Anterior interbody fusion of the cervical spine with

Anterior interbody fusion of the cervical spine with Zero-P spacer (Prospective study – radiological results with one year follow up minimally ) Vanek P, Saur K, Bradac O PURPOSE OF THE STUDY The aim of this study was to compare efficacy of anterior cervical microdiscectomy and fusion in cases of symptomatic cervical spine spodylosis with new anchored spacer and with standard cage plate construct in regards to radiologic results and fusion rates. Department of Neurosurgery, Charles University and Central Military Hospital Prague, Czech Republic MATERIAL A total number of 113 consecutive patients were enrolled in this prospective study between October 2008 to July 2009. Mono- or bisegmental spondylosis were responsible for patients symptomatology. Conservative treatment of cervicobrachial symptomatlogy was with no effect in all cases and patients suffered by myelopathy weren´t enrolled. METHODS All patients underwent standard anterior microdiscectomy (in one or two levels), new designed anchored spacer Zero-P (Pic. 1) was used in 61 patients (group 1) and in 52 cases was stabilization done using interbody spacer Cornerstone and dynamic plate Premier (Pic. 2) (group 2). Lateral radiographic views of the cervical spine were obtained before surgery and 6 weeks, 3, 6 and 12 months after surgery. Sagital alignment of the cervical spine (Cobb. C), segmental angle of treated levels (Cobb. S), amount of segmental collaps and fusion rate were measured during follow up. Pic. 1 Fusion with Zero-P cage Pic. 2 Fusion with spacer Cornerstone and dynamic plate Premier RESULTS There was no significant difference in Cobb. C during follow up (0, 051) between both groups. Significant difference for first two values of Cobb. S was found (p < 0. 001), but the next course of Cobb. S changes was without any difference in both groups. (Fig. 1) The mean interspace collapse was without significant difference in both groups. (Fig. 2) The fusion rate was significantly higher in group 1 nine months after surgery (p = 0, 032), but was the same 12 months after surgery (p = 1, 0) CONCLUSIONS The anchored spacer Zero-P provide a similar biomechanical stability compare to stability of cage and dynamic plate construct. The ambition to improve „stand alone“ concept and eliminace disadvantages of plate systems has to be proven on larger group of patients and during longer follow up. Nothing to disclose Fig. 1 The course of Cobb. S values in the follow up Fig. 2 The course of relative segmental height in the follow up