| What is BCP crystal disease? | Musculoskeletal syndromes two categories (arthritis associated with BCP crystal [osteoarthritis] and calcific periarthritis)
Predominant mineral type seen is carbonated hydroxyapatite.
BCP crystals (similar in composition to both normal minerals found in bone and teeth, and pathologic minerals found in atherosclerotic plaques and calcinosis cutis) |
| How is pathogenesis and risk factors for BCP crystal diseases? | Not fully understood, occur in sites of injury, produce symptoms and mediate tissue damage by several mechanisms including induction of inflammation, biochemical disruption, interaction with CT, producing cytokines in absence of inflammation.
Risk factors include (severe radio damage in OA, CPP crystals, hx of trauma/heavy use [Milwaukee shoulder syndrome], ESRD, CT disease, genetic)
Average age is 72 years. |
| How is clinical presentation of BCP? | Osteoarthritis (similar to typical OA, rapid progression to end-stage disease)
Milwaukee shoudler syndrome (chronic syndrome of shoulder arthritis, loss of function and shoulder pain, older adult pt, especially women, large but non-inflammatory shoulder effusions)
Calcific periarthritis (acute severe pain in single joint/tendon/bursa, large and small joints and spine, may have fever, healthy and middle-aged people, women predominate, shoulder 2.7%, joints appear tender, warm, swollen and erythematous with no joint effusion), self limited attacks weeks to months) |
| How is the different presentation of calcific periarthritis in different joint types? | Large joints (shoulder [ gradual shoulder pain no trauma, pain top or lateral of shoulder radiate to deltoid insertion, increased pain at night inable to move affected shoulder] Hip [rectus femoris pain ad tenderness AIIS, exacerbated by hip flexion, snapping hip syndrome calcific deposits to rectus femorus, glut max pain proximal thigh and glut min pain low back])
Small joints (hand flexor carpi ulnaris, maybe hand tendons, foot MTP1 and symptoms plantar aspect)
Other sites (retropharyngeal in cervical spine onset of neck pain and stiffness with dysphagia and odynophagia) |
| How is physical exam of BCP? | glenohumeral joint effusion, crepitation, and joint instability
Routine laboratory studies are generally normal/
Synovial fluid analysis( Alizarin red S staining for calcium-containing crystals can identify calcium-containing crystals in synovial fluid with ordinary light microscope, orange-red clumps, neither sensitive nor specific for BCP crystals) |
| What are image findings in BCP? | X ray (MSS (Involved shoulder joints, severe joint destruction, cartilage loss, rotator cuff damage)
Periarthritis (extraarticular calcifications near tendons))
US (hyperechoic lesions with acoustic shadow, In the resorptive phase the deposit may appear more fluffy, fragmented, or punctuated) |
