A novel internal fixation method for open book injuries of the pubic symphysis— A biomechanical analysis. (July 2020)

• Record Type: Journal Article
• Authors: Fritz, Tobias; Mettelsiefen, Laura; Strobel, Friedemann; Braun, Benedikt J.; Herath, Steven C.; Hopp, Sascha J.; Histing, Tina; Pohlemann, Tim; Pizanis, Antonius
• Is Part Of: Clinical biomechanics. Volume 77(2020)
• Publication Date: 2020-07
• Subjects: Internal fixator -- Symphysis -- Open Book injury -- Compression forces symphysis; AO Arbeitsgemeinschaft Osteosynthese -- DCP dynamic compression plate -- e.g. exempli gratia -- HOMFOR Homburg Funding (Funding by Saarland University) -- kHz kilohertz -- mm millimeter -- N Newton -- Nm Newton.meter -- SLDCP symphyseal locking dynamic compression plate -- 3D three-dimensional; Biomechanics -- Periodicals; Osteopathic medicine -- Periodicals; Biomechanics -- Periodicals; Osteopathic Medicine -- Periodicals; 612.76
• DOI: 10.1016/j.clinbiomech.2020.105009
• Languages: English
• ISSNs: 0268-0033

Abstract

Abstract: Background: Pelvic fractures in adults are common injuries and account for up to 3.64% of all fractures. Usually, the treatment of open book injuries (Types B1.1 and B1.2 AO-Classification) is open reduction and plate stabilization using dynamic compression plates, with or without interlocking screws. These implants seem to enhance the outcome of such injuries, but also variety of complications occurs. To reduce complications and achieve appropriate reduction and stabilization, this study compared established stabilization techniques to a novel minimally invasive internal fixation method using an internal fixator system that is already being utilized for spinal fractures. Methods: This study was performed on 32 composite pelvises in a bilateral stance biomechanical model. The pelvises were variously stabilized with an internal fixator, a 4.5 mm dynamic compression plate and a 3.5 mm symphyseal locking dynamic compression plate. The contact area and loading forces were assessed by a sensor film inside the symphyseal gap. Findings: This study showed significantly greater reduction and loading capabilities of the internal fixator compared to the other implants (p < 0.05). There was also significantly greater contact area with the use of an internal fixator compared to the other implants (p < 0.05). The 3.5 mm interlocking plate showed significantly greater contact area compared to the 4.5 mm plate (p < 0.05). Interpretation: The internal fixator that is already proven in spinal surgery is biomechanically superior to conventional implants used in pelvic surgery. The contact area analysis furthermore showed a more physiological loading pattern, which can improve ligamentous healing in a clinical context. Highlights: Better contact area with internal fixator; contact maintained during loading Higher distribution of contact area across pubic symphysis with internal fixator Significantly higher compression forces achieved with internal fixator