Gene Expression Analysis in Patients With Traumatic Anterior Shoulder Instability Suggests Deregulation of Collagen Genes

Shoulder dislocation occurs in 1-2% of the population. Capsular deformation is a key factor in shoulder dislocation; however, little is known about capsule biology. We evaluated, for the first time in literature, the expression of COL1A1, COL1A2, COL3A1 and COL5A1 in the antero-inferior, antero-superior and posterior regions of the glenohumeral capsule of 31 patients with anterior shoulder instability and eight controls. the expression of collagen genes was evaluated by quantitative reverse transcription-PCR. the expression of COL1A1, COL3A1 and the ratio of COL1A1/COL1A2 were increased in all three portions of the capsule in patients compared to controls (p<0.05). COL1A2 expression was upregulated in the antero-superior and posterior sites of the capsule of patients (p<0.05). the ratio of COL1A2/COL3A1 expression was reduced in capsule antero-inferior and posterior sites of patients compared to controls (p<0.05). in the capsule antero-inferior site of patients, the ratios of COL1A1/COL5A1, CO1A2/COL5A1 and COL3A1/COL5A1 expression were increased (p<0.05). in patients, COL1A1/COL5A1 was also increased in the posterior site (p