Background: Intramedullary hip nails may be classified as blades or screws depending on the type of lag screw used. Recently, a combination of lag screw types with a U-clip insertion has also been used. The purpose of this study was to evaluate the clinical and radiological outcomes of these new screw types.Methods: A total of 185 patients with trochanteric femoral fractures (age ≥ 65 years) who underwent surgery with intramedullary nails were selected. Surgeries with InterTrochanteric/SubTrochanteric (ITST), Proximal Femoral Nail Antirotation (PFNA), and Gamma 3 U-Blade lag screws were performed between January 2011 and June 2016. The AO/OTA classification, presence of a basicervical fracture type on 3D-CT, BMI, BMD, reduction quality, position of the lag screw, TAD (tip apex distance) of the lag screw, sliding distance of the lag screw, varus change (neck shaft angle), radiological union period, fixation failure and functional outcome as determined by walking ability were analyzed.Results: There were 3/60 (5.0%) cases of fixation failure in the ITST group, all caused by cut-out; 4/57 (7.0%) in the PFNA II group: 3 caused by cut-through and 1 by metal fracture; 1/68 (1.5%) in the Gamma 3 U-Blade lag screw group (P= 0.301). In each group, the sliding distance of the lag screw showed a significant difference (P= 0.017), whereas significant sliding over 10 mm showed no statistically significant results.Conclusion: There was only one (1.5%) case of fixation failure in the Gamma 3 U-Blade lag screw group. The sliding distance of the U-Blade was found to be in the middle, between the PFNA II (shorter) and ITST (longer) implants. The new rotational control lag screw seems to be comparable to other screw types.

Background: Locking a compression plate is a more favorable surgical technique than intramedullary nailing in the treatment of distal femur fractures. This study analyzed the risk factors of proximal screw breakage retrospectively, which was confirmed in the patients with plate removal after bony union. Methods: A total of 140 patients who were fixed by MIPO using ZPLP from 2009 to 2019 were identified. A total of 42 patients met the inclusion criteria and were included. The screw breakage group (12 patients) and the non-breakage group (30 patients) were compared. Results: Approximately 12 (28.6%) of 42 plate-removal patients showed proximal screw breakage. The breakage of proximal screws developed at the junction of the screw head and neck. The number of broken proximal screws averaged 1.4 (1~4). The breakage of the proximal screw even after the bony union is more frequent in older patients (p = 0.023), the dominant side (p = 0.025), the use of the cortical screw as the proximal uppermost screw (p = 0.039), and the higher plate-screw density (p = 0.048). Conclusions: Advanced age, dominant side, use of the cortical screw as the uppermost screw, and higher plate-screw density were related to proximal screw breakage. When the plate is removed after bony union or delayed union is shown in these situations, the possibility of proximal screw breakage should be kept in mind.

Kwak YH, et al. J Korean Knee Soc. 2011 Jun;23(2):128-132. http://dx.doi.org/10.5792/jkks.2011.23.2.128