Redo Surgery for Lumbar Postdiscectomy Discitis by Transforaminal Approach with or without Graft and Posterior Instrumentation
Authors: Rahimizadeh A. 
Published: June 2012

Introduction

Aggressive anterior debridement and fusion with autogenous bone graft followed with posterior instrumentation are the accepted mode for management of postoperative lumbar discitis failing to respond to conservative measures. This can be done in one stage same day or two stage operation. Here, we will describe our experience in single stage posterior transforaminal approach for debridement, interbody bone graft insertion, and posterior instrumentation with safe and less hospital stay and good long-term outcomes. This method has been described neither for pyogenic discitis nor for postdiscectomy discitis before.

Materials and Methods

The current study include 23 cases with postlumbar discectomy discitis not responding to antibiotic therapy and immobilization. The patients were divided into two groups. Group I includes nine patients with subacute discitis resistant to conservative measures. End plate destruction was minimal in the patients of this group. Therefore, only simple transforaminal debridement, irrigation with normal saline mixed with gentamycin and putting a small gentamycin pad in the space, was used in five patients with L4-L5, two with L3-L4, and two with L5-S1 postoperative discitis. Group II includes 12 chronic patients who had pain secondary to continuation of infection, despite of several weeks to months of antibiotic therapy or even one to two redo surgeries. Discitis in majority of these cases were accompanied with marked vertebral destruction resulting in deformity in three. In all of the patients of this group, transforaminal debridement and curettage was done. The pedicle screws were placed either in involved or in noninvolved vertebras before debridement and the space was distracted between the screws for ease of debridement. Subsequently, an appropriately shaped autogenous bone graft was inserted and fitted in the intervertebral disk space through transforaminal route. Later, the bony construct was secured by compression of the posteriorly placed hardware considering ideal lumbar lordosis, which was already brought by positioning of the operating table.

Results

In the first group, transforaminal debridement plus 2- to 3-week antibiotic therapy result in remarkable clinical paraclinical improvement. In both patients with L5-S1, discitis debridement results in massive venous bleeding at the final attempts of debridement necessitating package of the floor of the intervertebral disk space with Surgicel. Both of these subjects despite of ultimate disappearance of low back and radicular pain, showed occlusion of the left internal iliac vein necessitating anticoagulant treatment. Despite of anticoagulant therapy, both developed clinical manifestation of deep vein thrombosis with good recovery. In all patients of the second group, pain decreased dramatically within a few days after operation and laboratory markers lowered within a week or two and finally became normal within 6 weeks after surgery. All patients of the second group returned to their previous activities.

Conclusion

We believe that in the patients with postoperative spondylodiskitis, debridement through transforaminal approach is a simple and safe method in subacute cases. However, we strongly advise not to use this method in L5-S1 discitis. Reconstruction of the vertebral column with autogenous bone graft can be done through the same corridor in chronic subjects with vertebral destruction with or without deformity. Adding screw rod even in involved vertebras will secure the graft, but do not carry an additional risk. I confirm having declared any potential conflict of interest for all authors listed on this abstract Yes Disclosure of Interest None declared