LWWUS_BTH_thues-14-14 175..180

TECHNIQUE

Second-Toe Transfer for Traumatic Thumb Amputation in Children Under 5 Years: Bone and Soft-Tissue Growth German Wolff, MD, and Carolina Posso, MD

Background: Posttraumatic thumb amputations in children under 5 years are uncommon. The final clinical long-term results have been reported shortly in literature. We report our clinical experience in children under 5 years with traumatic amputation of the thumb that were reconstructed using a second-toe transfer. Materials and Methods: There were 7 boys and 2 girls between the ages of 1 and 5 years. The follow-up was between 6 and 14 years. The average age at the time of transfer was 2.8 years, and the average follow-up was 10.7 years (range, between 6 and 14 y). The most frequent cause of amputation was avulsion (33.3%). Results: All the transferred toes survived and achieved bone union and static 2-point discrimination was averaged at 5 mm. They acquired good prehensile pinch and grasp. All of the structures of the transferred toes showed substantial growth. Conclusions: Second-toe transfer for traumatic amputation of the thumb continues to be one of the best choices. Children require secondary procedures less often and in some cases late functional recovery can be expected. It is a safe procedure and there are fewer complications and a better success rate. Key Words: thump amputation, children, toe transfer, good results (Tech Hand Surg 2014;18: 175–180)

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osttraumatic thumb amputations in children under 5 years are uncommon. Technical remarks and long-term clinical results have been reported shortly in literature. Wei et al1 published the first report of second-toe transfer, in thumb reconstruction after traumatic amputations in children, where he includes 28 patients, between 3 and 16 years; in 2003, he published another report with 33 patients, with a range of age between 2 and 16 years.2 Previous reports mostly refer to thumb reconstruction after congenital amputations.3–9 Several techniques in thumb reconstruction have been described depending on the level of the amputation.10,11 Indications for thumb reconstruction have been described by Merle and Dautel12 and others,13,14 according to the level of amputation, where you can use great-toe or second-toe transfer. Advantages and disadvantages of both techniques have been discussed and were summarized by Wei et al,15 who compares these techniques: better esthetic and functional results are achieved on the hand using great-toe transfer, but results are better for the donor foot when using second-toe transfer. When including all variables of comparison, esthetic and functional results are similar.

From the Plastic and Reconstructive Surgery Service, University of Antioquia, Medellıń, Colombia. Conflicts of Interest and Source of Funding: The authors report no conflicts of interest and no source of funding. Address correspondence and reprint requests to Carolina Posso, MD, Plastic and Reconstructive Surgery Service, University of Antioquia, Carrera 51d No. 62-29, 12345 Medellıń, Colombia. E-mail: [email protected]. Copyright r 2014 by Lippincott Williams & Wilkins

Techniques in Hand & Upper Extremity Surgery

The purpose of this article is to present the esthetic and functional results in second-toe transfer performed in children under 5 years, and to assess the potential bone and soft-tissue growth through radiographic analysis and clinical measures.

MATERIALS AND METHODS A retrospective study was made between September of 1993 and August of 2007, reporting our clinical experience in children under 5 years with traumatic amputation of the thumb that were reconstructed using a second-toe transfer at the Plastic Surgery Service of the University of Antioquia, Hospital Universitario San Vicente de Pau´l. We included 7 boys and 2 girls between the ages of 1 and 5 years. The followup was between 6 and 14 years.

SURGICAL TECHNIQUE The surgical technique used follows the directions described by Manktelow.16 Hand dissection is started and includes: linear skin insicion between volar and dorsal region, identification of volar digital nerves, flexor pollicis longus, the radial dorsal artery, the cephalic vein, and extensor tendons. The vascular pedicle is localized at the first digital space of the foot,2 where lateral and medial digital branches of the great toe and second toe, respectively, were identified and proximal dissection was performed until the first dorsal metatarsal artery was found. Several anatomic variations of the trajectory of the artery related to the first dorsal interosseous muscle have been described,17–19 but frequently it lies dorsal to the muscle and underneath the deep metatarsal ligament in 18% to 78% of the cases20; in other cases, it can be diminutive or absent, showing dominance of the plantar system. Then, identification of all structures on the plantar and dorsum aspects of the foot is performed. Finally metatarsal osteotomy as in a digital ray amputation or metatarsophalangeal disarticulation is made according to the osseous length required. Bone fixation is made with Kirschner wires and/or by suturing the articular capsule according to the amputation level, and maintained for 3 weeks. The vascular anastomoses is started with the vein, and then the artery, to avoid excessive bleeding, using 10-0 nonabsorbable monofilament. First, the extensor tendons are repaired in hyperextension to compensate the natural flexion of the joints in toes, and then flexor tendon, volar, and dorsal nerves. One of the patients requires a skin graft to close the soft-tissue defect without any tension. Finally, a bulky above-elbow splint is fashioned. Clinical monitoring during the postoperative period is performed closely, especially during the first 3 days. A 3 mg/kg dose of aspirin was prescribed for 1 month starting the day after surgery. Patients stayed at the hospital for 7 days. A previously designed protocol was followed during the rehabilitation phase.21 Movements were restricted until the third day, from which control passive motion was started for the next 4 weeks. After this period, active motion was started for 2 more weeks, until normal development of daily and

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vocational activities were achieved, which usually occurred between the seventh and eighth weeks.


TABLE 2. Level of Amputation

Level of Amputation

RESULTS In the period from September of 1993 to August of 2010, 9 toe transfers were performed on the same number of patients, to reconstruct postraumatic amputations of the thumb. The average age at the time of transfer was 2.8 years (range, between 1 and 5 y). The average follow-up was 10.7 years (range, between 6 and 14 y). Hand-held Doppler studies were performed on every patient. Preoperative arteriography was not made on any patient. The most frequent cause of amputation was avulsion (33.3%) (Table 1). The amputation level is shown on Table 2. According to the Merle-Dautel classification, 66% of the cases correspond to levels 3 and 4. The average surgical time was 8 hours. The average length of hospitalization was 6 days. All the transferred toes survived, achieving a success rate of 100%. There was a case of venous thrombosis, which required thrombectomy and a new end-to-end anastomoses. There was a case of delayed wound healing at the donor site. Two patients needed tenolysis of the extensor of the transferred toe and in 1 case it was necessary to perform a scar revision on one of the hands. In our series, all patients achieved bone union and static 2-point discrimination was averaged at 5 mm. They acquired good prehensile pinch and grasp. None of the patients complained of difficulty in running or jumping. The donor foot maintained satisfactory appearance. All parents noted an increase in function and an improved esthetic aspect of the hand, and were completely satisfied with the final results. All of the structures of the transferred toes showed substantial growth. Soft-tissue growth was registered by the clinical measurement of the diameters of the proximal and distal interphalangeal joints and the length of the transferred toe, the thumb, and the contralateral second toe. Osseous growth was evaluated through persistence of the epiphyseal plates and progressive growth of all of the structures on the transferred toe, the thumb, and the contralateral second toe. Table 3 shows comparative bone and soft-tissue growth of the transferred toes at the end of followup, the thumbs and the contralateral second toes, expressed in percentages, for the 3 representative cases. All measurements were taken the same day after standardized x-rays, using a goniometer, to achieve minimal variation between patients.

REPRESENTATIVE CASES

Level Level Level Level

2 3 4 5

Patients

(distal MCP) (MCP) (metacarpal neck) (metacarpal base)

2 3 3 1

MCP indicates metacarpophalangeal joint level.

Extensor tendons were repaired and digital volar nerves were anastomosed. Flexor pollicis longus was sutured to the flexor of the second toe. The described protocol was followed during the postoperative period. Three years later extensor tenolysis was required on the scar in the dorsum of the hand. Seven years later (final follow-up), the patient achieved normal range of motion, and developed her daily activities without any restrictions (Fig. 2). Static 2-point discrimination averaged 6 mm. Donor site deficit is minimal and esthetic aspect is adequate. The final mean grip strength of the affected hand was 20 kg (contralateral 22 kg) and the mean pinch strength was 5 kg (contralateral 7 kg).

Case 2 A 3-year-old girl had a blunt amputation of his right thumb at the proximal phalange (type 2) 8 months before surgery (Fig. 3). A second-toe transfer of her left foot was made, at the metatarsophalangeal joint, using the described surgical technique. This patient achieved static 2-point discrimination of 7 mm. Figure 4 shows results 14 years after the surgery. The final mean grip strength of the affected hand was 19 kg (contralateral 22 kg) and the mean pinch strength was 4 kg (contralateral 6 kg). Esthetic and functional results for the hand and the donor foot were satisfactory.

Case 3 A 1-year-old boy who suffered a crush amputation of his left thumb through the metacarpophalangeal joint (level 3) is presented. Reconstruction was performed after 2 years with second-toe transfer of his right foot. Three years later it was necessary to correct the scar on the dorsum of the hand. The final follow-up period was 11 years (Figs. 5, 6). Nowadays his active range of motion is normal, static 2-point discrimination averaged at 3 mm. The final mean grip strength of the affected hand was 24 kg (contralateral 27 kg) and the mean pinch strength was 6 kg (contralateral 8 kg). He practices sports and realizes academic work without difficulty.

DISCUSSION

Case 1 A 2-year-old girl sustained a crush amputation of her left thumb through the proximal third of the first metacarpian (type 5) (Fig. 1). Twenty-six months later a second-toe transfer was performed, including the distal third of the metatarsian. The osteosynthesis was made using 0.0625 Kirschner wire; end-toend anastomoses of great saphenous and cephalic veins and first dorsal metatarsal artery to the radial artery were made.

Normal thumb function requires adequate length, sensibility, mobility, stability, and strength. The main goals when

TABLE 3. Comparative Bone and Soft-Tissue Growth for Representative Cases

Length (%) Thumb

TABLE 1. Etiology of Thumb Amputations

Etiology Avulsion Sharp cut Gun shot Crush injury

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Second Toe

Patients Bone Tissue Soft Tissue Bone Tissue Soft Tissue Patients [n (%)] 3 4 1 1

(33.3) (44.4) (11.1) (11.1)

Case 1 6y 7y Case 2 Case 3

95.8 95.6 95 87.7

90 95 90

r

88 91 100

100 93 100

2014 Lippincott Williams & Wilkins



Second-Toe Transfer for Thumb Amputation in Children

FIGURE 1. Clinical and radiological view of thumb and index amputation of the right hand.

reconstructing the thumb include reestablishing function (sensation and opposition) and appearance.22–25 Until now the only method of reconstruction that can reproduce all these goals is the microsurgical digital transfer, using the great toe or the second toe. Multiple reports have been published making reference to thumb reconstruction with digital transfers, where excellent appearance and function were achieved.26–32 Reports of digital transfers in children are uncommon when traumatic amputation is the etiology,1,2 most series show children’s reports with both congenital and traumatic amputations. In all reports the average age is over 5 years, and several reports include adolescents. Our report is made up of 9 children under 5 years who only had traumatic thumb amputations. Indications of thumb reconstruction depend on the level of amputation. Some publications support the second-toe transfer as the method of choice for children4–9; others mention the great toe, without indicating a specific reason.1,2 According

to the 3 main purposes for thumb reconstruction (to reproduce its original function, to keep an adequate esthetic appearance, and to diminish donor site morbidity) second-toe transfer in thumb amputation in children constitutes the best choice, because there is minimal donor site morbidity, and bone and soft-tissue growth is expected, so important asymmetry with the contralateral thumb is reduced, a common problem with the second-toe transfer in adults. In this study the average age of surgery was 2.8 years, whereas in series of Wei and colleagues the average age was 12 and 12.2 years.1,2 The average age in the study of Chang and Jones31 was 5.7 years, but he combined patients with traumatic and congenital amputations. In our study the average time of follow-up was 10.7 years, whereas follow-up times of 3 years1 and 41 months31 were reported in the previously mentioned publications. We did not perform preoperative arteriography on patients presented in this study because it is an invasive and a high-cost procedure; therefore we preferred to use the hand-held Doppler study in all cases.

FIGURE 2. Postoperative result after 7 years. Note the clinical aspect of donor and contralateral foot. r



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FIGURE 3. Level 2 amputation. Initial aspect.

Although from a technical point of view digital toe transfers in children are more complex and represent greater difficulties because of the sizes of the structures,1 in our series the success rate was 100%. Our results are comparable with the ones published in other articles for both traumatic and congenital amputations.1,2,5 In contrast, Gilbert6 reported 1 digital lost in his series of 38 children with congenital amputations, in whom he performed 49 digital transfers; similar results are reported by Chang and Jones31 who achieved a success rate of 96%, with only 1 failure of 23 patients, where he included 5 traumatic amputations. Growth of the transferred segment as a whole, although it might seem obvious for a microsurgical procedure, has not been well documented, and bone growth is reported alone.6,8,31,33 Growth of all structures of the transferred toes in

3 of the 9 patients was documented comparing the thumbs. These results coincide with Gilbert34 affirmations, who said growth is a positive factor when evaluating long-lasting results of surgery performed on children. Previous publications that reveal bone growth of the transferred toes based their analysis on the appearance of open epiphyseal plate on postoperative xrays controls,6,8,35,36 whereas others make reference to the longitudinal growth of the bone.10 Chang and Jones31 proposed radiologic control in 23 digital transferences based on: persistence of epiphyseal plate, serial measurements of bone growth, and comparison with the contralateral second toe which is the best method to evaluate growth. They concluded their analysis saying that potential bone growth is preserved and it can be the same when the transferred toe is compared with the contralateral second toe.

FIGURE 4. Case 2. Clinical and radiologic evidence of growth of the transferred toe compared with the contralateral thumb. Postoperative results after 14 years.


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Second-Toe Transfer for Thumb Amputation in Children

FIGURE 5. Preoperative view.

In 3 of the 9 cases these measurements were made, demonstrating bone growth in all transferred structures. We documented the persistence of open epiphyseal plate throughout time, with follow-up periods ranging between 1 and 11 years. Longitudinal growth of the transferred toe (bone and soft tissue) was verified comparing the length with the normal thumb, and it showed maximum differences of 6.3 mm in soft tissue and 6 mm in bone structures, but when comparing it to the contralateral second toe, the length was almost the same in all cases (case 3). Differences between thumb and transferred toe are expressed in percentages in Table 3, showing bone growth between 87.7% and 95.8%; in contrast, soft-tissue growth was >90% in all cases presented. The transferred toes compared with the contralateral second toe, showed differences in bone growth ranging between 88% and 100% and for softtissue growth between 93% and 100%. Limitations of this study include the possibility of obtaining inaccurate measurements because of the differences in magnification from radiograph to radiograph despite all attempts at standardization.

From a functional point of view, sensitive recuperation was very good, explained by the multiple possibilities of nervous anastomoses.8 In our series static 2-point discrimination averaged at 5 mm, according to other reports with results ranging between 2 and 8 mm.1,2,9,23 All patients achieved adequate endto-end pinch, high-quality prehensile strength and grasp, as it was found in previous reports where reconstruction for both congenital and traumatic amputations were included.1,2,4,5,9,23,37 One case of venous thrombosis was the only vascular complication and was solved through thrombectomy and new anastomoses. Only 2 patients required extensor tenolysis of the transferred toe, because of progressive length and adhesion rupture during the growing period, contrary to the results for adults where this procedure is performed in almost all cases.1,38 Parents’ satisfaction with esthetic and functional results was manifest, and although it is a subjective concept, it agrees with results of other publications.38 None of the patients complained of difficulties in jumping, running, or any daily activities and psychological adaptation was correct.

FIGURE 6. Final result after 11 years: clinical and radiologic growth measures are included. r



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CONCLUSIONS Microsurgical transfer of the second toe for reconstruction after traumatic amputation of the thumb continues to be one of the best choices. Children require secondary procedures less often (especially tenolysis) and in some cases late functional recovery can be expected. It is a safe procedure and there are fewer complications and a better success rate. REFERENCES 1. Wei FC, El-Gammal TA, Chen HC, et al. Toe-to-hand transfer for traumatic digital amputations in children and adolescents. Plast Reconstr Surg. 1997;100:605–609. 2. Wei FC, Mardini S. Reevaluation of the technique of toe-to-hand transfer for traumatic digital amputations in children and adolescents. Plast Reconstr Surg. 2003;112:1870–1874. 3. O’Brien BM, Brennen MD, MacLeod AM. Microvascular free toe transfer. Clin Plast Surg. 1978;5:223. 4. May JW Jr, Smith RJ, Peimer CA. Toe-to-hand free tissue transfer for thumb reconstruction with multiple digit aplasia. Plast Reconstr Surg. 1981;67:205–213. 5. Lister G. Microsurgical transfer of the second toe for congenital deficiency of the thumb. Plast Reconstr Surg. 1988;82:658–665.


19. Yang DY, Gu YD. Thumb reconstruction utilizing second-toe transplantation by microvascular anastomosis. Chin Med J. 1979;92:295–309. 20. Gu YD, Zhang GM, Chen DS. Vascular anatomic variations in second toe transfers. J Hand Surg. 2000;25:277–281. 21. Ma HS, El-Gammal TA, Wei FC. Current concepts of toe to hand transfer: surgery and rehabilitation. J Hand Surg. 1996;9:41–46. 22. Marzke MW. Evolutionary development of the human hand. Hand Clin. 1992;8:1–8. 23. Shin AY, Bishop AT, Berger RA. Microvascular reconstruction of the traumatized thumb. Hand Clin. 1999;15:347–371. 24. May JW Jr. Microvascular great toe to hand transfer for reconstruction of the amputated thumb. In: May JW Jr, Littler JW, McCarthy JG, eds. The Hand. Plastic Surgery.8: 1st ed. Philadelphia: W.B. Saunders; 1990:5153–5183. 25. Emerson ET, Krizek TJ, Greenwald DP. Anatomy, physiology and functional restoration of the thumb. Ann Plast Surg. 1996;36:180–191. 26. O’Brien BM, Morrison WA. Thumb reconstruction. In: O’Brien BM, Morrison WA, eds. Reconstructive Microsurgery. 2nd ed. New York: Churchill Livingstone; 1987:356–369.

6. Gilbert A. Reconstruction of congenital hand defects with microvascular toe transfers. Hand Clin. 1985;1:351–360.

27. Upton J III, Littler JW. Thumb reconstruction: pollicization for traumatic loss. In: Hentz VR, Mathe SJ, eds. The Hand and Upper Limb. Mathes Plastic Surgery.7: 2nd ed. Philadelphia: Saunders Elsevier; 2006:295–316.

7. Buck-Gramcko D. Progress in the treatment of congenital malformations of the hand. World J Surg. 1990;14:715–724.

28. American replantation mission to China: replantation surgery in China. Plast Reconstr Surg. 1973;52:476–489.

8. Vilkki SK. Advances in microsurgical reconstruction of the congenitally adactylous hand. Clin Orthop. 1995;314:45–58.

29. Wei FC, Chen HC, Chuang CC, et al. Microsurgical thumb reconstruction with toe transfer: selection of various techniques. Plast Reconstr Surg. 1994;93:345.

9. Kay S, McGuiness C. Microsurgical reconstruction in abnormalities of children’s hands. Hand Clin. 1999;15:563–583. 10. Wei FC, Lutz BS, Cheng SL, et al. Reconstruction of bilateral metacarpal hands with multiple toe transplantations. Plast Reconstr Surg. 1999;104:1698–1704. 11. Gordon L. Toe transplantation for hand reconstruction. In: Gordon L, ed. Microsurgical Reconstruction of the Extremities. Indications, Technique and Postoperative Care. 1st ed. New York: Springer-Verlag; 1988:95–134.

30. Wei FC, El-Gammal TA, Lin CH, et al. Metacarpal hand: classification and guidelines for microsurgical reconstruction with toe transfers. Plast Reconstr Surg. 1997;99:122–128. 31. Chang J, Jones NF. Radiographic analysis of growth in pediatric microsurgical toe-to-hand transfers. Plast Reconstr Surg. 2002;109:576–582. 32. Wei FC, Silberman RT, Hsu WM. Retrograde dissection of the vascular pedicle in toe harvest. Plast Reconstr Surg. 1995;96:1211–1214.

12. Merle M, Dautel G. Reconstruction du pouce. In: Merle M, Dautel G, eds. La main traumatique. Premier ed. Paris: Masson; 1995:225–274.

33. Kay SP, Wilberg M. Toe to hand transfer in children: part I. Technical aspects. J Hand Surg (Br). 1996;21:723–734.

13. Morrison WA, O’Brien BM, MacLeod AM. Experience with thumb reconstruction. J Hand Surg (Br.). 1984;9:223–233.

34. Gilbert A. Effect of growth on pediatric hand reconstruction. In: Hentz VR, Mathes SJ, eds. The Hand and Upper Limb. Mathes Plastic Surgery.7: 2nd ed. Philadelphia: Saunders Elsevier; 2006:257–280.

14. Lister G. Reconstruction of the hypoplastic thumb. Clin Orthop. 1985;195:52–65. 15. Wei FC, El-Gammal TA. Toe-to-hand transfer: current concepts, techniques, and research. Clin Plast Surg. 1996;23:103–116. 16. Manktelow RT. Toe to thumb transfer. In: Manketelow RT, ed. Microvascular Reconstruction. 1st ed. Berlin: Springer-Verlag; 1986:165–183. 17. Gilbert A. Composite tissue transfer from the foot: anatomic basis and surgical technique. In: Daniller A, Stranch B, eds. Symposium on Microsurgery. St. Louis: C.V. Mosby; 1976. 18. Leung PC, Wong WL. The vessels of the first metatarsal web space. An operative and radiographic study. J of Bone and Joint Surg. 1983;65A:235–238.


35. Van Beek AL, Wavak PW, Zook EG. Microvascular surgery in young children. Plast Reconstr Surg. 1979;63:457–462. 36. Nunley JA, Spigel PV, Goldner RD, et al. Longitudinal epiphyseal growth after replantation and transplantation in children. J Hand Surg (Am). 1987;12:274–279. 37. Schenken M, Wiber M, Kay SP, et al. Precision grip function after free toe transfer in children with hipoplastic digits. J Plast Reconstr Aesthet Surg. 2007;60:13. 38. Rivas S, Lopez-Gutierrez JC, Lovic A, et al. Doble transferencia de dedo de pie a la mano en ninõ con simbraquidactilia [Double toe to hand transfer in children with symbrachydactyly]. Cir Pediatr. 2006;19:173–176.

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