Radio-capitellar joints

The lateral aspect of the elbow is best examined with both elbows in extension, thumbs up, palms of the hands together (Barr and Babcock 1991). When examining the radial collateral ligament and the capsule, the elbow should be extended, keeping the hand pronated. Along the lateral elbow, high-resolution US can demonstrate the common extensor tendon, the lateral ulnar collateral ligament, the radial nerve with its superficial and deep (posterior interosseous nerve) branches, and the radio-capitellar joint. 

The lateral aspect of the radio-capitellar joint can clearly be delineated with US (Fig. 8.18a). A triangular hyperechoic structure is usually seen filling the peripheral portion of the articular rim between the... 

The elbow is composed of three articulations-radio-capitellar, proximal radio-ulnar and trochlea-ulnasharing in a common joint cavity and stabilized by a number of soft-tissue structures, including the lateral and medial collateral ligaments and the anterior portion of the joint capsule. 

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