Use of small intestine submucosa in a rat model of acute and chronic rotator cuff tear.

Augmentation materials for rotator cuff tears, such as small intestine submucosa (SIS), have been used with the goal of improving outcome. Knowledge is limited on the use of SIS in animal models of acute and chronic rotator cuff tears. We hypothesized that the use of SIS in the surgical management of full thickness supraspinatus tears would improve histologic and biomechanical properties. Results show temporal improvements in several histologic parameters. Both acute and chronic injuries repaired with SIS have similar and increased mechanical properties respectively, compared to those repaired without SIS. In general, acute repairs with SIS were comparable to acute repairs without SIS. In chronic repairs, the use of SIS significantly reduced the cross sectional area of the healing tendon and increased the modulus. These results provide information on the use of SIS for rotator cuff repairs.