Geoffrey G. Hallock
TRANSIENT SINGLE-DIGIT ECTOPIC IMPLANTATION ABSTRACT
The concept of vascularized tissue transfer to an ectopic or anatomically incorrect location, made possible by the reestablishment of circulation, is really a basic principle of microvascular reconstructive surgery. Whenever possible, the replantation of amputated tissue, allowing restoration of normal anatomic relationships, would be preferable.1 However, contraindications to immediate replantation, such as a wide zone of injury, multiple levels of injury of the part, or an extensive nerve defect, are well recognized.2 Another alternative to complete replantation may be the salvage of pristine portions in situ, so as to preserve limb coverage and maximal length, without sacrifice of another uninvolved donor site.3 In the exceptional case, the amputated part may be preserved for an extended period of time by temporary ectopic implantation, to permit conservative serial debridement of the injured region, while radical debridement necessary for primary replantation may preclude any eventual restoration of function.45 Previously reported examples of temporary ectopic implantation have demonstrated only minimal restoration of hand function.45 One may postulate that at the digit level, just as in immediate replantation, 1 better function could be expected to justify such an unusual approach for salvaging a single finger.
Downloaded by: NYU. Copyrighted material.
Although immediate replantation of an amputated digit is always preferable, mitigating circumstances (such as a severe concomitant injury involving the appropriate recipient neurovascular structures) might preclude such an attempt altogether. However, if these local structures have the potential, following adequate debridement and/or other tissue transfer, to accept this digit later, than an alternative for transient storage for delayed replantation should be considered. The deep inferior epigastric vessels are a recognized convenient site that could provide temporary ectopic revascularization of such a solitary finger. An example of this approach for thumb preservation is presented, although amputation of the hand before performing the secondary transfer unfortunately proved prudent.
CASE REPORT A 60-year-old male suffered a crush avulsion injury to his distal right non-dominant upper extremity (Fig. 1). The wound was contaminated with grease and garbage. The thumb was completely amputated at the carpometacarpal joint, and arrived in a separate container. Initially, the family and patient desired replantation. Further exploration in the operating room demonstrated an intact dorsal skin bridge to the hand for venous outflow. Both the radial and ulnar arteries were divided at the proximal wrist, with an avulsion of the median, ulnar, and radial sensory nerves from the forearm. A vein graft from the proximal ulnar artery to the superficial palmar arch successfully restored inflow to the hand. Minimal debridement and copious wound irrigation were performed, but it was obvious that sequential debridement would be required, before allowing a safe replantation of the thumb on the more severely injured radial side of the hand. Therefore, the thumb base was debrided, with identification of the digital arteries and with the radial artery being larger. Temporary salvage was elected, since the hand was now viable. A small transverse 309
Division of Plastic Surgery, The Allentown Hospital and Lehigh Valley Hospital Center, Allentown, PA Reprint requests-. Dr. Hallock, 1230 S. Cedar Crest Blvd., Suite 306, Allentown, PA 18103 Accepted for publication January 2, 1992 Copyright © 1992 by Thieme Medical Publishers, Inc., 381 Park Avenue South, New York, NY 10016. All rights reserved.
JOURNAL OF RECONSTRUCTIVE MICROSURGERY/VOLUME 8, NUMBER 4
JULY 1992
• •
yWKlKif -
^
.,
,.
incision was made over the right rectus abdominis muscle about 5 cm below the umbilicus. The lateral rectus sheath was opened longitudinally and the muscle retracted medially to expose the deep inferior epigastric vessels (DIEV) on its undersurface. The DIE artery was traced distally until its external diameter equalled that of the digital artery. After division of the DIEV, dissection toward the groin established a 5-cm long pedicle that easily reached the skin level of the abdominal incision, to facilitate an end-to-end microanastomosis of the arteries (Fig. 2). A large dorsal digital vein then filled to simplify its identification and end-to-end microanastomosis with a DIE vena comitans. The circumference of the skin at the base of the
Figure 1. Crushed right upper extremity with completely amputated thumb.
digit was sutured without tension into the middle of the abdominal incision to complete the ectopic implantation (Fig. 3). A long discourse with the family then ensued about the relative merits of proceeding with multiple long nerve grafts to an insensate hand; the probable need for free flap coverage to restore missing skin at the wrist level; and, of course, a second stage for transferring the thumb back to the hand. A reasonable compromise at day 4 post-injury was to fillet the hand for coverage of a wrist-level disarticulation. The thumb was therefore discarded to allow early prosthesis fitting.
DISCUSSION
Digital artery
Deep inferior epigastr artery
310
Figure 2. Schematic diagram of the deep inferior epigastric vessels for use as a versatile source for potential ectopic revascularization of any body part, here depicted for digital implantation.
Immediate, permanent, ectopic tissue transfer, using only a portion of the amputated part, has frequently been performed as a salvage replantation to achieve local 67 or regional 8 - 10 wound healing, or for concomitant distant injuries involving such transfers from one extremity to the other.1112 Single-stage ectopic placement of the entire part has also been successful, e.g., the foot switch3 or lower leg to contralateral thigh.13 If immediate implantation is not possible, other methods have been devised to forestall the effects of prolonged warm ischemia time. The individual part may be refrigerated to control hypothermia,14 or tissue oxygenation restored indefinitely by perfusion with perfluorocarbons.15 An otherwise useless upper arm has been maintained to serve as a warehouse for delayed vascularized bone grafts to the femur16 and, in another example, replanted in toto to restore thumb viability, so that later the latter could restore a missing contralateral thumb. 3 Godina4 introduced a further variation of these stalling tactics, by using a source for revascularization
Downloaded by: NYU. Copyrighted material.
;
ECTOPIC DIGIT/HALLOCK
sults. The deep inferior epigastric system is a preferential site for ectopic vascular access, as it tapers over a relatively long distance on the undersurface of the rectus muscle, not only allowing dissection of a long vascular leash, but also differential selection of a vascular caliber equal to that of a digital vessel, thus simplifying end-to-end microanastomoses.17 Heroic measures for thumb salvage should always be considered and, on such occasions, ectopic thumb implantation as a prelude to replantation may be justified.
REFERENCES
well outside the zone of injury, to temporarily supply a part. His original choice was the superficial circumflex iliac and superficial epigastric vessels in the groin for finger implantation but this was unsuccessful, because hip flexion by the patient disrupted the microanastomoses. (Godina was later successful in a whole hand implantation using the thoracodorsal vessels.) Mangus17 proposed the deep inferior epigastric vessels as a better alternative, since the DIEV are readily accessible with the patient in a supine position, and the anatomy is more constant than the groin vessels. This proposal has been clinically successful in one reported case for a mid-forearm level amputation.5 Although hand function of extremities successfully replanted from the ectopic location in a second stage has been less than ideal to date,45 it could be anticipated that single digits would have better re-
Downloaded by: NYU. Copyrighted material.
Figure 3. Amputated thumb temporarily implanted on abdomen.
1. Wilson CS, Alpert BS, Buncke HJ, Gordon L: Replantation of the upper extremity. Clin Plast Surg 10:85, 1983 2. Hidalgo DA, Shaw WW: Lower limb replantation. In Shaw WW, Hidalgo DA (eds): Microsurgery in Trauma, Mount Kisco, NY: Futura Publishing, 1987, pp 98-100 3. Colen SR, Romita MC, Godfrey NV, Shaw WW: Salvage replantation. Clin Plast Surg 10:125, 1983 4. Godina M, Bajec ), Baraga A: Salvage of the mutilated upper extremity with temporary ectopic implantation of the undamaged part. Plast Reconstr Surg 78:295, 1986 5. Chernofsky MA, Sauer PF: Temporary ectopic implantation. I Hand Surg 15A:910, 1990 6. Alpert BS, Buncke HJ: Mutilating multidigital injuries: Use of a free microvascular flap from a nonreplantable part. I Hand Surg 3A:196, 1978 7. Chase RA: The damaged index digit: A source of components to restore the crippled hand.) Bone Joint Surg 5OA:1152, 1968 8. Jupiter JB, Tsai TM, Kleinert HE: Salvage replantation of lower limb amputations. Plast Reconstr Surg 69:1, 1982 9. May JW, Gordon, L: Palm of hand free flap for forearm length preservation in nonreplantable forearm amputation: A case report. J Hand Surg 5A:377, 1980 10. [ones NF, Hardesty RA, Goldstein SA, Ward WT: Upper limb salvage using a free radial forearm flap. Plast Reconstr Surg 79:468, 1987 11. Waterhouse N, Moss ALH, Townsend PLG: Lower limb salvage using an extended free radial forearm flap. Br J Plast Surg 37:394, 1984 12. Gumley G, MacLeod AM, Thistlethwaite S, Ryan AR: Case report: Total cutaneous harvesting from an amputated foot—Two free flaps used for acute reconstruction. Br J Plast Surg 40:313, 1987 13. Chen ZW, Zeng BF: Replantation of the lower extremity. Clin Plast Surg 10:103, 1983 14. Thoma A: Storage of a free forearm flap for 55 hours. Plast Reconstr Surg 78:91, 1986 15. Smith AR, van Alphen B, Faithfull NS, Fennema M: Limb preservation in replantation surgery. Plast Reconstr Surg 75:227, 1985 16. Mixter RC, Wood MB: Closure of a defect of the femur with a compound free forearm transfer including both the radius and the ulna. Br J Plast Surg 36:470, 1983 17. Mangus DJ: Ectopic vascularization using the inferior epigastric system. Plast Reconstr Surg 79:495, 1987
311
TRANSIENT SINGLE-DIGIT ECTOPIC IMPLANTATION ABSTRACT
The concept of vascularized tissue transfer to an ectopic or anatomically incorrect location, made possible by the reestablishment of circulation, is really a basic principle of microvascular reconstructive surgery. Whenever possible, the replantation of amputated tissue, allowing restoration of normal anatomic relationships, would be preferable.1 However, contraindications to immediate replantation, such as a wide zone of injury, multiple levels of injury of the part, or an extensive nerve defect, are well recognized.2 Another alternative to complete replantation may be the salvage of pristine portions in situ, so as to preserve limb coverage and maximal length, without sacrifice of another uninvolved donor site.3 In the exceptional case, the amputated part may be preserved for an extended period of time by temporary ectopic implantation, to permit conservative serial debridement of the injured region, while radical debridement necessary for primary replantation may preclude any eventual restoration of function.45 Previously reported examples of temporary ectopic implantation have demonstrated only minimal restoration of hand function.45 One may postulate that at the digit level, just as in immediate replantation, 1 better function could be expected to justify such an unusual approach for salvaging a single finger.
Downloaded by: NYU. Copyrighted material.
Although immediate replantation of an amputated digit is always preferable, mitigating circumstances (such as a severe concomitant injury involving the appropriate recipient neurovascular structures) might preclude such an attempt altogether. However, if these local structures have the potential, following adequate debridement and/or other tissue transfer, to accept this digit later, than an alternative for transient storage for delayed replantation should be considered. The deep inferior epigastric vessels are a recognized convenient site that could provide temporary ectopic revascularization of such a solitary finger. An example of this approach for thumb preservation is presented, although amputation of the hand before performing the secondary transfer unfortunately proved prudent.
CASE REPORT A 60-year-old male suffered a crush avulsion injury to his distal right non-dominant upper extremity (Fig. 1). The wound was contaminated with grease and garbage. The thumb was completely amputated at the carpometacarpal joint, and arrived in a separate container. Initially, the family and patient desired replantation. Further exploration in the operating room demonstrated an intact dorsal skin bridge to the hand for venous outflow. Both the radial and ulnar arteries were divided at the proximal wrist, with an avulsion of the median, ulnar, and radial sensory nerves from the forearm. A vein graft from the proximal ulnar artery to the superficial palmar arch successfully restored inflow to the hand. Minimal debridement and copious wound irrigation were performed, but it was obvious that sequential debridement would be required, before allowing a safe replantation of the thumb on the more severely injured radial side of the hand. Therefore, the thumb base was debrided, with identification of the digital arteries and with the radial artery being larger. Temporary salvage was elected, since the hand was now viable. A small transverse 309
Division of Plastic Surgery, The Allentown Hospital and Lehigh Valley Hospital Center, Allentown, PA Reprint requests-. Dr. Hallock, 1230 S. Cedar Crest Blvd., Suite 306, Allentown, PA 18103 Accepted for publication January 2, 1992 Copyright © 1992 by Thieme Medical Publishers, Inc., 381 Park Avenue South, New York, NY 10016. All rights reserved.
JOURNAL OF RECONSTRUCTIVE MICROSURGERY/VOLUME 8, NUMBER 4
JULY 1992
• •
yWKlKif -
^
.,
,.
incision was made over the right rectus abdominis muscle about 5 cm below the umbilicus. The lateral rectus sheath was opened longitudinally and the muscle retracted medially to expose the deep inferior epigastric vessels (DIEV) on its undersurface. The DIE artery was traced distally until its external diameter equalled that of the digital artery. After division of the DIEV, dissection toward the groin established a 5-cm long pedicle that easily reached the skin level of the abdominal incision, to facilitate an end-to-end microanastomosis of the arteries (Fig. 2). A large dorsal digital vein then filled to simplify its identification and end-to-end microanastomosis with a DIE vena comitans. The circumference of the skin at the base of the
Figure 1. Crushed right upper extremity with completely amputated thumb.
digit was sutured without tension into the middle of the abdominal incision to complete the ectopic implantation (Fig. 3). A long discourse with the family then ensued about the relative merits of proceeding with multiple long nerve grafts to an insensate hand; the probable need for free flap coverage to restore missing skin at the wrist level; and, of course, a second stage for transferring the thumb back to the hand. A reasonable compromise at day 4 post-injury was to fillet the hand for coverage of a wrist-level disarticulation. The thumb was therefore discarded to allow early prosthesis fitting.
DISCUSSION
Digital artery
Deep inferior epigastr artery
310
Figure 2. Schematic diagram of the deep inferior epigastric vessels for use as a versatile source for potential ectopic revascularization of any body part, here depicted for digital implantation.
Immediate, permanent, ectopic tissue transfer, using only a portion of the amputated part, has frequently been performed as a salvage replantation to achieve local 67 or regional 8 - 10 wound healing, or for concomitant distant injuries involving such transfers from one extremity to the other.1112 Single-stage ectopic placement of the entire part has also been successful, e.g., the foot switch3 or lower leg to contralateral thigh.13 If immediate implantation is not possible, other methods have been devised to forestall the effects of prolonged warm ischemia time. The individual part may be refrigerated to control hypothermia,14 or tissue oxygenation restored indefinitely by perfusion with perfluorocarbons.15 An otherwise useless upper arm has been maintained to serve as a warehouse for delayed vascularized bone grafts to the femur16 and, in another example, replanted in toto to restore thumb viability, so that later the latter could restore a missing contralateral thumb. 3 Godina4 introduced a further variation of these stalling tactics, by using a source for revascularization
Downloaded by: NYU. Copyrighted material.
;
ECTOPIC DIGIT/HALLOCK
sults. The deep inferior epigastric system is a preferential site for ectopic vascular access, as it tapers over a relatively long distance on the undersurface of the rectus muscle, not only allowing dissection of a long vascular leash, but also differential selection of a vascular caliber equal to that of a digital vessel, thus simplifying end-to-end microanastomoses.17 Heroic measures for thumb salvage should always be considered and, on such occasions, ectopic thumb implantation as a prelude to replantation may be justified.
REFERENCES
well outside the zone of injury, to temporarily supply a part. His original choice was the superficial circumflex iliac and superficial epigastric vessels in the groin for finger implantation but this was unsuccessful, because hip flexion by the patient disrupted the microanastomoses. (Godina was later successful in a whole hand implantation using the thoracodorsal vessels.) Mangus17 proposed the deep inferior epigastric vessels as a better alternative, since the DIEV are readily accessible with the patient in a supine position, and the anatomy is more constant than the groin vessels. This proposal has been clinically successful in one reported case for a mid-forearm level amputation.5 Although hand function of extremities successfully replanted from the ectopic location in a second stage has been less than ideal to date,45 it could be anticipated that single digits would have better re-
Downloaded by: NYU. Copyrighted material.
Figure 3. Amputated thumb temporarily implanted on abdomen.
1. Wilson CS, Alpert BS, Buncke HJ, Gordon L: Replantation of the upper extremity. Clin Plast Surg 10:85, 1983 2. Hidalgo DA, Shaw WW: Lower limb replantation. In Shaw WW, Hidalgo DA (eds): Microsurgery in Trauma, Mount Kisco, NY: Futura Publishing, 1987, pp 98-100 3. Colen SR, Romita MC, Godfrey NV, Shaw WW: Salvage replantation. Clin Plast Surg 10:125, 1983 4. Godina M, Bajec ), Baraga A: Salvage of the mutilated upper extremity with temporary ectopic implantation of the undamaged part. Plast Reconstr Surg 78:295, 1986 5. Chernofsky MA, Sauer PF: Temporary ectopic implantation. I Hand Surg 15A:910, 1990 6. Alpert BS, Buncke HJ: Mutilating multidigital injuries: Use of a free microvascular flap from a nonreplantable part. I Hand Surg 3A:196, 1978 7. Chase RA: The damaged index digit: A source of components to restore the crippled hand.) Bone Joint Surg 5OA:1152, 1968 8. Jupiter JB, Tsai TM, Kleinert HE: Salvage replantation of lower limb amputations. Plast Reconstr Surg 69:1, 1982 9. May JW, Gordon, L: Palm of hand free flap for forearm length preservation in nonreplantable forearm amputation: A case report. J Hand Surg 5A:377, 1980 10. [ones NF, Hardesty RA, Goldstein SA, Ward WT: Upper limb salvage using a free radial forearm flap. Plast Reconstr Surg 79:468, 1987 11. Waterhouse N, Moss ALH, Townsend PLG: Lower limb salvage using an extended free radial forearm flap. Br J Plast Surg 37:394, 1984 12. Gumley G, MacLeod AM, Thistlethwaite S, Ryan AR: Case report: Total cutaneous harvesting from an amputated foot—Two free flaps used for acute reconstruction. Br J Plast Surg 40:313, 1987 13. Chen ZW, Zeng BF: Replantation of the lower extremity. Clin Plast Surg 10:103, 1983 14. Thoma A: Storage of a free forearm flap for 55 hours. Plast Reconstr Surg 78:91, 1986 15. Smith AR, van Alphen B, Faithfull NS, Fennema M: Limb preservation in replantation surgery. Plast Reconstr Surg 75:227, 1985 16. Mixter RC, Wood MB: Closure of a defect of the femur with a compound free forearm transfer including both the radius and the ulna. Br J Plast Surg 36:470, 1983 17. Mangus DJ: Ectopic vascularization using the inferior epigastric system. Plast Reconstr Surg 79:495, 1987
311
