THE BIOCOMPATIBILITY OF POLYETHYLENE TERE PHTHALATE PET (TREVIRA(R) HOCHFEST) - AN IN-VIVO STUDY ON SHEEP STIFLE JOINTS

The anterior cruciate ligament was transected at the femoral origin in the right stifle joint of 25 sheep. The Ligaments were re-inserted us ing the Marshall technique, and reinforced with a 3 mm band made of po lyethylene terephthalate - PET -(Trevira(R) hochfest) using the throug h-the-condyle (TTC) procedure, and re-attached - with a preload of 20 N - to the femoral and tibial condyle with two 4 mm staples. To assess the biocompatibility of the augmentation band, the synovial fluid was analysed for total protein and glucose concentration 2, 6, 24, and 56 weeks after implantation, and a total and differential cell count per formed. No significant differences were found before and after implant ation of the PET band. No pathological increase in the total protein c oncentration occurred after implantation (normal range: >3.0 g/dl), an d no significant differences vs. the preoperative analysis were found. No synovitis-signalling decrease in the glucose concentration (normal range: >40 mg/dl) was observed. The preoperative glucose concentratio n of 87 +/- 12.84 mg/dl. showed no significant difference from the pos toperative concentration of 95 +/- 13.58 mg/dl. The cytological examin ation revealed no increase in the leucocyte counts (normal range: 3 le ucocytes/HPF). Neither free nor phagocytosed wear particles were seen.