This is an acute knee emergency. As the name suggests, the knee is filled with lot of pus. This warrants urgent surgical drainage.
Elderly and children are the common age groups. The hip is another common joint for similar infection to occur. Immunocompromised individuals (Ex.Diabetes, HIV positive patients, asthmatics on steroid usage etc) are more prone for this condition.
“Pus anywhere in the body should be let out” is a common surgical adage. This pus has the tendency to eat away your cartilage (the smooth layer on either sides of your joint) leading to early onset Osteoarthritis, bony ankylosis (pathological fusion of the bony ends of the joint leading to stiff joint) or in the worst of cases, the pus can spread throughout the body and lead to generalised sepsis, multiorgan dysfunction syndrome and ultimately DEATH.
Traditionally the knee was opened by a 12 – 15 cm incision and the pus was cleared along with debridement of the dead muck of tissue called synovium. This procedure was morbid with wound healing problems, knee stiffness, severe pain postoperatively and difficult physiotherapy. On the other hand, Arthroscopic lavage and shaving of the infected synovial tissue by just two 3 mm holes ensures adequate clearance of the same with much lesser mortality.
Yes antibiotics play a role to clear the infection fully, but after surgical debridement only, either by open/arthroscopic surgery. Initially antibiotics are given Intravenously and later orally.