Inflammatory mediators in posttraumatic radiocarpal osteoarthritis

Purpose: To identify the mediator profile in healthy, pre-osteoarthritis (OA) and end-stage OA radiocarpal joints. We hypothesized that there would be an increase in soluble mediators in posttraumatic wrist OA.

Methods: We obtained radiocarpal synovial fluid samples from 3 groups of patients: healthy control (n = 12) samples were collected during wrist ganglion resection; pre-osteoarthritic (n = 16) samples, during a 3-ligament tenodesis procedure for complete scapholunate dissociation; and end-stage OA (n = 20) samples in patients with proven radiological OA changes. Using a multiplex enzyme-linked immunosorbent assay, we measured 12 mediators: interleukin (IL)-1β, tumor necrosis factor-α, oncostatin-M, interferon-γ, IL-4, IL-6, IL-7, IL-8, IL-10, IL-13, IL-1RA, and osteoprotegerin. Statistical analysis was performed using analysis of variance and Bonferroni-corrected post hoc tests.

Results: Mediators IL-6, IL-10, and interferon-γ were increased in OA wrists compared to healthy and pre-OA samples. Tumor necrosis factor-α, oncostatin-M, osteoprotegerin, IL-8, and IL-1RA were detected but not at increased levels in OA wrists. We found no differences between healthy and pre-OA joints in all 12 mediators. Mediators IL-4, IL-7, IL-13, and IL-1β were not detected in either healthy, pre-OA or end-stage OA samples.

Conclusions: We identified no differences between healthy and pre-OA samples, suggesting no alteration in inflammatory status at the time of the 3-ligament tenodesis procedure. Consequently, mechanical disturbance seems to be the driving force toward OA and OA-associated inflammation in this stage of scapholunate dissociation. Increased levels of interferon-γ, IL-6, and IL-10 confirm inflammatory changes in the mechanically disturbed posttraumatic radiocarpal joint.