Clinical Results and Rationale for Lumbar Interbody Fusion with Threaded Titanium Cages

Abstract

The purpose of this study was to research the use of Titanium cage implantation as a spacer for re-expansion and maintenance of disc height in association with interbody fusion. Between June 1992 and May 1993, twenty patients (14 males and 6 females, mean age of 38.8 years with range 26 to 65) were implanted at 22 levels (9 at L4-5 and 13 at L5-S1). After removal of disc material and preparation of the intervertebral space by tapping the end plates, 2 cages were implanted per level and packed with autogenous bone. Follow-up spine X-rays were done at 6 weeks, and 3, 6, 12 and 24 months and yearly thereafter. Disc height was measured pre, intra and postoperatively. Ten levels demonstrated improvement of disc space from a mean of 6.8mm pre-operatively to 11.1mm postoperatively. Ten levels were maintained at 11.7mm. In 1 patient, both spaces collapsed postoperatively. At 3 to 5 years follow-up, the results on disc height were maintained and X-rays showed satisfactory fusion. There were no cases of infection, radicular deficit or CSF leak. The functional states improved on the Prolo scale. Posterior lumbar interbody fusion (PLIF) with Titanium cages was found to be a safe and efficacious technique. The rationale for maintaining or improving the disc space with cages is discussed.