Common causes of osteomyelitis

The responsible organism and route vary with age, health conditions, wound history, body site, and recent procedures, so testing guides treatment.

Bloodstream spread can carry microbes from an infection elsewhere in the body into bone. Contiguous spread starts in nearby skin or soft tissue, such as a deep pressure injury or foot ulcer. Direct inoculation can follow an open fracture, penetrating injury, orthopaedic operation, or infection around implanted hardware.

Reduced circulation, poor wound healing, loss of protective sensation, and impaired immune defences can make infection harder to contain. Osteomyelitis may be sudden, with fever and focal pain, or develop more quietly around a chronic wound. Pain and swelling are presentations of osteomyelitis, but those symptoms also have many non-infectious causes.

A clinician examines the painful area and any wound, reviews previous operations and antibiotics, and may order blood tests and imaging. Blood cultures or a carefully obtained bone or deep-tissue sample can identify the organism and help select an antibiotic. A superficial wound swab may not show what is infecting the bone.

Treatment can involve antibiotics, drainage, removal of dead or infected tissue, wound care, and management of circulation or glucose problems. Hardware is assessed for stability and involvement. Do not use leftover antibiotics, because an unsuitable drug can delay useful sampling and may not reach the responsible organism.

Seek prompt assessment for persistent focal bone pain with warmth, swelling, redness, fever, drainage, or a wound that exposes deep tissue. The threshold should be low after an open fracture or orthopaedic operation, or when an ulcer overlies a bony area.

Go to urgent care for confusion, faintness, rapid breathing, severe weakness, rapidly spreading redness, a cold or discoloured limb, or pain that escalates quickly. These features can signal a spreading infection or threatened circulation.

Ask how the infection may have reached the bone, whether a deep sample is needed before antibiotics, and what imaging can show. Also clarify whether surgery or hardware management is being considered, how wound healing will be supported, and which changes should trigger an earlier review.