Page 8 - MSK assignment

8 F. Elahi

assessing the olecranon for joint effusion, it is effective to have the patient bend their arm.
Recall, a small amount of fluid between the humerus and fat pad is physiological. The
sonographer will note the elevated anterior and posterior fat pads, which will begin to appear
similar to a crescent moon (​De Maeseneer et al., 1998)​. The fluid seen in the joint space
appears anechoic as demonstrated in Figure F. The sonographer should rule out any synovial
thickening or loose bodies that may be present (Villegas et al., 2012).

Synovial hypertrophy
The synovium is found on joint surfaces, bursae, and tendon sheaths. It is a thin
membrane that lines certain areas to provide nutrition and lubrication to the joint cartilage.
Synovial hypertrophy is the thickening of the synovium. This thickening can be caused by
inflammation, infection, degeneration, trauma, hemorrhage, or neoplasm. Synovial hypertrophy
is often seen in patients with synovitis, rheumatoid arthritis, or pigmented villonodular synovitis
(Turan et al., 2017). The sonographic appearance of synovial hypertrophy is an enlarged
synovium. The synovium is normally 20-40mm when measured in a cross-section. The
sonographer may even compare to the contralateral side (Smith, 2011). In Figure G, the
thickened synovium is evident. The fat pad moves as the synovium enlarges and fluid builds up,
giving a sail-like appearance (Bianchi & Martinoli, 2007).

Cubital Tunnel Syndrome

The ulnar nerve is compressed within the cubital tunnel, this may happen at the edge of the
arcuate ligament or the condylar groove. The etiology of this syndrome includes shallow
condylar groove, abnormalities in the bone, and the presence of soft-tissue lesions. Patients
present with symptoms including medial elbow pain and sensory symptoms. The sensory
symptoms are often noted in the ring and pinky fingers, due to the association of these fingers
with the ulnar nerve. Patients with cubital tunnel syndrome are also known to
present with a claw-like hand (Figure H), due to the semi-flexion of the ring
and pinky finger. The pinky finger is also known to abduct from the hand,
known as Wartenberg sign. The degradation of the hand muscles is seen at
the first interosseous space and hypothenar eminence which causes the
flexion (Bianchi & Martinoli, 2007).