Towards the optimum spinal fusion device

Abstract

Spinal interbody fusion (spondylodesis) remains a gold standard for the treatment of instability, deformity and degenerative disease of the spine. Over the past 40 years surgical techniques and implant-device (cage) technology for spinal fusion have changed significantly. Design and materials have evolved with one common goal, to develop suitable implants that would address all three major issues of the procedure: stability, restoration of lordosis and osteointegration. Historically, two main materials have been utilized in the creation of cages: titanium (Ti) and polyetheretherketone (PEEK). The focus of spinal surgeons is constantly shifting from one material to another, because of the aggressive, commercial drive from the industry. The choice of optimal spinal interbody fusion device was always a matter of controversy. Therefore, this article aims to provide an overview of the different materials and designs from the biomechanical and also clinical aspect. A systematic review of the literature was made. The inadequate available clinical trials and lack of comparisons between different models have prevented definitive conclusions; therefore, further prospective randomized studies are necessary in the future to define one cage as a mainstay of clinical practice. Keywords: spondylodesis, cage, titanium, polyetheretherketone Zatrditev hrbteni~nega segmenta (spondilodeza) predstavlja zlati standard zdravljenja nestabilnosti, deformacij in degenerativnih bolezni hrbtenice. V zadnjih 40 letih so se kirur{ka tehnika in umetni medvreten~ni vsadki (kletke) ob~utno spremenili. Oblika in materiali so se razvijali z enim skupnim ciljem, to je odkriti vsadek, ki bi omogo~al stabilnost hrbteni~nega segmenta, vzdr`evanje lordoze ter osteointegracijo. Zgodovinsko gledano sta bila dva najpogosteje uporabljena materiala titan in polietereterketon. Dandanes med hrbteni~nimi kirurgi ostaja nesoglasje glede optimalne izbire umetnega medvreten~nega vsadka. Namen tega~lanka je predstaviti prednosti in slabosti najpogosteje uporabljenih materialov. Na podlagi aktualne strokovne literature je bila opravljena primerjava biomehanskih in klini~nih rezultatov razli~nih vsadkov. Glede na pomanjkljivost naklju~nih prospektivnih multicentri~nih {tudij ostaja izbira optimalnega umetnega hrbteni~nega vsadka {e naprej problemati~na.