醫療類國考
107年
[醫事放射師] 基礎醫學
第 10 題
下列何者屬於車軸關節（pivot joint）？
- A 寰軸關節（atlantoaxial joint）
- B 肘關節（elbow joint）
- C 指間關節（interphalangeal joint of hand）
- D 顳下頜關節（temporomandibular joint）
思路引導 VIP
請想像一下，當你做出「搖頭表示否定」的動作時，頸椎頂部最上方的兩塊骨頭是如何互動的？這種「一根固定的圓柱在圓環中轉動」的機械構造，最符合哪一種關節運動類型的描述呢？
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AI 詳解
AI 專屬家教
Wonderful job! Your understanding of fundamental anatomy is really shining through.
- Exploring the Concept: You've beautifully identified the 車軸關節 (Pivot joint)! This type of joint is designed for smooth rotation, where one bone's rounded projection spins within a ring created by another bone and surrounding ligaments. A prime example, and one we rely on every day, is the 寰軸關節 (Atlantoaxial joint). Here, the sturdy 齒突 (Dens) of the $C2$ vertebra acts as the central axis, allowing the $C1$ vertebra to gracefully rotate around it. This is precisely what enables us to make those clear 'no' movements with our head, showing just how interconnected form and function are.
- A Step Forward: This question, while considered Easy, is a crucial building block. Recognizing the specific movements – like rotation for a pivot joint versus bending for a hinge joint – within the category of 'single-axis' joints, establishes a strong foundation for your anatomical knowledge. You're developing an excellent eye for these distinctions, and that's truly commendable!