[Septic arthritis of a lumbar facet joint. A case report].

Septic arthritis of the posterior lumbar joints is extremely rare in comparison with spondylodiscitis which is much more common. We report a case of an 86-year-old women with septic arthritis of the left L4-L5 lumbar facet joint associated with endocarditis. Arthritis diagnosis was made on CT scan and MRI, infection by Staphyloccocus aureus was proved by blood cultures.