Zone I is distal to the phalanx (bone)–There is no exposed bone and most of the nail bed is intact which will allow normal nail contours following healing. Treatment of these injuries is usually conservative, especially if the tissue loss is superficial and less than 1 cm square. The wound should then be left open to heal by secondary intention. Meticulous wound care and conservative debridement of these injuries are essential. A dressing of topical antibiotic ointments and non-adherent gauze left alone for several days will facilitate healing. Daily dressing changes can be done after the 4-5th day. As the scar contract, it will give an excellent aesthetic and functional result.
Zone II is distal to the lunula (growth matrix of the nail)–These are complicated by the bony exposure of the distal phalanx. The decision-making process begins with whether length should be preserved (necessitating coverage of the site) or whether sacrifice of length is justifiable in the given situation. The primary aim is to restore function to the individual, and many of these injuries can be converted to wounds with no bone exposed by rongeuring and then closure. If there is no possibility of direct closure, then cover can be accomplished by means of a local flap. The plane (slant of the injury) of zone II injuries helps determine what type of repair technique should be used.
Zone III is proximal to the lunula. –These involve the nail matrix and result in the entire loss of the nail bed. These injuries are most often treated by amputation (revising the end of the traumatic amputation and closing the stump). Replantations distal to the DIP are often not successful.
Atosoy-Kleinert Flap (photo)
was first described in 1970. It is a triangular volar V-Y flap advancement for reconstruction of the distal pad. It help preserve length when the bone is exposed. It is not indicated in injuries where an oblique flap with more palmar skin loss than dorsal is present.
Kutler Lateral V-Y Flap (photo)
was first described in 1944. It employs two triangular flaps developed from lateral positions and reflected to cover the tip of the digit. This is most applicable to oblique palmar and traverse tip amputations. As the V-shaped skin flap is advanced, an incision line is created which resembles a “Y” when sutured.
Volar Flap Advancement (photo)
is credited to Moberg for coverage of thumb tip amputations. It may also be used for fingertip amputations where length is to be maintained. It provides a sensible covering (has feeling) by advancing volar skin on its neurovascular pedicle. Advancement is limited to 1 cm.
Cross-Finger Pedicle Flap (photo)
was first described by Gurdin and Pangman in 1950. It is useful in distal amputation of the index finger or thumb and in situations where multiple digits are injured and maintenance of length in the remaining injured tips is considered to be of critical importance. Cross finger flap uses skin and subcutaneous tissue from the dorsum of an adjacent finger to cover the fingertip injury. The defect created by “lifting” the flap is covered with a STSG. The pedicle is left attached for 12-14 days and then divided and “tailored” into place.
Thenar Pedicle Flap (photo)
Replanted single fingers can be stiff and impede the opposition of other fingers to the thumb and overall hand function. Replanted single-finger amputations can achieve better range of motion when the level is distal to the insertion of the flexor digitorum superficialis. Single-finger replantation can be considered when patients have injuries to other fingers of the same hand. All of these injuries require splint immobilization and rehabilitation that impedes immediate return to work. Single-finger replantation can be considered in special circumstances. The surgeon must not become absorbed in the technical challenge of the replantation and neglect the other associated injuries because poorer outcomes and greater financial cost (due to lost wages and cost of hospitalization and therapy) can result.
Information & Pictures from Operative Hand Surgery, 2nd Edition, David Green MD, Churchhill Livingstone
Fingertip and Nailbed Injuries by Joseph Donnelly, MD
Fingertip Injuries by Glen Vaughn--eMedicine article
Assessment & Initial Management of Hand Injuries--Zoltan Hrabovszky