Hydroxyapatite Deposition Disease/Acute Calcific Tendonitis

Deposition of basic calcium phosphate in the joints and soft tissues leads inflammation; the shoulder is the most frequently involved site ('Milwaukee shoulder')

Aetiology

  • Most common in females, 50-60 years

Pathophysiology

  • Hydroxyapatite crystal deposition in the supraspinatus tendon
  • Release of collagenases, serine proteinases and IL-1
  • Acute and rapid deterioration

Clinical presentation

  • Acute onset of severe shoulder pain

Investigations

  • X-ray - calcification can be seen just proximal to the greater tuberosity
      • notion image

Management

  • NSAIDs, subacromial steriod and local anaesthetic injections for pain relief
  • Usually self limiting - pain eases as calcification resorbs
  • Physiotherapy
  • Surgical removal of calcifications may be appropriate for cases refractory to other attempts of conservative treatment
  • Last line - partial or total arthroplasty