Microvascular silicon replamineform grafts of 2- and 5-cm lengths: experimental studies. Replamineform silicone microvascular grafts 1 mm in diameter were cut to clinically useful lengths (2 and 5 cm) and used to reconstruct segments of the femoral artery in the rabbit. Despite initial patency and flow rates comparable to flow seen in vein graft repairs and primary repair, no long-term patency was observed. The theoretical biomechanical advantages of this kind of graft material have not solved the problem of long microvascular grafting.