The Case of the Lost Fingertip

A 36-year-old woman presents to a hospital wound care department in Japan, sometime after an accident where she lost the tip of her right third finger -- the finger was crushed in a thick iron door during her shift at a restaurant, and the amputated part was not able to be recovered.

She notes that when the injury occurred, she had first visited the emergency department of another general hospital, but the plastic surgeon there recommended surgical reconstruction, and the patient decided to opt instead for conservative management.

The patient was a smoker, with an unremarkable medical history.

Initial examination of the injury revealed loss of the nail plate, damage to the nail bed, and exposure of the distal phalanx; clinicians thus identified the injury as an Allen type III amputation. As per protocol for conservative management, the medical team applies moist wound dressings -- in this case, made of polyethylene, polypropylene, and cellulose.

The patient is instructed to wash the wound lightly with warm water in the shower once a day and apply a new dressing; management does not involve disinfectants or prophylactic antibiotics. The patient is instructed to return for a follow-up visit once every 1-2 weeks.

One week later, she is able to perform activities of daily living with only a few limitations due to mild pain at the fingertip when it is touched. She is advised to continue performing normal finger movements as long as they do not cause intolerable pain.

She is also told that while undergoing treatment she can return to work whenever she is ready. However, her return to work is significantly delayed as a result of prolonged discussions between the workplace and the patient regarding workers' compensation, the nature of her future work, and job changes.

Two weeks later, a new nail plate is beginning to grow, and the fingertip is covered with granulation tissue. At 4 weeks, growth of the granulation tissue is evident, and the fingertip is regenerating into the original fingertip shape.

At 8 weeks, the skin is almost completely regrown, with only a slight granulation remaining at the fingertip. At 12 weeks, epithelialization is complete, and clinicians reduce the frequency of follow-up. The patient has no local or systemic infections during the overall treatment period.

At 16 weeks, she reports numbness at the fingertip. At 27 weeks, she notes mild cold intolerance as well as persistent numbness, both of which improve over time. She is prescribed pregabalin 150 mg/day, mecobalamin 1,500 μg/day, and loxoprofen sodium hydrate 180 mg/day to be taken separately or simultaneously as needed to control the pain and numbness.

For about 6 months after the injury, she reports that on occasion she has pain or numbness that make it difficult to hold a pen or use chopsticks, but she gradually regains normal functional ability of her right hand.

At 39 weeks, she returns to work and notes being satisfied overall with the outcome.

Discussion

Clinicians reporting this case of an Allen type III fingertip amputation injury managed conservatively with moist wound dressings after the patient declined reconstructive surgery that had been initially recommended by a plastic surgeon note that she had excellent aesthetic and functional results by 12 weeks.

Fingertip amputation injuries are commonly encountered in emergency departments, with injuries to the wrist, hand, and fingers accounting for about 15% of such visits in the U.S. in 2017.

Fingertip amputation classifications proposed by M.J. Allen range from type I to type IV depending on the extent of the injury. While surgical management is used for most Allen type III/IV fingertip amputations, conservative management can also be a viable treatment option, as this case demonstrates.

Management strategies depend on the site and degree of tissue loss in the wounds, but preferred approaches also vary by country and region. For example, in the U.S., conservative management or revision amputation is the most common approach, with replantation performed in only about 14% of fingertip amputation injuries.

In contrast, the case authors note, Asian countries tend to use replantation or reconstruction more often, with the latter accounting for about 29% of fingertip amputation injuries in Japan. Data regarding the appropriate indications for replantation are scarce, but the approach is often used for distal fingertip amputations without bone defects, posing a challenge due to unresolved questions regarding cost and functional outcomes.

The authors suggest several explanations for the various preferences, including cultural differences such as moral values and the significance of body integrity, as well as the healthcare system involved and differences in insurance reimbursement.

These factors may help account for potentially excessive use of operative management strategies for fingertip amputations in Japan, although recent years have seen growing public acceptance of conservative management using moist wound dressings, the case authors note.

Moist wound dressings are commonly used in conservative management; options include self-adhesive elastic bandages with a moistening agent, and film dressings. In this case, clinicians used a multi-layered non-adherent wound dressing able to self-regulate the absorption of the exudate and that is available in drugstores or online stores; the wound is covered, and the dressing is replaced once a day.

With no established recommendation for the most suitable wound dressing for fingertip amputations, individual hospitals need to consider what is appropriate and accessible for their facility, the case authors advise.

Healing time depends on the degree of injury: revision amputation may heal more quickly than other management methods, although conservative management has a reported average healing time of 2-12 weeks. Patients with exposed bone take the longest to heal; in this case, the size of the defect and exposed bone -- as well as the patient's history of smoking -- may explain the relatively long healing time of 12 weeks.

Given that, amputation may be preferred for similar patients who cannot tolerate an open wound for a long time and desire faster healing; in such cases, the reported average time to return to work is 1.5 months after revision amputation and 3.2-4.0 months after replantation, the case authors note.

In contrast, patients treated with conservative management can often return to work within the first week, and most patients return after an average of a month, although return to food service jobs may take longer.

When a fingertip amputation involves an exposed bone, surgical bone-shortening is recommended before conservative treatment to facilitate healing, although in this case, the authors note, other research suggests not bone-shortening unless the protruding bone has sharp bone spicules, to avoid causing a hook nail deformity due to loss of bony support in the fingertip.

Conservative treatment is associated with regeneration of the soft-tissue thickness of the fingertip of up to 85% in the palmar direction and 93% in the distal direction, which reflects the outcome in this case: "Interestingly, as the granulation tissue gradually grew, the fingertip regenerated into a natural finger shape 4 weeks after the injury ... and the nail bed regenerated almost normally, showing excellent aesthetic results," showing that surgical repair to the nail bed is not always essential, the case authors wrote.

Cold intolerance is commonly associated with conservative treatment, although evidence suggests that it gradually improves and resolves by 1 year and is commonly reported after operative treatment, especially in revision amputation. This complication is assumed to be due to vascular insufficiency and peripheral nerve injury related to the injury, regardless of the treatment method, the case authors explain.

Changes in sensitivity are fairly rare, but are more common in proximal injuries, and can leave patients who received conservative treatment unhappy with the outcome. This patient's cold intolerance and numbness interfered with her normal activities of daily living, but both resolved over time, which shows the importance of preparing patients for possible initial sensory abnormalities that frequently improve over time.

Each possible treatment has advantages and disadvantages, the authors continue. For example, revision amputation provides faster healing but does not restore the original finger length and is often associated with cold intolerance, while replantation can help restore the original finger, given a sharp amputation mechanism, proper retrieval of the amputated digit, and availability of immediate replantation. Replantation also involves long-term rehabilitation and a potential for persistent finger stiffness.

Reconstruction using local flaps has the advantage of being able to handle various types of fingertip amputations and preserve the finger length, although this approach also requires prolonged immobilization and risks flap failure.

Conclusion

The case authors conclude that conservative management with moist wound dressings for fingertip amputation injury is simple, with overall treatment outcomes that are satisfactory for patients. Conservative management may therefore be a preferable strategy for fingertip amputation injuries, depending on the nature and degree of the injury. It should be noted, however, the authors state, that because conservative management requires a longer healing time, the nature of the patient's work and the expected recovery time should be taken into account when considering management strategies.

Comment