Novel Tape Suture Osteosynthesis for Hyperextension Injuries of the Subaxial Cervical Spine: A Biomechanical Study

Abstract

Background/Aim: Anterior tension band injuries are usually the result of high impact hyperextension trauma. Current surgical treatment includes anterior cervical discectomy and fusion bearing the risk of soft tissue irritation, degeneration of adjacent cervical segments, implant failure or iatrogenic spondylodesis. This study examined the biomechanical properties of tape suture constructs reenforcing ligamental stability for the treatment of Association of Osteosynthesis (AO) type B3 injuries compared to anterior fusion. Materials and Methods: After creation of an AO type B3 injury in synthetic cervical segments (C5/6, Sawbone ® ), seven segments were treated with anterior fusion and seven with a tape suture construct, similar to the SpeedBridge™ (Arthrex ® ). Biomechanical testing was performed, simulating extension, flexion, lateral bending, and rotation. Dislocation (˚) and corresponding force (N) were measured and compared. Results: Anterior fusion displayed a mean range of extension, lateral bending, and rotation of 3.60˚(SD 1.87˚), 2.28˚(SD 1.55˚), and 2.81˚(SD 0.78˚), respectively. The tape suture showed a mean range of extension, lateral bending, and rotation of 4.24˚(SD 0.81˚) (p=0.146), 5.44˚(SD 1.56˚) (p=0.013), and 5.29˚(SD 1.44˚) (p<0.01), respectively. No specimen suffered from implant failure. Conclusion: The tape suture construct provides sufficient biomechanical stability for the treatment of AO type B3 injuries compared to anterior fusion. Regarding cervical extension, whose limitation is crucial for ligamental healing, the tape suture shows no significant inferiority. Yet, the tape suture approaches physiological mobility in the planes not affected by the injury. Consequently, the tape suture is a promising alternative preventing an iatrogenic spondylodesis.