Ingrown Toenail

The ingrown toenail (IGTN) has a fabulous name in medicine that is hardly used now - onychocryptosis. What do we care about the name? This is a painful condition! The -crypto suffix in the word means hidden, which is exactly what happens. A piece of nail drives into the groove (sides) and makes a tiny hole. Next, the body kicks into action and marks the site out for repair.

In this article, let's look at:

• The cause

• Self-help

• What to expect from professional treatment

The Cause of the Ingrown Toenail

Structure of the toenail

The hard nail is made from packed cells called keratin, which sits on the softer part and at the end of the toe. It comprises a nail bed and two side grooves. The grooves form gutters that we call sulci (sulk-eye) or sulcus if singular. It is within the sulci that the problem occurs. The nail builds around a small area of inflammation. Let’s deal with three scenarios.

Fig.1. Cross-section through the end of a toe to show the nail sulci (grooves) and bone (phalanx).

The shape of nails varies widely in cross-section from flat to curved, as the edges of each nail sit in the sulcus. The more curved the nail at this point, the greater the pressure against the skin, where irritation can arise. The skin responds to pressure and thickens for protection. As the bulk of skin increases, it causes discomfort as it forms callus – thicker skin layers. Some nails are very curved (U.S.A– 'incurvated'), pinching off the skin. Sometimes only one side is affected.

The incurved nail is the most common form and develops callus along the sulcus groove. The unique name – onychophosis is given to this hard skin. If you wonder about the terms used, anything starting with onycho- means nail.

Hard skin in the groove is not always painful, but given the right environment, such as a sporting activity where the great toe presses against a shoe, the nail squeezes against the groove and the underlying bone (phalanx). Pain arises with the inflammatory congestion —often erroneously called an ingrown toenail.

Abnormal curvature

Not all nails are flat in shape, which causes problems when cutting them. Some people pick at their nails, while others struggle to trim them into a more manageable shape. When either arises, nail pain is directly attributed to the nail groove or nail edge, which may become sharp.

Fig.2 One shoulder is more curved than the other side. The image is purely diagrammatic; the opposite side becomes inflamed more frequently because it takes more shoe pressure.

Break in the Skin

The nail edge penetrates the groove to create two critical conditions. Initially, the skin is inflamed, and secondly, the wound created cannot heal, and so it overreacts, producing more healing material. This tissue is called hypergranulation—fig. 3. The opposite side to the illustration is more frequently affected.

Fig.2. Traditional IGTN with hypergranulation.

Progression to pain and infection

As the skin attempts to heal, the repair process sets up a weak network of tiny vessels that, if disturbed, bleed. The colour is red and can resemble a cherry on the side or end of the toe, requiring professional help at an early opportunity.

Sweat makes matters worse and, of course, can cause that offensive smell which gives feet a lousy name.

The last ingredient that arises is infection. As long as the inflammation does not progress up the toe, this can be managed with antiseptics.

The Bridge Effect

The keratin from the skin attaches to the nail. This can arise where the top surface of the nail separates slightly. Nails grow at a rate of 0.1mm a day, so you could expect slow tension placed where the bridge effect arises.

As the nail moves forward, the resistance of the bridging effect sets up a state of inflammation as it creates a drag effect. This condition can overlap with hard skin in the nail groove (onychophosis), but is more likely to start inflammation or callus build-up. 

Self-help

Avoid damaging the groove.

Podiatrists do not recommend poking down the groove. Maybe it is not as bad as poking around in the ear, but it is difficult to see what you are doing so far down the leg. As ear professionals have specially designed instruments that minimise damage, podiatrists use similar instruments.

Adding local anaesthetic can ease discomfort and make inspection more thorough and pain-free. Digging into the sulcus is a sure way to infect the toe. Bathe the foot in warm water, add a couple of handfuls of salt or use an antiseptic solution like Chlorhexidine 25 ml in sterile sachets directly to flush the wound. Dress the wound if it discharges with something that won't stick, such as gauze treated with a shiny membrane. (Ask the pharmacist.)

If the groove has no discharge and is tender, apply an adhesive plaster around the toe, ensuring it does not restrict circulation—the toe goes white. Keep the plaster on for 48 hours and then see if the pain settles. A local antiseptic cream under the plaster keeps infection down and softens the groove.

Avoid any footwear that causes pressure or tightness. Do not go swimming or use public showers if the toe discharges. Sandals and flip-flops are perfect as long as the foot is not exposed to any other dangers.

Once the cherry-red appearance of hypergranulation has arrived, sadly, you will have lost the battle. Seek out a podiatrist. Oral antibiotics should not be used if the infection is local and the patient is healthy. Treatment can be offered to provide immediate relief.

If you want to know more about feet, check out my books - see the home page or Foot Health Myths, Facts & Fables.

Professional Treatment

Podiatrists are trained to assess your problem and provide treatment. It is not always necessary to have a minor surgery, but if this is necessary, then it can be done in a clinical setting without having to go to the hospital. The full procedure takes 20-30 minutes under local anaesthetic.

In some cases, the nail groove can be painlessly cleared without surgery, and you can then take care of the toe yourself. Pain relief is immediate. Any infection can be removed, and in some cases, the slight edge of the nail can be permanently reduced so no further regrowth arises, using a chemical. Larger sections can be removed to make the nail appear more acceptable.

Regrowth after surgery occurs in approximately 5-15% of cases because the chemical used may not penetrate the skin to kill the cells that allow nail growth. In these cases, a different surgery is used, which may entail stitches.

Return to work is usually around 24-48 hours after treatment, and recovery is typically fast. In cases where chemicals are used, slower healing can occur in some individuals, with the healing process taking several months. I have produced another article on rarer side effects following nail surgery.

Do I have to suffer pain?

If the clinician cannot provide this service, ask to see someone who can offer a local anaesthetic in an outpatient location. Only registered podiatrists or medically qualified individuals can provide local anaesthetics. If you are not provided with pain relief, and you feel you need it, then walk away. IGTN can be very painful, so do not suffer unnecessarily.

Longer term, and as an alternative strategy, nail braces can be used to aid nail curvature correction in some cases, and used where infection has been eliminated. The success depends on the extent of deformity. This technique may be useful if surgery is declined. Fig.4. shows one example as the principle of nail tensioning, but many varieties exist.

Fig.4. Nail tensioner, as in nail brace.

All podiatrists are trained to deal with IGTN and can provide a local anaesthetic to make treatment less uncomfortable. This service is available in the NHS and the independent sector.

Two podiatry organisations that look after patient foot health in the UK include: The Institute of Podiatrists & The Royal College of Podiatry.

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