Laser effects on fibrin clot response by human meniscal fibrochondrocytes in organ culture

Fibrin mixtures are currently under investigation for their ability to stimulate and maintain a reparative response in the avascular portion of the meniscus. A major problem with this technology is the inadequate adhesive strength of conventional fibrin clot mixtures. Argon laser assisted fibrin clot bonding (LAFCB) has been shown to increase the tensile strength of the meniscal-fibrin clot bond over 40 fold; however, LAFCB effect on fibrin clot's ability to stimulate meniscal repair has not been studied. Using in vitro tissue culture, the effects of diode laser energy on fibrin clot's ability to stimulate repair of 2 mm punch hole defects in human menisci is investigated. Four groups were created in each meniscus. Dye enhanced fibrin clot with (group I) and without (group II) exposure to 9.6 watts/cm 2 of continuous wave diode ion laser energy was used to fill 2.0 mm punch hole defects created in human menisci. Group III consisted of defects with fibrin clot alone. Unfilled defects served as controls (group IV). In vitro tissue culture was utilized to maintain meniscal viability. Specimens were analyzed at weekly intervals for eight weeks. All clots were grossly displaced from the punch hole defects within the first week except those in group I. Histologic evaluation revealed that exposure to diode laser energy stabilized fibrin clot. In no group was fibrochondrocyte migration or proliferation observed. These findings support a possible method of fibrin clot stabilization; however, further work is necessary to identify and overcome obstacles to fibrochondrocyte migration which could obviate the need for partial menisectomy and its subsequent degenerative effects.