Joint Injection: Types, Effects and Uses

What Is a Joint Injection?

A joint injection is a minimally invasive medical procedure in which a physician injects a therapeutic substance directly into the joint space. The primary goals are to reduce pain, decrease inflammation, and improve joint function. Joint injections are commonly used to treat conditions such as osteoarthritis, rheumatoid arthritis, bursitis, and sports-related joint injuries.

Indications

Joint injections are used for a wide range of joint-related conditions, including:

• Osteoarthritis (degenerative joint disease)
• Rheumatoid arthritis and other inflammatory joint conditions
• Bursitis (inflammation of the bursa)
• Shoulder impingement and rotator cuff problems
• Tennis elbow (lateral epicondylitis)
• Knee joint pain and meniscus irritation
• Acute sports injuries with joint inflammation

Types of Joint Injections

Corticosteroid Injection

The most common type of joint injection involves corticosteroids (also known as cortisone). These synthetic hormones have powerful anti-inflammatory effects and can rapidly and effectively relieve joint pain. The effects typically last from several weeks to a few months.

Hyaluronic Acid Injection

A hyaluronic acid injection delivers a lubricating substance into the affected joint. Hyaluronic acid is a natural component of joint fluid and helps improve its viscosity and shock-absorbing properties. This treatment is most commonly used for knee osteoarthritis.

Platelet-Rich Plasma (PRP)

PRP injections use processed blood plasma from the patient, concentrated with growth factors. These growth factors are intended to stimulate the regeneration of cartilage and surrounding tissue. Scientific evidence is still growing but shows promising results.

Local Anesthetics

Sometimes local anesthetics are injected alone or in combination with corticosteroids to achieve immediate pain relief. They temporarily block pain signal transmission and allow for rapid mobilization of the joint.

How a Joint Injection Is Performed

The procedure is carried out under sterile conditions. The skin over the affected joint is first disinfected. The physician then inserts a thin needle into the joint space. Ultrasound guidance or fluoroscopy (X-ray) may be used to ensure precise needle placement. The entire procedure typically takes only a few minutes and can be performed on an outpatient basis.

Risks and Side Effects

Joint injections are generally well tolerated but may occasionally cause side effects, including:

• Temporary increase in pain immediately after the injection
• Redness, swelling, or warmth around the joint
• Risk of infection (very rare with proper aseptic technique)
• With repeated corticosteroid injections: cartilage damage, skin atrophy, or elevated blood sugar in diabetic patients
• Allergic reactions to the injected substance (very rare)

Frequency and Recommendations

The number of injections per joint should be limited. Medical guidelines generally recommend no more than three to four corticosteroid injections per year into the same joint to avoid cartilage damage. The treating physician will determine the most appropriate therapy and frequency on an individual basis.

References

1. American College of Rheumatology (ACR) - Guidelines for the Management of Osteoarthritis of the Hand, Hip, and Knee (2021)
2. Arden NK et al. - Intra-articular glucocorticoid injections in the management of knee osteoarthritis: clinical evidence and strategies for treatment. PubMed (2021)
3. Trojian T et al. - Corticosteroid Injections for Joint and Soft Tissue Injuries. American Family Physician (2021)