Which condition is most likely to present with a chronic draining fistula from bone?

• A. Chronic osteomyelitis
• B. Acute osteomyelitis
• C. Subacute osteomyelitis
• D. Hematogenous osteomyelitis

Answer: (A)

Chronic bone infections tend to persist and form pathways to drain pus, so a draining fistula from bone is a classic sign of chronic osteomyelitis. Over time, the infection causes areas of dead bone (sequestrum) with surrounding new bone (involucrum), and the body creates a sinus tract to the skin to vent ongoing drainage. That long-standing process is what gives the fistula its chronic character.

In contrast, acute osteomyelitis presents with rapid onset symptoms like fever, significant local pain, and swelling without a long-standing drainage tract. Subacute osteomyelitis can have milder symptoms and may not drain, though it can progress to a chronic state. Hematogenous osteomyelitis describes how the infection reaches the bone (through the bloodstream) and can be either acute or chronic, but the presence of a chronic draining fistula specifically points to chronic osteomyelitis.