The authors evaluated the extensor pollicis longus tendon in 62 patients with a distal radius fracture using high-resolution ultrasound 6 weeks after injury. All fractures were treated closed and the uninjured wrist was examined as a control. There was reduced peak velocity of tendon excursion and an increased thickness of both the extensor retinaculum and the tendon sheath on the fractured side. Fractures involving the joint surface were associated with a greater change in thickness of the tendon sheath. Only 1 extensor pollicis longus tendon ruptured: the rupture occurred 4 weeks after injury precluding ultrasound assessment.
Rupture of the extensor pollicis longus tendon occurs in up to 3% of fractures of the distal radius, and usually within 4 to 10 weeks of injury. Disruption is associated with undisplaced or minimally displaced fractures, but the exact mechanism of injury is unknown. The authors of this study postulated that the increased thickness of the extensor pollicis longus tendon sheath may impair an already tenuous blood supply and/or affect the diffusion of nutrients to the tendon within the third extensor compartment, leading to tendon attrition and rupture.
Radius, Fracture, Extensor, Pollicus, Longus
J of Hand Surgery