Septic arthritis is a painful infection in a joint. The infection can come from germs that travel through your bloodstream from another part of your body. Septic arthritis can also occur when a penetrating injury delivers germs directly into the joint.
Infants and older adults are most likely to develop septic arthritis. Knees are most commonly affected, but septic arthritis also can affect hips, shoulders and other joints. The infection can quickly and severely damage the cartilage and bone within the joint, so prompt treatment is crucial.
Treatment involves draining the joint with a needle or surgically. Antibiotics also are usually needed to treat the infection.