Abstract
Purpose
To assess performance of a polyurethane scaffold designed to facilitate regrowth of tissue after irreparable partial meniscus tissue loss.
Methods
Fifty-two subjects with irreparable medial or lateral meniscus tissue lesions with intact rim, presence of both horns and stable, well aligned knees, were treated with the scaffold. Tissue ingrowth was assessed using dynamic contrast enhanced MRI (DCE-MRI) at 3 months (n=43), and by histological examination of biopsies (n=44) at 12 months relook arthroscopy. Cartilage status on MRI at 1week, 3, 12 and 24 months, and clinical outcomes were assessed from baseline to 24 months using Visual Analogue Scale (VAS), Knee and Osteoarthritis Outcome Score (KOOS), Lysholm and International Knee Documentation Committee (IKDC).
Results
Clinically and statistically significant improvements on all outcome scores were observed at 6, 12 and 24 months.
On MRI, stable or improved ICRS scores in all but 3 subjects (n=40) at 24 months were observed, with no signs of scaffold related cartilage damage. All biopsies contained vital material, with no signs of necrosis, cell death (presence of cell pods, ghost cells, cells with defragmented nuclei), or adverse reaction to the scaffold or its degradation products. A fibrous capsule and three distinct layers were observed, each with its own unique histological characteristics, including presence or absence of vessel structures, and the composition of extracellular matrix.
In one case with unknown causality, the scaffold did not integrated with the native tissue. No safety issues related to the scaffold were reported.
Conclusions
These data demonstrate the safety and performance of the polyurethane scaffold and illustrate new tissue generation resulting in significant pain reduction and functional improvement.
