Dickinson A S, Steer J W, Rossides C, Diment L E, Mbithi F M, Bramley J L, Hannett D, Blinova J, Tankard Z, Worsley P R
Faculty of Engineering & Physical Sciences, University of Southampton, Southampton, United Kingdom.
Radii Devices Ltd., Bristol, United Kingdom.
Front Rehabil Sci. 2024 Jul 12;5:1354069. doi: 10.3389/fresc.2024.1354069. eCollection 2024.
Transtibial prosthetic sockets are often grouped into patella tendon bearing (PTB) or total surface bearing (TSB) designs, but many variations in rectifications are used to apply these principles to an individual's personalised socket. Prosthetists currently have little objective evidence to assist them as they make design choices.
To compare rectifications made by experienced prosthetists across a range of patient demographics and limb shapes to improve understanding of socket design strategies.
163 residual limb surface scans and corresponding CAD/CAM sockets were analysed for 134 randomly selected individuals in a UK prosthetics service. This included 142 PTB and 21 TSB designs. The limb and socket scans were compared to determine the location and size of rectifications. Rectifications were compiled for PTB and TSB designs, and associations between different rectification sizes were assessed using a variety of methods including linear regression, kernel density estimation (KDE) and a Naïve Bayes (NB) classification.
Differences in design features were apparent between PTB and TSB sockets, notably for paratibial carves, gross volume reduction and distal end elongation. However, socket designs varied across a spectrum, with most showing a hybrid of the PTB and TSB principles. Pairwise correlations were observed between the size of some rectifications (e.g., paratibial carves; fibular head build and gross volume reduction). Conversely, the patellar tendon carve depth was not associated significantly with any other rectification, indicating its relative design insensitivity. The Naïve Bayes classifier produced design patterns consistent with expert clinician practice. For example, subtle local rectifications were associated with a large volume reduction (i.e., a TSB-like design), whereas more substantial local rectifications (i.e., a PTB-like design) were associated with a low volume reduction.
This study demonstrates how we might learn from design records to support education and enhance evidence-based socket design. The method could be used to predict design features for newly presenting patients, based on categorisations of their limb shape and other demographics, implemented alongside expert clinical judgement as smart CAD/CAM design templates.
经胫骨假肢接受腔通常分为髌腱承重（PTB）或全表面承重（TSB）设计，但在将这些原则应用于个体定制接受腔时，有许多不同的修正方法。目前，假肢矫形师在做出设计选择时几乎没有客观证据可供参考。
比较经验丰富的假肢矫形师针对一系列患者人口统计学特征和肢体形状所做的修正，以增进对接受腔设计策略的理解。
对英国一家假肢服务机构中随机选取的134名个体的163次残肢表面扫描及相应的计算机辅助设计/计算机辅助制造（CAD/CAM）接受腔进行了分析。其中包括142个PTB设计和21个TSB设计。将肢体扫描和接受腔扫描进行比较，以确定修正的位置和大小。整理了PTB和TSB设计的修正情况，并使用包括线性回归、核密度估计（KDE）和朴素贝叶斯（NB）分类在内的多种方法评估了不同修正大小之间的关联。
PTB和TSB接受腔在设计特征上存在明显差异，特别是在胫骨旁雕刻、总体积减小和远端延长方面。然而，接受腔设计多种多样，大多数呈现出PTB和TSB原则的混合。在一些修正的大小之间观察到了成对相关性（例如，胫骨旁雕刻；腓骨头塑形和总体积减小）。相反，髌腱雕刻深度与任何其他修正均无显著关联，表明其相对设计不敏感。朴素贝叶斯分类器产生的设计模式与临床专家的实践一致。例如，细微的局部修正与大量体积减小相关（即类似TSB的设计），而更显著的局部修正（即类似PTB的设计）与少量体积减小相关。
本研究展示了我们如何从设计记录中学习，以支持教育并加强基于证据的接受腔设计。该方法可用于根据新就诊患者的肢体形状和其他人口统计学特征分类，预测其设计特征，并与专家临床判断一起作为智能CAD/CAM设计模板实施。
