Joint infections + Aspiration

Question 1

Contraindications to joint aspiration

Answer 1

• overlying skin infections or lesions (needle shouldnt pass thru sites of cutaneous infection or skin lesions)
• coagulopathy or use of anticoag medication
• bacteremia
• prosthetic joint

Question 2

therapeutic and diagnostic indications for jt aspiration

Answer 2

• diagnostic evaluation of acute monoarticular or polyarticular arthritis
• establish etiology of joint effusion of uncertain cause
• therapeutic treatment of acute joint effusions (relieve pain)

Question 3

boney landmarks for knee aspiration

Answer 3

needle enters 1-2cm medial or lateral to superior third of patella

procedure:

• position pt supine on stretchor, with knee extended or held in slight flexion
• carefully examine jt and identify patella and entry site

Question 4

boney landmarks for shoulder aspiration

Answer 4

• palpate coracoid process of scapula and humeral head anteriorly to identify point of entry
• needle is inserted INFERIOR and LATERAL to coracoid process and directed POSTERIORLY toward joint space

Question 5

appearance of aspirate and what it means

Answer 5

normal synovial fluid = colorless or amber and trasnparent

inflammatory fluid = amber or yellow and opaque

septic arthritis= grossly purulent

hemarthrosis = grossly bloody fluid

Question 6

lab tests to be performed on aspirate (based on px and appearance of aspirate)

Answer 6

three lab tests:

CBC + diff (normal is <180 WBC/mm3)

crystal analysis

gram stain + culture ** prioritize if septic arthritis**