Wakabayashi Ikuko, Itoi Eiji, Minagawa Hiroshi, Kobayashi Moto, Seki Nobutoshi, Shimada Yoichi, Okada Kyoji
Department of Orthopedic Surgery, Akita University School of Medicine, Akita, Japan.
J Shoulder Elbow Surg. 2006 May-Jun;15(3):306-10. doi: 10.1016/j.jse.2005.08.022.
To clarify the relationship between the vertebral level reached by the thumb and the internal rotation angle of the humerus, 7 shoulders in healthy volunteers were examined by use of an electromagnetic tracking device. Measurements were repeated in the hanging-arm position with the thumb pointing anteriorly and at the buttock, sacrum, and each vertebral level up to T6. From the hanging-arm position to the buttock, 54.3% of internal rotation occurred (mean, 39.8 degrees ), and from the buttock to the sacrum, 11.7% occurred (mean, 8.6 degrees ). In total, 66% of internal rotation occurred from the hanging-arm position to the sacrum. Above the sacrum, the contribution of elbow flexion to the level of the vertebral spine became much greater, and internal rotation of the shoulder did not change significantly above the T12 level. We recommend that the level of the thumb below the buttock be subdivided for more accurate assessment of internal rotation.
为阐明拇指所及椎体水平与肱骨内旋角度之间的关系，我们使用电磁跟踪设备对7名健康志愿者的肩部进行了检查。在拇指朝前、指向臀部、骶骨以及直至T6的每个椎体水平的垂臂位重复进行测量。从垂臂位到臀部，发生了54.3%的内旋（平均39.8度），从臀部到骶骨，发生了11.7%的内旋（平均8.6度）。总体而言，从垂臂位到骶骨发生了66%的内旋。在骶骨上方，肘部屈曲对脊柱水平的影响变得更大，且在T12水平以上肩部内旋无明显变化。我们建议对臀部以下拇指所及水平进行细分，以便更准确地评估内旋。
