Hip effusion is swelling of the hip joint caused by an increase in synovial fluid surrounding the joint. The increase in synovial fluid can be caused by a variety of health conditions, infection or injury. The presence of excess synovial fluid is commonly referred to as water on the joint.
Causes in Adults
Hip effusion can be caused by trauma or infection. Gout, osteoarthritis, rheumatoid arthritis, psoriatic arthritis and infectious arthritis can also cause hip effusion.
Causes in Children
Medcyclopaedia states that most paediatric cases are caused by idiopathic transient synovitis (irritable hip syndrome), but effusions are also symptoms of septic and juvenile idiopathic arthritis and may present in various stages of Perthes disease.
The symptoms of hip effusion are a visible or noticeably swollen hip joint, with or without pain. Swelling may be accompanied by stiffness or fever in the joint.
When to See a Doctor
The University of Washington Orthopaedics and Sports Medicine websites says visible swelling of a joint is not normal and advises consulting an orthopaedic surgeon if pain is present. Consult a physician to determine the cause of swelling.
The treatment of joint effusion varies with the diagnosis. The underlying cause will dictate the necessary treatment. Non-steroidal anti-inflammatory drugs (NSAIDs), oral steroids and steroid injections are common forms of treatment.