Arthrocentesis - Joint fluid aspiration

A joint aspiration, or arthrocentesis, is a procedure which involves using a sterile needle and syringe to drain fluid from the joint. The procedure is also called joint fluid aspiration, joint tap, synovial fluid aspiration, etc. Joint aspiration is typically performed as an in-office procedure.

The most common indication for the procedure is a condition called arthritis – a group of diseases affecting joints or their component tissues. There are several types of arthritis and they can be divided into groups by their clinical course and pathologic appearance.

The four basic types are:

•    inflammatory arthritis
•    degenerative joint disease
•    non-articular rheumatism
•    miscellaneous arthritis

What is the purpose of joint aspiration?

Joint aspiration is used to obtain joint fluid for laboratory examination. The analysis of joint fluid can help define causes of joint swelling or arthritis, such as infection, gout, and rheumatoid disease. In order to do this, doctors test joint fluid for white cell count, crystals, protein, glucose, as well as infection. Joint aspiration can also be helpful in relieving joint swelling and pain, because the removal of joint fluid is also removing the white blood cells which are sources of enzymes that can be destructive to the joint.

In some cases, cortisone medications are injected into the joint during the joint aspiration in order to rapidly relieve joint inflammation and further reduce symptoms.

Results of joint aspiration

Synovial fluid, which is aspirated from the joint, is normally clear and viscous. When it is:

•    Opaque and turbid – it may indicate inflammatory diseases
•    Presence of pus – it may signal septic arthritis cause by some bacteria
•    Blood in the fluid – it may indicate a fracture or blood disorder
•    Crystals in the fluid – it may be signal of gout or pseudogout
•    A high white blood cell count may indicate an inflammatory disorder

There are also various other test which could be done, such as Gram stains for certain bacteria, cultures for infectious organisms, and glucose measurement.

Potential complications

There are several possible complications associated with joint aspiration, although they are very uncommon:

•    local bruising
•    minor bleeding into the joint
•    loss of pigment in the skin

A rare, but serious, complication of joint aspiration is infection of the joint. The condition is then called septic arthritis.

If corticosteroids are injected into the joint, additional, although very uncommon, complications include:

•    inflammation in the joint as a result of the medication crystallizing
•    atrophy or loss of pigment of skin at the injection site
•    increased blood sugar
•    aggravation of preexisting infection somewhere in the body
•    weight gain
•    puffy face and trunk
•    easy bruising

Temporomandibular (TM) disorders

Arthrocentesis is performed by an oral and maxillofacial surgeon. Doctors use needles to withdraw fluid from and inject medication into a joint space. Arthrocentesis of the temporomandibular (TM) joint is used:

•    To treat painful and limited jaw movement or disc displacement that has caused chronic, severe pain.
•    As a diagnostic tool, when there is a need to analyze joint fluid for signs of disease.

Arthrocentesis is done using local anesthetics, with or without a sedative. Sometimes doctor injects the fluid into the joint.     Wash from the joint pain-causing chemicals created by the inflammation process reduces painful pressure or contact between the disc and bone and enlarges the joint space, making it easier to manipulate the joint

After the procedure, nonsteroidal anti-inflammatory drugs (NSAIDs) are used to control pain. After few days, patients are instructed about jaw exercises. In one study, 94% of people with severe closed lock of the temporomandibular joint gained long-term relief from arthrocentesis.

Knee arthritis

Osteoarthritis is the most common type of knee arthritis. This joint disorder is characterized by progressive wearing away of the cartilage of the joint. It typically affects patients over 50 years of age. It is also much more common in patients who are overweight. There is also a genetic predisposition of this condition, because knee arthritis tends to run in families.

Other factors that can contribute to developing knee arthritis include:

•    trauma to the knee
•    meniscus tears
•    ligament damage
•    fractures to the bone around the joint

Knee arthritis symptoms tend to progress as the condition worsens, but not always steadily with time. Often a patient reports good months and bad months, or symptom changes with weather changes.

The most common symptoms of knee arthritis are:

•    Pain with activities
•    Limited range of motion
•    Stiffness of the knee
•    Swelling of the joint
•    Tenderness along the joint
•    A feeling the joint may fall apart
•    Deformity of the joint  

Shoulder and elbow problems

Shoulder pain is an extremely common complaint and many different factors can cause it.
Because arms are so frequently used for so many common activities, shoulder pain can cause significant problems. Some of the most common causes are:

Shoulder Dislocation: A type of injury that occurs when the top of the arm bone (humerus) becomes disconnected from the shoulder blade (scapula). Shoulder dislocations occur also after falls or other serious injuries.

Shoulder Instability: A loose shoulder joint problem; patients may experience symptoms of an unstable joint. This shoulder disorder could be caused by a previous dislocation, or it may happen when the ligaments around the joint are too loose. 

Shoulder Separation: The results of a disruption of the acromio-clavicular joint. This injury can cause pain and swelling of the shoulder.

Hip arthritis

As said before, osteoarthritis is the most common type of hip arthritis, and it is also called wear-and-tear arthritis. This disorder is characterized by progressive wearing away of the cartilage of the joint.

Hip arthritis symptoms tend to progress as the condition worsens. Patients report good months and bad months, or symptom changes with weather changes. 

The most common symptoms of hip arthritis are:

•    Pain with activities
•    Limited range of motion
•    Stiffness of the hip
•    Walking with a limp