Crepitus is a clinical symptom in medicine that is characterized by a peculiar crackling, crinkly, or grating feeling or sound under the skin, around the lungs, or in the joints.

• 非感染性皮下气肿常见原因有肺或消化道穿孔、冲击伤、皮肤溃疡、气枪伤、拔牙和用过氧化氢冲洗伤口。