Adult Reconstruction and Joint Replacement Division, Hospital for Special Surgery, New York, NY.
Department of Biomechanics, Hospital for Special Surgery, Newyork, NY.
J Arthroplasty. 2019 Apr;34(4):760-765. doi: 10.1016/j.arth.2018.12.033. Epub 2019 Jan 7.
The metaphyseal region of the bone has been recognized by its importance to the overall stability of a revision construct. Porous titanium metaphyseal sleeves to enhance biologic fixation can be used to manage bone loss encountered during revision total knee arthroplasty. While clinical results for metaphyseal sleeves are encouraging, there is little information on the extent to which biologic fixation is achievable with metaphyseal sleeves. We examined retrieved metaphyseal sleeves to determine the amount of bone ongrowth.
We studied 14 tibial and 11 femoral retrieved metaphyseal sleeves from 16 typical arthroplasty patients. Prerevision radiographs were reviewed for the presence of biologic fixation to the sleeves and the stem canal fill ratio. Bone ongrowth was assessed regionally in the anterior, posterior, medial, and lateral areas of the retrieved implants.
Bone ongrowth covered on average 14.7 ± 3.4% of the entire porous surface of the tibial sleeves. The lateral and anterior surfaces had a significantly greater proportion (P < .05) of bone ongrowth compared with the posterior and medial surfaces of the tibial components. Bone ongrowth covered on average 21.3 ± 2.6% of the entire porous surface of the femoral sleeves. No differences were found in the proportion of bone ongrowth among the posterior, medial, lateral, and anterior surfaces of the femoral. No significant association was found between the clinical, demographic, or radiographic factors and the pattern or quantity of bone ongrowth.
This study demonstrates that sufficient fixation can be achieved with only limited amounts of bone ongrowth (14.7% in tibial sleeves and 21.3% in femoral sleeves).
骨的干骺端区域因其对翻修结构整体稳定性的重要性而受到重视。多孔钛干骺端袖套可增强生物固定，用于处理翻修全膝关节置换术中遇到的骨丢失。虽然干骺端袖套的临床结果令人鼓舞，但关于干骺端袖套可实现的生物固定程度的信息很少。我们检查了取出的干骺端袖套，以确定骨长入的程度。
我们研究了 16 名典型关节置换患者的 14 个胫骨和 11 个股骨取出的干骺端袖套。回顾术前 X 线片，以确定袖套和髓腔填充率是否存在生物固定。在取出的植入物的前、后、内、外侧区域，对骨长入进行区域性评估。
胫骨袖套的整个多孔表面上，骨长入平均覆盖 14.7 ± 3.4%。与胫骨部件的后、内侧表面相比，外侧和前表面的骨长入比例显著更大（P <.05）。股骨袖套的整个多孔表面上，骨长入平均覆盖 21.3 ± 2.6%。股骨的后、内、外和前表面的骨长入比例没有差异。在骨长入的模式或数量与临床、人口统计学或影像学因素之间未发现显著相关性。
本研究表明，仅通过有限数量的骨长入（胫骨袖套为 14.7%，股骨袖套为 21.3%）即可实现足够的固定。
