5.1.1 Cause

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  Osteoarthritis.

  
  
• 
  

  Occasionally acute or chronic overuse.

5.1.2 Presentation

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  Pain is located within the elbow joint with referral into the muscles of the forearm.

  
  
• 
  

  Depending on the severity of the underlying pathology, a varying degree of capsular restriction may present. The capsular pattern of the elbow is more limited flexion, less limited extension.

5.1.3 Equipment

See Table  5‑1.

5.1.4 Anatomical Considerations

The elbow joint consists of three separate articulations. The radiohumeral, radioulnar, and humeroulnar joints. The safest and easiest method is to use a posterolateral approach placing the needle between the head of the radius and the capitellum. Using this approach the clinician need to be troubled about no anatomical structures.

5.1.5 Procedure

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  The patient is seated with the arm resting on a table in front of him or her and with the elbow in slight flexion.

  
  
• 
  

  The transducer is placed in the longitudinal plane over the posterior aspect of the radiohumeral joint so that both the radial head and capitellum may be clearly visualized.

  
  
• 
  

  Identify the gap between the radial head and capitellum with your finger.

  
  
• 
  

  The needle is then inserted at approximately 45 degrees to the transducer in a distal to proximal direction so that the tip enters this gap between the superior surface of the radial head and capitellum.

  
  
• 
  

  The injection is given as a bolus and should flow freely.

5.1.6 The Injection

See Fig.  5‑1 and Fig.  5‑2.

5.1.7 Notes

Osteoarthritis of the elbow is relatively rare unless there has been a significant preceding injury. This said in patients who do have symptomatic osteoarthritis, judicious use of corticosteroid or hyaluronan injection can provide significant relief of pain and improved function.

If a patient complains of locking or “catching”-like symptoms, injection should be avoided until further imaging is arranged to assess for the possibility of loose bodies. If present, a surgical opinion should be sought with a view to removal in order to avoid further possible joint damage.

5.2.1 Cause

• 
  

  Acute or chronic overuse.

5.2.2 Presentation

• 
  

  Pain is located over the lateral aspect of the elbow joint with occasional referral into the muscles of the forearm.

  
  
• 
  

  A good range of elbow movements is usually maintained with pain being elicited with resisted wrist extension and on direct palpation of the lateral elbow.

5.2.3 Equipment

See Table  5‑2.

5.2.4 Anatomical Considerations

Tennis elbow most commonly affects the common extensor tendon at its origin on the anterior facet of the lateral epicondyle of the humerus. The anterior facet faces anterolaterally.

Although the anterior facet of the epicondyle is the most common site, pain can also originate from the junction between the common extensor tendon and the extensor muscles more distally or at the origin of extensor carpi radialis longus more proximally on the lower third of the epicondylar ridge.

5.2.5 Procedure

• 
  

  The patient is seated with the arm resting on a table in front of him or her and with the elbow at approximately 90 degrees of flexion.

  
  
• 
  

  The transducer is placed in the longitudinal plane over the common extensor tendon at its origin on the lateral epicondyle.

  
  
• 
  

  The needle is inserted at approximately 45 degrees to the transducer in a distal to proximal direction so that the tip enters the common extensor tendon passing through the tendon to be positioned resting against the anterolateral facet of the epicondyle deep to the tendon.

  
  
• 
  

  Positioning the needle too vertically will risk the needle tip being placed within the substance of the radial collateral ligament or within the elbow joint itself.

  
  
• 
  

  The bulk of the injection is delivered deep to the common extensor tendon followed by fenestration of the tendon itself.