A Skin-stretching Wound Closure System to Prevent and Manage Dehiscence of High-tension Flap Donor Sites: A Report of 2 Cases

Tension on the suture line of flap donor sites raises the risk of delayed healing and wound dehiscence. Closing a large flap donor site without a skin/flap graft is a major surgical challenge.    Recently, the authors started using a skin-stretching wound closure system designed to harness both mechanical creep and stress-relaxation principles for the management of a variety of surgically closed wounds, including flap donor sites. The system consists of a pair of attachment plates connected by a long, flexible approximation strap that can be invasively (sutured) or noninvasively (by adhesion) secured to the skin wound edges and gradually tightened. The care and outcomes of 2 of the 41 patients whose wounds were managed with this system at the authors’ plastic/reconstructive and wound repair center during a period of 7 months are described. The first case involved a 20-year-old patient with a 16 cm x 8 cm deep inferior epigastric perforator flap to reconstruct a malignant tumor resection of the groin. The second patient required a 10 cm x 8 cm anterolateral thigh free-flap to repair a traumatic dorsal skin, soft tissue defect. Wounds were assessed and tension adjusted every 2 or 3 days. Both lesions healed by primary intention and with a good cosmetic outcome. Controlled clinical studies are needed to examine the effectiveness, efficacy, indications, complications, and cost effectiveness of this closure system.

Tissue transfer has rapidly developed over the last half century to become a mainstay of reconstructive surgery. A reevaluation and reclassification of human anatomy has occurred, searching for possible donor tissue types from a variety of anatomical areas. This knowledge has been applied to best fulfill demands of the recipient site.¹ However, to date focus on the donor site in terms of either the potential for acute complications or long-term morbidity has been limited. Flap donor sites subjected to direct suture stress are at increased risk of delayed healing and dehiscence due to tension on the closure. The highest rate of dehiscence/rupture,  as reported in a review by Mahoney,¹ is 31%. According to personal opinion based on a case report, Addison et al² noted excessive wound tension increases the risk of wound dehiscence or delayed healing, unsightly scarring, and distal deep venous thrombosis. In a 2-center, retrospective review (N = 53), Shindo et al³ reported that, for the fibula osteocutaneous flap, major wound complications developed in 12% of patients who underwent primary closure.

Prevention and management of these defects poses a challenge for the reconstructive surgeon. Traditional management of these short-term complications involves skin grafts, local flaps, tissue stretching and expansion, and closure by secondary intention.¹ However, potential risks such as necrosis of the grafted/expanded skin also may leave large defects that cannot be primarily closed.⁴ In addition, these sites often may be aesthetically inferior to tensionless primary wound closure.⁵

In 2012, Topaz et al⁵ first reported their clinical experience with their TopClosure^® 3S System (I.V.T. Medical Ltd, Israel), an innovative, simple, skin stretching and wound closure system designed to harness both mechanical creep (a phenomenon where skin will stretch and elongate with time as long as force is applied) and stress relaxation principles. This tension release system (TRS) consists of a pair of attachment plates (APs) connected by a long, flexible approximation strap (AS) that can be invasively (sutured) or noninvasively (by adhesion) secured to the wound edge skin to close the wound by gradual tightening. Topaz et al shared their experiences of using these methods of skin stretching and elongation to secure the wound edges and improve scar aesthetics: the device was applied to 21 wounds in 20 patients 6 years and older for various clinical applications, including preoperative skin lesion removal, closure of a variety of surgical wounds, following trauma, and to secure the wound closure as noted in case 2 and case 4 of their study. Slow, gradual skin stretching was applied with minimal pull on the skin. Intermittent application of tension to the skin led to an incremental skin elongation through the stress-relaxation mechanism, facilitating closure of the wound.⁵ Their single-center case series of 3 representative patients indicated an acceptable outcome and validated use of the system.⁵ 

The Department of Plastic Surgery and Burn/Wound Center, Second Affiliated Hospital, College of Medicine, Zhejiang University, is one of the major plastic/reconstructive and wound repair centers in East China, annually treating approximately 2,500 inpatients and more than 12,000 outpatients with all different kinds of wounds. The TRS was first introduced in China in this health care facility. From September 2013 to March 2014, the TRS was used to close 43 different surgical wounds and protect the sutures in 41 Chinese patients (20 women and 21 men) with good results.

Closing a large flap donor site without a skin/flap graft is among the most challenging surgical tasks. Two typical cases treated at the wound center that involved donor site healing using the TRS are presented.

Case 1. Twenty-year-old Ms. Q was admitted for a 10 cm x 8 cm, partially necrotic and bleeding cutaneous tumor in her left groin (see Figure 1a). Before she came to the center, only 2 months had elapsed for her lesion to develop from a small eczema-like plaque to the present status. She had not received any previous treatment, had no other self-reported health conditions or comorbidities, and none were identified during presurgical health screening. Computer tomography (CT) scan indicated a solid, homogeneous tumor without involvement of the left femur artery, vein, or nerve (see Figure 1b). Biopsy result indicated small cell carcinoma. A multidisciplinary surgical team was assembled comprising an orthopedic oncology surgeon and a plastic and reconstructive surgeon. Before surgery, the patient’s ipsilateral and contralateral inferior epigastric arteries were located by noninvasive Doppler sensor, and a potential deep inferior epigastric perforator (DIEP) flap was designed to address the defect (see Figure 1c). Radical resection of the tumor then was completed, leaving a huge groin skin and soft tissue defect (see Figures 1d,e). A 16 cm x 8 cm contralateral DIEP flap was harvested and transferred to cover the wound (see Figures 1f–1h). The donor site margins were sutured, and 3 pair of APs were invasively placed along the suture line and interconnected by a long, flexible AS to relax the tension (see Figure 1i).

All of Ms. Q’s presurgical and postsurgical care was provided by the plastic surgeons and nurses at the center. After the operation, her gauze dressing was changed and the wound evaluated every 2 days. The suture line was disinfected with benzalkonium chloride and the sutures and adjacent skin assessed to evaluate the risk of rupture or skin trauma (ie, pressure ulcer) under the APs. The APs were carefully adjusted to gradually loosen the skin while protecting the sutures from excessive tension. At 4 weeks, Ms. Q’s wound was firmly closed and the sutures and APs were removed (see Figure 1j).

Because the pathology report indicated the lesion was a nonHodgkin’s lymphoma and positron emission tomography (PET) CT scan indicated several suspicious lymph nodes, Ms. Q was transferred to the Department of Hematology to receive chemotherapy.

Case 2. Mr. K is a 53-year-old man whose left foot and ankle were crushed in a traffic accident by the wheel of a heavy truck, causing a 10 cm x 8 cm skin and soft tissue avulsion on the ankle joint and dorsal site. Mr. K had no other self-reported health conditions or comorbidities; presurgical health screening indicated no other positive findings except for a smoking index of 600 (60 cigarettes per day times 10 years).

To cover this defect, right anterolateral thigh, free-flap transplantation was performed in the Orthopedic Wound and Fracture Department. Simultaneously, the donor site, too wide for primary closure, was covered with a split-thickness skin graft. However, both the grafted skin and the transplanted flap became necrotic, leaving a 10 cm x 16 cm defect on the right upper leg (see Figure 2a,b). The orthopedic surgeon took a cotton swab sample from the donor site defect wound for microbiological culture; the result indicated Serratia marcescens infection (sensitive to most antibiotics). Mr. K then was transferred to the wound center for treatment of both wounds by a plastic surgeon. After careful physical examination and discussion, the plastic surgeons decided to perform stress relaxation and assisted closure. This involved complete surgical debridement, followed by installation of 3 pair of APs, invasively placed along the wound axis and interconnected by a long, flexible AS (see Figure 2c). The wound was initially covered with Vaseline gauze (Jiujiang Huada Medical Dressing Co, Ltd, Gongqing City Jiangxi Province, P.R. China) (see Figure 2d). Simultaneously, for the foot and ankle wound, the necrotic grafted flap was removed, exposing thrombosis of the drainage vein (see Figure 2e). After debridement, another split-thickness skin graft was used to cover the left foot ankle wound (see Figure 2f). The plastic surgeons first changed the dressing 3 days after the surgery, using SeaSorb-Ag dressing (Coloplast Group, Humlebaek, Denmark) to cover the wound and absorb wound exudate; the dressing was changed every 2 days thereafter. During each dressing change, the wound and skin were assessed and wound measurements obtained, and the skin was gradually stretched by adjusting the AS. During this procedure, great care was taken (including daily check, adjusting AS, and placing soft gauze beneath the APs) to avoid inducing pressure ulcers beneath the APs (see Figure 2g). Nineteen (19) days after surgery, the residual wound measured 2 cm and was filled with granulation tissue that blocked the APs and skin (see Figure 2h). At a second surgery performed 19 days after the first, excess granulation tissue was resected and the wound was sutured closed (see Figure 2i). Another 2 pair of APs were placed to relax the tension (see Figure 2j). Fifteen (15) days later, both the suture and APs were removed. The muscle and fascia defect was firmly closed, leaving only several superficial skin gaps that healed with regular wound care, comprising daily dressing change, disinfection, and assessment (see Figure 2k); a skin graft was applied to the left foot ankle wound (see Figure 2l). At the 6-month follow-up, slight scarring at the donor site and foot wound was observed (see Figure 2m,n).

Donor site wound necrosis and dehiscence are among the most common early-stage complications after flap grafting. Risk for such complications is size-dependent: a larger flap will cause larger defect, and hence produce more tension for primary closing and lead to higher risk of dehiscence/rupture,⁶ which has been observed. The result of a recent meta-analysis by Salgarello et al⁶ that included 510 patients from 6 studies showed wound dehiscence and delayed wound healing in DIEP patients occurred at a rate of 7.2% (95% confidence interval [CI] = 4.1–12.4%). The key to preventing and managing these complications is control of the tension.

The TRS herein described was designed to either noninvasively or invasively harness the viscoelastic properties of the skin using mechanical creep and stress-relaxation principles. In the cases described, the mechanical creep properties of the skin were utilized by preoperative continuous skin stretching; the method has been applied in cases of unhealed ulcers, skin tumors, scars, and birth marks — ie, lesions needing plastic removal and reconstruction. Such a system also can provide acute skin stretching by stress relaxation through intraoperative, invasive, cyclical skin elongation and for postoperative invasive or noninvasive scar tension release to secure wound closure.⁵

The 2 cases reported demonstrated the viscoelastic properties of the TRS. In the first case, continuous stress relaxation was used because of the risk of wound dehiscence in this patient. In a case report⁷ of 1 patient, skin stretching was shown to allow a gradual decrease in the tension of the wound closing over time, allowing primary closure of relatively large defects. In the second case, slow, gradual skin stretching was applied by minimal pull on the skin every 2 days post surgery. Intermittent application of tension to the skin led to an incremental skin elongation through the stress relaxation mechanism, facilitating the wound closure.⁸ The TRS enabled a selective distribution of a minimal load on the injured skin edges according to the specific clinical condition. An advantage of using a technique to facilitate primary closure is the closed wound may have a much smaller scar when compared with split-thickness skin graft⁵; hence, the result preserves the aesthetic and functional properties of the skin (eg, sweating, sensitivity) better than in grafted skin.

According to the system’s inventors (Topaz et al⁵), applying the TRS has a notable advantage: the ability to apply presurgical mechanical creep through external skin stretching (for low tension wound closure) and postoperative acute intraoperative stress relaxation (for high tension wound closure). Undermining skin edges and adjacent tissues can be avoided, maintaining adequate blood supply to the wound margins and securing the viability of the skin edges even under extreme tension. Avoidance of undermining eliminates dead space and reduces the risk of seroma and hematoma accumulation; it also removes the need for drainage and reduces the risk of infection.⁵ Skin can be further approximated following stress relaxation by advancing the AS as a bedside procedure by using mechanical creep, in some cases under local anesthesia.

In the authors’ experience, when used as a topical tension-relief platform for tension sutures, TRS alleviates the frequently observed tearing and scarring inflicted by tension sutures. Because of its simplicity, TRS can be used for a wide scope of indications in a wide range of surgical settings.⁹ The authors of the current study also appreciated the fact that the TRS design facilitated better daily assessment and adjustment compared with a planted inner balloon expander that is another option.

The ability to draw conclusions from this and other case studies is limited. At this time, evidence about the effectiveness and efficacy of TRS is incomplete. These case study results are encouraging and similar to those reported in the literature.⁵ Multicenter, cohort studies comparing wound and patient outcomes of TRS management and other donor site management methods are needed to help clinicians make evidence-based donor site closure decisions.

In this case study, the TRS was successfully applied to gradually stretch skin and soft tissues involved in large defect flap donor sites and facilitate primary closure without overwhelming tension. Moreover, TRS protected the primary suture lines from tensions risk for rupture.

This is the second report worldwide and the first in China to describe the clinical application of the TRS. A large-scale, randomized, controlled study to examine the effectiveness, efficacy, indications, complications, and cost effectiveness of this closure system is warranted.

Dr. Dan is an attending physician, Department of Plastic Surgery, Second Affiliated Hospital, College of Medicine, Zhejiang University, Hang Zhou, P.R. China.
Dr. Hongfei is a resident, Assisted Reproduction Unit, Department of Obstetrics and Gynecology, Sir Run Run Shaw Hospital, College of Medicine, Zhejiang
University, Hangzhou, China. Dr. Huahui is a resident, Department of Plastic Surgery, Second Affiliated Hospital, College of Medicine, Zhejiang University.
Dr. Chunmao is a resident; and Dr. Hang is an attending physician, Department of Burns and Wound Center, Second Affiliated Hospital, College of Medicine,
Zhejiang University. Please address correspondence to: Hu Hang, MD, PhD, Department of Burns and Wound Center, Second Affiliated Hospital, College of
Medicine, Zhejiang University, 88# JieFang Road, Hangzhou, Zhejiang Province, 310009, PR China; email: huhangbob@aliyun.com.