Beschreibung:
<jats:p>Osteophytic changes (OCs) have been identified on the cephalad articular processes (CAPs) of hypomobile zygapophysial (Z) joints of rats. Our objective was to refine the method of grading OCs for use in a large scale study. Thirty‐eight Z joint CAPs (left and right L4, L5, L6, and S1) of control and experimental rats were assessed. The experimental animals had undergone 8 weeks of fixation, using an established, IACUC approved, rat model, in which 3 contiguous segments (L4, L5, L6) were fixed with a specially engineered, surgically implanted, vertebral fixation device. The spines of all animals had been prepared for dissection microscopy. The CAPs were graded by 2 observers using specific OC criteria developed for this study. The lateral, cephalad, and dorsal surfaces of each CAP were systematically evaluated. Each observer graded the spines on 2 separate occasions, separated by 30 days. Intra‐ and inter‐observer reliability of grading was assessed using kappa coefficients. Results: Intra‐examiner reliability was 0.62. Inter‐examiner reliability was 0.64. We conclude that good reliability was achieved using these methods. Future studies will use a consensus procedure for segments scored differently by the two observers.</jats:p><jats:p>Support: NIH/NCCAM (Grant #s 1R21 AT00784 and U19 AT002006).</jats:p>