What is the earliest indicator of compartment syndrome?

• A. Pain w/ passive ROM
• B. Pain out of proportion
• C. Paresthesias
• D. Pulselessness

Answer: (A)

Rising pressure within a muscle compartment is what drives early ischemia, and the first clue you can reliably detect on exam is pain when the muscles inside the compartment are stretched. Pain with passive movement occurs because extending or moving the involved muscles further increases the internal pressure, quickly triggering sharp, disproportionate pain even before other signs appear. Paresthesias and weakness can come later as nerves and muscle tissue suffer, and a late, less reliable sign is pulselessness, which indicates more advanced compression. So the earliest indicator to recognize and act on is pain elicited by passive range of motion of the affected compartment.