Articular cartilage degeneration is mediated by inflammatory cytokines and fragments of structural matrix proteins. Few studies have examined the role of these biomarkers in intra-articular pathology of the ankle.
Four groups of patients with increasing ankle pathology were enrolled. Group 1 included controls with no pain who underwent unrelated forefoot surgery. Group 2 included patients undergoing arthroscopy with intraoperative mild chondrosis. Group 3 included patients undergoing arthroscopy with moderate/severe chondrosis, osteochondral lesions, impingement, or loose bodies. Group 4 included positive controls with severe arthrosis undergoing ankle arthrodesis/arthroplasty. Ankle fluid was obtained by intra-articular aspiration and was assayed for IL-6, IFN-γ, MCP, MIP-1β, and fibronectin-aggrecan complex (FAC), a matrix-degradation marker. There were 36 patients total, 21 males and 15 females with a mean age 45 (±16; range 18 to 76) years and a mean VAS for pain of 4.7 (±3.5; range 0 to 9). In groups 1 through 4, there were 11, 6, 15 and 4 patients respectively.
The mean values of MCP-1 were 49.8 (±8.0) for minimal pathology and 133.9 (±33.0) for substantial pathology (pg/ml). The mean values of the FAC were 2.83 (±1.16) for minimal pathology and 9.62 (±2.23) for substantial pathology (optical density at 450 nm). The groups differed significantly in age, preoperative VAS, FAC, IL-6, and MCP-1 (p<0.05).
These tests may play a role in determining the necessity for arthroscopy or intra-articular procedures in equivocal candidates.
There are differences in FAC and MCP-1 with increasing grades of severity of intra-articular pathology.