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Replantation
5.8 Replantation Shilu Shrestha, James Chang
SYNOPSIS The term replantation is used when there is surgical reattachment of a completely amputated body part. In contrast, when there is some tissue still attached, and reattachment of this incompletely amputated part requires microsurgical repair of the vessels, this is called revascularization. Malt and McKhann performed the first successful upper arm replantation in 1962,1 and Komatsu and Tamai reported the first successful replantation of a digit in 1968.2 Since then, microsurgery and replantation have been a basic part of training and routine practice for hand surgeons. Even the best available hand prosthesis has not been able to entirely replicate the function of the hand as effectively as prostheses for the lower extremities. Furthermore, cultural and religious practices in certain countries place a particular emphasis on the presence of all body parts upon death. Therefore replantation is becoming increasingly important in all countries, regardless of socioeconomic conditions. Although microsurgery has seen considerable advances in recent years, hand surgeons have been increasingly critical with regard to outcomes of replantation.3 It is vital to understand that the successful outcome of the replantation does not just depend on microsurgical repair of the vessels but also on restoration of bone, tendon, nerve, and skin. Tendon repair is likely to be the most important step for better long-term outcome of the replantation.
CLINICAL PROBLEM The need for a detailed history focuses on the health of the patient and the cause of the amputation. The key points to be considered are enumerated later, and a summary of the relative indications and contraindications is listed in Table 5.8.1.
Age Younger patients may have better outcomes with nerve and tendon repair. Children may have more technically demanding surgery because of the small caliber of the vessels.4 Older patients are more likely to have systemic diseases and atherosclerosis of the vessels.
Occupation The patient’s occupation and hobbies may help determine whether s/he requires gross or fine motor function of the hand. For example, a construction worker may be better served by a completion amputation and early return to work, whereas a pianist may wish all efforts at replantation to be made.
Associated Injuries If the amputation is associated with life-threatening major injuries, it may be wise not to perform replantation. The overall patient is more important than the digit.
Warm Ischemia Time This is more critical for major replantation in the hand and more proximally, where there is significant muscle that may become ischemic. Amputation proximal to the radio-carpal joint results in irreversible changes leading to myoglobinuria and renal failure if replanted beyond 6 hours of warm ischemia time. However, this time length is much longer in a finger, where there is very little muscle tissue.
Etiology and Mechanism of Injuries A detailed history of the mechanism of injury provides information to foreseeing the severity of injury and the likelihood of success. Sharp cut or guillotine amputations have clean margins and are best suitable for replantation, whereas crush and avulsion injuries may have tissue loss and multiple-level injuries. Wound contamination increases the risk of infection and requires radical debridement.
Associated Conditions Associated comorbidities such as diabetes, coronary artery disease, chronic obstructive pulmonary disease, history of smoking, drug dependence, and psychiatric illness are negative factors for replantation.
PRE-OPERATIVE MANAGEMENT Physical Examination Examining the patient as a whole is very important. There is a tendency to mistakenly exclude other pertinent signs that may lie outside our area of expertise. However, general examination should always precede the focused examination because it helps avoid the risk of missing the major injuries. In cases of trauma, a full body survey should be performed to rule out other injuries.
General Examination Determining the general health of the patient is critical for pre-operative decisions such as the specific procedure, required preparation, and type of anesthesia. In most cases of replantation, the patient should be healthy enough for a long time period of general anesthesia.
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SECTION 5 Hand Surgery
TABLE 5.8.1 Indications/Contraindications
for Replantation Indications
Contraindications
1. Pediatric amputation 2. Thumb 3. Multiple fingers 4. Patient desire
1. Major replantation with prolonged warm ischemia time 2. Associated with life-threatening injuries 3. Multiple-level amputation 4. Severe avulsion or crush 5. Severe contamination 6. Severe comorbid conditions 7. Severe psychiatric illness 8. Age >70 years
Regional Examination The whole limb should be examined so as not to miss proximal injuries.
Focused Examination Both the limb and the amputated part should be examined thoroughly. It is typically better to conduct the gross examination during the initial presentation of the patient in the emergency department, followed by a thorough, detailed evaluation in the operating room. This approach saves time and reduces the unnecessary hassles of insufficient lighting and supplies.
Factors Requiring Evaluation • • • •
Single-digit vs multiple-digit injury Level of amputation Clean cut vs crush/avulsion mechanism Amount of contamination
COUNSELING Patients and their relatives almost always desire the replantation of any part of their body. However, they are typically not aware of the required procedure in detail, its associated risks, the cost, and the potential complications and outcomes of the surgery. It is therefore the responsibility of the operating surgeon to discuss the proposed procedure in detail so as to facilitate the making of well-informed decisions by the patient. The likelihood of completion amputation should be emphasized.
Topics to Be Discussed 1. Duration of surgery, post-operative therapy, and length of hospital stay. 2. Likelihood of success. 3. Possibility of multiple surgeries for re-exploration, re-revascularization, and secondary surgeries. 4. Possible need for blood transfusion. 5. Possible need for skin, vessel, and nerve grafts. 6. Intensive rehabilitation and time off from work, 7. Expected outcome in terms of function, appearance, and sensibility. 8. Cost. 9. Options of alternate surgeries and their outcomes, including completion amputation.
INVESTIGATIONS Routine tests should be performed to determine the general health of the patient, risks and complications of blood loss, and suitability for the procedure. Tests, depending on individual need, include:
1. Basic blood tests: a. Complete blood count b. Blood type and crossmatch for major replantations c. Renal function test if indicated 2. Radiograph a. x-ray of the proximal extremity and the amputated part should be taken b. Chest x-ray if indicated 3. Electrocardiogram if indicated
EMERGENCY MANAGEMENT AND PREPARATION The patient should be stabilized before being taken to surgery. 1. Analgesia Adequate analgesia should be given because excessive pain results in vasoconstriction. It also has the added benefit of reducing patient anxiety. 2. Tetanus prophylaxis This should be given if the booster dose has been given at least 5 years prior or if the immunization history is uncertain. 3. Antibiotics A first-generation cephalosporin usually suffices. Aminoglycoside and metronidazole can be administered if indicated, in cases of severe contamination. Penicillins should be administered in the case of farmyard injuries. 4. Blood and fluids Patients with amputations, especially above the radio-carpal joint, are at a high risk of losing significant amounts of blood at the amputation site. Blood transfusions may therefore be necessary. Patients should be well hydrated to reduce the likelihood of hyperviscosity. 5. Urinary catheter placement Replantation procedures are typically long in duration, and an indwelling catheter is therefore recommended. This has the added benefit of serving as a useful indicator of the patient’s hydration status intraoperatively and post-operatively. 6. Preparation of the amputated part The parts should be irrigated and wrapped with saline-soaked gauze. The part is then placed in a plastic bag, which is then placed in an ice bath. This allows cooling of the part while avoiding direct contact with ice or saline (Fig. 5.8.1). 7. Proximal extremity In such injuries, the patient is usually taken to the operating room immediately. Therefore simple irrigation and a moist dressing are usually sufficient. Control of bleeding should be achieved with pressure dressings rather than blind attempts at clamping or ligation, which is invariably inefficient and risks unnecessary vessel and nerve damage. 8. Team call A team approach is always preferred for expedited management and reduction of surgeon fatigue. This is particularly important in major replantation and in multiple-digit replantations. 9. Bench work Effective bench work reduces intraoperative time. While the patient is being stabilized in the emergency department and transferred, the operating surgeon can make effective use of this time to prepare the amputated part for the procedure even before the patient is brought into the operating room. Specifically, the amputated part is cleaned, evaluated thoroughly under the microscope, and debrided. Important structures are tagged for ease of identification later.
CHAPTER 5.8 Replantation Early care of amputated part
Amputated part
371
minimizes blood loss and ensures that the technically most demanding step is completed before the tourniquet is released. Conversely, performing the arterial anastomosis before the venous anastomosis allows identification and selection of the veins with good flow. The arterial repair is preferably done first in distal replantation procedures because it is easier to identify ideal veins after, and in major replantations it is part of an effort to decrease the warm ischemia time.
Saline moistened gauze
Basic Steps of Replantation 1. Debridement and tagging of structures 2. Bone fixation 3. Tendon repairs a. Extensor tendon repair b. Flexor tendon repair 4. Nerve repair 5. Arterial repair 6. Venous repair 7. Skin closure
Within
Sealed plastic bag
Debridement and Tagging Structures Into
Saline ice slurry
This is one of the essential steps that make the rest of the procedure easier if done properly. The wound is extended usually with mid lateral incisions on both sides. The devitalized and contaminated tissues are then debrided. After this, the bone is shortened before the tendon ends are sharply trimmed. The digital neurovascular bundles are then isolated and tagged under loupe magnification or a microscope. Tagging can be done with clips or ties. Clips are easy and fast, but they are more expensive.
Bone Fixation FIG. 5.8.1 Transport of the amputated part: irrigated, wrapped in moist gauze, placed in plastic bag, and put inside the ice bath. (Reproduced from Dzwierzynski WW. Replantation and revascularization. In: Neligan P, Chang J, eds. Plastic Surgery, 3rd ed, vol 6. London: Elsevier Saunders; 2013.)
10. Supplies needed The availability and preparation of the needed supplies can have a significant effect on easing the stress endured by the operating surgeons. a. Microscope b. Tourniquet c. Bipolar forceps d. Micro-instruments including micro scissors, jeweler’s forceps, vessel dilator, and double-vessel clamps e. Micro-sutures (9-0 or 10-0) f. Solutions (heparin, papaverine) g. Ligature clips
SURGERY The fundamental order of the replantation is to repair larger, deeper structures such as bone and tendon first, which needs gross manipulation, followed by the repair of superficial structures such as vessels and nerves, which require microscopical repair. However, the exact sequence is more dependent on the surgeon’s preference. The essential argument in the repair sequence is whether to repair the artery or vein first after the other structures have been connected. Performing the venous anastomoses before the arterial anastomoses
Bone shortening is one of the critical steps. It allows the vessels and nerves to be repaired primarily without tension and diminishes the need for graft and skin coverage. It is wise to shorten from the amputated parts rather than from the proximal end so that a good length of the stump remains in the event of replantation failure. Rigid internal fixation of the bone allows early therapy and better outcomes. Various methods can be used to fix the bone (Fig. 5.8.2): • Crossed K-wires • The 90-90 intraosseous wiring • Lister’s technique (Fig. 5.8.3) Metacarpal fractures can be fixed with multiple K-wires if there are multiple amputations. More proximal fractures can be rigidly fixed with plates and screws (refer to Chapter 2.4 for more details on bone fixation).
Tendon Repair This is probably one of the most important steps determining the final outcome of the replantation. The surgeon must avoid the inclination to perform this step in haste. We recommend doing the epitendinous sutures first with 6-0 monofilament suture to prevent the bunching of the tendon ends. 4-0 Kessler suture repair is done with the slit in the proximal tendon to bury the knot inside the tendon. It is supplemented with 4-0 horizontal mattress suture for a four-strand repair. A fourstrand or more repair allows early active motion in post-operative therapy (refer to Chapter 2.3 for more details on tendon repair). Extensor tendons are repaired with 3-0 horizontal mattress sutures.
Vein Repair An additional vein should be anastomosed in comparison to the number of arteries anastomosed. The optimal location to find adequate veins is over the dorsum of the finger. A thick dorsal skin flap is raised superficial to the paratenon of the extensor tendon. The venous plexus can be
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SECTION 5 Hand Surgery Cross section of digit Dorsal veins
Extensor tendon: Central slip Lateral band
Bone
Flexor tendon
Digital nerve (volar)
A
B
Digital artery (volar)
D
C
Extensor tendon
E
F
H
G
FIG. 5.8.2 Techniques of bony fixation: (A) Crossed K-wires, (B) single longitudinal K-wire, (C) interosseous wire and K-wire, (D) 90-90 wiring, (E) intramedullary fixation, (F) H-plate fixation, (G) compression plate, and (H) Lag screw. (Reproduced from Dzwierzynski WW. Replantation and revascularization. In: Neligan P, Chang J, eds. Plastic Surgery, 3rd ed, vol 6. London: Elsevier Saunders; 2013.)
Digital artery Digital nerve
FIG. 5.8.4 A mid-lateral incision of the amputated part for better access to dorsal veins. (Reproduced from Dzwierzynski WW. Replantation and revascularization. In: Neligan P, Chang J, eds. Plastic Surgery, 3rd ed, vol 6. London: Elsevier Saunders; 2013.)
visualized on the underside of the skin flap. One of the veins is selected and dissected to get adequate length by ligating and dividing its multiple branches. There should be no hesitancy in performing a reverse vein graft if it is required to obtain a tension-free repair (Fig. 5.8.4).
Arterial Repair
A
B
FIG. 5.8.3 X-ray showing Lister’s technique: single intraosseous wiring (24g wire) with oblique K-wire (1.2 mm) fixation. (A) PA view. (B) Lateral view.
Both ulnar and radial digital arteries should be repaired. If this is not possible, the dominant artery must be repaired. The ulnar digital artery is the dominant artery in all fingers except the little finger. However, the position of the thumb poses difficulties in the repair of the ulnar digital artery. Performing a vein graft on the distal part in advance makes it easier to repair the ulnar digital artery of the thumb.4 Digital arteries must be carefully inspected under the microscope. A red line sign (bruising of the skin along the artery) should arouse suspicion of injury to the artery or its branches. A paprika sign (speckled artery due to rupture of vasa vasorum) or a ribbon sign (corkscrew appearance of the arteries) must be noted. The artery must be trimmed until a fresh margin is clearly visible with a good spurt of blood. If the flow is poor, the artery can be flushed with papaverine and heparinized saline. There should not be any hesitancy in obtaining a vein graft if there is tension.
CHAPTER 5.8 Replantation
A
B
D
373
C
E
FIG. 5.8.5 A 3-year-old boy involved in a road traffic accident sustained an amputation of the left index finger through the proximal phalanx. (A) Amputated finger. (B) Left hand with amputated index finger, dorsal view. (C) Left hand with amputated index finger, volar view. (D) Left hand after replanted index finger, dorsal view. (E) Left hand after replanted index finger, volar view.
Nerve Repair The key to nerve repair is a tension-free repair. A nerve graft must be considered if a single 8-0 suture is not able to hold the nerve together. There are various donor sites for nerve grafts. Common sites for digital replantation include the posterior interosseous nerve, the medial antebrachial cutaneous nerve, and the sural nerve. The end is cut fresh until the fascicles protrude from the end, and an epineural repair is performed with 9/0 suture. Generally, the replanted finger acquires protective sensation with two-point discrimination under 12 mm.5
Skin Closure The skin should be approximated with loose intermittent absorbable sutures after meticulous hemostasis. The remaining raw area can be left for secondary healing if it is small, or it can be covered with a
split-thickness skin graft. A skin graft can also be placed directly over the vessels. A prophylactic fasciotomy is typically performed in major replantations to accommodate the venous congestion (Fig. 5.8.5).
POST-OPERATIVE CARE 1. Dressing: The wound is covered with non-adherent dressing and loose gauze. The dressing should be loose and bulky. A splint is applied to immobilize the hand. 2. Elevation: The limb is elevated above the level of the heart. 3. Hydration: Hydration is maintained with oral fluid so as to decrease the hyperviscosity. Caffeinated drinks are discouraged. 4. Analgesics: Enough analgesia should be given to control pain, which causes vasoconstriction.
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SECTION 5 Hand Surgery
5. Monitoring: Depending on the resources of the hospital, moni toring of the digit can be performed by pulse oximetry on the replanted digit, or simply observation for quick capillary refill, without congestion. 6. Smoking avoidance: Smoking is prohibited because nicotine has a vasoconstrictive effect. 7. Antibiotics: Broad-spectrum antibiotics are given for a week as per the preference of the surgeon. 8. Anticoagulation: Different surgeons have their own preference. The available options include aspirin, Dextran, and heparin. 325 mg of aspirin is given daily for several days as per the surgeon’s preference. 9. Therapy There is a general guideline that is modifiable depending on multiple factors, including: • Nature of the injury • Level of replantation • Surgery performed • Patient’s general medical health • Associated injuries • Patient’s psychosocial status and ability to participate in therapy
1 Week • First dressing change. • Dorsal splint is fabricated in lumbrical plus position. • Therapy started with early protective motion with passive wrist flexion to produce finger extension and passive wrist extension to produce finger flexion via the tenodesis effect. • Active and passive range of motion to all uninvolved fingers.
MANAGING COMPLICATIONS Replantation is desired by most patients. However, it is associated with multiple complications including failure of replantation. It is therefore extremely important to counsel the patients regarding all associated complications. Here we describe the common complications.
Loss of Replanted Digit The replantation might fail because of the thrombosis of the arterial inflow and/or venous outflow. Therefore careful monitoring should be done, and the patient should be taken for re-exploration if necessary.
Malunion and Non-Union There is a chance of malunion because of inadequate fixation of bone in haste. The non-union rate is about 16%, but it can be reduced by better techniques of rigid fixation.6
Joint Stiffness The replanted finger will likely have less motion than a normal finger.7 Therefore early range of motion of the replanted finger and also the adjacent fingers should be encouraged.
Tendon Adhesions Tendon repair is one of the most important steps determining the final outcome. Meticulous tendon repair and early mobilization are essential in maximizing tendon gliding. The patient may need secondary tenolysis to improve the range of motion. In one study, 60% of patients required a secondary tenolysis procedure.7
2 Weeks
Sensory Return and Cold Intolerance
• Scar massage if wound is healed. • Continue tenodesis and protective motion within the limit decided during intraoperative period.
There is 36% to 77% probability of having protective sensation in a replanted finger. This is dependent on the level of amputation and mechanism of injury.8
4 Weeks • Composite finger flexion is initiated.
6 Weeks • Splint off except for heavy, uncontrolled tasks. • Volar extension splint for nighttime use if a flexion contracture is developing. • Differential tendon gliding is initiated. • Gentle blocking exercises are initiated.
8 Weeks • Progressively add light resistive exercises. • Progress toward strengthening exercises. • Continue light functional activities.
12 Weeks • Return to work gradually (Fig. 5.8.6).
KEY PRINCIPLES • Replantation is a necessary procedure for hand surgeons and highly desired by patients. It should be considered in patients, except in major replantation with more than 12 hours of cold ischemia time or 6 hours of warm ischemia time. • The patient must be counseled in detail regarding all the possible associated complications and the expected outcomes. • The mechanism of injury is important to determine which cases may be suitable for replantation. • Replantation follows a precise order that streamlines a very complex operation. • A meticulous tendon repair is a key step in determining the ultimate outcome.
CHAPTER 5.8 Replantation
B
A
C
D
E
F
FIG. 5.8.6 A 24-year-old man caught his right thumb in the spokes of a motorbike wheel, sustaining a right thumb amputation through the distal phalanx. (A) Right thumb after debridement and identification of digital arteries. (B) Right thumb, dorsal view. (C) Amputated thumb. (D) Right thumb after replantation. (E) Right thumb after 3 months, dorsal view. (F) Right thumb after 3 months, volar view.
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KEY REFERENCES 1. Malt RA, McKhann CF. Replantation of severed arms. JAMA. 1964;189:716. 2. Komatsu S, Tamai S. Successful replantation of a completely cut-off thumb. Plast Reconstr Surg. 1964;43:374. 3. Dzwierzynski WW. Replantation and revascularization. In: Neligan PC, Chang J, eds. Plastic Surgery. 3rd ed, vol 6. London: Elsevier Saunders; 2013:229. 4. Jazayeri L, Klausner JQ, Chang J. Distal digital replantation. Plast Reconstr Surg. 2013;132:1207–1217.
5. Dellon AL. Sensory recovery in replanted digits and transplanted toes: a review. J Reconstr Microsurg. 1986;2:123–129. 6. Whitney TM, Lineaweaver WC, Buncke HJ, et al. Clinical results of bony fixation methods in digital replantation. J Hand Surg Am. 1990;15A:328. 7. Riker B, Vasconez HC, Mentzer RM Jr. Replantation: past, present, and future. J Ky Med Assoc. 2004;102:247–253. 8. Gelberman RH, Urbaniak JR, Bright DS, et al. Digital sensibility following replantation. J Hand Surg. 1978;3:313.
SYNOPSIS The term replantation is used when there is surgical reattachment of a completely amputated body part. In contrast, when there is some tissue still attached, and reattachment of this incompletely amputated part requires microsurgical repair of the vessels, this is called revascularization. Malt and McKhann performed the first successful upper arm replantation in 1962,1 and Komatsu and Tamai reported the first successful replantation of a digit in 1968.2 Since then, microsurgery and replantation have been a basic part of training and routine practice for hand surgeons. Even the best available hand prosthesis has not been able to entirely replicate the function of the hand as effectively as prostheses for the lower extremities. Furthermore, cultural and religious practices in certain countries place a particular emphasis on the presence of all body parts upon death. Therefore replantation is becoming increasingly important in all countries, regardless of socioeconomic conditions. Although microsurgery has seen considerable advances in recent years, hand surgeons have been increasingly critical with regard to outcomes of replantation.3 It is vital to understand that the successful outcome of the replantation does not just depend on microsurgical repair of the vessels but also on restoration of bone, tendon, nerve, and skin. Tendon repair is likely to be the most important step for better long-term outcome of the replantation.
CLINICAL PROBLEM The need for a detailed history focuses on the health of the patient and the cause of the amputation. The key points to be considered are enumerated later, and a summary of the relative indications and contraindications is listed in Table 5.8.1.
Age Younger patients may have better outcomes with nerve and tendon repair. Children may have more technically demanding surgery because of the small caliber of the vessels.4 Older patients are more likely to have systemic diseases and atherosclerosis of the vessels.
Occupation The patient’s occupation and hobbies may help determine whether s/he requires gross or fine motor function of the hand. For example, a construction worker may be better served by a completion amputation and early return to work, whereas a pianist may wish all efforts at replantation to be made.
Associated Injuries If the amputation is associated with life-threatening major injuries, it may be wise not to perform replantation. The overall patient is more important than the digit.
Warm Ischemia Time This is more critical for major replantation in the hand and more proximally, where there is significant muscle that may become ischemic. Amputation proximal to the radio-carpal joint results in irreversible changes leading to myoglobinuria and renal failure if replanted beyond 6 hours of warm ischemia time. However, this time length is much longer in a finger, where there is very little muscle tissue.
Etiology and Mechanism of Injuries A detailed history of the mechanism of injury provides information to foreseeing the severity of injury and the likelihood of success. Sharp cut or guillotine amputations have clean margins and are best suitable for replantation, whereas crush and avulsion injuries may have tissue loss and multiple-level injuries. Wound contamination increases the risk of infection and requires radical debridement.
Associated Conditions Associated comorbidities such as diabetes, coronary artery disease, chronic obstructive pulmonary disease, history of smoking, drug dependence, and psychiatric illness are negative factors for replantation.
PRE-OPERATIVE MANAGEMENT Physical Examination Examining the patient as a whole is very important. There is a tendency to mistakenly exclude other pertinent signs that may lie outside our area of expertise. However, general examination should always precede the focused examination because it helps avoid the risk of missing the major injuries. In cases of trauma, a full body survey should be performed to rule out other injuries.
General Examination Determining the general health of the patient is critical for pre-operative decisions such as the specific procedure, required preparation, and type of anesthesia. In most cases of replantation, the patient should be healthy enough for a long time period of general anesthesia.
369
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SECTION 5 Hand Surgery
TABLE 5.8.1 Indications/Contraindications
for Replantation Indications
Contraindications
1. Pediatric amputation 2. Thumb 3. Multiple fingers 4. Patient desire
1. Major replantation with prolonged warm ischemia time 2. Associated with life-threatening injuries 3. Multiple-level amputation 4. Severe avulsion or crush 5. Severe contamination 6. Severe comorbid conditions 7. Severe psychiatric illness 8. Age >70 years
Regional Examination The whole limb should be examined so as not to miss proximal injuries.
Focused Examination Both the limb and the amputated part should be examined thoroughly. It is typically better to conduct the gross examination during the initial presentation of the patient in the emergency department, followed by a thorough, detailed evaluation in the operating room. This approach saves time and reduces the unnecessary hassles of insufficient lighting and supplies.
Factors Requiring Evaluation • • • •
Single-digit vs multiple-digit injury Level of amputation Clean cut vs crush/avulsion mechanism Amount of contamination
COUNSELING Patients and their relatives almost always desire the replantation of any part of their body. However, they are typically not aware of the required procedure in detail, its associated risks, the cost, and the potential complications and outcomes of the surgery. It is therefore the responsibility of the operating surgeon to discuss the proposed procedure in detail so as to facilitate the making of well-informed decisions by the patient. The likelihood of completion amputation should be emphasized.
Topics to Be Discussed 1. Duration of surgery, post-operative therapy, and length of hospital stay. 2. Likelihood of success. 3. Possibility of multiple surgeries for re-exploration, re-revascularization, and secondary surgeries. 4. Possible need for blood transfusion. 5. Possible need for skin, vessel, and nerve grafts. 6. Intensive rehabilitation and time off from work, 7. Expected outcome in terms of function, appearance, and sensibility. 8. Cost. 9. Options of alternate surgeries and their outcomes, including completion amputation.
INVESTIGATIONS Routine tests should be performed to determine the general health of the patient, risks and complications of blood loss, and suitability for the procedure. Tests, depending on individual need, include:
1. Basic blood tests: a. Complete blood count b. Blood type and crossmatch for major replantations c. Renal function test if indicated 2. Radiograph a. x-ray of the proximal extremity and the amputated part should be taken b. Chest x-ray if indicated 3. Electrocardiogram if indicated
EMERGENCY MANAGEMENT AND PREPARATION The patient should be stabilized before being taken to surgery. 1. Analgesia Adequate analgesia should be given because excessive pain results in vasoconstriction. It also has the added benefit of reducing patient anxiety. 2. Tetanus prophylaxis This should be given if the booster dose has been given at least 5 years prior or if the immunization history is uncertain. 3. Antibiotics A first-generation cephalosporin usually suffices. Aminoglycoside and metronidazole can be administered if indicated, in cases of severe contamination. Penicillins should be administered in the case of farmyard injuries. 4. Blood and fluids Patients with amputations, especially above the radio-carpal joint, are at a high risk of losing significant amounts of blood at the amputation site. Blood transfusions may therefore be necessary. Patients should be well hydrated to reduce the likelihood of hyperviscosity. 5. Urinary catheter placement Replantation procedures are typically long in duration, and an indwelling catheter is therefore recommended. This has the added benefit of serving as a useful indicator of the patient’s hydration status intraoperatively and post-operatively. 6. Preparation of the amputated part The parts should be irrigated and wrapped with saline-soaked gauze. The part is then placed in a plastic bag, which is then placed in an ice bath. This allows cooling of the part while avoiding direct contact with ice or saline (Fig. 5.8.1). 7. Proximal extremity In such injuries, the patient is usually taken to the operating room immediately. Therefore simple irrigation and a moist dressing are usually sufficient. Control of bleeding should be achieved with pressure dressings rather than blind attempts at clamping or ligation, which is invariably inefficient and risks unnecessary vessel and nerve damage. 8. Team call A team approach is always preferred for expedited management and reduction of surgeon fatigue. This is particularly important in major replantation and in multiple-digit replantations. 9. Bench work Effective bench work reduces intraoperative time. While the patient is being stabilized in the emergency department and transferred, the operating surgeon can make effective use of this time to prepare the amputated part for the procedure even before the patient is brought into the operating room. Specifically, the amputated part is cleaned, evaluated thoroughly under the microscope, and debrided. Important structures are tagged for ease of identification later.
CHAPTER 5.8 Replantation Early care of amputated part
Amputated part
371
minimizes blood loss and ensures that the technically most demanding step is completed before the tourniquet is released. Conversely, performing the arterial anastomosis before the venous anastomosis allows identification and selection of the veins with good flow. The arterial repair is preferably done first in distal replantation procedures because it is easier to identify ideal veins after, and in major replantations it is part of an effort to decrease the warm ischemia time.
Saline moistened gauze
Basic Steps of Replantation 1. Debridement and tagging of structures 2. Bone fixation 3. Tendon repairs a. Extensor tendon repair b. Flexor tendon repair 4. Nerve repair 5. Arterial repair 6. Venous repair 7. Skin closure
Within
Sealed plastic bag
Debridement and Tagging Structures Into
Saline ice slurry
This is one of the essential steps that make the rest of the procedure easier if done properly. The wound is extended usually with mid lateral incisions on both sides. The devitalized and contaminated tissues are then debrided. After this, the bone is shortened before the tendon ends are sharply trimmed. The digital neurovascular bundles are then isolated and tagged under loupe magnification or a microscope. Tagging can be done with clips or ties. Clips are easy and fast, but they are more expensive.
Bone Fixation FIG. 5.8.1 Transport of the amputated part: irrigated, wrapped in moist gauze, placed in plastic bag, and put inside the ice bath. (Reproduced from Dzwierzynski WW. Replantation and revascularization. In: Neligan P, Chang J, eds. Plastic Surgery, 3rd ed, vol 6. London: Elsevier Saunders; 2013.)
10. Supplies needed The availability and preparation of the needed supplies can have a significant effect on easing the stress endured by the operating surgeons. a. Microscope b. Tourniquet c. Bipolar forceps d. Micro-instruments including micro scissors, jeweler’s forceps, vessel dilator, and double-vessel clamps e. Micro-sutures (9-0 or 10-0) f. Solutions (heparin, papaverine) g. Ligature clips
SURGERY The fundamental order of the replantation is to repair larger, deeper structures such as bone and tendon first, which needs gross manipulation, followed by the repair of superficial structures such as vessels and nerves, which require microscopical repair. However, the exact sequence is more dependent on the surgeon’s preference. The essential argument in the repair sequence is whether to repair the artery or vein first after the other structures have been connected. Performing the venous anastomoses before the arterial anastomoses
Bone shortening is one of the critical steps. It allows the vessels and nerves to be repaired primarily without tension and diminishes the need for graft and skin coverage. It is wise to shorten from the amputated parts rather than from the proximal end so that a good length of the stump remains in the event of replantation failure. Rigid internal fixation of the bone allows early therapy and better outcomes. Various methods can be used to fix the bone (Fig. 5.8.2): • Crossed K-wires • The 90-90 intraosseous wiring • Lister’s technique (Fig. 5.8.3) Metacarpal fractures can be fixed with multiple K-wires if there are multiple amputations. More proximal fractures can be rigidly fixed with plates and screws (refer to Chapter 2.4 for more details on bone fixation).
Tendon Repair This is probably one of the most important steps determining the final outcome of the replantation. The surgeon must avoid the inclination to perform this step in haste. We recommend doing the epitendinous sutures first with 6-0 monofilament suture to prevent the bunching of the tendon ends. 4-0 Kessler suture repair is done with the slit in the proximal tendon to bury the knot inside the tendon. It is supplemented with 4-0 horizontal mattress suture for a four-strand repair. A fourstrand or more repair allows early active motion in post-operative therapy (refer to Chapter 2.3 for more details on tendon repair). Extensor tendons are repaired with 3-0 horizontal mattress sutures.
Vein Repair An additional vein should be anastomosed in comparison to the number of arteries anastomosed. The optimal location to find adequate veins is over the dorsum of the finger. A thick dorsal skin flap is raised superficial to the paratenon of the extensor tendon. The venous plexus can be
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SECTION 5 Hand Surgery Cross section of digit Dorsal veins
Extensor tendon: Central slip Lateral band
Bone
Flexor tendon
Digital nerve (volar)
A
B
Digital artery (volar)
D
C
Extensor tendon
E
F
H
G
FIG. 5.8.2 Techniques of bony fixation: (A) Crossed K-wires, (B) single longitudinal K-wire, (C) interosseous wire and K-wire, (D) 90-90 wiring, (E) intramedullary fixation, (F) H-plate fixation, (G) compression plate, and (H) Lag screw. (Reproduced from Dzwierzynski WW. Replantation and revascularization. In: Neligan P, Chang J, eds. Plastic Surgery, 3rd ed, vol 6. London: Elsevier Saunders; 2013.)
Digital artery Digital nerve
FIG. 5.8.4 A mid-lateral incision of the amputated part for better access to dorsal veins. (Reproduced from Dzwierzynski WW. Replantation and revascularization. In: Neligan P, Chang J, eds. Plastic Surgery, 3rd ed, vol 6. London: Elsevier Saunders; 2013.)
visualized on the underside of the skin flap. One of the veins is selected and dissected to get adequate length by ligating and dividing its multiple branches. There should be no hesitancy in performing a reverse vein graft if it is required to obtain a tension-free repair (Fig. 5.8.4).
Arterial Repair
A
B
FIG. 5.8.3 X-ray showing Lister’s technique: single intraosseous wiring (24g wire) with oblique K-wire (1.2 mm) fixation. (A) PA view. (B) Lateral view.
Both ulnar and radial digital arteries should be repaired. If this is not possible, the dominant artery must be repaired. The ulnar digital artery is the dominant artery in all fingers except the little finger. However, the position of the thumb poses difficulties in the repair of the ulnar digital artery. Performing a vein graft on the distal part in advance makes it easier to repair the ulnar digital artery of the thumb.4 Digital arteries must be carefully inspected under the microscope. A red line sign (bruising of the skin along the artery) should arouse suspicion of injury to the artery or its branches. A paprika sign (speckled artery due to rupture of vasa vasorum) or a ribbon sign (corkscrew appearance of the arteries) must be noted. The artery must be trimmed until a fresh margin is clearly visible with a good spurt of blood. If the flow is poor, the artery can be flushed with papaverine and heparinized saline. There should not be any hesitancy in obtaining a vein graft if there is tension.
CHAPTER 5.8 Replantation
A
B
D
373
C
E
FIG. 5.8.5 A 3-year-old boy involved in a road traffic accident sustained an amputation of the left index finger through the proximal phalanx. (A) Amputated finger. (B) Left hand with amputated index finger, dorsal view. (C) Left hand with amputated index finger, volar view. (D) Left hand after replanted index finger, dorsal view. (E) Left hand after replanted index finger, volar view.
Nerve Repair The key to nerve repair is a tension-free repair. A nerve graft must be considered if a single 8-0 suture is not able to hold the nerve together. There are various donor sites for nerve grafts. Common sites for digital replantation include the posterior interosseous nerve, the medial antebrachial cutaneous nerve, and the sural nerve. The end is cut fresh until the fascicles protrude from the end, and an epineural repair is performed with 9/0 suture. Generally, the replanted finger acquires protective sensation with two-point discrimination under 12 mm.5
Skin Closure The skin should be approximated with loose intermittent absorbable sutures after meticulous hemostasis. The remaining raw area can be left for secondary healing if it is small, or it can be covered with a
split-thickness skin graft. A skin graft can also be placed directly over the vessels. A prophylactic fasciotomy is typically performed in major replantations to accommodate the venous congestion (Fig. 5.8.5).
POST-OPERATIVE CARE 1. Dressing: The wound is covered with non-adherent dressing and loose gauze. The dressing should be loose and bulky. A splint is applied to immobilize the hand. 2. Elevation: The limb is elevated above the level of the heart. 3. Hydration: Hydration is maintained with oral fluid so as to decrease the hyperviscosity. Caffeinated drinks are discouraged. 4. Analgesics: Enough analgesia should be given to control pain, which causes vasoconstriction.
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5. Monitoring: Depending on the resources of the hospital, moni toring of the digit can be performed by pulse oximetry on the replanted digit, or simply observation for quick capillary refill, without congestion. 6. Smoking avoidance: Smoking is prohibited because nicotine has a vasoconstrictive effect. 7. Antibiotics: Broad-spectrum antibiotics are given for a week as per the preference of the surgeon. 8. Anticoagulation: Different surgeons have their own preference. The available options include aspirin, Dextran, and heparin. 325 mg of aspirin is given daily for several days as per the surgeon’s preference. 9. Therapy There is a general guideline that is modifiable depending on multiple factors, including: • Nature of the injury • Level of replantation • Surgery performed • Patient’s general medical health • Associated injuries • Patient’s psychosocial status and ability to participate in therapy
1 Week • First dressing change. • Dorsal splint is fabricated in lumbrical plus position. • Therapy started with early protective motion with passive wrist flexion to produce finger extension and passive wrist extension to produce finger flexion via the tenodesis effect. • Active and passive range of motion to all uninvolved fingers.
MANAGING COMPLICATIONS Replantation is desired by most patients. However, it is associated with multiple complications including failure of replantation. It is therefore extremely important to counsel the patients regarding all associated complications. Here we describe the common complications.
Loss of Replanted Digit The replantation might fail because of the thrombosis of the arterial inflow and/or venous outflow. Therefore careful monitoring should be done, and the patient should be taken for re-exploration if necessary.
Malunion and Non-Union There is a chance of malunion because of inadequate fixation of bone in haste. The non-union rate is about 16%, but it can be reduced by better techniques of rigid fixation.6
Joint Stiffness The replanted finger will likely have less motion than a normal finger.7 Therefore early range of motion of the replanted finger and also the adjacent fingers should be encouraged.
Tendon Adhesions Tendon repair is one of the most important steps determining the final outcome. Meticulous tendon repair and early mobilization are essential in maximizing tendon gliding. The patient may need secondary tenolysis to improve the range of motion. In one study, 60% of patients required a secondary tenolysis procedure.7
2 Weeks
Sensory Return and Cold Intolerance
• Scar massage if wound is healed. • Continue tenodesis and protective motion within the limit decided during intraoperative period.
There is 36% to 77% probability of having protective sensation in a replanted finger. This is dependent on the level of amputation and mechanism of injury.8
4 Weeks • Composite finger flexion is initiated.
6 Weeks • Splint off except for heavy, uncontrolled tasks. • Volar extension splint for nighttime use if a flexion contracture is developing. • Differential tendon gliding is initiated. • Gentle blocking exercises are initiated.
8 Weeks • Progressively add light resistive exercises. • Progress toward strengthening exercises. • Continue light functional activities.
12 Weeks • Return to work gradually (Fig. 5.8.6).
KEY PRINCIPLES • Replantation is a necessary procedure for hand surgeons and highly desired by patients. It should be considered in patients, except in major replantation with more than 12 hours of cold ischemia time or 6 hours of warm ischemia time. • The patient must be counseled in detail regarding all the possible associated complications and the expected outcomes. • The mechanism of injury is important to determine which cases may be suitable for replantation. • Replantation follows a precise order that streamlines a very complex operation. • A meticulous tendon repair is a key step in determining the ultimate outcome.
CHAPTER 5.8 Replantation
B
A
C
D
E
F
FIG. 5.8.6 A 24-year-old man caught his right thumb in the spokes of a motorbike wheel, sustaining a right thumb amputation through the distal phalanx. (A) Right thumb after debridement and identification of digital arteries. (B) Right thumb, dorsal view. (C) Amputated thumb. (D) Right thumb after replantation. (E) Right thumb after 3 months, dorsal view. (F) Right thumb after 3 months, volar view.
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KEY REFERENCES 1. Malt RA, McKhann CF. Replantation of severed arms. JAMA. 1964;189:716. 2. Komatsu S, Tamai S. Successful replantation of a completely cut-off thumb. Plast Reconstr Surg. 1964;43:374. 3. Dzwierzynski WW. Replantation and revascularization. In: Neligan PC, Chang J, eds. Plastic Surgery. 3rd ed, vol 6. London: Elsevier Saunders; 2013:229. 4. Jazayeri L, Klausner JQ, Chang J. Distal digital replantation. Plast Reconstr Surg. 2013;132:1207–1217.
5. Dellon AL. Sensory recovery in replanted digits and transplanted toes: a review. J Reconstr Microsurg. 1986;2:123–129. 6. Whitney TM, Lineaweaver WC, Buncke HJ, et al. Clinical results of bony fixation methods in digital replantation. J Hand Surg Am. 1990;15A:328. 7. Riker B, Vasconez HC, Mentzer RM Jr. Replantation: past, present, and future. J Ky Med Assoc. 2004;102:247–253. 8. Gelberman RH, Urbaniak JR, Bright DS, et al. Digital sensibility following replantation. J Hand Surg. 1978;3:313.