The arm is kept in place in the shoulder socket by the rotator cuff, a group of muscles and tendons that form a covering around the head of the upper arm bone and attach it to the shoulder blade.
The rotator cuff is a frequent source of pain in the shoulder. Tendonitis in the shoulder occurs when rotator cuff tendons become irritated or damaged.
Early symptoms of tendonitis in the shoulder may be mild and may feel like:
- Minor pain present both with activity and at rest
- Pain that radiates from the front of the shoulder to the side of the arm
- Sudden pain with lifting and reaching movements
- Athletes in sports that use their arms overhead may have pain when throwing or serving
Other symptoms of tendonitis in the shoulder may feel like:
- Pain and stiffness when lifting the arm
- Pain when the arm is lowered from an elevated position
- Local swelling and tenderness in the front of the shoulder
- Pain at night
- Loss of strength and motion
- Difficulty performing activities that require placing the arm behind the back, such as zipping clothing
What Causes Tendonitis in the Shoulder?
Tendonitis in the shoulder (rotator cuff pain) commonly occurs in both young athletes and middle-aged people.
Causes of rotator cuff irritation or injury include:
- Athletes who use their arms overhead for swimming, baseball, and tennis
- People who do repetitive lifting or overhead activities using the arm, such as paper hanging, construction, or painting
- Minor injury to the shoulder
How Is Tendonitis in the Shoulder Diagnosed?
Tendonitis in the shoulder is diagnosed with a patient history and physical examination of the shoulder that may include tests to assess range of motion and strength.
Tests used to help diagnose tendonitis in the shoulder include:
- X-rays
- These do not show soft tissue so they are often normal
- Magnetic resonance imaging (MRI) scan
- MRIs create better images of soft tissues such as tendons
What Is the Treatment for Tendonitis in the Shoulder?
It is important to see a doctor for a diagnosis to determine the cause of shoulder pain, because treatment for shoulder pain depends on the cause.
Treatment for tendonitis in the shoulder may include:
- Rest
- Activity modification
- Pain medicines
- Physical therapy
- Focus is on restoring normal motion to the shoulder
- Stretching exercises to improve range of motion are performed at first
- Then, strengthening exercises for the rotator cuff muscles are added
- Steroid injections
- If rest, medications, and physical therapy do not relieve the pain, injections may be used to help reduce pain and inflammation
- Surgery, if nonsurgical treatment does not relieve pain
- Arthroscopy in which bone on top of your shoulder (acromion) may be removed with some of the bursa, which is lubricating sac between the rotator cuff and the acromion
- Rehabilitation following surgery
- Arm may be in a sling
- Exercises to regain should range of motion and strength
- Typically takes two to four months for pain relief but can take up to one year
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https://orthoinfo.aaos.org/en/diseases--conditions/shoulder-impingementrotator-cuff-tendinitis
https://www.uofmhealth.org/health-library/tp23002spec