Postoperative spondylodiskitis: Etiology, clinical findings, prognosis, and comparison with nonoperative pyogenic spondylodiskitis

We studied 31 cases of postoperative pyogenic spondylodiskitis (POS), compa ring them with 72 cases of nonpostoperative pyogenic spondylodiskitis (NPOS ). POS represents 30.1% of cases of pyogenic spondylodiskitis. The onset of symptoms occurred an average (+/-SD) of 27.7 (+/- 25.3) days following sur gery. Predisposing factors were less frequent in POS than NPOS cases (P =.0 02). Neurological complications and inflammatory signs in the spine were mo re frequent with POS than with NPOS (P =.002 and P < .00001). Coagulase-neg ative Staphylococcus and anaerobic bacteria were more frequent in POS than in NPOS (P = .0001 and P = .05). Percutaneous bone biopsies yielded the eti ology in 66.7% of cases, open bone biopsies in 100%, blood cultures in 55.6 %, and cultures of adjacent foci in 94.4%. Eleven patients (35.5%) were cur ed with antimicrobial treatment, but surgical treatment was necessary in 64 .5%. No relapses or deaths were recorded. Seventeen patients (54.8%) had se vere functional sequelae, which were associated with inflammatory signs in the spine (P = .033), higher levels of leukocytosis (P = .05), higher eryth rocyte sedimentation rates (P = .05), and paravertebral abscesses (P = .04) .