Ultrasound: Joint

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Background

  • U/S can demonstrate joint effusions and aid in diagnostic procedures such as joint aspiration and hematoma blocks
  • Common joints that are amenable to ultrasound includes glenohumoral, elbow, wrist, hip, knee, and ankle joint
  • Shoulder dislocations can be found with SN and SP nearing 100% in both diagnosis and assessing reduction[1]

Joint Effusion

Images

Normal

Abnormal

Joint effusion

Instructions

  1. Select linear probe (high frequency probe) for smaller joints such as elbow, wrist, ankle, or knee
  2. Select curvelinear probe (low frequency probe) for larger joints such as shoulder or hip joint
  3. Scan joint longitudinally to identify the joint space and adjacent bones
  4. Rotate 90° over area of concern

Findings

  • Positive
    • Substantial quantity of anechoic fluid (in comparison to contralateral side)
  • Negative
    • Trace or no effusion

Pearls and Pitfalls

  • Compare contralateral joint

Shoulder Dislocation

Images

Normal

Reduced shoulder

Abnormal

Dislocation

Reduction

In-Vivo Shoulder Reduction[2]

Instructions

Posterior Approach

  1. Select curvilinear probe (low frequency probe)
  2. Place probe to the posterior chest parallel above the scapular spine
  3. Identify the glenoid and humeral head

Anterior Approach

  1. Select curvilinear probe (low frequency probe)
  2. Place probe to the anterior chest parallel to the glenohumeral joint
  3. Identify the glenoid and humeral head

Findings

  • In anterior and posterior shoulder dislocations, the humeral head is displaced anterior or posterior to the glenoid fossa, respectively
  • Hematoma may be present and appear hyperechoic next to the glenoid fossa

Pearls and Pitfalls

  • Always compare findings with the unaffected joint

See Also

External Links

References

  1. Abbasi, S, et al. Diagnostic Accuracy of Ultrasonographic Examination in the Management of Shoulder Dislocation in the Emergency Department. Annals of Emergency Medicine. 2013; 62(2):170–175.
  2. http://www.thepocusatlas.com/musculoskeletal/