Carbon-Fibre-Reinforced PEEK radiolucent intramedullary nail for humeral shaft fracture fixation: technical features and a pilot clinical study

This prospective pilot study investigated the safety and efficacy of a novel radiolucent intramedullary nail (IMN) made of Carbon-Fibre-Reinforced Polyaryl-Ether-Ether-Ketone (CFR-PEEK) for humeral shaft fracture fixation. A prospective, single-arm, four-centre study. A total of 46 patients with 46 humeral fractures classified as 12 A-B were treated with a novel CFR-PEEK IMN and followed for 12 months. Most of the patients (65%) were female; the mean age was 65 ± 17 years. The average operating time was 66.75 ± 19.84 minutes and X-ray exposure was 104.11 ± 98.01 seconds. All patients postoperatively reported selflimiting shoulder pain and three patients developed iatrogenic transient radial palsy. Two patients required repositioning of the implant. No implant-related complications were observed. Radiological consolidation was achieved in all 43 patients who completed the 12-month follow-up. The CFR-PEEK IMN is user-friendly and safe. Its bone-matching elastic modulus seems to contribute to its clinical efficacy. This, together with compatibility with modern imaging techniques, can be considered a further evolution of IMN designed to stabilise humeral shaft fractures.