Factors Predictive of Blocking Screw Placement in Retrograde Nailing of Distal Femur Fractures

Objectives: (1) Identify factors that predict blocking screw placement in the treatment of a distal femur fracture with retrograde nail fixation and (2) determine whether acceptable alignment and stability were achieved in fractures that received blocking screws. Design: Retrospective Comparative Study. Setting: Level I Trauma Center. Patients/Participants: Between 2011 and 2017, we identified 84 patients with distal third femur fractures treated with a retrograde femoral nail. Data were analyzed according to those who did (BLOCK, n = 30) and did not (NO BLOCK, n = 54) receive blocking screws. Patients in both groups were treated by orthopaedic trauma surgeons; postoperative weight-bearing radiographs were obtained of every patient. Intervention: Fixation using a retrograde femoral nail with or without blocking screws. Blocking screws were placed at the discretion of the treating surgeon to reduce malaligned fractures or improve stability. Main Outcome Measurements: (1) Demographics, radiographic apparent bone gap (RABG), space available for the nail (SAFN), and distal segment length [as a ratio of bicondylar width (BCW)]; and (2) post-operative alignment and stability (change in alignment over time). Results: Patients treated with blocking screws had a higher body mass index (BMI) (BLOCK: 29.0, NO BLOCK 25.7, P = 0.03). In addition, the BLOCK group had larger RABGs (BLOCK: 8.2 mm, NO BLOCK: 3.6 mm, P = 0.02), more SAFN (BLOCK: 51.4 mm, NO BLOCK: 39.8 mm, ...
Source: Journal of Orthopaedic Trauma - Category: Orthopaedics Tags: Original Article Source Type: research