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Updated: Jul 10, 2026
Treatment with Locking Intramedullary Nailing for Intertrochanteric Fracture of the Femur Utilizing a New Awl with a Distal Positioner
Published on: June 6, 2025
Bone Union and Safety of the Long Chimaera Nail in Extracapsular Femoral Fractures: A Retrospective Multicenter Study
Armando Del Prete1, Giacomo Errico2, Giuseppe Iodice2
1Department of General Orthopedic, University of Florence, Azienda Ospedaliero-Universitaria Careggi, Florence, ITA.
Background:
Proximal femoral fractures (PFFs) are a major source of morbidity and mortality in the elderly. Although cephalomedullary nailing (CMN) systems are widely used for the treatment of extracapsular/trochanteric PFFs, the optimal implant choice remains debated - in particular, in the case of stable trochanteric fracture patterns. ChimaeraTM (Orthofix, Italy) is a novel CMN system designed to enhance fracture compression and rotational stability through a telescoping lag screw and optional anti-rotational element. This retrospective, multicenter, post-market study evaluated the clinical benefit and safety of the long ChimaeraTM nail in adults with extracapsular PFFs in a real-world setting.
Methods:
The study cohort included 44 patients (mean age: 74.0 ± 14.5 years; 68.2% female), whose clinical data were assessed to evaluate bone union within 12 months, as well as adverse events and complications.
Results:
Among patients included for union assessment evaluation (n=42), eventual union was clinically documented in all cases (100%; 95% CI: 91.6-100%); in line with the retrospective design and a variable imaging availability, this estimate refers to evaluable patients only, with X-ray documented union in 29 patients. Overall, 38.1% of evaluable patients had clinically documented union at first follow-up (1.3 months) and a median time to documented union of 7.4 months. Four adverse events (9.1%) and two reoperations (4.5%) were observed, none related to the device. No implant-related fractures or screw cutouts were reported, and no deaths were recorded. Mean operative time was 91.3 ± 45.7 minutes, and mean tip-apex distance (TAD) decreased from 27.2 mm postoperatively to 24.7 mm at late follow-up.
Conclusions:
Despite inherent limitations due to the retrospective design and the lack of a control group, results confirm the favorable benefit-risk profile of the ChimaeraTM long nail in a real-world setting, showing high consolidation rates and a low incidence of complications.
