A Case Report of Extensor Pollicis Longus Tendon Rupture: Delayed Diagnosis in a Professional Rugby Player.

Spontaneous rupture of the extensor pollicis longus (EPL) tendon has been reported to be uncommon. Several possible causes and precipitating factors have been reported for this rupture, including prior surgery to the distal radius. We report the case of an 18-year-old male professional athlete who presented with an inability to extend their left thumb. They presented with this condition after open reduction and internal fixation (ORIF) for a fractured left distal radius. Findings were consistent with the rupture of the EPL tendon. The typical presentation of such a rupture is one to four months after ORIF surgery, a shorter delay than seen in the present case, which exceeds one year. They underwent surgical tendon transfer using the extensor indicis tendon, and a dorsally protruding surgical screw was removed from the volar aspect of the radius. In this case, we suggest that repetitive friction from the protruding surgical screw, following volar plating of a distal radius fracture, may have caused abrasion of the EPL tendon. This may have predisposed it to rupture. This can occur long after the placement of a volar plate and must be considered as a potential cause of an EPL tendon rupture.