Extradural infections of the spine

We have observed a recent increase in the incidence of spinal extradural infections. To determine postoperative outcome and prognosis we have undertaken a retrospective study on patients with spinal extradural abscesses between 1978 and 1996 treated in the Department of Neurosurgery at the Nordstadt Hospital in Hannover, Germany.

Case records, outpatient files, operation notes, neuroradiological examinations and pathological reports were analysed. Neurological function was documented using a score system for each symptom.

Twenty-two patients underwent 24 operations during the study period. Staphylococcus aureus was the organism most commonly isolated. Patients presented after a mean history of 1.8+/-2.6 months with acute development of severe para- or tetraparesis and were followed up for an average period of 6+/-7 months. Two groups were distinguished. One group was characterized by epidural collections of pus (14 patients). Two patients in this group were not operated due to their moribund state and died from uncontrollable septicemia. Two of the remaining 12 operated patients died within 30 days after surgery due to generalized septicemia or other medical problems unrelated to the spinal involvement. Of the ten surviving patients, five sustained major neurological deficits, whereas the remaining five patients made an incomplete recovery. The second group consisted of eight patients in a significantly better pre-operative health condition in whom granulomatous material was obtained during the operation and the outcome was considerably better. No patient in this group died. Six patients recovered with no or mild neurological deficits.

Spinal extradural infections require immediate surgical intervention. Neurological outcome depends on the pre-operative neurological status. Survival is determined by the general health condition of the patient.