Kantanavar Radhakrishna, Desai Mohan Madhav, Pandit Hemant
Department of Orthopaedics, Seth G S Medical College and KEM Hospital, Parel, Mumbai, 400012 India.
Leeds Institute of Rheumatic and Musculoskeletal Medicine (LIRMM), University of Leeds, Leeds, UK.
Indian J Orthop. 2021 May 27;55(5):1135-1143. doi: 10.1007/s43465-021-00429-y. eCollection 2021 Oct.
The main purpose of this study is to assess the compatibility of medial tibial condyle (MTC) morphometry of Indian population with that of six contemporary UKA prostheses tibial components. We hypothesized that from the currently available UKA designs at least one would fit the MTC morphometry optimally as per the manufacturer's recommendation.
We used CT morphometric data of 100 (66 males and 34 females) consecutive nonarthritic adult knees with reference to the MTC to assess the compatibility of currently available (in India) UKA prostheses. Each MTC was measured in the anteroposterior dimension, mediolateral at pre-defined points and the MTC aspect ratio calculated. Proportion of knees which could be optimally fitted with the existing UKA tibial components was calculated.
The mean age was 39.6 (SD 15.9) years. Anteroposterior and mediolateral dimensions in males were higher as compared to females ( < 0.001). As the anteroposterior dimension increased, the MTC aspect ratio decreased. There was asymmetry of anteroposterior halves with maximum mediolateral width being posterior to the central mediolateral width by 5.5 (SD 2.8) mm. Optimal anteroposterior fit ranged from 66 to 93%. However, optimal mediolateral fit as well, ranged from 5 to 37% with underhang present in 17-61% and > 2 mm medial overhang present in 0-35% cases. In 23% of cases, not a single implant could be fitted optimally.
Currently available UKA implants do not provide optimal tibial fit in nearly 25% of Indian patients. A surgeon needs to be aware of these limitations of existing implants when considering UKA.
本研究的主要目的是评估印度人群的内侧胫骨髁（MTC）形态测量与六种当代单髁置换（UKA）假体胫骨部件的兼容性。我们假设，根据制造商的建议，从目前可用的UKA设计中至少有一种能最佳适配MTC形态测量。
我们使用了100例（66例男性和34例女性）连续的非关节炎成年膝关节的CT形态测量数据，以MTC为参照来评估印度目前可用的UKA假体的兼容性。测量每个MTC的前后径、在预定义点的内外侧径，并计算MTC纵横比。计算能够与现有UKA胫骨部件最佳适配的膝关节比例。
平均年龄为39.6（标准差15.9）岁。男性的前后径和内外侧径高于女性（<0.001）。随着前后径增加，MTC纵横比降低。前后半部分存在不对称，最大内外侧宽度位于中央内外侧宽度后方5.5（标准差2.8）mm。最佳前后适配范围为66%至93%。然而，最佳内外侧适配范围也为5%至37%，17%至61%存在悬垂，0%至35%的病例存在>2mm的内侧悬垂。在23%的病例中，没有一个植入物能实现最佳适配。
目前可用的UKA植入物在近25%的印度患者中不能提供最佳的胫骨适配。外科医生在考虑UKA时需要了解现有植入物的这些局限性。
