Nail plate combination for Su type III periprosthetic distal femur fractures results in early ambulation and favorable clinical outcomes: A comparative case series and technical points.

Abstract

Periprosthetic distal femur fractures are deleterious injuries, found commonly in the elderly osteoporotic population, typically addressed with open reduction internal fixation (ORIF). Fractures that are very distal (Su type III) require special considerations due to limited distal bone stock for fixation. The utilization of the nail-plate combination (NPC) technique for these patients aims for an early return to ambulation by maximizing distal fixation and stability while allowing for immediate postoperative weight-bearing. The technical steps for NPC in very distal periprosthetic femur fractures are outlined in addition to a comparative case series of these injuries treated with NPC, retrograde intramedullary nail (rIMN), lateral locking plate (LLP), and dual plate contruct (DPC). Primary outcomes included postoperative weight-bearing status, ambulatory recovery using Koval scores, radiographic union (mRUST and documented union), reoperation, and mortality. All NPC patients were permitted immediate weight-bearing as tolerated (WBAT) on postoperative day 1, significantly more frequently than other constructs (p < 0.001), with maintained significance versus rIMN after correction (p = 0.012). There were no significant differences in Koval mobility scores at any postoperative time point. One-year mortality was 15.9%, and reoperation occurred in 20%, with no significant differences between constructs. Union outcomes were limited due to sparse data. Therefore, the NPC is a useful method that allows immediate and consistent functional recovery and stability for very distal periprosthetic femur fractures.