Research Unit of Medical Imaging, Physics and Technology, Faculty of Medicine, University of Oulu, Oulu, Finland.
Medical Research Center, University of Oulu, Oulu, Finland.
Equine Vet J. 2020 Jan;52(1):152-157. doi: 10.1111/evj.13132. Epub 2019 Jun 6.
In horses, osteoarthritis (OA) mostly affects metacarpophalangeal and metatarsophalangeal (fetlock) joints. The current modalities used for diagnosis of equine limb disorders lack ability to detect early OA. Here, we propose a new alternative approach to assess experimental cartilage damage in fetlock joint using Acoustic Emissions (AE).
To evaluate the potential of AE technique in diagnosing OA and see how AE signals changes with increasing severity of OA.
An in vitro experimental study.
A total of 16 distal limbs (8 forelimbs and 8 hindlimbs) from six Finn horses were collected from an abattoir and fitted in a custom-made frame allowing fetlock joint bending. Eight fetlock joints were opened, and cartilage surface was progressively damaged mechanically three times using sandpaper to mimic mild, moderate and severe OA. The remaining eight fetlock joints were opened and closed without any mechanical procedure, serving as controls. Before cartilage alteration, synovial fluid was aspirated, mixed with phosphate-buffered saline solution, and then reinjected before suturing for constant joint lubrication. For each simulated condition of OA severity, a force was applied to the frame and then released to mimic joint flexion and extension. AE signals were acquired using air microphones.
A strong association was found between the joint condition and the power of AE signals analysed in 1.5-6 kHz range. The signal from both forelimb and hindlimb joints followed a similar pattern for increased cartilage damage. There were statistically significant differences between each joint condition progressively (generalised linear mixed model, P<0.001) in limbs with in vitro cartilage damage of varying severity while the control limbs did not show any changes.
Small sample size using in vitro, mechanically induced cartilage damage.
The AE technique presented here could differentiate the severity of fetlock joint cartilage damage. The consistent results for each simulated condition suggest there is potential for this method in the diagnosis of OA.
在马中，骨关节炎（OA）主要影响掌指和跖趾（球节）关节。目前用于诊断马肢疾病的方法缺乏早期 OA 的检测能力。在这里，我们提出了一种新的替代方法，即使用声发射（AE）评估球节关节的实验性软骨损伤。
评估 AE 技术诊断 OA 的潜力，并观察 AE 信号如何随 OA 严重程度的增加而变化。
一项体外实验研究。
从一个屠宰场收集了 6 匹芬兰马的 16 个跗关节（8 个前肢和 8 个后肢），并将其安装在一个定制的框架中，允许球节关节弯曲。8 个球节关节被打开，软骨表面使用砂纸机械地进行了三次损伤，以模拟轻度、中度和重度 OA。其余 8 个球节关节在没有任何机械程序的情况下打开和关闭，作为对照。在软骨改变之前，抽吸滑膜液，与磷酸盐缓冲盐水混合，然后在缝合前重新注入以保持关节润滑。对于模拟的每种 OA 严重程度，对框架施加力然后释放以模拟关节屈伸。使用空气传声器采集 AE 信号。
在 1.5-6 kHz 范围内分析的关节状况与 AE 信号的功率之间存在很强的相关性。前肢和后肢关节的信号都遵循类似的模式，随着软骨损伤的增加而增加。在具有不同严重程度的体外软骨损伤的肢体中，每个关节状况之间存在统计学上的显著差异（广义线性混合模型，P<0.001），而对照肢体没有显示出任何变化。
使用体外、机械诱导的软骨损伤的样本量小。
这里提出的 AE 技术可以区分球节关节软骨损伤的严重程度。每种模拟情况的一致结果表明，该方法有可能用于 OA 的诊断。
