Department of Surgery and Department of Laboratory Medicine & Pathobiology, University of Toronto, Toronto, Ontario, Canada.
Lunenfeld Tanenbaum Research Institute, Sinai Health System, Toronto, Ontario, Canada.
J Orthop Res. 2022 Oct;40(10):2294-2307. doi: 10.1002/jor.25272. Epub 2022 Feb 11.
Two commercially available porous coatings, Gription and Porocoat, were compared for the first time in a challenging intra-articular, weight-bearing, ovine model. Gription has evolved from Porocoat and has higher porosity, coefficient of friction, and microtextured topography, which are expected to enhance bone ingrowth. Cylindrical implants were press-fit into the weight-bearing regions of ovine femoral condyles and bone ingrowth and fixation strength evaluated 4, 8, and 16 weeks postoperatively. Biomechanical push-out tests were performed on lateral femoral condyles (LFCs) to evaluate the strength of the bone-implant interface. Bone ingrowth was assessed in medial femoral condyles (MFCs) as well as implants retrieved from LFCs following biomechanical testing using backscattered electron microscopy and histology. By 16 weeks, Gription-coated implants exhibited higher force (2455 ± 1362 vs. 1002 ± 1466 N; p = 0.046) and stress (12.60 ± 6.99 vs. 5.14 ± 7.53 MPa; p = 0.046) at failure, and trended towards higher stiffness (11,510 ± 7645 vs. 5010 ± 8374 N/mm; p = 0.061) and modulus of elasticity (591 ± 392 vs. 256 ± 431 MPa; p = 0.061). A strong, positive correlation was detected between bone ingrowth in LFC implants and failure force (r = 0.93, p < 10 ). By 16 weeks, bone ingrowth in Gription-coated implants in MFCs was 10.50 ± 6.31% compared to 5.88 ± 2.77% in Porocoat (p = 0.095). Observations of the bone-implant interface, made following push-out testing, showed more bony material consistently adhered to Gription compared to Porocoat at all three time points. Gription provided superior fixation strength and bone ingrowth by 16 weeks.
两种市售多孔涂层 Gription 和 Porocoat 首次在挑战性的关节内承重绵羊模型中进行了比较。Gription 是从 Porocoat 发展而来的，具有更高的孔隙率、摩擦系数和微观形貌，预计能增强骨长入。将圆柱形植入物压入绵羊股骨髁的承重区，术后 4、8 和 16 周评估骨长入和固定强度。对外侧股骨髁（LFC）进行生物力学推出试验，以评估骨-植入物界面的强度。在生物力学试验后，通过背散射电子显微镜和组织学评估内侧股骨髁（MFC）中的骨长入以及从 LFC 中取出的植入物。到 16 周时，Gription 涂层植入物的失效力（2455 ± 1362 N 与 1002 ± 1466 N；p = 0.046）和失效时的应力（12.60 ± 6.99 MPa 与 5.14 ± 7.53 MPa；p = 0.046）更高，且显示出更高的刚度（11510 ± 7645 N/mm 与 5010 ± 8374 N/mm；p = 0.061）和弹性模量（591 ± 392 MPa 与 256 ± 431 MPa；p = 0.061）的趋势。LFC 植入物的骨长入与失效力之间存在强烈的正相关性（r = 0.93，p < 10）。到 16 周时，MFC 中 Gription 涂层植入物的骨长入率为 10.50 ± 6.31%，Porocoat 为 5.88 ± 2.77%（p = 0.095）。推出试验后对骨-植入物界面的观察显示，与 Porocoat 相比，Gription 始终有更多的骨材料附着。到 16 周时，Gription 提供了更好的固定强度和骨长入。
