Carbon fiber debris within the synovial joint. A time-dependent mechanical and histologic study

The consequences of release of carbon debris within the synovial joint are of interest to surgeons contemplating the intra-articular repair of cruciate-deficient knees with a carbon fiber-based material. Coverage of carbon fiber implants with absorbable polymer as well as autogeneic graft material has resulted in surgical procedures that minimize potential fiber release. However, finite risk of release of fiber debris certainly exists. With this in mind, a controlled animal experiment to model debris release in the synovial joint was performed. As a positive control, magnesium tetrasilicate (talc) in suspension was injected into the knees of rabbits. Talc produced a transient synovitis severe enough to alter the mechanical properties of the joint cartilage. Carbon fiber debris, when similarly injected, also produced a synovitis. However, the synovitis induced by carbon particulate was not of sufficient severity or duration to alter the mechanical properties of the cartilage. Neither talc nor carbon fiber debris appeared to physically abrade cartilage.