F56 with fall onto hand and clinical features of UCL injury at MCPJ1.
Non-displaced tear of UCL at MCPJ1
The UCL at MCPJ1 is shown on long-axis ultrasound images at top and correlating PD-weighted coronal MR images (with & without fat suppression) at bottom. Both imaging methods demonstrate a swollen UCL with non-displaced tear at the distal insertion (solid arrows), appreciated on ultrasound as a hypoechoic line of interrupted fibre continuity and on fat-suppressed MRI as a markedly hyperintense line of ligament discontinuity (bottom right). Note normal location of overlying adductor aponeurosis (arrowheads), typical echopattern of UCL fibres which remain in situ (dashed arrows), and localised hyperaemia at the site of tear on Power Doppler ultrasound (image at top right). NOTE: UCL = ulnar collateral ligament