Why does shoulder bursitis tend to reoccur frequently and be challenging to treat?

Why Shoulder Bursitis Recurs Frequently and Is Difficult to Treat

Shoulder bursitis recurs frequently because the underlying mechanical causes—chronic microtrauma from repetitive overhead activities, rotator cuff pathology, and biomechanical dysfunction—are rarely addressed by standard treatments that focus only on inflammation control. 1, 2

Primary Mechanisms of Recurrence

Persistent Mechanical Irritation

• Chronic microtrauma from repetitive activities is the most common cause of bursitis, and unless the inciting activity pattern changes, inflammation will return after treatment ends 3
• The subacromial-subdeltoid bursa becomes inflamed secondary to ongoing impingement from rotator cuff dysfunction, bone spurs, or abnormal scapular mechanics 2, 4
• Approximately 65.5% of patients with shoulder bursitis have only one associated pathology, but 34.5% have multiple concurrent shoulder problems that perpetuate bursal inflammation even when the bursa itself is treated 2

Underlying Structural Pathology

• Bursitis is frequently associated with acromioclavicular joint arthritis, supraspinatus calcific tendinopathy, rotator cuff tears (both full-thickness and superficial), and trauma—all of which independently cause recurrent bursal irritation 2
• The bursa inflammation often represents a secondary phenomenon rather than the primary disease, explaining why isolated bursal treatment fails 2
• Scapulothoracic dysfunction, glenohumeral joint instability, and muscle atrophy create abnormal motion patterns that continuously re-irritate the bursa 4

Why Standard Treatments Fail

Limitations of Conservative Management

• Complete immobilization should be avoided as it causes muscular atrophy and deconditioning, yet inadequate rest allows ongoing damage 1
• Ice and NSAIDs provide only short-term symptomatic relief without addressing mechanical causes 1
• Bursal aspiration of microtraumatic bursitis is generally not recommended because of the risk of iatrogenic septic bursitis, limiting treatment options 3

Corticosteroid Injection Limitations

• While intra-articular corticosteroid injections (triamcinolone) effectively reduce pain in the short term, the steroid effect is relatively restricted to short-term relief and repeated injections are frequently required, contributing to unwanted side effects including tendon weakening 1, 5
• Subacromial corticosteroid injections work only when pain relates specifically to subacromial region inflammation, but do not address rotator cuff tears, capsular restrictions, or scapular dyskinesis 6
• High-quality evidence demonstrating benefit from intrabursal corticosteroid injections for microtraumatic bursitis is unavailable 3

The Tendinopathy Connection

• Chronic tendinopathy involves collagen disorientation and fiber separation with degenerative changes rather than acute inflammation, meaning anti-inflammatory treatments miss the underlying pathology 1
• Tensile loading stimulates collagen production and guides normal alignment of newly formed collagen fibers, but patients often avoid loading the painful shoulder, preventing healing 1
• Eccentric exercise has proved beneficial in Achilles and patellar tendinopathy and likely helps shoulder conditions, but is rarely prescribed systematically 1

Critical Pitfalls Contributing to Recurrence

Improper Rehabilitation Techniques

• Overhead pulleys encourage uncontrolled abduction and dramatically increase the risk of shoulder pain—this common rehabilitation error perpetuates bursitis 1, 6
• Inadequate staff education about proper handling of the shoulder allows preventable trauma during therapy 1, 6
• Failure to address scapular strengthening, postural reeducation, and core strength endurance allows abnormal mechanics to persist 4

Incomplete Range of Motion Restoration

• External (lateral) rotation limitation relates most significantly to the onset and persistence of shoulder pain, yet stretching programs often neglect this specific motion 1, 7
• Adhesive capsulitis can develop when range of motion exercises focusing on external rotation and abduction are inadequate, creating a vicious cycle of pain and stiffness 1, 7

Missed Concurrent Pathology

• In 30.4% of cases, patients have two shoulder pathologies, and 4.1% have three concurrent conditions—treating only the bursitis while ignoring rotator cuff tears, impingement, or arthritis guarantees recurrence 2
• Imaging studies should be reserved for recalcitrant pain despite adequate conservative management, meaning many underlying structural problems go undiagnosed 1

Evidence-Based Approach to Reduce Recurrence

Address Mechanical Causes First

• Identify and modify repetitive overhead activities or occupational factors causing chronic microtrauma 3, 4
• Implement eccentric strengthening exercises and stretching programs emphasizing external rotation and abduction 1
• Avoid complete immobilization while allowing adequate rest from pain-provoking activities 1

Consider Advanced Imaging When Appropriate

• Ultrasonography is useful for detecting moderate to full-thickness rotator cuff tears and showing tendon thickening and decreased echogenicity in chronic tendinopathy 1, 2
• MRI demonstrates 95% sensitivity and specificity for rotator cuff tears, degeneration, and partial tears that perpetuate bursitis 1
• Reserve imaging for cases with recalcitrant pain despite 6-8 weeks of conservative management 1

Alternative Injection Strategies

• Botulinum toxin type B shows significantly better outcomes than triamcinolone at 3 months for subacromial bursitis, with sustained pain reduction and improved function without the side effects of repeated steroid injections 5
• For spasticity-related shoulder pain, botulinum toxin injections into subscapularis and pectoralis muscles address the underlying muscle dysfunction 6