Dr Patrick HOUVET/F.I.H.S

Since the first hand reimplantation -which had been completely amputated- successfully performed by Dr. Chen in Shangai, in January 1963, the domain of hand and finger reimplantation has developed considerably due to the advances in microsurgery. The possibility of suturing vessels and nerves through microsurgical techniques has become broadly popular in the media.

In addition to this outstanding aspect, a hand or finger reimplantation is only legitimate if the body part has good chances of accomplishing a good functional result for the individual.

                 

General guidelines :

Wrapping :
Do not loose time. The amputated part should be cleansed by running water, then placed in double dressing, which is put on a tight plastic bag. This bag is put in a container with ice -around 4 degrees- in order to protect devascularised tissues. Do not place the amputated body part in direct contact with ice.

Homeostasis :
Place a pressure dressing in order to stop haemorrhage. Tourniquets are not useful, and ligature control of vessels is incorrect.

Ischemia:
The time elapsed before the appearance of ischemia of the amputated part is one of the key factors to achieve a good procedure and proper functional recovery in the long term. It is preferable to perform a reimplantation within 4 hours of a "warm" ischemia, that is, room temperature; and if it is a "cold" ischemia, within 6 hours.

The tolerance of fingers is better than that of a larger part, due to the absence of muscular tissue. Successful cases have been also reported within more than 90 hours delay

What does a surgical intervention involve ?

First, assessment of the feasibility of reimplantation.
The patient's history aims at collecting data that will be used for prognosis and susceptible elements for the surgical procedure : the cause -clean cut, crush, avulsion, bruise, etc. -duration of the tissue ischemia, vascular situation, eventual use of tobacco and smoking products, profession and leisure activities.

the local examination estimates the level of amputation and the degree of bruise. The general examination finds a state of shock due to the great loss of blood.

Surgical preparation of the amputated part and the amputated limb : the body parts to be repaired will be located by means of magnification. This allows to gain time to perform the following procedure ; it also allows to keep the tourniquet for a longer time to later perform the actual procedure. The amputated part is cleansed and the damaged tissues are removed. This is the moment in which the more suitable technique for vascular reparation is selected : direct suture or bypass.

Reparation : it is a long procedure (2-6 hours), and involves the successive reparation of all body parts. It is started with a bony stabilisation. The fracture is stabilised through pins or screws. Later, the most delicate structures of the finger will be repaired. The tendons are useful to provide motion. All tendons are repaired with suture, which puts the tendon ends in contact back again, until tendon fixation is achieved. Therefore, the reparation will remain fragile for at least 3 weeks.
Nerves are involved in the sensory function. They are repaired under microscope, since their diameter -at the level of the fingers- is of 1-2 millimetres. In fact, the procedure involves the nerve sheaths. After that, the nerve heals inside its sheath at a speed of 1mm per day.

Vascular reparation is the most important procedure for the survivorship of the finger. In order for the blood to circulate, it is necessary to have at least one artery and one vein. The more distal the location of the injury, the smaller the vessels; the radial artery at the level of the hand is 2mm long, the collateral artery at the base of the finger is 1mm, and the arteries of the last phalanx is 0,3 to 0,5 mm long.
Vessels are repaired under microscope with micro needles and micro sutures: 70- to 100 microns -one thousandth of a millimetre-.
If no veins could be repaired (reimplantation of the fingertip), continuous bleeding should be initiated to prevent the tissues from obstruction. The uses of leeches may sometimes be helpful in this case.

Observation after surgery


During the first 8 days, survivorship of the reimplanted finger depends on the blood circulation and therefore of the permeability of the small vessels which have been repaired.
These vessels are very fragile and certain essential precautions should be considered.

Discontinue the use of tobacco. Just one cigarette may cause arterial spasm and involve the survivorship of the finger.

Keep the finger in a warm place.

a continuous anticoagulant treatment, by means of an electric syringe which will limit displacement, but as the flow of blood increases, it prevents further complications.
The blood supply should be observed each hour; the elements for observation are fairly simple, you can perform the observation yourself.

The finger should be : pink, warm, and it should become red after applying pressure on it (capillary pulse)

Modification of colour (white or blue), local temperature (cold), or capillary pulse (slow or fast re-colouration), may lead to venous or arterial complications. In some cases a new reparation is possible.
Time should not be long before observation is started; so, you may have a nurse observe your finger each hour, even at night.

After about 6 days, skin scarring may allow to regain venous flow and bleeding may stop without running risks.
After 8 days, this observation is no longer required, providing the finger has good blood supply, since the critical period has already passed. Then, rehabilitation starts

Functional recovery

Functional recovery of a finger requires several months of efforts through rehabilitation. Fracture fixations usually occur in 1-2 months. Sensory function is regained in 3-6 months. Motion requires precise and regular rehabilitation. During the first 3 weeks, you should not move your finger, since the tendons are still delicate. The physical therapist will be the one to "passively" move your finger in flexion. After the third week, you will be allowed to actively move your finger, and gradually increasing degree of motion.
The aim of rehabilitation is motion recovery. Strength, which depends upon the muscles in the forearm, not the finger, will be later recovered with the use of your hand

Results

The survivorship rate of reimplanted fingers varies in accordance with the level of amputation, type of injury, quality of wrapping of the amputated body part during transport. The rate is around 90% (clean cuts at the base of the finger), and less than 50% (avulsion of fingertips). Reimplantations of the tip provides the finger with near normal aspect.

Functional results are variable. The closest the injury to the base of the finger, the hardest it is to avoid stiffness, which is the result despite rehabilitation. A stiff and painful finger can disturb the whole hand; therefore, it is sometimes preferable not to reimplant a finger, if it is previously known that it will cause discomfort, despite the technical feasibility of the reimplantation.