Hematogenous pyogenic facet joint infection.

Study Design: Retrospective.
Objectives: To determine the incidence, clinical presentation, diagnostic laboratory values, imaging characteristics, and optimal treatment of hematogenous pyogenic facet joint infections.
Summary of Background Data: There are 27 documented cases of hematogenous pyogenic facet joint infections. Data regarding incidence, clinical presentation, diagnosis, and treatment response are incomplete because of the paucity of reported cases.
Methods: This is a retrospective study of all cases of hematogenous pyogenic facet joint infection treated at one institution. Data from previous publications were combined with the present series to identify pertinent clinical characteristics and response to treatment.
Results: A total of six cases (4%) of hematogenous pyogenic facet joint infection were identified of 140 cases of hematogenous pyogenic spinal infection at our institution. Combining all reported cases reveals the following: The average patient age is 55 years. Ninety-seven percent of cases occur in the lumbar spine. Epidural abscess formation complicates 25% of the cases of which 38% develop severe neurologic deficit. Erythrocyte sedimentation rate and C-reactive protein are elevated in all cases. Staphylococcus aureus is the most common infecting organism. Magnetic resonance imaging is accurate in identifying the septic joint and associated abscess formation. Percutaneous drainage of the involved joint has a higher rate of success (85%) than treatment with antibiotics alone (71%), but the difference is not significant (P = 0.37).
Conclusions: Hematogenous pyogenic facet joint infection is a rare but underdiagnosed clinical entity. Facet joint infections may be complicated by abscess formation in the epidural space or in the paraspinal muscles. Uncomplicated cases treated with percutaneous drainage and antibiotics may fare better than those treated with antibiotics alone. Cases complicated by an epidural abscess and severe neurologic deficit should undergo immediate decompressive laminectomy.