Fingertip injuries

Definition

Fingertip injuries include any wounds to the area at tip of the finger. They range from a simple bruise or scrape to having the fingertip taken off. Fingertip injuries occur frequently in infants and children because hands are used to explore surroundings and play .

Description

Fingers each have three bones (phalanges); the thumb has two. The fingertip consists of the uppermost phalanx with surrounding muscle, tissue, nerves, and nail. A fingertip is a highly complex structure, with many specialized features, one of which is a rich network of sensory nerves. The fingernail is called the nail plate. Underneath the nail plate is the nail bed, the mostly pink tissue seen under the nail. The pulp is the area of skin opposite the fingernail and is usually very vulnerable to injury. Fingertip injuries are extremely common and varied. Blunt or crush injuries can cause bleeding under the nail plate (subungual hematomas), which can be very painful. Nails can also be torn off (nail avulsions), and the fingertip bone can be broken (fracture). Sharp or shearing injuries from knives and glass result in cuts (lacerations) and punctures. Occasionally, the end of the fingertip is torn off (amputated). When portions of the fingertip are missing, the injury is described as a partial amputation. When the finger is cut more than halfway through, the injury is described as a subtotal amputation. Burns and frostbite also commonly injure fingertips.

Demographics

In the United States, fingertip injuries account for approximately two-thirds of hand injuries in children. Damage to the nail bed is reported to occur in 15–24 percent of fingertip injuries. A Florida study of hand injuries in children conducted in 2002 showed that the most frequent hand injury setting was outdoors (47%). The most frequent injuries were lacerations (30%), followed by fractures (16%). The fingers were the most commonly injured part of the hand, particularly the thumb (19%), and fingertips were involved in 21 percent of cases. Children younger than two years suffered fingertip injuries mostly inside the home.

Causes and symptoms

In children, fingertip injuries are the result of accidents occurring at play or in the home. They involve cuts, by glass, knives, or other sharp objects; or crushing injuries, as when the fingertip gets caught in a door or window or is hit by a hammer or rock. Symptoms depend on the nature of the fingertip injury and may include some of the following:

• pain
• bleeding
• swelling
• tissue loss
• movement restriction
• amputation

When to call the doctor

Parents should always see a doctor right away if their child injures the tip of a finger or thumb. Fingertips contain many nerves and are extremely sensitive. Without prompt and proper care, a fingertip injury can disrupt the complex function of the hand, resulting in permanent deformity and disability. Bleeding from minor fingertip cuts often stop on its own with direct pressure applied to the wound with a clean cloth. If continuous pressure does not slow or stop the bleeding after 15 minutes, an emergency room visit is indicated.

Diagnosis

The treating physician begins a diagnosis by carefully evaluating the fingertip injury. Bones and joints are examined for motion and tenderness. Nerves are examined for sensory (feeling sensations) and motor (movement) function. As part of injury diagnosis, the treating physician also considers the following factors:

• nature of injury (crush or sharp)
• nail or nail bed involvement
• bone involvement
• viability the tip
• presence of foreign bodies

X rays may be required either to assess alignment of fingertip phalanx fractures or to detect presence of foreign bodies.

Treatment

Doctors provide individualized treatment for fingertip injuries based on the nature and extent of the injury. The treating physician usually gives an injection (digital block anesthesia) to stop pain in the affected finger. Then he or she may rinse the wound (irrigate) with a saline solution, inspect it for exposed bone, soft tissue loss, and nail or nail bed injury. Infected or dead tissue or foreign materials are also removed (debridement) to reduce risk of infection. If blood has accumulated under the nail (subungual hematoma), the doctor may drain it by piercing through the fingernail. Antibiotics and a tetanus shot may also be prescribed. The goal of treatment is a painless fingertip that has durable and feeling skin. A normal fingertip has sensation without pain, stable pulp padding, and an acceptable appearance. The hand should be able to pinch, grip, and perform other normal functions. In cases of severe injury and whenever possible, the doctor will try to maintain the fingertip's length and appearance and preserve its fingernail.

Surgery

Fingertip injuries often require surgical treatment, usually performed with local anesthesia. Fingertip repair surgery includes the following:

• Sutures: Laceration wounds are stitched (sutured) after application of a digital block.
• Nail bed surgery: If the nail bed is injured, the nail plate may be removed, the bed carefully debrided and repaired. The nail plate is then reinserted and the injury dressed. A finger splint may be applied.
• Fingertip amputation: Various methods are used for amputation injuries including simple amputation of the fingertip, full or partial skin grafts, and skin flaps.
• Reconstructive flap surgery: If a fingertip injury exposes bone, and there is not enough tissue available on the fingertip to close it, the surgeon may need to shorten the bone and transfer a piece of skin and underlying fat and blood vessels from a healthy part of the patient's body to the injury site. A bulky dressing and splint supports the hand after surgery, with uninjured fingers left free to exercise . A second operation may be necessary after a few weeks to detach the flap from its origin.
• Fractured phalanx: In case of fingertip bone fracture, the bone is straightened and put in a splint or cast. A temporary metal pin may also be inserted into the bone to hold it in place until bone growth occurs. If bone is partly missing, the finger may be shortened or the surgeon may use a bone graft.

Prognosis

The outcome depends on the extent of traumatic damage to the fingertip and whether surgery is required. Small wounds to a fingertip's skin and pulp usually close on their own with complete healing within three to five weeks. In 60 percent of patients with subungual hematomas that involve more than 50 percent of the nail surface, laceration is repairable. This prognosis increases to over 95 percent when an associated fracture of the phalanx is present. Nail lacerations that are not treated may cause nail deformities. The average healing time for fingertip amputation is 21–27 days. In many cases, fingertip repair surgery gives back a large degree of feeling and function. However, infection, poor healing, loss of feeling or motion, blood clots, and adverse reactions to anesthesia are all possible complications of surgery. Mild to severe pain and sensitivity to cold following treatment for a fingertip amputation sometimes occur.

Prevention

Children should at all times be supervised in their activities. Parents should not allow children to use sharp tools and knives without supervision. They should teach them to always wash and thoroughly dry any tool or knife before use. Children should also be taught how to use knives properly, to always cut away from themselves, and to cut in small, controlled strokes.

Parental concerns

Parents should be aware that recovery from a serious fingertip injury may take months and require hand therapy. This may include hand exercises to improve movement and strength, heat and massage therapy , electrical nerve stimulation, splinting, traction, and special wrappings to control swelling.

See also Frostbite and frostnip .

Resources

BOOKS

Ziegler, Moritz, et al. Operative Pediatric Surgery. New York:

McGraw-Hill, 2003.

PERIODICALS

Boyd, R., and C. Libetta. "Reimplantation of the nail root in fingertip crush injuries in children." Emergency Medical Journal 19, no. 2 (March 2002): 341–45.

Braga-Silva, J., and M. Jaeger. "Repositioning and flap placement in fingertip injuries." Annals of Plastic Surgery 47, no. 1 (July 2001): 60–3.

Fetter-Zarzeka, A., and M. M. Joseph. "Hand and fingertip injuries in children." Pediatric Emergency Care 18, no. 5 (October 2002): 341–45.

Wang, Q. C., and B. A. Johnson. "Fingertip injuries." American Family Physician 63, no. 10 (May 2001): 1961–66.

ORGANIZATIONS

American Academy of Orthopaedic Surgeons (AAOS). 6300 North River Road, Rosemont, IL 60018–4262. Web site: http://www.aaos.org.

American College of Surgeons. 633 N. Saint Clair St., Chicago, IL 60611–3211. Web site: http://www.facs.org.

American Society for Surgery of the Hand (ASSH). 6300 North River Road, Suite 600, Rosemont, IL 60018. Web site: http://www.assh.org.

WEB SITES

"Fingertip Injuries/Amputations." Your Orthopaedic Connection , April 2001. Available online at http://www.orthoinfo.org/fact/thr_report.cfm?Thread_ID=276&topcategory=Hand (accessed November 29, 2004).

"Fingertip Injuries." HandWorld . Available online at http://www.eatonhand.com/hw/hw011.htm (accessed November 29, 2004).

Vaughn, Glen. "Fingertip Injuries." eMedicine , November 4, 2004. Available online at http://www.emedicine.com/emerg/topic179.htm (accessed November 29, 2004).

Monique Laberge, Ph.D.