Distal interlocking for short trochanteric nails: static, dynamic or no locking? Review of the literature and decision algorithm

Pertrochanteric hip fractures are among the most common and the use of short cephalomedullary nails as the treatment of choice is increasing. A systematic review regarding distal locking options for short cephalomedullary nails was undertaken using Medline/PubMed®, Embase® and Cochrane Library® in order to evaluate current indications, associated complications and to provide treatment recommendations. The results seem to support the use of distal static locking for unstable fractures, dynamic locking for length stable/rotational unstable fractures and no locking for stable fractures. Complications associated with distal locking include iatrogenic fractures, thigh pain, delayed union and nonunion, implant failure, screw loosening and breaking, drill bit breaking, soft tissue irritation, femoral artery branch injury, intramuscular haematoma and compartment syndrome. It is also associated with longer operative time and radiation exposure. In unlocked constructs, dorsomedial comminution and nail/medullary canal mismatch contribute to peri-implant fractures. Anterior cortical impingement is associated with cut-out and nonunion. Most studies comparing distally locked and unlocked nails report a short follow-up. Distal locking mode should be based on the fracture’s stability. Cite this article: EFORT Open Rev 2020;5:421-429. DOI: 10.1302/2058-5241.5.190045