An ingrowing toenail is a common condition in which one or both sides of the great toenail turn downwards and start to dig into the flesh of the nail fold. This causes pain and can become infected. Ingrowing toenails can be caused by pressure of foot-wear, poor nail care or direct injury.
Pincer nail is a related condition in which the whole nail becomes arched in cross section, in addition to ingrowing at the edges. This is usually caused by a small spur of bone on the distal phalanx pushing upwards on the nail.
Ingrowing nails may be treated with regular chiropody, antibiotics if infected, or surgery. This usually takes the form of a wedge resection in which a narrow strip of the ingrowing nail is removed and the growing cells at the corner of nail killed with phenol to prevent re-growth. If deep infection or bone spurs are present the abnormal segments of bone may be removed. If the problem keeps recurring it may be better to remove the nail completely.