A patient with a proximal tibial fracture in a long leg cast develops marked swelling and severe pain; this is classic for acute compartment syndrome. Which complication may develop if left untreated?

• A. Traumatic arthritis
• B. Malunion of fracture fragments
• C. Osteomyelitis
• D. Volkmann's contracture

Answer: (D)

Acute compartment syndrome can cause irreversible muscle damage if not treated promptly. When pressure rises inside a muscle compartment, blood flow to muscles and nerves is compromised, leading to ischemia. If this elevated pressure isn’t relieved, the affected muscle tissue can die and be replaced by scar tissue. That scar tissue then contracts over time, pulling on surrounding structures and producing a fixed deformity—Volkmann’s contracture. This is the classic late complication of untreated compartment syndrome.

Other options describe problems that arise from different mechanisms (joint surface damage causing arthritis, fracture healing misalignment causing malunion, or infection causing osteomyelitis) and are not direct sequelae of the unresolved high-pressure state in the compartments.