Infection of ligaments and tendons is rare. Infections of bone or cartilage do occur, usually from the hematogenous spread of a microbe, such as with septicemia or bacteremia. Deeply penetrating trauma is another cause of infection to skeletal system tissues. Bone infection, osteomyelitis, typically occurs by hematogenous spread of a microbe to bone tissue. If this occurs, there is the risk of bone tissue destruction, pain, toxin release into the blood, fever, and dislodgment of septic emboli.
Septic emboli are dangerous because they provide seed other tissues with microbes.
If such emboli lodge in the lungs, local lung reflexes can lead to improper ventilation and blood oxygenation. Emboli can also travel to the heart and lodge in coronary arteries that supply heart tissue, causing heart arrythmias and even death. The skull contains hollow regions called sinuses that drain secretions to the respiratory system nasal and pharyngeal cavities. Microbes present in, or introduced into, these respiratory system cavities can find their way into the sinuses, causing infectious sinusitis. Cartilage has no blood supply and must receive oxygen and other nutrients by diffusion from nearby capillaries.