Pyarthrosis is a medical term that denotes a condition characterized by the presence of pus within a joint cavity. It is a type of infectious arthritis that occurs due to the invasion of bacteria into the joint space, leading to the formation of pus. The term "pyarthrosis" is derived from the Greek words "pyo" meaning pus, and "arthrosis" referring to a joint.

In pyarthrosis, the spread of bacteria may occur through direct penetration from an adjacent infected area, such as a wound, or via the bloodstream from a distant site of infection. Common bacteria responsible for causing pyarthrosis include Staphylococcus aureus, Streptococcus, and Escherichia coli.

The condition typically presents with symptoms such as severe joint pain, swelling, redness, warmth, and limited range of motion. Systemic signs of infection like fever and chills may also be present. Prompt diagnosis and treatment are crucial to prevent further joint damage and systemic complications.

Treatment for pyarthrosis generally involves the use of antibiotics to combat the infection. In some cases, surgical intervention may be necessary for drainage of the infected joint fluid and removal of any necrotic tissue. Physical therapy may also be employed in the rehabilitation phase to restore joint function and mobility.

If left untreated, pyarthrosis can potentially lead to joint destruction, chronic pain, and permanent disability. Therefore, early recognition and appropriate management are key to minimizing the impact of this condition on the affected individual's quality of life.