| 摘要 |
An abdominal/back muscle member 19 tightly surrounds narrowed portions 172 and 182 of an upper and a lower body members 17 and 18 of a lumbar assembly of human lumbar model structure. Shoulders 173 and 183 are formed at the bounds of the narrowed portion 172 and 182 from the remaining upper and lower portions of the upper body member and the lower body member 17 and 18 with a radial height larger than the thickness of the abdominal/back muscle member 19 to form hood-like radial flanges protruding from the outer upper and lower edges of the muscle member. The hood-like radial flanges effectively prevent the upper and lower edges of the muscle 19 from going over the shoulders, even if the maximum vertical loading is applied to the structure. In the human lumbar model structure, a lower element 112 of an upper lumbar member 11 is formed with a penetration path 34, which axially extends therein and communicates with an inner cavity of an annulus fibrosus member 13 filled with the nucleus pulposus liquid 16 inside. The liquid can overflow the penetration path until the pressure of the nucleus pulposus liquid 16 becomes to an appropriate value.
|
