Abstract

Postoperative disk space infection or diskitis (POD) is a relatively uncommon but debilitating complication of disk sur-gery [1, 2], and despite the current level of knowledge, its reasonably early clinical diagnosis is still difficult to make [3, 4]. Once POD is clinically suspected and the erythrocyte sedimentation rate is shown to be elevated, radiologic studies may not demonstrate the early changes or at least may not differentiate it from postoperative changes [1]. Although per-cutaneous fine needle aspiration biopsy sampling of the sus-pected disk space in POD has some strong advocates, the small samples obtained have raised doubts as to the accuracy of negative bacteriologic results [5]. We have recently used a new automated percutaneous biopsy technique that allowed large specimens to be obtained successfully with minimal risk of morbidity. Materials and Methods Once POD is clinically suspected, an automated percutaneous biopsy may be conducted immediately in accordance with the follow-ing procedure. In the lateral decubitis position, under local anesthesia with fluoroscopic guidance, an 18-gauge hubless trocar is placed down to the disk space at an angle of approximately 30- 45 °. The entry point is approximately 8-12 em lateral to the posterior middle line. The position of the trocar is confirmed by anteroposterior and lateral views on fluoroscopy. The trocar is then advanced into the center of the disk, and then over this is placed a 2.8-mm cannula, which is advanced against the disk margin. The cannula is confirmed to be against the anulus on the oblique view. Then the trephine is introduced over the trocar through the cannula and the anulus is incised.