Joint Aspiration (Arthrocentesis)

Joint aspiration, or arthrocentesis, is a procedure where fluid is withdrawn from a joint using a sterile needle and syringe. It is commonly used to diagnose conditions such as gout, infection, or inflammation and may also help relieve pressure and discomfort. The fluid is often sent for lab analysis to guide further treatment. The procedure is typically done in a clinic setting, sometimes with ultrasound guidance for improved accuracy.

Joint aspiration is usually well tolerated and causes only mild discomfort. Local anaesthetic is applied to numb the area, though some pressure or brief stinging may be felt. Post-procedure soreness is common but typically resolves within a day or two. Pain levels can vary depending on the joint, the underlying condition, and individual sensitivity. If pain persists or worsens after the procedure, consult your orthopaedic specialist promptly to rule out complications.

Recovery from joint aspiration is usually quick, with most people resuming light activities the same day. Mild soreness or stiffness may occur and typically resolve within one to two days. If a corticosteroid is injected, your doctor may advise limiting activity for up to 24 hours. If pain worsens, swelling increases, or mobility is affected after the procedure, a prompt medical review is recommended to rule out infection or other complications.

Joint aspiration may be considered if a joint is persistently swollen, painful, or inflamed without a clear cause. It helps diagnose underlying issues such as infection, gout, or inflammatory arthritis and can relieve pressure. Because untreated joint swelling may worsen or indicate a serious condition, it should be assessed by a doctor or orthopaedic specialist to determine whether aspiration is appropriate and to guide further management based on clinical findings.

General anaesthesia is not used for joint aspiration. The procedure is performed with the patient awake, using local anaesthetic to numb the area and minimise discomfort. It is typically completed in a clinic and does not require hospital admission or sedation. While some discomfort may occur, most people tolerate the procedure well.

There is no fixed limit to how often a joint can be aspirated, but frequency depends on the underlying condition, response to treatment, and risk of complications. Repeat aspirations may be used to manage recurrent swelling, though repeated procedures may increase the risk of infection or tissue irritation. It is best to discuss with your doctor whether ongoing aspiration is suitable for your condition or if alternative treatment should be considered.

Walking is usually possible after a knee aspiration, especially if no medication is injected. Light activity is generally safe, though rest is recommended for several hours post-procedure. If a corticosteroid is injected, reduced activity may be advised for up to 24 hours. Always follow the specific instructions provided by your knee specialist, and seek medical attention if pain worsens, swelling increases, or walking becomes difficult after the procedure.

Cortisone injections may feel more painful in smaller joints like the fingers, toes, or wrists due to limited space and increased nerve sensitivity. Larger joints such as the knee or shoulder are often better tolerated, especially with the use of local anaesthetic and ultrasound guidance. While discomfort is usually brief, pain perception varies from person to person and may also depend on the degree of underlying inflammation in the joint.

A knee may need to be drained of synovial fluid if it becomes swollen, painful, stiff, or warm without a clear cause. Joint aspiration can help diagnose conditions such as gout, infection, or internal bleeding and may also relieve pressure. Since untreated knee swelling can worsen or indicate a serious condition, it should be promptly assessed by a knee specialist to determine if aspiration is appropriate and to guide further treatment.

Driving is generally allowed after joint aspiration if movement and reflexes are unaffected. Rest is usually recommended for several hours, especially if the knee is involved or medication has been injected. If discomfort, stiffness, or reduced mobility is present, driving may need to be postponed. Always consult your orthopaedic specialist and follow their instructions regarding when it is appropriate to resume driving after your joint aspiration.

Joint aspiration is not considered a surgical procedure. It is a minimally invasive technique that involves inserting a needle into the joint to withdraw fluid, usually under local anaesthetic. The procedure is typically done in an outpatient clinic without the need for general anaesthesia or incisions.

If knee fluid is not assessed or treated, symptoms such as swelling, pain, or reduced mobility may persist or worsen. Underlying conditions like infection, gout, or inflammatory arthritis can also lead to joint damage if not managed in time. Because these causes vary in severity, unexplained or ongoing knee swelling should be evaluated by a doctor or knee specialist to prevent complications and guide appropriate treatment.

Joint fluid colour can provide clues about the underlying condition. Clear or pale yellow fluid is typically normal. Cloudy or opaque fluid may suggest inflammation or infection, while red or bloody fluid could indicate trauma or bleeding into the joint. Green or thick fluid is uncommon but may occur with certain infections. Interpretation of fluid colour is typically supported by laboratory testing to confirm the diagnosis.

Joint aspiration is commonly performed by orthopaedic doctors, sports medicine doctors, rheumatologists, or general practitioners trained in joint procedures. In some cases, interventional radiologists or emergency doctors may perform the procedure, particularly when ultrasound guidance is required. The appropriate specialist depends on the joint involved, the suspected cause, and whether the aspiration is intended for diagnosis, treatment, or both.