Shoulder pain is a widespread issue that affects individuals of all ages. Whether the cause is injury, overuse, arthritis, or an inflammatory condition, shoulder pain can significantly limit day-to-day activities such as lifting, driving, or even sleeping comfortably. In many cases, conservative treatments like rest, physical therapy, or oral medications may not provide sufficient relief. This is where shoulder injections become a valuable and effective solution.

This comprehensive guide explores the various types of shoulder injections, how they work, their benefits and limitations, the conditions they treat, and what patients can expect before, during, and after the procedure.

Understanding Shoulder Anatomy and Common Conditions

Before diving into treatment, it’s crucial to understand the complex structure of the shoulder joint. The shoulder is a ball-and-socket joint formed by the humerus (upper arm bone), scapula (shoulder blade), and clavicle (collarbone). It is stabilized by muscles, tendons, and ligaments, making it one of the most mobile yet vulnerable joints in the body.

Common shoulder problems include:

• Rotator cuff injuries (tears or tendinitis)
  
  

• Frozen shoulder (adhesive capsulitis)
  
  

• Shoulder impingement syndrome
  
  

• Osteoarthritis of the shoulder joint
  
  

• Rheumatoid arthritis or other inflammatory joint diseases
  
  

• Bursitis (inflammation of the bursa)
  
  

• Labral tears
  
  

Shoulder injections are often recommended when inflammation and pain persist despite conventional therapies.

What Are Shoulder Injections?

Shoulder injections involve the precise placement of medication directly into a specific area of the shoulder joint. These injections aim to reduce inflammation, relieve pain, and improve mobility. The type of injection used depends on the underlying condition and the targeted part of the shoulder—whether it’s the joint space, bursa, rotator cuff, or surrounding soft tissues.

The main types of shoulder injections include:

Corticosteroid (Steroid) Injections

Hyaluronic Acid (Viscosupplementation)

Platelet-Rich Plasma (PRP) Injections

Nerve Blocks

Local Anesthetic Injections

Stem Cell Therapy (in experimental or private settings)

Corticosteroid Injections: The Most Common Option

Corticosteroids, often referred to simply as “steroids,” are powerful anti-inflammatory medications. When injected into the shoulder, they reduce swelling, heat, and pain caused by inflammation.

How They Work:

Steroids suppress the immune system’s inflammatory response, easing pressure and discomfort around affected tissues such as the rotator cuff, bursa, or glenohumeral joint.

Benefits:

• Quick relief, often within 24 to 72 hours
  
  

• Especially helpful for rotator cuff tendinitis, frozen shoulder, or bursitis
  
  

• Can delay or avoid the need for surgery
  
  

Limitations:

• Relief is often temporary (weeks to a few months)
  
  

• Repeated injections may weaken tendons or soft tissue
  
  

• Usually limited to 3–4 injections per year
  
  

Steroid injections are typically guided by ultrasound to ensure accurate placement and optimal results.

Hyaluronic Acid Injections: Lubricating the Joint

Hyaluronic acid is a substance naturally found in joint fluid that acts as a lubricant and shock absorber. In arthritic joints, this fluid becomes thinner and less effective.

How They Work:

HA injections replenish the joint’s natural cushioning, making movement smoother and less painful—especially in shoulder osteoarthritis.

Benefits:

• Provides longer-lasting relief (up to six months in some cases)
  
  

• May delay the need for joint replacement surgery
  
  

• Suitable for patients who can’t tolerate steroids
  
  

Limitations:

• Not effective for everyone, especially in severe arthritis
  
  

• Slower to take effect (weeks rather than days)
  
  

• May require multiple injections
  
  

While more commonly used for knees, HA injections can also be beneficial in arthritic shoulder joints.

Platelet-Rich Plasma (PRP) Injections: Regenerative Therapy

PRP therapy is a form of regenerative medicine that uses a concentration of the patient’s own blood platelets, which are rich in growth factors that promote healing.

How They Work:

A small amount of blood is drawn, processed to extract platelet-rich plasma, and injected into the injured part of the shoulder. This can help repair rotator cuff tears, tendinitis, and other soft tissue injuries.

Benefits:

• Natural treatment using the body’s own healing cells
  
  

• May improve tissue healing and reduce pain long-term
  
  

• Fewer side effects compared to steroids
  
  

Limitations:

• Results vary between individuals
  
  

• Often not covered by insurance
  
  

• May take several weeks or months to see improvement
  
  

PRP is especially appealing for athletes and active individuals seeking non-surgical recovery options.

Nerve Blocks: Interrupting Pain Signals

Suprascapular nerve blocks or brachial plexus blocks may be used when shoulder pain is severe and resistant to other treatments.

How They Work:

An anesthetic is injected near the nerve supplying the shoulder to block pain transmission to the brain. This can provide temporary or prolonged pain relief, depending on the medication used.

Benefits:

• Immediate pain relief
  
  

• Helps during diagnostic evaluations or before physical therapy
  
  

• Can be used prior to radiofrequency ablation for chronic cases
  
  

Limitations:

• Temporary (usually hours to a few days)
  
  

• May require repeat procedures
  
  

• Not a curative treatment
  
  

Nerve blocks are beneficial in frozen shoulder cases or in postoperative pain management.

Local Anesthetic Injections: Diagnostic and Therapeutic

Sometimes, local anesthetics are injected into the shoulder to both diagnose and relieve pain. For example, injecting lidocaine into the subacromial space can help determine if pain is caused by impingement or rotator cuff pathology.

Benefits:

• Instant (but short-term) pain relief
  
  

• Helps pinpoint the source of pain
  
  

• Often used in combination with steroids or PRP
  
  

Stem Cell Therapy: Emerging and Experimental

Stem cells harvested from bone marrow or adipose (fat) tissue can potentially regenerate damaged tissue. Though still under investigation, stem cell injections have shown promise in treating rotator cuff injuries and degenerative shoulder joint conditions.

Benefits:

• May promote tissue regeneration
  
  

• Longer-term healing potential
  
  

Limitations:

• High cost