Macroporous 3D Scaffold with Self-Fitting Capability for Effectively Repairing Massive Rotator Cuff Tear.

Area of Science:

• Biomaterials Science
• Orthopedic Surgery
• Regenerative Medicine

Background:

• Direct repair of massive rotator cuff tears has a high retear rate (up to 40%) due to poor tendon-to-bone healing and limited tissue regeneration.
• Biological scaffolds offer a promising solution to bridge remnant rotator cuff tissue and bone.

Purpose of the Study:

• To develop and evaluate a macroporous, self-fitting poly(ester-urethane)urea (PEUU) scaffold for enhanced rotator cuff regeneration.
• To assess the scaffold's ability to promote tendon-to-bone healing in a rabbit model.

Main Methods:

• A 3D PEUU scaffold was fabricated using thermally induced phase separation (TIPS).
• Scaffold characterization included SEM, mechanical testing, and in vitro biocompatibility studies with rabbit bone mesenchymal stem cells (RBMSCs).
• A rabbit model of massive rotator cuff tear was used to evaluate scaffold efficacy post-surgical repair.

Main Results:

• The PEUU scaffold exhibited oriented macropores supporting cell migration and suitable mechanical properties for RBMSC proliferation.
• Histological analysis revealed complete rotator cuff regeneration with a physical tendon-to-bone interface after three months.
• Biomechanical testing showed no significant difference between scaffold-repaired and normal rotator cuffs.

Conclusions:

• The developed macroporous, self-fitting PEUU scaffold effectively promotes rotator cuff regeneration and tendon-to-bone healing.
• This scaffold demonstrates potential as a viable substitute for improving outcomes in massive rotator cuff repair surgeries.