Institute for Biomedical Engineering, University of Rostock, F. Barnewitz-Str, 4, D-18119 Rostock, Germany.
BMC Musculoskelet Disord. 2012 Feb 9;13:14. doi: 10.1186/1471-2474-13-14.
It is often suggested that sagittal instability at the first tarso-metatarsal joint level is a primary factor for hallux valgus and that sagittal instability increases with the progression of the deformity. The assessment of the degree of vertical instability is usually made by clinical evaluation while any measurements mostly refer to a static assessment of medial ray mobility (i.e. the plantar/dorsal flexion in the sagittal plane). Testing methods currently available cannot attribute the degree of mobility to the corresponding anatomical joints making up the medial column of the foot. The aim of this study was to develop a technique which allows for a quantification of the in-vivo sagittal mobility of the joints of the medial foot column during the roll-over process under full weight bearing.
Mobility of first ray bones was investigated by dynamic distortion-free fluoroscopy (25 frames/s) of 14 healthy volunteers and 8 patients with manifested clinical instability of the first ray. A CAD-based evaluation method allowed the determination of mobility and relative displacements and rotations of the first ray bones within the sagittal plane during the stance phase of gait.
Total flexion of the first ray was found to be 13.63 (SD 6.14) mm with the healthy volunteers and 13.06 (SD 8.01) mm with the patients (resolution: 0.245 mm/pixel). The dorsiflexion angle was 5.27 (SD 2.34) degrees in the healthy volunteers and increased to 5.56 (SD 3.37) degrees in the patients. Maximum rotations were found at the naviculo-cuneiform joints and least at the first tarso-metatarsal joint level in both groups.
Dynamic fluoroscopic assessment has been shown to be a valuable tool for characterisation of the kinematics of the joints of the medial foot column during gait.A significant difference in first ray flexion and angular rotation between the patients and healthy volunteers however could not be found.
人们常认为第一跖跗关节水平矢状面不稳定是导致拇外翻的主要因素，且畸形进展会导致矢状面不稳定性增加。垂直不稳定性的评估通常通过临床评估进行，而大多数测量值主要是对内侧射线活动度的静态评估（即矢状面的跖屈/背屈）。目前可用的测试方法无法将活动度归因于构成足内侧柱的相应解剖关节。本研究旨在开发一种技术，该技术可在完全负重的情况下，在翻滚过程中对内侧足柱关节的矢状面活动度进行定量测量。
通过对 14 名健康志愿者和 8 名第一跖骨临床不稳定的患者进行 25 帧/秒的动态无失真荧光透视检查，研究第一跖骨的活动度。基于 CAD 的评估方法允许确定在步态的站立阶段，第一跖骨骨在矢状面内的活动度以及相对位移和旋转。
健康志愿者的第一跖骨总屈曲度为 13.63（SD 6.14）mm，患者为 13.06（SD 8.01）mm（分辨率：0.245mm/像素）。健康志愿者的背屈角为 5.27（SD 2.34）度，患者增加至 5.56（SD 3.37）度。两组中，最大旋转发生在舟楔关节，而在第一跖跗关节水平处最小。
动态荧光透视评估已被证明是一种有价值的工具，可用于在步态过程中对内侧足柱关节运动学进行特征描述。然而，在患者和健康志愿者之间，第一跖骨的屈曲和角度旋转没有显著差异。
