Compartment syndrome typically develops within which time frame after injury?

• A. Immediately after injury
• B. Within minutes after injury
• C. Within 6 to 12 hours after an injury
• D. After 24 hours

Answer: (C)

Compartment syndrome arises when pressure within a closed muscle compartment rises after injury due to swelling or bleeding, which then reduces blood flow to the tissues. The buildup of pressure takes some time, so the typical onset is several hours after injury, most commonly within 6 to 12 hours. This window reflects the period it takes for edema or hemorrhage to accumulate enough to impair perfusion. Immediate or minutes after injury and after 24 hours are less typical patterns: the former would require an unusually rapid, massive bleed, while the latter suggests a late presentation with established ischemic injury. Understanding this timing helps guide prompt monitoring and intervention to prevent lasting damage.