Please do not send aspirations from joint Haemarthroses for cytology or culture when the precipitating event was trauma. These investigations should be reserved for spontaneous effusions or conditions such as crystal or septic arthritis.
NB - full aseptic technique in all cases.
Shoulder
Elbow
Wrist
Knee
Ankle
Shoulder:
- Anterior – Just lateral to the coracoid, directing the needle posteriorly
- Posterior – Insert the needle 1 cm inferior and medial to the posterolateral corner of the acromium. Direct the needle anteriorly and medially towards the coracoid. The glenohumeral joint is about 3-4 cm deep to the skin
Elbow:
- Place the elbow at 90 degrees of flexion, pronated
- Locate the radial head, lateral epicondyle, and lateral aspect of the olecranon tip
- The centre of the aconeus triangle they form is the site of needle entry
- Aim the needle medially, perpendicular to the radius
Wrist:
- Enter between EPL and common extensor tendons, ulnar to the radial tubercle and ASB
Knee:
- Insert the needle 1cm inferior to the superior border of the patella, either lateral or medial
- Direct the needle slightly posteriorly and horizontally toward the joint (suprapatellar pouch) space
Ankle:
- Subtalar – Enter the joint just below the lateral malleolus
- Tibiotalar – Locate the sulcus between the medial malleolus and tibialis anterior / EHL tendons … with the foot in neutral. Next plantar flex the foot and enter the sulcus, aiming slightly cephalad
CUH arthrocentesis samples
- Direct microscopy - micro
- Crystal analysis - cytology
- C & S - micro
- Sample into blood culture media - micro
- Fluid in FBC bottle for WCC - Haematology