And poor posture, traumas, physical activity, and strong rotational movement can cause herniations where the intervertebral disc bulges out and compress the nerves or spinal cord.

不良的姿势、创伤、体力活动和强烈的转体运动，可引起椎间盘突出，即椎间盘膨大突出于脊椎外，压迫神经或脊髓。

Hip and shoulder joints use a ball-and-socket design that allow rotational movement, but the more flexible a joint is, the more unstable and fragile it is — which is one reason why you see so many dislocated shoulders and hip replacements.

髋关节和肩关节采用球窝设计，允许旋转运动，但是关节越灵活，它就越不稳定和脆弱——这也是为什么你会看到这么多脱臼的肩膀和髋关节置换术的原因之一。