Shoulder Tendonitis Treatment
Shoulder tendonitis — inflammation of the tendons that power and stabilize the shoulder joint — is one of the most common causes of shoulder pain, particularly in adults who perform repetitive overhead activities or who have developed age-related changes in the subacromial space. The two tendons most frequently affected are the supraspinatus tendon (the uppermost rotator cuff tendon, which passes through the narrow subacromial space and is most susceptible to impingement) and the long head of the biceps tendon (which runs through the bicipital groove at the front of the shoulder and is subjected to friction and mechanical wear during overhead and rotational movements). When these tendons become irritated from overuse, impingement, or age-related degeneration, they swell and thicken — producing pain with overhead activity, weakness, and a progressive loss of function that worsens over time if the underlying cause is not addressed. Left untreated, chronic tendonitis can progress to tendon degeneration (tendinopathy) and eventually to partial or complete rotator cuff tears.
Dr. Jonathan Glashow is a board-certified orthopedic surgeon and Clinical Associate Professor of Orthopedic Surgery at NYU Grossman School of Medicine, with a traveling shoulder fellowship under Dr. Charles Rockwood and Dr. Richard Hawkins and fellowship training at the Southern California Orthopedic Institute/UCLA. Shoulder tendonitis is rarely an isolated diagnosis — it typically coexists with subacromial bursitis, impingement, and in some cases early rotator cuff fraying — and Dr. Glashow’s evaluation focuses on identifying the full picture of what is happening in the subacromial space rather than treating the tendon inflammation in isolation. With over 30 years of experience, more than 15,000 procedures, and recognition as a Castle Connolly Top Doctor every year since 2000, he evaluates and treats shoulder tendonitis at his Upper East Side practice in New York City.
Types of Shoulder Tendonitis
Rotator Cuff Tendonitis: Inflammation of one or more of the four rotator cuff tendons — most commonly the supraspinatus — caused by repetitive overhead use, subacromial impingement, or age-related degeneration. The supraspinatus tendon is particularly vulnerable because it passes through the narrow subacromial space and is compressed between the humeral head below and the acromion above during every overhead movement.
Biceps Tendinitis: Inflammation of the long head of the biceps tendon where it passes through the bicipital groove at the front of the shoulder. Biceps tendinitis often occurs alongside rotator cuff tendonitis and impingement, and produces pain at the front of the shoulder that worsens with lifting, reaching, and overhead activity.
Calcific Tendonitis: A specific form of tendonitis in which calcium deposits form within the rotator cuff tendons, producing episodes of intense, debilitating pain during the resorptive phase. For detailed information, see the calcific tendonitis page.
Causes and Risk Factors
- Repetitive overhead activity — swimming, tennis, baseball, painting, construction work
- Subacromial impingement from bone spurs, a hooked acromion, or AC joint arthritis
- Age-related tendon degeneration and reduced blood supply (most common over age 40)
- Poor posture and scapular mechanics that alter subacromial space dynamics
- Sudden increase in overhead activity intensity or volume
- Prior shoulder injury that altered joint mechanics
Symptoms of Shoulder Tendonitis
- Pain in the front, side, or top of the shoulder — depending on which tendon is involved
- Pain that worsens with overhead reaching, lifting, and throwing
- Night pain, particularly when lying on the affected side
- Stiffness in the shoulder, especially in the morning or after periods of rest
- Weakness when raising or rotating the arm
- A painful arc of motion — pain when raising the arm between approximately 60 and 120 degrees
- Gradual onset of symptoms that worsen over weeks to months
Treatment Options
Conservative Treatment: The majority of shoulder tendonitis cases respond well to non-surgical management. Dr. Glashow’s approach includes activity modification (reducing or temporarily avoiding the overhead movements that aggravate the tendon), anti-inflammatory medications, ice, and corticosteroid injections into the subacromial space or bicipital groove to reduce inflammation and pain. A structured physical therapy program is the cornerstone of treatment — focusing on rotator cuff strengthening, scapular stabilization, posterior capsule stretching, and correction of any postural or mechanical contributors to impingement.
Arthroscopic Treatment: When tendonitis has not responded to three to six months of dedicated conservative care — or when imaging reveals structural factors such as bone spurs, a thickened acromion, or associated partial rotator cuff tears that require surgical attention — Dr. Glashow may recommend arthroscopic surgery. The procedure may include subacromial decompression (removing bone spurs and shaving the acromion), bursectomy (removing inflamed bursal tissue), debridement of damaged tendon tissue, and repair of any partial rotator cuff tears found during the procedure. For biceps tendinitis that has not responded to conservative treatment, a biceps tenodesis (reattaching the biceps tendon to the humerus to remove it from the irritated bicipital groove) may be performed.
Shoulder Tendonitis Treatment in New York City
If you are experiencing progressive shoulder pain with overhead activity, night pain, or weakness in your arm that has not responded to rest and anti-inflammatory medications, shoulder tendonitis may be the cause — and identifying the underlying mechanical factors is the key to lasting relief. Dr. Glashow offers comprehensive shoulder evaluation with same-day imaging at his Upper East Side practice. Contact our office to schedule your consultation.
Frequently Asked Questions About Shoulder Tendonitis
What is the difference between tendonitis and tendinopathy?
Tendonitis refers to acute inflammation of a tendon — the early stage where the tendon is irritated and swollen but structurally intact. Tendinopathy refers to a chronic, degenerative condition in which the tendon has undergone structural changes — disorganized collagen fibers, reduced blood supply, and loss of normal tendon architecture — from prolonged overuse or untreated tendonitis. Tendinopathy is more difficult to treat than acute tendonitis because the tendon has moved beyond simple inflammation into actual tissue degeneration. This is why early treatment of shoulder tendonitis — before it progresses to chronic tendinopathy — is important.
Which tendon is most commonly affected by shoulder tendonitis?
The supraspinatus tendon — the uppermost rotator cuff tendon — is the most frequently affected, because it runs through the narrow subacromial space where it is most susceptible to impingement and compression during overhead arm movements. The long head of the biceps tendon is the second most commonly involved, particularly in patients with concurrent rotator cuff disease or impingement.
Can shoulder tendonitis lead to a rotator cuff tear?
Yes — chronic, untreated shoulder tendonitis is one of the primary pathways to degenerative rotator cuff tears. When the tendon remains inflamed and compressed over months to years, the collagen fibers gradually weaken, fray, and eventually tear — first partially, then potentially progressing to a full-thickness tear. This tendonitis-to-tear progression is the most common cause of rotator cuff tears in patients over 40, and it is one of the primary reasons Dr. Glashow emphasizes early treatment of tendonitis before structural damage occurs.
How is shoulder tendonitis diagnosed?
Dr. Glashow diagnoses shoulder tendonitis through a clinical examination that assesses pain location, provocative movements, rotator cuff strength, and impingement signs. X-rays can reveal bone spurs, acromion shape, and AC joint arthritis that may be contributing to impingement. An MRI or ultrasound may be ordered to evaluate the tendon directly — identifying thickening, partial tears, fluid around the tendon, or associated bursitis — and to rule out a rotator cuff tear as the source of symptoms. Same-day imaging is available at his Upper East Side practice.
How long does it take for shoulder tendonitis to heal?
Mild tendonitis treated early with rest, anti-inflammatory measures, and activity modification may improve within two to four weeks. Moderate tendonitis with significant impingement typically requires six to twelve weeks of consistent physical therapy to resolve. Chronic tendinopathy — where the tendon has undergone degenerative changes — may take three to six months of dedicated rehabilitation. The key to successful treatment is addressing the underlying cause (impingement, weakness, poor mechanics) rather than just treating the inflammation symptomatically.
When is surgery needed for shoulder tendonitis?
Surgery is considered when tendonitis has not responded to an adequate course of conservative treatment — typically three to six months of physical therapy, activity modification, and at least one corticosteroid injection — and the patient continues to experience significant pain and functional limitation. Surgery is also recommended when imaging reveals structural causes such as bone spurs or a hooked acromion that are physically impinging the tendon and will not respond to rehabilitation alone, or when a partial rotator cuff tear is discovered that requires repair.
