INTRODUCTION
Reconstruction of pediatric scalp avulsion secondary to injury or defect presents a technical challenge. Case studies report frequent causes of scalp avulsion including dog bites, motor vehicle accidents, heavy machinery, and assaults.1–4 The incidence of dog bites has been extensively studied at the national, state, and local levels; researchers have found that boys aged 6 to 12 years who are bitten by a pit bull disproportionately experience lacerations requiring surgical intervention.5–17
Microsurgical replantation of an avulsed scalp remains the criterion standard but may not always be feasible.17 Other reconstructive options described in the literature include skin grafting, free flap transfer with latissimus flap, or tissue expansion.18–23 When evaluating surgical alternatives, it is necessary to consider the size, depth, and location of the wound on the calvarium, as well as the quality of the surrounding tissue, damage to hair follicles, additional exposure to bacteria (ie, animal bites), and any other comorbidities.
In this case report, the authors present the results of a novel alternative to full-thickness grafts through the use of SkinTE (PolarityTE), an autologous homologous skin construct (AHSC), to reconstruct a subtotal pediatric scalp avulsion. The patient’s family signed informed consent authorizing the authors to publish his clinical data and images in this case report.
CASE PRESENTATION AND PREOPERATIVE PLANNING
A 7-year-old boy presented to the hospital with a subtotal avulsed scalp after being attacked by the family pit bull and German shepherd. The laceration extended irregularly across the glabella approximately 5 cm superior to the supraorbital ridge. The frontalis muscle was torn as well as the temporal branch of the facial nerve. The laceration continued posteriorly bilaterally with the right side approximately 5 cm superior to the right helix and the left approximately 1 cm superior to the left helix. The laceration followed obliquely and ended sharply across the occiput with hair-bearing epidermis intact inferiorly (Figure 1A, B). The size of the avulsion initially was approximately 960 cm2 (32 × 30 cm). No remnant of the avulsed scalp was identified for microsurgical replantation.
;)
Figure 1.: STATUS POSTDEBRIDEMENTA, Front view. B, Side view.
The injury was deep to the periosteum and required multiple trips to the OR for debridement. Once the wound was thoroughly cleaned, the authors decided to place a dermal regeneration template (Integra) to create a neodermis (Figure 2). The size of the template used to cover the soft tissue defect was 27 × 27 cm, and it was placed on the second day after the injury. The patient was subsequently brought back to the OR every few days for dressing changes with a fine mesh occlusive dressing, burn gauze, a gauze bandage roll, and stretch net.
Figure 2.: PLACEMENT OF DERMAL REGENERATION TEMPLATE
Once the dermal regeneration template appropriately incorporated over the exposed calvarium (Figure 3), the authors contemplated options for graft coverage. Because of the extensive size of the defect and the ratio of wound size to child body habitus, the family was primarily concerned with the significant amount of donor site required for split-thickness graft over the dermal regeneration template. Secondarily, the family wanted to make every effort to restore hair-bearing function. After extensive discussion with the family, the authors opted to use an AHSC to reduce donor site morbidity and increase the potential for the regeneration of hair-bearing function.24 This combination of outcomes was not available with alternative reconstructive options.
Figure 3.: WOUND BED STATUS POST-NEODERMAL FORMATION
Because of the 20× expansion ratio of the AHSC, the authors harvested only an 8 × 3-cm full-thickness skin graft from the patient’s left groin; the created defect was closed primarily. The full-thickness graft was sent to the commercial laboratory for processing to activate progenitor cells. The authors then received a 20-mL syringe of expander progenitor cells approximately 72 hours after harvest of the donor site. Based on manufacturer recommendations, the authors then dispersed aliquots of the product over the neodermis (Figure 4A) created by the bilaminar dermal regeneration template and secured the product to the calvarium with the silicon sheet that comes with the product (Figure 4B). They then placed a head wrap on the patient consisting of nonadherent dressing, a gauze bandage roll, stretch net, and a cohesive elastic to secure the product.
Figure 4.: PLACEMENT OF AUTOLOGOUS HOMOLOGOUS SKIN CONSTRUCTA, Aliquots of the product placed over the neodermis. B, Product secured to the calvarium with a silicon sheet.
The patient was seen for dressing changes every 2 weeks for the first 6 weeks and then at three additional visits over the following 24 weeks. The authors noted appropriate epidermis creation with the product use, although through the process the tissue appeared friable and required significant attention and serial wound dressing changes for complete epithelialization (Table 1). There were no complications associated with the donor site, and the family was happy overall that the patient had minimal donor site deficits and skin coverage over this large scalp defect.
Table.: POSTOPERATIVE EPITHELIALIZATION
DISCUSSION
While considering reconstruction with an AHSC, the authors found no articles discussing its use with pediatric scalp defects. They had extensive discussions with the manufacturer as well as the family prior to using this product. Although this product worked successfully to cover the patient’s subperiosteal scalp defect, it was a relatively rigorous process. Serial dressing changes were required; these were performed under sedation because the patient could not tolerate the dressing changes otherwise. As is seen based on the timeline (Table 1), the process ultimately took approximately 24 weeks for epithelialization. Many surgeons might argue that split-thickness skin grafting would have been a better option for this patient. However, because the authors’ goal based on the patient’s and the family’s wishes was to provide the patient with the least amount of donor site morbidity and make every effort to restore hair-bearing function, they opted to use an AHSC.
It is difficult to quantify the cost burden associated with the use of AHSC versus split-thickness grafting, but the AHSC came with a significant burden of time and resources to ultimate coverage in this patient.
One of the big questions was if it was beneficial to use a dermal regeneration template prior to the AHSC. The neodermis helped reduce the risk of osteomyelitis of the calvarial bone in the process of serial dressing changes. Further, with this being the surgeon’s first utilization of the product, he wanted to make sure that he had some level of coverage over the defect prior to exploring alternative solutions to reduce donor morbidity. The dermal regeneration template enabled a grace period to explore other opportunities but also ultimately allowed for a “bailout” of split-thickness skin grafting if the AHSC was unsuccessful. In addition, at the onset of this patient’s injury, the authors did not have the option to use AHSC and therefore used the only dermal regeneration template that was readily available.
A secondary goal of the family was the restoration of hair-bearing function. In discussions with the family, the authors expressed the significant unknown as to whether the patient would develop hair in that space with the use of AHSC. However, a split-thickness skin graft would offer no hope for meaningful hair growth. The family and surgeon ultimately wanted to make every possible attempt to restore the hair-bearing function of the scalp. Unfortunately, based on the most recent assessment, the authors have not yet identified any hair growth in the reconstructed scalp.
Use of an AHSC has the potential to reshape reconstructive algorithms for large soft tissue defects. However, AHSC use is in its infancy, and there is a paucity of literature regarding its use in pediatric soft tissue trauma. In addition, the limitations of the current AHSC products and how best to educate families about AHSC if more surgeons attempt to use it both need to be further elucidated.
Limitations
Long-term follow-up of the patient is required to determine the final result of all the treatments and the extent to which original tissue function is restored.
CONCLUSIONS
Pediatric scalp avulsion is a rare injury that is a reconstructive challenge because of the unique features of scalp tissue. In general, there is no consensus regarding management of this trauma, and multiple reconstructive techniques may need to be used for definitive coverage. Autologous homologous skin constructs are an emerging reconstructive tool that significantly reduces the size of the donor site required and associated donor site complications while also offering the potential for regeneration of functional epithelial tissue.
REFERENCES
1. Yin JW, Matsuo JM, Hsieh CH, Yeh MC, Liao WC, Jeng SF. Replantation of total avulsed scalp with microsurgery: experience of eight cases and literature review. J Trauma 2008;64(3):796–802.
2. Ozek C, Guner U, Bilkay U, et al. Superficial scalp necrosis after replantation. Ann Plast Surg 2001;46(2):197–8.
3. Macias D, Kwon DI, Walker PC, Peterson NR. Microvascular replantation of a composite facial avulsion in a 24-month-old child after dog bite. Microsurgery 2018;38:218–21.
4. Plant MA, Fialkov J. Total scalp avulsion with microvascular reanastomosis: a case report and literature review. Can J Plast Surg 2010;18(3):112–5.
5. Hurst PJ, Hoon Hwang MJ, Dodson TB, Dillon JK. Children have an increased risk of periorbital dog bite injuries. J Oral Maxillofac Surg 2020;78(1):91–100.
6. McLoughlin RJ, Cournoyer L, Hirsh MP, Cleary MA, Aidlen JT. Hospitalizations for pediatric dog bite injuries in the United States. J Pediatr Surg 2020;55(7):1228–33.
7. Basco AN, McCormack ER, Basco WT Jr. Age- and sex-related differences in nonfatal dog bite injuries among persons aged 0-19 treated in hospital emergency departments, United States, 2001-2017. Public Health Rep 2020;135(2):238–44.
8. Reuter Muñoz KD, Powell LE, Andersen ES, et al. Analysis of pediatric dog bite injuries at a level 1 trauma center over 10 years. Ann Plast Surg 2021;86(6S Suppl 5):S510–6.
9. Golinko MS, Arslanian B, Williams JK. Characteristics of 1616 consecutive dog bite injuries at a single institution. Clin Pediatr 2017;56(4):316–25.
10. Smith AM, Carlson J, Bartels AB, McLeod CB, Golinko MS. Characteristics of dog bites in Arkansas. South Med J 2018;111(8):494–500.
11. Daniels DM, Ritzi Rovane BS, O’Neil J, Tres Scherer LR. Analysis of nonfatal dog bites in children. J Trauma 2009;66(3):S17–22.
12. Kaye AE, Belz JM, Kirschner RE. Pediatric dog bite injuries: a 5-year review of the experience at the Children’s Hospital of Philadelphia. Plast Reconstr Surg 2009;124(2):551–8.
13. Bini JK, Cohn SM, Acosta SM, McFarland MJ, Muir MT, Michalek JE; for the TRISAT Clinical Trials Group. Mortality, mauling, and maiming by vicious dogs. Ann Surg 2011;253(4):791–7.
14. Bernardo LM, Gardner MJ, O’Connor J, Amon N. Dog bites in children treated in a pediatric emergency department. J Soc Pediatr Nurs 2000;5:87–95.
15. Reisner IR, Nance ML, Zeller JS, et al. Behavioural characteristics associated with dog bites to children presenting to an urban trauma centre. Inj Prev 2011;17:348–53.
16. Wu PS, Beres A, Tashjian DB, Moriarty KP. Primary repair of facial dog bite injuries in children. Pediatr Emerg Care 2011;27(9):801–3.
17. Ng ZY, Eberlin KR, Lin T, Masiakos PT, Cetrulo CL. Reconstruction of pediatric scalp avulsion injuries after dog bites. J Craniofac Surg 2017;28(5):1282–5.
18. Dickson L, Kattan A, Thoma A. Two-technique reconstruction following traumatic scalp avulsion: replantation and composite graft. Plast Reconstr Surg 2010;125(4):151e–2e.
19. Steiner D, Hubertus A, Arkudas A, et al. Scalp reconstruction: a 10-year retrospective study. J Craniomaxillofac Surg 2017;45(2):319–24.
20. Desai SC, Sand JP, Sharon JD, Branham G, Nussenbaum B. Scalp reconstruction: an algorithmic approach and systematic review. JAMA Facial Plast Surg 2015;17(1):56–66.
21. Miller GD, Anstee EJ, Snell JA. Successful replantation of an avulsed scalp by microvascular anastomoses. Plast Reconstr Surg 1976;58(2):133–6.
22. Yin JW, Matsuo JM, Hsieh CH, Yeh MC, Liao WC, Jeng SF. Replantation of total avulsed scalp with microsurgery: experience of eight cases and literature review. J Trauma 2008;64(3):796–802.
23. Zhang Y, Cheng K, Dong J, Li Q, Tremp M, Zhu L. Incidence and features of vertebral fractures after scalp avulsion injuries. J Craniofac Surg 2015;26(7):2217–20.
24. Isbester K, Wee C, Boas S, Sopko N, Kumar A. Regeneration of functional, full-thickness skin with minimal donor site contribution using autologous homologous skin construct. Plast Surg Case Stud 2020;1–4.
