What is an early warning sign of compartment syndrome?

• A. Severe pain out of proportion to exam, especially with passive stretch
• B. Decreased pulse
• C. Numbness
• D. Fever

Answer: (A)

The main idea here is recognizing that increasing pressure within a muscle compartment causes ischemic pain that is disproportionate to what you see on exam. The most early and telling sign is severe pain that outstrips the exam findings, and it becomes even more pronounced with passive stretching of the involved muscles. This happens because the pressure reduces capillary blood flow and irritates nerves early in the process, so the patient experiences intense pain before other signs.

Pulses can remain present even as pressure rises, so a decreased pulse is not an early indicator and may appear only later. Numbness or tingling can occur as nerves become affected but typically is not the earliest sign. Fever doesn’t relate to compartment syndrome and would point to another issue like infection.