Calcific Tendinitis of the Shoulder

Rotator cuff anatomy relevant to calcific tendinitis:

The supraspinatus tendon is most commonly affected (70-80% of cases), followed by infraspinatus (20%), teres minor, and subscapularis (rare).

Critical zone of supraspinatus:

• Located 1-2cm from the greater tuberosity insertion
• Area of relative hypovascularity
• Watershed zone between osseous and tendinous blood supply
• Site where calcium deposits typically form

Pathophysiology:

• Cell-mediated process (not degenerative)
• Chondrocyte metaplasia of tenocytes
• Calcium hydroxyapatite crystal deposition
• Unknown trigger but associated with hypoxia

Anatomical factors:

• Tendon compression between acromion and humeral head
• Repetitive microtrauma
• Impingement may coexist

Conservative treatment complications:

• Prolonged symptoms (rare, condition usually self-limiting)
• Frozen shoulder (may develop secondary stiffness)
• Chronic pain if resorption does not occur

Barbotage complications:

• Post-procedure pain flare (common, 24-48 hours)
• Infection (rare, less than 0.1%)
• Neurovascular injury (rare with proper technique)
• Incomplete calcium removal

Surgical complications:

• Rotator cuff tear (iatrogenic during debridement)
• Incomplete excision (residual calcium)
• Infection (less than 1%)
• Stiffness/frozen shoulder (2-5%)
• Failure to improve symptoms

Recurrence:

• Recurrence is rare (less than 10%) after complete resolution
• More common if calcium incompletely removed during surgery

After barbotage:

• Sling for comfort only (24-48 hours)
• Ice, analgesia (NSAIDs)
• Resume normal activities as tolerated
• Physiotherapy for ROM and strengthening
• Review at 6-8 weeks with repeat imaging

After arthroscopic excision:

If rotator cuff repair performed:

• Standard cuff repair rehabilitation protocol
• No active elevation for 6 weeks
• Sling for 4-6 weeks

Prognostic Factors

Favorable: Resorptive phase (will resolve), soft deposits, smaller size.

Less favorable: Dense formative deposits, large deposits, associated cuff tears.

Global epidemiology

• Radiographic calcific deposits are found in roughly 3-8% of adults, the majority asymptomatic.
• Peak incidence is in the 30-60 year age group, with a female predominance in most cohorts (around 60-65%).
• The supraspinatus is involved in the large majority of cases; bilateral disease occurs in roughly 10-20% and is a negative prognostic marker (Ogon et al, Arthritis Rheum 2009, PMID 19790063).
• Associations reported across populations include diabetes mellitus, thyroid disorders and a possible genetic/metabolic predisposition, although causation is unproven.

Registry and evidence notes

• Calcific tendinitis is a soft-tissue disorder, so it is not tracked by arthroplasty/implant registries (NJR, AJRR, AOANJRR). The strongest evidence base is from RCTs and meta-analyses rather than registries.
• Pooled RCT evidence (network meta-analysis, PMID 27554465) ranks US-guided needling plus subacromial corticosteroid as the preferred non-surgical option, with high-energy ESWT (PMID 14625334) a reasonable alternative.

High- vs limited-resource practice variation

• In well-resourced settings, ultrasound-guided barbotage and high-energy ESWT are widely available and used early for refractory deposits.
• Where musculoskeletal ultrasound or ESWT machines are scarce, management leans on plain radiographs, analgesia, physiotherapy, and image-free subacromial injection, reserving referral for arthroscopy in persistent cases.
• Across all settings the message is the same: counsel patients on the strongly self-limiting natural history before escalating to any intervention.