title: Lumbar facet joint arthritis is associated with more coronal orientation of the facet joints at the upper lumbar spine.
abstract: We retrospectively analyzed CT scans of 620 individuals, who presented to our traumatology department between 2008 and 2010. Facet joint (FJ) arthritis was present in 308 (49.7%) individuals with a mean grade of 1. It was seen in 27% of individuals ≤40 years and in 75% of individuals ≥41 years (P < 0.0001) as well as in 52% of females and 49% of males (P = 0.61). Mean FJ orientation was 30.4° at L2/3, 38.7° at L3/4, 47° at L4/5, and 47.3° at L5/S1. FJ arthritis was significantly associated with more coronal (increased degree) FJ orientation at L2/3 (P = 0.03) with a cutoff point at ≥32°. FJs were more coronally oriented (48.8°) in individuals ≤40 years and more sagittally oriented (45.6°) in individuals ≥41 years at L5/S1 (P = 0.01). Mean FJ asymmetry was 4.89° at L2/3, 6.01° at L3/4, 6.67° at L4/5, and 7.27° at L5/S1, without a significant difference for FJ arthritis. FJ arthritis is common, increases with age, and affects both genders equally. More coronally oriented FJs (≥32°) in the upper lumbar spine may be an individual risk factor for development of FJ arthritis.
authors.affiliation: Division of Trauma Surgery, Department of Surgery, University Hospital Zürich, Rämistrasse 100, 8091 Zürich, Switzerland.
authors.forename: Thorsten
authors.initials: T
authors.lastname: Jentzsch
authors.forename: James
authors.initials: J
authors.lastname: Geiger
authors.forename: Stefan M
authors.initials: SM
authors.lastname: Zimmermann
authors.forename: Ksenija
authors.initials: K
authors.lastname: Slankamenac
authors.forename: Thi Dan Linh
authors.initials: TD
authors.lastname: Nguyen-Kim
authors.forename: Clément M L
authors.initials: CM
authors.lastname: Werner