Three-level anterior cervical decompression and fusion using the Zero-profile implant system

Owing to the complications and limitations associated with anterior plating, a new zero-profile, standalone device (Zero-P, Synthes GmbH, Switzerland) for ACDF has been designed in an attempt to overcome the adverse effects associated with traditional cervical anterior plating. Even the excellent outcomes showed in single or two-level ACDF, however, the safety and efficacy of the Zero-P implant applied in three-level ACDF has been little explored. Results from previous biomechanical studies showed that segmental stability decreases with the number of instrumented segments regardless of the used implant but the locking plate and cage construct was stiffer in all test modes than the Zero-P devices in multilevel constructs. However, whether this difference will affect the clinical outcomes still remains unclear. By presenting the clinical and radiographic outcomes of six cases with a short follow-up of 24 months, we are hoping to clarify the safety and effectiveness of three-level ACDF with the zero-profile implant system. The overall results of our study were good. Postoperative complications such as hoarseness, dysphagia, cerebrospinal fluid leakage, malposition of the prosthesis and screw loosening or pull-out were not observed. The patients’ clinical symptoms were relieved 6 months after surgery. All the patients reached bony fusion at the sixth month follow-up according to the standard definition. The preliminary clinical and radiographic outcomes from this case series study demonstrated that the Zero-P implant system may be a safe and efficacious device in ACDF surgery. However, as this is just a case series study, larger randomized controlled studies of longer duration are warranted.