A severed finger, or amputation injury of a finger, is a severe and certainly dramatic incident. The most important steps one can do to aid the treatment of such an injury and improve the success of re-attachment are:
1. Recover the amputated part.
2. Wrap the amputated part in a clean, moistened cloth or towel – Do NOT soak or immerse in any fluid.
3. Place the cloth or towel containing the amputated part in a clean and dry plastic bag.
4. Place this plastic bag in another bag filled with ice. This will keep the amputated part cool.
The amputated part should be kept moist and cool in this manner and care should be taken not to allow it to be in direct contact with the ice as this can then cause frostbite damage to the amputate, rendering it unsalvageable. In preparation for emergency surgery, the patient should be kept fasted and not be given any food or water until further advice by a doctor.
The patient and the amputated part should be rushed to an Accident & Emergency department of any hospital and request for an urgent referral to a Hand Surgeon. After the relevant clinical assessments are performed, including X-rays of the injured digit and amputate, the Hand Surgeon will then schedule an emergency operation to re-attach the severed finger. This operation is known as Replantation.
The technical steps of replantation surgery are complex and require the handling and skills of a hand surgeon trained in microsurgery. Depending on the level of the amputation (distal, meaning closer to the fingertip, or proximal, meaning closer to the hand) and the experience of the hand surgeon, replantation of a single digit may take 3-6 hours. The general outline of replantation surgery is as follows:
1. Thorough debridement (cleaning and refreshing of tissue) of both the amputated part and the finger stump of the patient. This will ensure that all contaminated and non-viable tissue is removed to avoid complications such as infection and tissue necrosis.
2. Shortening of the bone ends – This is a crucial step to ensure that the soft tissue can cover the bone. In some situations, a joint may have to be sacrificed due to the severity of the bone injury and this will lead to a fused joint.
3. Fixation of the bone with metal wires or plate and screws.
4. Extensor and flexor tendon repair with special suture techniques.
5. Microsurgical anastomosis (joining of the blood vessels) of the digital veins and arteries. This step determines the success or failure of the replantation as these vessels supply blood to the amputated finger.
6. Microsurgical repair of the digital nerves. This step restores the continuity of the nerves which give sensation to the fingertip.
7. Skin closure with or without skin grafts. Skin grafts may be necessary if direct skin closure is not possible without compromising the blood flow – tight skin closure may strangulate the blood vessels and increase the risk of failure.
After surgery, the patient will be kept in the general ward for microsurgical monitoring of the replanted finger for a minimum of 7 days. During this time, the fingertip is monitored for colour, capillary refill and surface temperature using a contactless thermometer. Any compromise in these parameters signal a possible occlusion in blood flow and may require immediate surgical exploration and revision of the vessel anastomoses.
After successful replantation, the patient is discharged and followed-up in the outpatient clinic. The sutures are removed at 2 weeks after surgery. Hand therapy is also commenced then to rehabilitate finger movement and function. Patients usually recover functional use of the hand within a year.
