Application of titanium and polyetheretherketone cages in the treatment of pyogenic spondylodiscitis.

OBJECTIVE: Surgical treatment of a pyogenic spondylodiscitis (PSD) involves a fixation and debridement of the affected segment combined with a specific antibiotic therapy. To achieve a proper stability and to avoid pseudarthrosis and kyphotic malposition many surgeons favour the interposition of an anterior graft. Besides autologous bone grafts titanium (TTN) cages have gained acceptance in the treatment of PSD. Polyetheretherketone (PEEK) cages have a more favourable modulus of elasticity than TTN. We compared both cage types. Primary endpoints were the rate of reinfection and radiological results.

METHODS: From 2004 to 2013 51 patients underwent surgery for PSD with fixation and TTN or PEEK cage-implantation. While lumbar patients underwent a partial discectomy by the posterior approach, discs of the cervical and thoracic patients had been totally removed from anterior. Clinical and radiological parameters were assessed in 37 eligible patients after a mean of 20.4 months. 21 patients received a PEEK- and 16 patients a TTN-cage.

RESULTS: A reinfection after surgery and 3 months of antibiotic therapy was not observed. Solid arthrodesis was found in 90.5% of the PEEK-group and 100% of the TTN-group. A segmental correction could be achieved in both groups. Nonetheless, a cage subsidence was observed in 70.3% of all cases. Comparison of radiological results revealed no differences between both groups.

CONCLUSIONS: A debridement and fixation with anterior column support in combination with an antibiotic therapy appear to be the key points for successful treatment of PSD. The application of TTN- or PEEK-cages does not appear to influence the radiological outcome or risk of reinfection, neither does the extent of disc removal in this clinical subset.