Knell Sebastian C, Smolders Lucas A, Pozzi Antonio
Clinic for Small Animal Surgery, Vetsuisse Faculty University of Zurich, Zurich, Switzerland.
Front Vet Sci. 2021 Aug 16;8:706452. doi: 10.3389/fvets.2021.706452. eCollection 2021.
The objective of this study was to provide a morphometric description of the caudal cervical intervertebral disc (IVD) spaces of small-breed dogs and cats. Specimens consisting of C4 through C7 from five small-breed dogs and six cats were positioned in neutral, flexion, extension, and lateral bending positions; and CT images were acquired. Height and width of the cranial and caudal vertebral endplates (VEPs), angle between the VEPs (IVD wedge angle), and craniocaudal distance (IVD width) between VEPs for the four loading positions were measured and compared for three segments (C4-C5, C5-C6, and C6-C7). VEP size normalized to body weight from medium-sized dogs was retrieved from a previous study and compared with data from small dogs and cats. A linear mixed model was used to compare outcome measures. Significance was set to < 0.05. VEP size normalized to body weight was the largest in small dogs compared with cats ( = 0.0422) and medium-sized dogs ( = 0.0064). Cats and medium-sized dogs were similar ( = 0.2763) in this regard. Flexion and extension induced a reduction of IVD width in the ventral portion of the IVD and the area of the nucleus. The dorsal part of the IVD remained unchanged throughout loading conditions. Unique morphometric characteristics of the caudal cervical IVD space of small dogs and cats were detected that are different from those described in sizes of dogs (medium-sized) typically affected by caudal cervical spondylomyelopathy (CSM). These findings may help to understand the different pathomechanisms in cervical spinal disease between small- and medium-sized dogs, including caudal CSM.
本研究的目的是对小型犬和猫的颈尾椎间盘（IVD）间隙进行形态计量学描述。从五只小型犬和六只猫身上获取由C4至C7组成的标本，将其置于中立、屈曲、伸展和侧弯位置；并采集CT图像。测量并比较了四个加载位置下三个节段（C4 - C5、C5 - C6和C6 - C7）的头侧和尾侧椎体终板（VEP）的高度和宽度、VEP之间的角度（IVD楔角）以及VEP之间的头尾距离（IVD宽度）。从先前的一项研究中获取了按中型犬体重归一化的VEP大小，并与小型犬和猫的数据进行比较。使用线性混合模型比较结果指标。显著性设定为<0.05。与猫（P = 0.0422）和中型犬（P = 0.0064）相比，按体重归一化的VEP大小在小型犬中最大。在这方面，猫和中型犬相似（P = 0.2763）。屈曲和伸展导致IVD腹侧部分的IVD宽度和髓核面积减小。在整个加载条件下，IVD的背侧部分保持不变。检测到小型犬和猫的颈尾IVD间隙具有独特的形态计量学特征，这些特征与通常受颈尾脊髓病（CSM）影响的（中型）犬的描述不同。这些发现可能有助于理解小型犬和中型犬颈椎疾病的不同发病机制，包括尾侧CSM。
