RESUMEN
Biomechanical testing was performed to determine isometric interosseous ligament graft placement as a preliminary step for reconstruction after an axial forearm disruption. Twenty-five combinations of potential ligament graft placement were studied on 7 fresh-frozen cadavers. Suture was used to simulate these potential ligament reconstructions, and suture excursion was used as an index of isometry. Ligament orientation was defined by the angle formed between the ulna and the suture (surrogate graft). Ligament position was defined by its insertion on the ulna as a percentage of ulna length. Suture-ulna angles from 9 degrees to 38 degrees produced significantly less suture excursion than angles of > or = 39 degrees. Minimal suture excursion was noted at angles of < or = 20 degrees, which we feel represents the optimal range for reconstruction. The optimal location on the ulna for isometric interosseous ligament reconstruction was at 25% to 30% of total ulna length, as measured proximally from the distal ulna articular surface. The radius isometric location is optimally located by a vector starting from the ulna isometric point and directed toward the proximal radius at an angle of < or = 20 degrees relative to the long axis of the ulna. Interosseous ligament reconstruction may prove beneficial in the long-term outcome of reconstruction after axial forearm disruption.
Asunto(s)
Antebrazo/anatomía & histología , Ligamentos/anatomía & histología , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos , Cadáver , Femenino , Humanos , Masculino , Radio (Anatomía)/anatomía & histología , Distribución Aleatoria , Valores de Referencia , Rotación , Suturas , Cúbito/anatomía & histologíaRESUMEN
The polytetrafluoroethylene (PTFE) vascular prosthesis is thrombogenic and therefore not an ideal artificial blood vessel. The immobilization of urokinase on the surface of this substance has the potential to render the PTFE thrombolytic. Urokinase was immobilized to PTFE using tridodecylmethyl-ammonium chloride as a surfactant. In this preliminary study, a success rate of 45 percent was observed for the immobilization of active urokinase to PTFE. A model is proposed wherein application of the graft to an in vivo system is discussed. The urokinase graft is expected to be most effective under conditions of reduced blood flow which otherwise might promote thrombogenesis. The systemic side effects of the immobilized urokinase are expected to be significantly less when compared with the side effects of urokinase infused for clot lysis. The model presented of the urokinase-bound graft suggests that development and further study of the graft will result in an improved PTFE vascular prosthesis.