Minimising the risk of extensor pollicis longus rupture following volar plate fixation of distal radius fractures: a cadaveric study

Abstract

I read the above article with a great deal of interest. Tendon attrition resulting from iatrogenic damage with either drills or screws during distal radial fracture fixation is of course a concern. I commend the authors for producing an insightful paper in a clinically relevant area, given the recent expansion in the proportion of distal radial fractures being aggressively treated with osteosynthesis.1,2 However, a number of concerns still exist. Trying to predict which holes may present an increased risk of soft tissue damage is difficult and perhaps not as easily reproducible as suggested. This may be influenced by a number of factors including the precise implant position, screw width and screw length. Both the radial to ulnar and proximal to distal position of the plate may be altered depending on the fracture configuration, changing the position of the holes in relation to the extensor pollicis longus (EPL) tendon. In their cadaveric model, the authors used 1.6mm K-wires to assess EPL damage. The distal locking screws of the plates examined range from 2.3mm to 2.5mm. Would using the actual screws not have provided a more accurate picture of tendon injury? To avoid damage, the authors recommend leaving these centrally placed screw holes empty. This, however, may significantly compromise fracture stability, especially in die punch or coronal split fracture patterns. Judging when the drill has penetrated the far cortex can be problematic, particularly with dorsal comminution. Drilling carefully with a finger underneath the dorsal lip of the radius provides adequate proprioceptive feedback to allow the surgeon to gauge the position of the drill tip accurately, avoiding soft tissue damage. Fluoroscopic assessment of screw length, utilising views tangential to the radiocarpal surface in multiple planes, has been described to help with implant positioning and to avoid extensor compartment irritation.3,4 With a rapidly expanding market of volar plating systems, including new fragment-specific polyaxial locking plates, the authors remind us of the importance of respecting the soft tissue envelope when treating this common orthopaedic injury.