Optimal screw length in volar locking plate osteosynthesis for distal radius fractures: a systematic review

Fractures of the distal radius represent the most common fracture of the upper limb, and can be managed surgically with volar locking plate osteosynthesis (VLPO). Uncertainty remains regarding the optimal length of the distal locking screws. The aim of this study was to determine the optimal VLPO screw length which provided adequate stability while minimizing complications.

A systematic review of relevant literature published within Cochrane, PubMed, MEDLINE and Embase, including studies up to April 2020, was performed using the Preferred Reporting Items for Systemic Reviews and Meta-analysis (PRISMA) guidelines. Studies were included if they investigated distal radius fracture fixation with VLPO, screw lengths, complications, and associated imaging.

Search results identified 664 relevant studies, of which 14 studies examining 926 radii were included for review. Synthesis revealed that unicortical locking fixation with screws ~75% the depth of the radius, or 2 mm short of the dorsal cortex, provided equivalent stability to bicortical fixation. The lunate may be used as a proxy to determine radial depth at each quartile column. Inadvertent screw protrusion can be assessed by taking four images intra-operatively; anteroposterior (AP), lateral, 45° supinated and dorsal tangential views (DTVs). Radial shaft screws can have up to 2 mm prominence with no clinical significance.

Unicortical locking fixation at least 75% the depth of the distal radius provides equivalent stability to bicortical fixation in extra-articular fractures with lower complication rates. Imaging should be used to confirm that penetration of the dorsal cortex has not occurred.