Onychocryptosis, commonly known as ingrown nails (unguis incarnatus) or ingrowing nails, is a common form of nail disease. It is an often painful condition in which the nail grows or cuts into one or both sides of the nail bed. While ingrown nails can occur in both the nails of the hand and feet, they occur most commonly with toenails.
Symptoms of an ingrown nail include pain along the margins of the nail (caused by hypergranulation that occurs around the aforementioned region), worsening of pain when wearing shoes or other tight articles, and sensitivity to pressure of any kind, even the weight of bed sheets or a duvet. Bumping of an affected toe with objects can produce sharp, even excruciating, pain as the tissue is punctured further by the ingrown nail. By the very nature of the condition, ingrown nails become easily infected unless special care is taken to treat the condition early on and keep the area as clean as possible. Signs of infection include redness and swelling of the area around the nail, drainage of pus and watery discharge tinged with blood. The main symptom is swelling at the base of the nail on whichever side (if not both sides) the ingrowing nail is forming.
The scenarios described above are "worst case". Many ingrown toenails do not progress to an infection, and sometimes they heal themselves without intervention. However, a visit to a podiatrist is recommended if swelling is severe, if there is pus, or if the toenail remains ingrown for more than a few months.
It may not be so critical that the nails be cut perfectly 'straight across' as this may imply that they be squared at the corners. Leaving sharp square corners may be uncomfortable and cause snagging on socks. The important thing to keep in mind is that you want to be able to 'SEE' the corners. You should be able to see the side edge of the nail as it meets the front edge of the nail. This way, you can be sure there is no 'splinter' veering off to the side and growing into your toe. Careful filing of the corner is reasonable. For some people the nail curves down on the sides, in this case it would be difficult to ever see the side edge of the nail plate and this cutting method does not apply. Some nails require cutting of the corners far back to remove the edge that digs into the flesh, this may be done as a partial wedge resection at your podiatrist's office.
Ingrown toe nails can be caused by injury, commonly blunt trauma where the flesh is pressed against the nail causing a small cut that swells. Also, injury to the nail can cause it to grow abnormally, making it thicker or wider than normal or even bulged or crooked. Stubbing the toenail, dropping things on the toe and 'going through the end of your shoes' in sports are common injuries to the digits. Injuries to the toes can be prevented by wearing properly fitting shoes, especially when working or playing.
One myth is that a V should be cut in the end of the ingrown nail; this myth is untrue. The reasoning of the myth is that if one cuts a V in the nail, the edge of the nail will grow together as the nail grows out. This does not happen - the shape of the nail is determined by the growing area at the base of the toe and not by the end of the nail. A notch does no good, and may do harm if it is cut too deeply.
Some doctors will apply silver nitrate to granulation tissue (overgrowth of irritated tissue at the side of the nail. This may look like reddish cauliflower, bleeds easily). This may shrink and or remove this sensitive overgrown tissue at the side of the nail.
These home remedies are, in serious cases, ineffective: when the flesh is far too swollen and infected these procedures will not work. Thus, these more severe cases, such as when the area around the nail becomes infected or the nail will not grow back properly, must be treated by a professional and the patient should avoid repeated attempts at this type of 'bathroom surgery.'
This is known as a partial matrixectomy, phenolisation, phenol avulsion or partial nail avulsion with matrix phenolisation. Also, any infection is surgically drained. After this procedure, other suggestions on aftercare will be made, such as salt water bathing of the digit in question. The point of the procedure is that the nail does not grow back where the matrix has been cauterized and so the chances of further ingrowth are very low. The nail is slightly (usually one millimeter or so) narrower than prior to the procedure and is barely noticeable one year later. The surgery is advantageous because it can be performed in the doctor's office under local anesthesia with minimal pain following the intervention. Also, there is no visible scar on the surgery site and a nominal chance of recurrence.
Here, the digit is first injected with a common local anesthetic. When the area is numb, the physician will perform an onychotomy in which the nail along the edge that is growing into the skin is cut away (ablated) and the offending piece of nail is pulled out. Any infection is surgically drained. This process is referred to as a "wedge resection" or simple surgical ablation and is non-permanent (i.e., the nail will re-grow from the matrix). The entire procedure may be performed in a physician's office and takes approximately thirty to forty-five minutes depending on the extent of the problem. The patient is allowed to go home immediately and the recovery time is anywhere from a 2 weeks to 2 months barring any complications such as infection. As a followup, a physician may prescribe an oral or topical antibiotic or a special soak to be used for approximately a week after the surgery.
It should be noted that some physicians will not perform a complete nail avulsion (removal) under any but the most extreme circumstances. In most cases, these physicians will remove both sides of a toenail (even if one side is not currently ingrown) and coat the nail matrix on both of those sides with a chemical or acid (usually phenol) to prevent re-growth. This leaves the majority of the nail intact, but ensures that the problem of ingrowth will not re-occur.
Disadvantages: If the nail matrix is not coated with the applicable chemical or acid (phenol) and is allowed to re-grow, this method is prone to failure. Also, the underlying condition can still become symptomatic as the nail grows out over the course of up to a year: the nail matrix might be manufacturing a nail that is simply too curved, thick, wide or otherwise irregular to allow for normal growth. Furthermore, the flesh can be injured very easily by concussion, tight socks, quick twisting motions while walking or just the fact the nail is growing wrongly (likely too wide). This hypersensitivity to continued injury can mean chronic ingrowth; the solution is nearly always edge avulsion by the highly successful phenolisation.
Recurrence: If the nail becomes ingrown again after a wedge resection more invasive surgery is required. This can often include the destruction of the nail bed. This surgery takes longer than the minor wedge resection. During it the toe will be torniqued and incisions will be made from the front of the toe to around 1cm behind the rear of the visible part of the nail. These incisions are quite deep and will require stitching and will also scar. The nail will then be cut out, much like a wedge resection and the nail bed broken to prevent regrowth. The nail will be significantly narrower after this surgery and may appear visibly deformed but will not become ingrown again. Note: if undertaking this surgery it is advisable to leave at least 4 days before walking any further than very short distances as even with painkillers this can be exceedingly painful. It is also important if you are required by your employer to stand for extended periods of time that they be made aware you may be unable to work for 1-2 weeks (at most) depending on your speed of recovery.
Complete removal of the whole nail is a simple procedure. Here, anaesthetic is injected, the nail is removed quickly and painlessly and the patient can leave immediately. The entire procedure can be performed in about 10 minutes and is much less complex than a "wedge resection" as above. Note that the nail will grow back. However, in most cases it will cause further problems as it can become ingrown very easily as the nail grows outward. It can be easily injured by concussion and in some cases grows back too thick, too wide or deformed. This procedure can thus result in chronic ingrown nails and is therefore considered a generally unsuccessful solution, especially considering the pain involved.
Accordingly, in some cases as determined by a doctor, the nail matrix is coated with a chemical (usually phenol) so none of the nail will ever grow back. This is known as a permanent or full nail avulsion, or full matrixectomy, phenolisation, or full phenol avulsion. As can be seen in the images below, the nail-less toe looks much like a normal toe and fake nails or nail varnish can still be applied to the area.