Toenail and flesh detachment may be caused by trauma, gray nails, malnutrition and other diseases. 1. Trauma: toenail and flesh detachment may be the foot suffered extrusion, impact and other traumatic injuries caused by this situation, in general, the local bruising after a certain degree of relief and absorption, can be slowly recovered. 2. Gray nails: gray nails are caused by fungi that cause damage to the nails, making them thinner and more brittle, and eventually they fall off from the nail plate and form a hollow nail, leading to detachment of the toenail from the flesh. 3. Malnutrition: If there is a lack of trace elements such as calcium, iron and zinc, it can also cause the toenail to detach from the flesh. Toenail and flesh detachment is also seen in other diseases. If the symptoms of toenail and flesh detachment persist without relief, you need to seek medical treatment in time to avoid delaying the condition.