A great case to highlight the advantages of ultrasound vs MRI with its dynamic assessment of structures. MCP joint radial collateral ligament rupture post trauma. On flexion the extensor apparatus of finger tightens over the ligament displacing it proximally and with extension it flicks back out...

The pulley apparatus functions to secure the flexor tendon onto the adjacent phalanx. During forceful gripping activities, significant forces are exerted on the pulley as it maintains the tendon's close proximity to the bone against the distracting force exerted by the tendon's line of pull. When...