁴; continuous application can exacerbate pain and, as in this case, lead to severe frostbite.