As stress builds up in the crust right before an earthquake, microfractures allow these gases to escape to the surface.

地震前，随着压力在地壳中变大，这些气体可以通过微小的裂缝溢出地表。

To a technique called microfracture, where surgeons create small holes in the bone, allowing bone marrow stem cells to leak out and form new cartilage.

还有一种微骨折的技术，在这种技术中，外科医生会在骨骼上打小孔，从而使骨髓干细胞流出并生成新的软骨。