PMC5532760_01
(a) Visible swelling in the right distal volar forearm on clinical examination; (b) An axial section of an MRI scan clearly demonstrating a superficial muscle belly at the level of the distal radio-ulnar joint in keeping with a reversed palmaris longus (*); (c) A sizeable reversed palmaris longus muscle belly in right distal volar forearm.
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F0001
Clinical examination revealed a visible swelling in the right volar forearm (Figure 1(a)), which co-located with the site of the discomfort. An MRI scan of the forearm was initially reported as unremarkable, but request was made for review of the images, and a RPL was identified (Figure 1(b)). The operation was carried out uneventfully under general anaesthetic, and a sizeable palmaris longus muscle belly was identified and excised through a longitudinal incision (Figure 1(c)).
PMC5532760_02
A longitudinal section of an ultra-sound clearly demonstrating a reversed palmaris longus muscle belly (*) lying onto of the flexor retinaculum. The deep flexor tendons ( ) and radial carpal joint lie inferiorly.
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F0002
An USS-scan was requested, which demonstrated a reversed palmaris muscle at the site of the discomfort (Figure 2) and identified no other potential causes of the pain.