Fingertip Amputation

Updated: Aug 30, 2021

Author: Palaniappan Lakshmanan, MBBS, MS, AFRCS, FRCS(Tr&Orth); Chief Editor: Erik D Schraga, MD

Overview

Background

Fingertip injuries are among the most common injuries of the hand, and appropriate treatment depends on the type of injury and the involvement of other digits.

Fingertip amputation occurs distal to the insertion of flexor or extensor tendons into the distal phalanx. Numerous techniques are available for the repair of fingertip amputations, with the common goal of reducing pain and preserving sensation at the tip (see Technique).[1, 2] The appropriate approach depends on the amount of tissue involved, the involvement of bone (distal phalanx), the angles and levels of amputation, and the involvement of other fingers or the rest of the hand.

Techniques discussed in this article are as follows:

Open technique (nonoperative; healing by secondary intention)
Skin graft
Reamputation
V-Y flap (Kutler or Atasoy)
Volar flap advancement (Moberg) ^[3]
Bipedicle dorsal flap
Crossfinger flap
Thenar flap

Fingertip replantation has become an established technique with the potential to yield excellent outcomes, but it remains technically challenging.[4]

Indications

Indications for the various techniques employed in fingertip amputation vary, as follows. (See Technique.)

If the fingertip injury is less than 1 cm2 or is in a child with adequate soft-tissue cover over the bone, it can be managed nonoperatively with secondary healing.

Larger fingertip injuries that cannot be managed nonoperatively with healing by secondary intention alone—that is, those with a thin layer of epithelium that is not durable—can be treated with skin grafts taken from the hairless ulnar side of the hand.

With regard to reamputation, if the bone is protruding, the bone can be shortened and primary closure performed, or the wound can be left open for healing by secondary intention with granulation tissue. This approach is appropriate in adults with injuries that have less than 5 mm of sterile nail matrix present. It is also relatively indicated in patients with significant systemic conditions, for whom regional flaps are contraindicated and techniques such as skin graft or open technique are not possible.

A V-Y flap is indicated if the angle of fingertip amputation is either oblique with more tissue loss dorsally or transverse. It can be performed only if significant palmar tissue is available for dorsal advancement.

Volar flap advancement was previously used for all fingers; currently, it is recommended only for thumb fingertip amputation where less than 1.5 cm of advancement is required for coverage. In other fingers, the venous drainage depends on the volar flap, and this technique thus increases the risk of necrosis of the entire flap.

A bipedicle dorsal flap is indicated only for cases in which the fingertip amputation is proximal to the nail bed and in which preserving all its remaining length is essential but attaching to another finger is not desirable.

A crossfinger flap is indicated when local flaps are not possible and maintaining the remaining length is essential. It is especially useful in multiple-digit injury, where maintenance of length in the remaining injured fingertips is considered essential.

A thenar flap is indicated in any fingertip amputation with exposed bone.

Contraindications

Contraindications for the various techniques employed in fingertip amputation vary, as follows. (See Technique.)

Open technique is contraindicated in any fingertip amputation with exposed bone. It is relatively contraindicated in injuries in adults that include tissue loss of more than 1 cm2.

Skin graft alone is insufficient in fingertip amputation with exposed bone.

Reamputation is relatively contraindicated in cases where maintaining remaining length is essential. Otherwise, this procedure can be performed in most cases, though it is not always advantageous, because length is lost.

A V-Y flap is contraindicated when the geometry of the fingertip amputation is oblique with more tissue loss on the volar side. Furthermore, this procedure is not possible with more proximal fingertip amputations.

Volar flap advancement is relatively contraindicated in fingers other than the thumb, in that it may result in necrosis of the whole flap. Also, if the defect is more than 2 cm, this technique should not be used.

A bipedicle dorsal flap is not possible when the fingertip amputation is very distal and in cases where the soft tissue loss is significantly at the sides.

A crossfinger flap is avoided in patients older than 50 years and in hands with arthritis or a tendency toward finger stiffness. It is also avoided if local infection is present.

Any tendency toward finger stiffness is a relative contraindication for a thenar flap.

Technical Considerations

Anatomy

The basic skeleton of the wrist and hand comprises a total of 27 bones. The hand is innervated by three nerves (median, ulnar, and radial), each of which has sensory and motor components. The muscles of the hand are divided into intrinsic and extrinsic groups.

The hand contains 14 phalanges. Each digit contains three phalanges (proximal, middle, and distal), except for the thumb, which only has two phalanges. To avoid confusion, each digit is referred to by its name (thumb, index, long, ring, and small) rather than by number.

The nails are specialized skin appendages derived from the epidermis. The nail bed has a germinal matrix, sterile matrix, and hyponychium. ABout 90% of the nail plate is produced by the germinal matrix, which approximately corresponds to the lunula (the pale semicircle in the proximal nail bed). This germinal matrix starts proximally at the base of the distal phalanx just distal to the insertion of the extensor tendon.

The entire nail matrix is in intimate contact with the periosteum of the distal phalanx; therefore, it is vulnerable to injury when the latter is fractured.

For more information about the relevant anatomy, see Hand Anatomy.

Outcomes

Arsalan-Werner et al retrospectively analyzed a cohort of 28 patients with traumatic fingertip amputation (29 fingers) of Allen type III/IV injuries who underwent reconstruction with a neurovascular island flap in order to examine the long-term clinical outcome of of this approach.[5] No mandatory splinting was applied postoperatively. Patients were followed for a mean of 8 years after reconstruction.

The study documented no intraoperative complications, and all flaps survived.[5] Active motion of the fingers was over 95% of the contralateral side at follow-up. The grip strength of the affected hand and of each of the affected fingers exceeded 70% of the contralateral side. No significant difference was detected between the two sides on the Semmes-Weinstein monofilament test, but two-point discrimination was significantly impaired on the affected side. The Disabilities of the Arm, Shoulder, and Hand (DASH) score was 16.0. All patients returned to their original occupation, and there was a high level of patient satisfaction with the procedure.

In a retrospective study that included 37 patients with Tamai zone 1 fingertip amputation of the index or middle finger, Nakanishi et al compared the clinical results of two surgical procedures for fingertip amputation: reconstruction with a digital artery flap (n = 23) and microsurgical replantation (n = 14).[6] At a mean follow-up of 34 months, there were no significant differences between groups with regard to the primary outcomes (hand dexterity and disability of the upper extremity), but the secondary outcomes (strength, digital sensitivity, and finger mobility) were significantly better in the reconstruction group.

In a study evaluating the long-term (>10 y) outcomes of 34 successful fingertip replantations in 31 patients, Hayashi et al reported the following[7] :

No chronic pain
No cold intolerance in 32 digits
Recovery of protective sensation on Semmes-Weinstein monofilament testing in 27 digits
Excellent or good recovery on the moving two-point discrimination test in 91% of patients
Satisfactory sensory recovery, regardless of nerve repair or injury type
Moderate-to-severe nail deformity in six digits
Replanted fingertip volume 82 ± 17% that of the contralateral normal digit
Patient satisfaction rate of 97%

Periprocedural Care

Preprocedural Planning

Because functional requirements differ from one individual to the next, management options must always be discussed with the patient.

Management starts with a history elicited from the patient regarding the nature of the injury, age, hand dominance, occupation, recreational activities (including playing sports and musical instruments), previous history of hand injuries or problems, and other systemic diseases that affect wound healing.

A complete hand examination should be performed, estimating the amount of injury to the fingertip, angles and levels of amputation, loss of tissue, involvement of nail, involvement of other fingers, neurovascular involvement, and function of the hand. Investigations include radiographs of the affected finger to reveal whether the injury is associated with any underlying fractures or foreign bodies; fractures may require further treatment.

After assessment of the fingertip injury, a treatment plan should be formulated. If more than one option is available, the potential benefits and risks of each option should be discussed with the patient before the final treatment is selected.

Equipment

The choice of surgical instruments is left to the surgeon. In general, a basic surgical tray is all that is needed. Possible instruments include the following:

Hand surgery instruments - Scissors, retractors, needle holders, scalpel, forceps, clamps, elevators
Bone instruments (if bone end must be trimmed) - Drill and accessories, osteotomes, mallet, retractors, curettes
Tendon and nerve repair instruments - Tendon strippers
Irrigation supplies (for wound cleaning)

Patient Preparation

Anesthesia

Fingertip amputations can be performed with general anesthesia or regional anesthesia. Regional anesthesia is generally preferred, and many simple procedures can be performed with digital blocks. If multiple fingers are involved because of the injury, or proximal tissues are involved either as a flap or skin graft, then a Bier block or general anesthesia may be used.

Preferred anesthesia for each procedure is as follows:

Open technique - Digital block for pain control, including during cleaning and dressing
Skin graft - Wrist block, Bier block, general anesthesia
Reamputation - Digital block
V-Y flap - Digital block
Volar flap advancement - Bier block, general anesthesia
Bipedicle dorsal flap - Bier block, general anesthesia
Crossfinger flap - Wrist block, Bier block, general anesthesia
Thenar flap - Wrist block, Bier block, general anesthesia

Digital nerve blocks can be performed via either a volar or a dorsal approach. The author prefers to use the dorsal approach because the volar approach usually results in incomplete dorsal anesthesia. Because of this, more anesthetic may be required to be administered locally or dorsally to numb the dorsal digital nerves. For more information, see Digital Nerve Block.

The volar approach includes the following steps:

Prepare the area with antiseptic solution
Pass the needle over the flexor sheath at the level of metacarpophalangeal (MCP) joint, then direct the injection on either side of the flexor tendon

The dorsal approach includes the following steps:

Clean the web spaces at the base of the finger with antiseptic solution (preferably chlorhexidine)
Insert needle into the dorsal skin, brushing aside the head of the metacarpal
Before inserting deep, create a wheal dorsally by injecting local anesthetic into the dorsal skin, blocking the dorsal digital nerves
Then direct the needle volarly and block the digital nerves by injecting additional local anesthetic

With such an injection, widening of the webspace may be seen. Repeat the same procedure on the other side of the metacarpal.

Positioning

Position the patient supine on the operating table with the affected arm supported over an arm board.

For procedures involving areas proximal to the MCP joint, an arm tourniquet is used. For procedures not involving areas proximal to the MCP joint, a digital tourniquet can be used. A digital tourniquet can be made at the operating table with an elastic glove, as follows:

Cut off a finger of a glove; cut the tip off as well, so that it looks like a cylindrical tube with openings at both ends
Insert the tube on the finger, starting distally and gently rolling down proximally until it reaches the base of the finger; this process of rolling the tube down the finger acts to exsanguinate the finger
When the base is reached, a small curved artery forceps is used to hold the rolled tube and then rotated to act as a tourniquet

Technique

Approach Considerations

With most fingertip injuries, the choice of technique depends on the geometry of the fingertip injury (see the image below) and, to a certain extent, the expertise of the surgeon. The loss of tissue at the fingertip may be transverse or oblique, with more tissue loss on the volar side or on the dorsal side. Some amputations may take more tissue from one side or the other (ie, the radial or the ulnar side).

Geometry of fingertip amputations.

The main techniques currently available for repairing fingertip amputations are as follows:

Open technique (nonoperative; healing by secondary intention)
Skin graft
Reamputation
V-Y flap (Kutler or Atasoy)
Volar flap advancement (Moberg) ^[3]
Bipedicle dorsal flap
Crossfinger flap
Thenar flap

Each of these techniques is discussed separately below. Surgical preferences vary substantially.[8, 9]

Additional techniques have been described, including the palmar pivot flap for lateral defects in the fingertip injuries,[10] the reverse midpalmar island flap for complex reconstruction of fingertip amputations,[11] and the fenestrated adipofascial reverse (FAR) flap.[12] However, these techniques are not yet as commonly used as those listed above.

Fingertip replantation has become an established technique with the potential to yield excellent outcomes, but it remains technically challenging.[4] and has not been as commonly performed in the United States as it has elsewhere in the world.[1]

Options for Amputated Fingertip

Open technique

This is nonoperative management of fingertip amputation in which the loss of skin or pulp is less than 1 cm2, which can heal by secondary intention.

The wound requires cleaning and dressing at regular intervals. Advise the patient to begin 1 week after the procedure to soak the finger in a warm water-peroxide solution daily and then apply the dressings with a fingertip protector.

In selected cases, where the tip of the bone is exposed, it can be trimmed with bone cutters to the level of the soft tissues and then allowed to heal by secondary intention. However, better results are usually achieved in such cases if an additional procedure is performed.

Complete healing takes place in 3-6 weeks.

Skin graft

Larger wounds allowed to heal by secondary intention may result in a thin, nondurable layer of epithelium. In such cases, skin grafting from the palmar surface is preferred, and these are generally taken as full-thickness skin grafts.

The preferred donor site is the hypothenar area of the palm. The full-thickness skin graft taken from this site is durable and is an excellent cosmetic match to the pulp of the finger. Also, this donor site is convenient from the surgeon's perspective.

When the full-thickness graft is taken, the underlying fat should be completely removed before application.

The other areas from which a full-thickness graft can be procured are the medial aspect of the arm distal to the axilla, the volar side of the forearm and wrist, and the amputated part of the fingertip, if it is available. The latter can be performed more successfully in children than in adults.

Split-thickness grafts can also be performed; however, full-thickness grafts are preferable for their durability. Also, split-thickness grafts contract with time while healing.

Reamputation

Shortening and primary suturing can be done in certain cases.

When shortening is contemplated for fingertip injuries, remove the remaining germinal matrix of the nail to prevent future problems from the nail remnant. To do this, make incisions on either side of the nail wall and reflect the nail wall proximally, extending from the eponychium. If shortening leaves the patient with a stump of distal phalanx, carry out disarticulation at the level of the distal interphalangeal (DIP) joint.

Remove the prominent volar condyles of the middle phalanx with a bone cutter or a rongeur. Pull the flexor and extensor tendons distally and transect them, then allow them to retract. Excise the palmar plate and the collateral ligaments to avoid bulking of the tip and give a better contour to the tip. To avoid painful neuromas, identify the digital nerves and dissect them proximally, then pull and transect them 1 cm proximally from the skin edge (tip).

If the plane of the amputation is transverse, bring the palmar skin forward to suture with the dorsal skin. If a long flap of skin is available, as in cases where the plane of the injury is oblique, use the excess skin to cover the tip as a flap. Suture the skin without any dog ears.

V-Y flap

After trimming the bone ends, in cases of distal transverse fingertip amputations, create a V-Y flap with a triangular flap that has the wound edge as its base. The apex should be the midpoint of the DIP joint. Only the full thickness of the skin is cut. (See the image below.)

V-Y flap.

Adequately mobilize this flap by passing a No. 15 blade tangentially on the volar aspect of the bone from the distal edge of the wound. Use the knife blade to divide all the fibrous septa anchoring the pulp to the underlying bone. Once the flap is completely mobilized, pull it over the fingertip and suture it to the nail bed dorsally.

At this juncture, release the tourniquet to assess the capillary refilling of the flap. A pale flap indicates that the flap is not adequately mobilized and that the vessels are stretched. In this case, remobilize the flap, taking care to divide all the fibrous septa anchoring the pulp to the underlying distal phalanx.

Once satisfactory capillary refilling is present in the mobilized flap, close the rest of the wound with V-Y plasty without any tension.

A dorsal V-Y flap is described in the literature, used for volar oblique fingertip amputations with more volar soft-tissue loss.[13] A double V-Y flap technique has been described for cases where a simple V-Y flap does not provide sufficient coverage.[14]

Volar flap advancement

A volar flap is normally used for injuries to the tip of the thumb. (See the image below.)

Moberg flap.

After the debridement of the fingertip, make midlateral incisions dorsal to the neurovascular bundles, and dissect the flap from the flexor tendon sheath. Mobilize the flap and advance it along with the neurovascular bundles. The advancement is helped by flexion of the interphalangeal (IP) joint of the thumb. If the flap is under tension, perform a transverse incision on the skin at the base of the flap. This results in a rectangular defect that needs a full-thickness skin graft.

In the other fingers, the prospect of flap survival is increased by limiting the volar flap incisions distal to the proximal interphalangeal (PIP) joint.

Bipedicle dorsal flap

Start the incision at the proximal margin of the fingertip defect, and proceed proximally on the dorsum of the finger to elevate skin and subcutaneous tissue. At a more proximal level, make a transverse dorsal incision to create a bipedicle graft to cover the defect at the fingertip.

The flap can be made more mobile by dividing one of the pedicles; however, this comes with the price of increased chance of necrosis of the flap. Use a full-thickness skin graft from the volar aspect of the distal forearm to cover the defect created by taking the flap.

Crossfinger pedicle flap

The crossfinger pedicle flap technique calls for proper planning, templating, and forming of a pattern before the flap is actually created. The technique also depends on the size and location of the defect and the other finger injuries.

The flap can be based either proximally or distally. More commonly, the flap is taken from the neighboring ulnar finger with the base laterally. The flap is taken from the dorsal aspect. Keep the template 2 mm larger than the required size so that the final suturing can be done without tension.

Dissect the flap down to the plane between the subcutaneous fat and the paratenon of the extensor tendon. Check the vascularity of the flap, and then apply it over the defect in the adjacent fingertip. Fill the defect in the donor area with a full-thickness skin graft taken from the groin.

To minimize the chance of crossfinger pedicle flap failure, transfix the middle phalanges of the two fingers with K-wires. This prevents excessive tension and torsion of the flap.

When the procedure is complete, apply a large bulky dressing. Detach the pedicle 2 weeks after the initial procedure. Gradually attempt mobilization for the fingers to avoid finger stiffness.

Thenar flap

With the thumb in abduction, flex the injured finger so that the tip touches the thenar eminence.[15] (See the image below.)

Thenar flap.

Mark the margins of the flap so that enough tissue is available to suture without tension. Design the flap with the base proximally. The length of the flap should not be more than twice the width of the flap.

Raise the flap with as much of the underlying subcutaneous fat and suture it to the fingertip without tension. Close the defect in the donor area primarily; a graft is not needed. The flap should not have any buckling or kinking that may interfere with the vascularity.

Apply a large bulky dressing. After 48 hours, change to light dressing with the flap partially exposed. After 2 weeks, detach the pedicle.

Considerations in pediatric patients

Amputations through the eponychium may be replanted with variable success. Revision amputation is usually performed at the level of the eponychium. If at least 25% of the nail bed is present, the patient benefits from maintaining that nail. However, resection is recommended if less than 25% of the nail bed is present.

In children, the tip of the finger is often avulsed with the nail bed. In such cases, approximations are made of the edge of the nail bed and skin tip as a composite graft. To hold the bone in place, longitudinal or crossed pins are used. The younger the child, the better adherence of composite graft of skin and nail bed are seen. The greatest success rates are seen in children aged 3 years or younger. However, in an older child, a cap graft is likely to hold greater success.

Complications

Postoperative complications can be broadly divided into problems at the site of nail growth (sterile matrix) and problems at the site of nail support (distal phalanx), as follows.

Sterile matrix problems - A scar within the sterile matrix can result in various deformities, such as notching, nonadherence, splitting, and elevation of the nail; such problems prevent growth or adherence to the nail bed scar
Distal phalanx problems - Excessive debridement can lead to an uneven dorsal cortex and loss of bony support, resulting in nonunion of the distal phalanx or osteomyelitis

Early postoperative complications of an amputated stump include wound hematoma, infection, and necrosis. To minimize the risk of infection, irrigation and debridement of the amputation wounds are required. Antibiotic prophylaxis does not appear to decrease the incidence of infection.[16] Hemostatic control of the amputation stump can be achieved initially with a tourniquet.

If subungual hematoma or seroma is present 5-7 days after surgery, reopen the nail trephination hole or gently raise the nail at the paronychia to permit drainage. The suture used to hold the nail in place should be removed 5-7 days after the injury to prevent a sinus tract formation through the nail fold. In simple subungual hematoma, regardless of size, nail removal with suture repair of the nail bed is unnecessary. For more information, see Hand, Subungual Hematoma Drainage.

Particular techniques are predisposed to particular complications, as described below.