FasT-Fix Versus Inside-Out Suture Meniscal Repair in the Goat Model

Background: Recent all-inside meniscal repair devices are available, but in vivo studies with these devices are sparse. Hypothesis: The FasT-Fix has inferior meniscal healing compared with the inside-out suture technique in the goat model. Study Design: Controlled laboratory study. Methods: After Institutional Review Board approval, 73 male castrated goats (Capra hircus) underwent a 2-cm meniscal incision and subsequent repair with the FasT-Fix device on one knee and inside-out meniscal repair on the contralateral knee. Both repairs used a vertical mattress suture technique. Access to the menisci was via an open technique with an extra-articular osteotomy of the medial collateral ligament origin on the femur. The animals were then allowed to ambulate unrestricted in a pasture after a 7-day stay in cages. Necropsy was carried out 6 months postoperatively, and the menisci and articular cartilage were studied with gross and microscopic inspection. Results: Nine of the 73 animals were excluded before necropsy. A total of 64 animals underwent necropsy, gross measurement of residual lesions, gross evaluation for chondral damage, histologic evaluation of meniscal repair, histologic evaluation of any adjacent inflammatory reaction to implants, and data analysis. Compared with the inside-out group, the FasT- Fix group had longer residual full- thickness defects (1.2 +/- 2.9 mm vs 0.2 +/- 1.1 mm; P = .011) and longer residual partial- thickness defects (8.4 +/- 6.3 mm vs 3.6 +/- 5.5 mm; P <.001). A total of 148 FasT-Fix devices were placed for 73 knees. Two devices were replaced for improper deployment. The device deployed and attached correctly 146 of 148 times for a success rate of 98.6%. There was no gross chondral damage and no histologic findings of inflammatory reaction to the implants with either technique. Conclusions: The FasT-Fix meniscal repair had inferior meniscal healing results in this animal model. Previous studies using this animal model have paralleled clinical outcomes. Implantation of the FasT-Fix device does not damage adjacent femoral or tibial cartilage. The deployment of the FasT-Fix implant was simple and reproducible. There was no inflammatory reaction to the FasTFix implant. Clinical Relevance: The FasT-Fix meniscal repair has inferior meniscal healing results compared with the inside- out meniscal repair technique in the goat model. The clinical significance of this finding is not known. Further clinical study of the FasT- Fix implant is warranted.