A poly(HEMA) sponge for restoration of articular cartilage defects.

The properties of poly(HEMA) sponges have been studied after implantation in the weight-bearing articular surfaces of young and adult rabbit knees. Only sponges with small pores (less than 50 micrometer) were able to withstand weight-bearing. After 12 weeks, the implants were overgrown by cartilaginous or fibrocartilaginous tissue, and the ingrowth of chondroid tissue into the sponges was observed.