Altered post-dance serum cartilage oligomeric matrix protein response in dancers with chronic ankle instability: A pilot study.

Dancers with chronic ankle instability (CAI) may experience altered joint loading that elevates cartilage metabolic stress. Serum cartilage oligomeric matrix protein (sCOMP) is a sensitive biomarker of mechanical cartilage loading, yet its acute response to dance-specific activity in this population remains unknown. This pilot study examined acute changes in sCOMP following a standardized dance session and their associations with CAI severity, balance, and functional performance. Thirty female modern dancers (CAI group, n = 15; healthy control group, n = 15) completed a single, standardized dance session involving repetitive jumping, landing, and directional changes. Venous blood samples were collected before and immediately after the session to assess the sCOMP concentration. Static balance, dynamic balance, and functional performance were assessed approximately 1 week after the intervention. Group differences and associations between ΔsCOMP and relevant variables were statistically analyzed. sCOMP concentrations increased significantly from pre- to post-dance in both groups, with a significant group × time interaction (P < .001), indicating a greater post-pre increase in the CAI group. Dancers with CAI demonstrated poorer dynamic balance and functional performance than healthy control group (both P < .01), whereas no between-group difference was observed in static balance. Acute changes in sCOMP were strongly associated with ankle instability severity, as assessed using the Cumberland Ankle Instability Tool (β = -0.866, P < .001). A single standardized dance session elicited acute increases in sCOMP concentrations, with amplified responses in dancers with CAI. These findings suggest that acute cartilage metabolic responses to dance-specific loading are more closely related to ankle instability severity than balance or functional performance. sCOMP may serve as a sensitive biomarker of acute joint loading responses in dancers, underscoring the importance of considering ankle instability when interpreting cartilage-related responses to dance activity.