Posterior Lumbar Interbody Fusion Using Compressive Bone Graft with Allograft and Autograft in the Pyogenic Discitis

STUDY DESIGN: This is a retrospective study. PURPOSE: To evaluate the advantages and effects of posterior lumbar interbody fusion (PLIF) using allograft and posterior instrumentation in the lumbar pyogenic discitis, which are resistant to antibiotics. OVERVIEW OF LITERATURE: To present preliminary results of PLIF using a compressive bone graft with allograft and pedicle screw fixation in the lumbar pyogenic discitis. METHODS: Fifteen patients who had lumbar pyogenic discitis were treated by posterior approach from May 2004 to July 2008. The mean follow-up duration was 27.2 ± 18.68 months. The standing radiographs of the lumbar spine and clinical results were compared and analyzed in order to assess the bony union, the changes in the distance between the two vertebral bodies and the changes in the lordotic angle formed between the fused bodies immediately after surgery and at the final follow-up. RESULTS: Fifteen solid unions at an average of 15.2 ± 3.5 weeks after operation. The mean preoperative lordotic angle of the affected segments was 14.3 ± 15.1°, compared to 20.3 ± 12.3° after surgery and 19.8 ± 15.2° at last follow-up. For the functional result according to the Kirkaldy-Willis criteria, the outcome was excellent in 9, good in 5, fair in 1, and there were no poor cases. The average visual analogue scale score was decreased from 7.4 before surgery to 3.4 at 2 weeks postoperative. CONCLUSIONS: The main advantage in the procedure of PLIF using compressive bone graft with allograft and post instrumentation is early ambulation. We believe that this is another good procedure for patients with poor general condition because a further autograft bone harvest is not required.