Tissue Regrowth and Its Vascularization Through Bone Marrow Stimulation: Microfracture at the Acetabular Rim for...

Area of Science:

• Orthopedic Surgery
• Regenerative Medicine
• Biomaterials Science

Background:

• Irreparable acetabular labral tears present a significant clinical challenge.
• The potential for fibrocartilage-like tissue regeneration via bone marrow stimulation remains largely unexplored.

Purpose of the Study:

• To investigate the healing process and vascularization of regenerated tissue following microfracture in a porcine model of irreparable acetabular labral tears.

Main Methods:

• Twelve pigs underwent acetabular rim microfracture after labral resection.
• Regrown tissues were evaluated macroscopically and histologically at 6 and 12 weeks.
• Vascular distribution was assessed in different zones of the regrown tissue.

Main Results:

• At 6 weeks, regenerated tissue showed early fibrocartilage formation with good vascularization but insufficient defect filling.
• By 12 weeks, tissue disintegration occurred, with reduced defect filling and vascularity.
• Early stages demonstrated proteoglycan and collagen deposition, which diminished by 12 weeks.

Conclusions:

• While bone marrow stimulation promotes early vascularized fibrocartilage-like tissue regrowth, the volume is insufficient to restore labral function.
• Microfracture alone does not restore acetabular labrum morphology and function.
• Microfracture may serve as an adjunct in labral reconstruction, potentially improving graft vascularization.