What is a replantation? Replantation of an amputated limb
What is a replantation?
Replantation is the process of surgically reattaching body parts that have completely lost their connection to the body (hands, fingers, etc.). The first successful replantation was performed in 1962 by Malth and Me. Khan, on the upper part of humerus of a twelve-year-old patient. In 1963, Chen performed a distal forearm replantation surgery.
The goals of the replantation surgery are:
- Restoration of blood supply to the amputated part
- Rational restoration of the amputated limb
- Restoration of motor and sensory characteristics of the limb
- Restoration of human operability
The goal of a replantation operation is to return the amputated limb to its original appearance, location and restoration of functional activity.
Amputations fall into two categories:
- Complete amputation
- Partial amputation.
A full amputation is the removal of all structures (including bone), but with a partial amputation, if the distal part of the limb is sufficiently supplied with blood, blood vessels do not need to be reattached. However, if the blood supply to the limb in a partial amputation is insufficient, it is necessary to reattach the vessels (revascularization).
Avulsion injuries belong to another category, because they cause severe damage to vessels and nerve roots. In such amputations, vessels and nerve roots of varying lengths can be seen in the area of the injury. The “ring sign” line allows you to confirm that the injury occurred over the vascular wall. With such amputations, the prognosis is unfavorable.
When performing an amputation on a partially injured limb, you must clean the injured area, apply a sterile dressing, set the fracture and apply a residual limb. No pieces of tissue should be torn off between the upper part of the incision and the lower part of the incision. During a complete amputation, to increase the time of cold ischemia, a sterile dressing is applied to the amputated limb and placed in a sterile glove that is sealed tightly. The glove is then placed in water filled with ice cubes.
A sterile dressing should be applied to the residual limb. A tight elastic bandage should be applied to the proximal part of the limb to stop bleeding.
The following is the sequence of operations when performing a reattachment:
- Shortening the bone (if necessary) and fixing it
- Restoration of the arteries (anastomosis)
- Vein reconstruction (anastomosis)
- Flexor and extensor tendon repair
- Nerve repair
- Skin stitching
Sometimes the amputated part cannot be sewn back into place. In these cases the torn limb is temporarily sewn into the abdomen or another limb. After three weeks of temporary replanting, the part is removed and sewn back into its proper place.
Dynamic observation of the limb after surgery for replantation is carried out.
- Check the color change of the limb
- Every hour assess the rate of capillary blood flow recovery
- Blood flow in the arteries is checked with Doppler test
Despite the perfection of the microsurgical technique, the main cause of failure is thrombus formation in the lumen of the vascular anastomosis. It is believed that 90% of arterial thrombosis, which occurs due to platelet aggregation, forms within the first day after surgery. 42% of venous thrombosis results from the deposition of fibrin threads, one day after surgery. Arterial and venous thrombosis occurs within the first three days after surgery. The risk of microsurgical failure is reduced to 10% three days after surgery. The picture of arterial thrombosis is characterized by pale skin, decreased tissue turgor and slow capillary filling, while in venous thrombosis the tissue becomes cyanotic.
In venous insufficiency, a light incision, a bandage with heparin and drainage with leeches are used first, but if these methods are not effective, a revision of the venous anastomosis is performed. The risk of thrombosis is minimized by preoperative anticoagulant treatment. These drugs include: aspirin, heparin, low molecular weight heparin, dextran. Paracetamol, opioids and etc. are used for pain relief. To prevent infectious complications, broad-spectrum antibiotics are used, which are administered intravenously.
Complications after amputation
These are divided into early and late complications:
Early complications: occur within the first three days after surgery:
- Adhesion (fusion) of the joints
- Non-union of bones
- Neurinoma formation, recurrent pain, hypersensitivity, unsteadiness to cold
- Visual deformity of the limb
- Shortening of the length of the fingers
- Loss of sensation, increased sensitivity, numbness
- Soft tissue atrophy
- Loss of nails, nail deformity
- Stiffness of movements
- Decreased ability to squeeze the palm
Contraindications to replantation
General absolute contraindications
- Life-threatening injuries
- Systemic disease – the patient is unable to withstand a lengthy operation
Local absolute contraindications
- Ischemia lasting more than 6 hours with amputation of the upper extremity proximal to the mid-limb
- Severe compression or tearing injury
- Ring avulsion
- Excessive wound contamination
- Improper storage of the amputated part
- Shoulder amputation
General relative contraindications
- Vascular disease, diabetes mellitus, arterial hypertension
- Older patient
- Mentally disturbed patients and those who can harm themselves
Local relative contraindications
- Lesions in several localizations
- Two cuts in one finger area (the thumb is an exception)
- Prolonged ischemia
After replantation surgery, certain factors can affect the outcome of the surgery after a short or long period of time. These include:
- The type and localization of the injury
- Duration of ischemia
- Diabetes mellitus
- Alcohol use
- – Smoking