CT guidance assisted by electromagnetic navigation system for percutaneous fixation by internal cemented screws (FICS)

• Published in: European radiology 2020-02, Vol.30 (2), p.943-949
• Main Authors: Moulin, Benjamin, Tselikas, Lambros, De Baere, Thierry, Varin, Florent, Abed, Abdellahi, Debays, Laura, Bardoulat, Cécile, Hakime, Antoine, Teriitehau, Christophe, Deschamps, Fréderic, Gravel, Guillaume
• Format: Article
• Language: English
• Subjects: Accuracy; Adult; Aged; Aged, 80 and over; Bone Cements - therapeutic use; Bone imaging; Bone Screws; Cementing; Complications; Computed tomography; Deviation; Diagnostic Radiology; Electromagnetic Phenomena; Female; Femoral Neck Fractures - surgery; Femoral Neoplasms - secondary; Femoral Neoplasms - surgery; Femur; Fixation; Fluoroscopy - methods; Fracture Fixation, Internal - instrumentation; Fracture Fixation, Internal - methods; Fractures; Fractures, Spontaneous - surgery; Humans; Imaging; Internal Medicine; Interventional; Interventional Radiology; Male; Medicine; Medicine & Public Health; Middle Aged; Navigation systems; Neuroradiology; Palliation; Pelvis - surgery; Placement; Prevention; Radiation; Radiation dosage; Radiology; Retrospective Studies; Screws; Skin; Success; Surgery, Computer-Assisted - methods; Tomography, X-Ray Computed - methods; Ultrasound; Young Adult
• ISSN: 0938-7994; 1432-1084
• DOI: 10.1007/s00330-019-06408-0

Purpose To evaluate electromagnetic navigation system (ENS) for percutaneous fixation by internal cemented screw (FICS) under CT guidance. Background FICS is a recently developed modality that consists in inserting screws, under imaging guidance, into bone through a minimal skin incision. FICS recently showed good efficacy for the palliation or prevention of pathologic fractures of the pelvic ring and femoral neck. Materials and methods In this single-center retrospective study, we reviewed all consecutive cancer patients treated with percutaneous FICS under ENS-assisted CT guidance for the prevention or palliation of pelvic or femoral neck fractures. The primary endpoint was technical success. Secondary endpoints were screw placement accuracy (defined by proximal deviation p , distal deviation d , and angle deviation θ ), radiation dose exposure, number of CT acquisitions, duration of procedures, and complications. Results Mean duration of FICS procedures was 111 ± 51 min. Mean post-procedure hospitalization length was 2.1 days. Technical success was achieved in 48 cases (96%) with a total of 76 screws inserted. Mean distance p , mean distance d , and mean angle θ were respectively 8.0 ± 4.5 mm, 7.5 ± 4.4 mm, and 5.4 ± 2°. Angle θ accuracy was higher for screws with a craniocaudal angulation of less than 20° (4.4° vs 6.4°, p  = 0.02). The mean number of CT acquisitions during procedures was 6.4 ± 3.0. The mean dose length product was 1524 ± 953 mGy cm and the mean dose area product was 12 ± 8 Gy cm 2 . Five complications occurred in 4 patients. Conclusion CT guidance assisted by ENS is an effective approach for percutaneous FICS. Key Points • ENS-assisted CT enables screw insertion in the pelvic ring and femoral neck, with a wide range of trajectories, even when a significant craniocaudal angulation is required. • ENS-assisted CT can be used as an alternative to CBCT guidance for percutaneous fixation by internal cemented screw. • ENS-assisted CT provides high technical success rate with excellent placement accuracy.