Anatomy of Feet, Toes, and Toenails

Nearly one-fourth of all bones in the human body are in the feet. The foot is a complex, flexible structure that contains bones, joints, and more than 100 muscles, tendons and ligaments, all working together to enable movement and balance. The foot is divided into three sections, the forefoot, the midfoot and the hindfoot. The forefoot has five toes (14 phalanges) and five longer bones (metatarsals). One phalanx of each of the five toes connects to one of the five metatarsals. Each of the four lesser digits, or smaller toes, contains three joints.

The tip of each toe is protected from injury and infection by a toenail, which is made of keratin, a fibrous, amino acid protein that is also present in the fingernails, hair and skin.

Nail plate—The hard, visible part of the nail that grows longer and requires trimming

Nail matrix—Structure at the nail base, where new toenails form

Nail fold—Soft tissue border around the nail plate; helps protect the edges of the nail plate and nail matrix from trauma and ultraviolet radiation

Nail bed—Tissue and skin under the nail plate that supports healthy nail growth and secures the place

Cuticle—Seal of soft tissue at the nail base that grows from the nail bed and attaches to the nail plate

Hyponychium—Skin under the free edge of the nail plate, at the very tip of the toe

Onychodermal band—Seal of tissue that marks where the nail plate separates from the hyponychium

What is an Ingrown Toenail?

An ingrown toenail (onychocryptosis or unguis incarnates) occurs when the corner or side of a toenail grows into the soft skin surrounding it, causing pain, inflammation, swelling, redness, and even infection. This is a common condition that most often affects the big toe. In some cases, new tissue begins to grow over the ingrown nail (granuloma) and the area of inflammation weeps, bleeds, releases pus, and produces a bad odor.

Ingrown toenails have three stages of severity:

Stage 1—The toenail grows into the skin, causing pain and inflammation

Stage 2—New tissue grows over the edges of the ingrown nail (granuloma); the area of inflammation weeps and produces pus

Stage 3—Skin surrounding the toenail is chronically inflamed and continuously oozes pus; the granuloma is growing over the nail

Causes and Risk Factors

  • Wearing tight shoes, or shoes with pointed toes
  • Cutting the nail too short, cutting the corners, or rounding the edges—instead of trimming the nail straight across
  • Having sweaty feet
  • Certain inherited toenail shapes, including highly curved or pincer nails, or thick nails
  • Being overweight or obesity
  • Having diabetes, which can lead to conditions such as water retention in the feet, heart or kidney failure, or chronic venous insufficiency in the legs
  • Certain cancer medications
  • Although anyone can develop an ingrown toenail, they occur most often in teenagers, young adults and older people

When to Seek Immediate Care

If you have diabetes or another condition that causes poor blood flow or lack of feeling in the feet, or you’re experiencing severe discomfort, producing pus, or the inflamed area is spreading, it’s important to see your podiatrist immediately. Prompt treatment is necessary to avoid complications.

Treating an Ingrown Toenail

Ingrown toenails are usually noticed early on because they’re painful. If the inflammation is mild, soak the foot in a warm, soapy footbath (about 15 minutes), dry the foot thoroughly, then treat the ingrown nail with an antiseptic or anti-inflammatory gel, cream or tincture. Waiting a few minutes before putting on comfortable, loose-fitting, or open-toed footwear. Avoid putting any pressure on the ingrown toenail. If the inflammation or pain worsens, or there is no improvement, see your podiatrist or foot specialist.

Depending on the severity of your ingrown toenail, your podiatrist may recommend one of the following treatments:

Lift the toenail—The nail is separated from overlying skin by lifting the ingrowing nail edge and lacing cotton, dental floss, or a splint beneath it. This allows the nail to grow above the skin edge, typically in 12 weeks or less.

Tape the toenail—Tape is used to pull the skin away from the ingrown nail.

Gutter splint—After numbing the toe, a tiny slit tube is inserted under the embedded nail where it remains until the nail has grown above the skin’s edge. This can also help to lessen the pain.

Partial toenail removal—For more severe ingrown nails, the toe is numbed and a portion of the ingrown nail trimmed or removed. The toenail typically grows back within 2 to 4 months.

Removal of toenail and surrounding tissue—Your podiatrist may recommend this treatment for severe and repeated problems with a particular toe. During this procedure, the toe is numbed and a laser, chemical, or other method is used to remove part of the toenail along with the underlying tissue or nail bed, which will prevent that area of the nail from growing back.

Following a toenail removal procedure, rest and elevate the foot for 12 to 24 hours. You may take a nonprescription pain reliever as directed, if needed. Your podiatrist may also recommend application of a wet compress for a few minutes, until the swelling goes down. Although you may shower the day after your surgery, do not use a hot tub or go swimming until your physician approves the activity.