Joint resurfacing using allograft chondrocytes and synthetic biodegradable polymer scaffolds

TLDR

Rabbit articular chondrocytes were serially passaged, cultured on fibrous polyglycolic acid scaffolds, and implanted as allografts to repair 3‑mm full‑thickness knee defects, with histological assessment over six months. In vitro, chondrocytes proliferated on PGA and produced cartilaginous matrix with higher GAG and collagen when passaged; in vivo, cell‑PGA allografts yielded superior six‑month repair compared to PGA alone, showing smoother surfaces, aligned chondrocytes, uniform GAG, restored subchondral plate, and strong bone bonding, demonstrating feasibility for joint resurfacing. © 1994 John Wiley & Sons, Inc.

Abstract

Abstract Cartilage implants which could potentially be used to resurface damaged joints were created using rabbit articular chondrocytes and synthetic, biodegradable polymer scaffolds. Cells were serially passaged and then cultured in vivo on fibrous polyglycolic acid (PGA) scaffolds. Cell‐PGA constructs were implanted in vivo as allografts to repair 3‐mm diameter, full thickness defects in the knee joints of adult rabbits, and cartilage repair was assessed histologically over 6 months. In vitro , chondrocytes proliferated on PGA and regenerated cartilaginous matrix. Collagen and glycosaminoglycan (GAG) represented 20 to 8% of the implant dry weight (dw), respectively, at the time of in vivo implantation; the remainder was PGA and unspecified components. Implants based on passaged chondrocytes had 1.7‐times as much GAG and 2.6‐times as much collagen as those based on primary chondrocytes. In vivo , cartilaginous repair tissue was observed after implantation of PGA both with and without cultured chondrocytes. Six month repair was qualitatively better for cell‐PGA allografts than for PGA alone, with respect to: (1) surface smoothness, (2) columnar alignment of chondrocytes, (3) spatially uniform GAG distribution, (4) reconstitution of the subchondral plate, and (5) bonding of the repair tissue to the underlying bone. These pilot studies demonstrate that it is feasible to use cell‐polymer allografts for joint resurfacing in vivo . © 1994 John Wiley & Sons, Inc.