The effect of inflammatory synovial fluid on the breaking strength of new "long lasting" absorbable sutures

The effect of inflammatory synovial fluid upon several absorbable sutures potentially useful for arthroscopic procedures, e.g., meniscus repair and shoulder stabilization, was studied by implanting lengths of these sutures into unstable, arthritic rabbit knees and testing their breaking strength after varying time periods (up to 18 weeks). Polyglyconate (Maxon) sutures retained no significant strength at 6 weeks. Polydioxanone (PDS) sutures began to lose breaking strength at 3 weeks, retained only 40% of their original strength 6 weeks after implantation, and had no measurable strength at 9 weeks. Polycaprolactone (LTS) sutures showed a slow reduction in strength and retained approximately 90% of their original breaking strength after 18 weeks of implantation. Green braided polyester (Mersiline) sutures showed no loss of breaking strength over the testing period. Measurements of inherent viscosity were made to give an indirect indication of the decline in molecular weight of these sutures. These data paralleled the breaking strength decline in every case. The surgeon selecting an absorbable suture must consider the length of time the suture will hold the target tissue. This information should be helpful to surgeons considering an absorbable suture for procedures such as meniscus repair and shoulder stabilization.