Our Experience with Wisebands: A New Skin and Soft-Tissue Stretch Device

A novel tension relief technique to aid the primary closure of traumatic equine wounds under excessive tension

BACKGROUND

To achieve an excellent functional and cosmetic result, primary closure is preferred over leaving wounds to heal by secondary intention. However, traumatic wounds are often under excessive tension during wound closure and incorrect suture technique can compromise microcirculation, leading to skin necrosis and impaired wound healing.

OBJECTIVE

To describe an inexpensive and effective tension relief technique that helps the successful primary closure of a variety of equine wounds at high risk of dehiscence.

STUDY DESIGN

Retrospective case series.

METHODS

All wounds that were managed with the Tension Tile System (TTS) at four Equine Hospitals between March 2017 and May 2021 were evaluated. The wounds were classified according to various criteria including anatomical location, time elapsed prior to surgery, depth of wound and post-surgical use of immobilisation. Outcome criteria were based on the success of primary intention healing. The duration of convalescence (weeks) after surgery was also recorded.

RESULTS

During the study period, the TTS was used in 191/860 (22%) wounds repaired under general anaesthesia or standing sedation. Overall, primary intention healing (Group A) was achieved in 132 of 191 cases (69%, CI 62%-75%), with partial dehiscence (Group B) in a further 30/191 cases (16%, CI 11%-22%). Severe dehiscence (Group C) was recorded in 29/191 cases (15%, CI 11%-21%). The median convalescence time was 4 weeks (Range 3-15, interquartile range 4-6) in Group A.

MAIN LIMITATIONS

Retrospective nature of the study and subjective outcome assessment. The technique was applied to wounds under significant tension; however, this was based on a subjective assessment by the surgeons involved.

CONCLUSIONS

The Tension Tile System is an economical and effective technique for challenging equine wounds under tension, in a variety of anatomical locations.

What are optimum cycles for immediate primary closure of large cutaneous defects?

BACKGROUND

In the reconstruction of large complex cutaneous wounds, a myriad of mechanical devices has been designed to facilitate primary wound closure. However, there is a dearth of studies elucidating how best to achieve optimum use and efficiency of skin stretching (SS) when using the device for immediate primary closure of defects.

METHODS

Skin defect wounds (7 × 7 cm) were prepared on the back of three Bama miniature pigs. A total of 15 cycles of SS (cycle loading) were subsequently performed on the skin edges of the wound by EASApprox® SS system. Then, the changes in equidistant points were recorded after each cycle. After the SS test, all wounds were sutured under low tension.

RESULTS

Skin elongation was observed at all equidistant points on the back wounds of three Bama miniature pigs. Up to an additional 1.10 to 3.75 cm of tissue was garnered. The maximum skin elongation was typically achieved within eight cycles of stretching and relaxation. Beyond this range, additional stretching cycles did not result in further skin extension.

CONCLUSION

There may be a close link between mobilization range and the times of acute cyclic stretching (cycle loading) during the process of primary wound closure. However, larger studies are required to further evaluate the accuracy and effectiveness.

The History of Plastic Surgery in Israel

Today, plastic surgery is a well-known profession with highly respected surgeons from institutions all over the world. Over the last several decades numerous clinical and technological advances have been made, thanks to the dedication and hard work of these outstanding professionals; however, things were not always this way. At the turn of the 20th century, Israel had yet to be introduced to the field of plastic surgery. However, this all changed with the War of Independence. Humanitarian aid by the prominent South African surgeon, Jack Penn, laid the foundation for the founding fathers of plastic surgery in Israel to establish a strong legacy of producing world-renowned surgeons and innovators. Through this paper, we hope to provide a brief overview of the history of plastic surgery in Israel and what transpired to give us the state of surgical practice we have today.

Israeli Innovations in the Field of Plastic Surgery

Numerous innovations within the field of plastic surgery have been developed in Israel over the last few decades. Many of these therapeutic devices and techniques have been established globally with demonstrable efficacy and respectable safety profiles. This article offers an overview of recent Israeli cutting-edge medical therapeutic solutions contributing to the global practice of plastic surgery.

Efficacy and safety of external tissue expansion technique in the treatment of soft tissue defects: a systematic review and meta-analysis of outcomes and complication rates

Background

Currently, various external tissue expansion devices are becoming widely used. Considering the scarcity of relevant application standards, this systematic review was performed to explore the effectiveness and safety of external tissue expansion techniques for the reconstruction of soft tissue defects.

Method

A systematic review and meta-analysis on the efficacy and safety of external tissue expansion technique was conducted. A comprehensive search was performed in the following electronic databases: PubMed/Medline, Embase, Cochrane Library (Wiley Online Library), and Web of Science. Studies reporting patients with soft tissue defects under the treatment of external tissue expansion technique were included.

Results

A total of 66 studies with 22 different types of external tissue expansion devices met the inclusion criteria. We performed a descriptive analysis of different kinds of devices. A single-arm meta-analysis was performed to evaluate the efficacy and safety of the external tissue expansion technique for different aetiologies. The pooled mean wound healing time among patients with defects after fasciotomy was 10.548 days [95% confidence interval (CI) = 5.796–15.299]. The pooled median wound healing times of patients with defects after excisional surgery, trauma, chronic ulcers and abdominal defects were 11.218 days (95% CI = 6.183-16.253), 11.561 days (95% CI = 7.062-16.060), 15.956 days (95% CI = 11.916-19.996) and 12.853 days (95% CI=9.444-16.227), respectively. The pooled wound healing rates of patients with defects after fasciotomy, excisional surgery, trauma, chronic ulcers and abdominal defects were 93.8% (95% CI=87.1-98.2%), 97.2% (95%CI=92.2-99.7%), 97.0% (95%CI=91.2-99.8%), 99.5% (95%CI=97.6-100%), and 96.8% (95%CI=79.2-100%), respectively. We performed a subgroup analysis in patients with diabetic ulcers and open abdominal wounds. The pooled median wound healing time of patients with diabetic ulcers was 11.730 days (95% CI = 10.334-13.125). The pooled median wound healing time of patients with open abdomen defects was 48.810 days (95% CI = 35.557–62.063) and the pooled successful healing rate was 68.8% (95% CI = 45.9-88.1%). A total of 1686 patients were included, 265 (15.7%) of whom experienced complications. The most common complication was dehiscence (n = 53, 3.14%).

Conclusions

Our systematic review is the first to demonstrate the efficacy and safety of external tissue expansion in the management of soft tissue defects. However, we must interpret the meta-analysis results with caution considering the limitations of this review. Large-scale randomized controlled trials and long-term follow-up studies are still needed to confirm the effectiveness and evaluate the quality of healing.

Closure of Complex Wounds by a Simple Skin Stretching System Associated With Vacuum Sealing Drainage-Clinical Outcome of 34 Patients

Management of complex wounds with large skin defects presents a real challenge for orthopedic or reconstructive surgeons. We developed a simple skin stretching system associated with vacuum sealing drainage to examine the efficiency and complication. A total of 34 patients with different types of complex wounds were retrospectively included from January 2015 to March 2021. All patients in the study were underwent the treatment by 2 stages. The method was used to the wounds from 4.71 to 169.65 cm² with a median defect size of 25.13 cm². The median time for wound closure was 11.5 days (range: 5-32 days), although the median absolute reduction was 2.08 cm²/day (range: 0.15-25.66 cm²/day). Depending on the site of the wounds, the cause of the wound, and the rate of max-width/max-length (W/L), these complex wounds could be separately divided into several groups. There were statistically significant differences in the median value of the above variables (P < .05 Kruskal-Wallis test). The results showed that different anatomical sites had different viscoelastic properties, the complex wounds caused by trauma were easier to close than caused by diabetic foot and the complex wounds in group A (W/L ＞ 0.5) were more difficult to close than in group B (W/L ≤ 0.5). No major complications were encountered in this study. In summary, the results of our study showed that the simple skin stretching system associated with vacuum sealing drainage was a safe approach for closure of complex wounds. Nevertheless, more attention should be paid to the viscoelasticity of the wounds to ensure closure and avoid undue complications when applying the method.

Application of a simple skin stretching system and negative pressure wound therapy in repair of complex diabetic foot wounds

The management of complex diabetic foot wounds with large skin defects poses a challenge for surgeons. We presented a simple skin stretching system and negative pressure wound therapy for the repair of complex diabetic foot wounds to examine the effectiveness and safety.

A total of 16 patients with diabetic foot ulcers were retrospectively reviewed between January 2015 and October 2020. All patients underwent the treatment by 3 stages. In stage 2, these difficult-to-close wounds of diabetes foot were residual. This method was applied to the wounds with a median defect size of 20.42 cm² (range, 4.71–66.76 cm²).

The median time for closure of complex diabetic foot wounds was 14 days ranging from 8 to 19 days. With respect to the absolute rates of reduction, it was observed with a median of 1.86 cm²/day, ranging from 0.29 cm²/day to 8.35 cm²/day. In accordance with the localization of the defect, the patients were divided into 3 groups: side of the foot (37.5%), dorsum of the foot (50.0%), and others (12.5%). There was no statistical difference between side of the foot and dorsum of the foot in terms of the median defect size with P = 0.069 (Kruskal–Wallis test). Otherwise, there were statistically significant differences regarding the median time and the median absolute rates (P < 0.05; Kruskal–Wallis test). No severe complications were encountered in this study.

In summary, our results show that application of the simple skin stretching system and NPWT is an effective and safe approach to complex diabetic foot wounds. Nevertheless, more attention should be paid to the appropriate patient selection and intraoperative judgment to ensure wound closure and avoid undue complications.

A novel skin-stretching device for closing large skin-soft tissue defects after soft tissue sarcoma resection

BACKGROUND

Closure of large skin-soft tissue defects following soft tissue sarcoma (STS) resection has been a great challenge. The objective of this study was to evaluate the effectiveness of a novel, simple, and cheap skin-stretching device (bidirectional regulation-hook skin closure system, BHS) for closing large skin-soft tissue defects resulting from the removal of STS and the complications associated with the use of the BHS.

METHODS

From January 2017 to September 2018, 25 patients with STS underwent BHS therapy after tumor resection. BHS was used for two main clinical applications: securing wound closure after high-tension suture closure and delayed wound closure. We described a detailed reconstruction procedure regarding this therapy. Wound closure and complications associated with BHS therapy were recorded. We also analyzed tumor recurrence and metastases.

RESULTS

All patients were observed for 16-36 months with an average follow-up of 25.6 months. During the follow-up period, no significant functional restriction was observed and the final scar was aesthetically acceptable. Superficial wound infection occurred in six patients, wound edge ischemia in two patients, and small skin tears in two patients. Two patients developed pulmonary metastasis, two patients had a local recurrence, and one patient died of pulmonary metastasis.

CONCLUSIONS

BHS therapy can effectively close large skin-soft tissue defects following STS resection and obtain acceptable functional results, without severe complications. However, larger studies are required to further evaluate the effectiveness, indications, and complications of BHS therapy.

The Use of Self-Inflating Hygroscopic Tissue Expanders to Facilitate Osteosarcoma Removal in a Massasauga Rattlesnake (Sistrurus catenatus)

A 0.34 kg adult female Massasauga rattlesnake (Sistrurus catenatus) was presented for evaluation of a subcutaneous mass affecting the ventral scales. The mass was diagnosed as a sarcoma via punch biopsy with no evidence of metastasis on diagnostic imaging. Surgical margins of 1-2 cm were planned to achieve complete excision of the neoplasm. A technique for tissue expansion was employed due to concerns regarding the ability to close the surgical site without excess tension or dehiscence. Two 27 mm diameter × 5 mm hygroscopic self-inflating tissue expanders were placed subcutaneously under the lateral scales adjacent to the mass. Maximum skin expansion occurred over a four-week period, and no direct negative effects were noted. Excision of the primary mass was performed routinely five weeks after implant placement. Primary closure of the defect was achieved with minimal tension by incorporating the expanded skin. While the surgery was successful with no evidence of metastasis, the snake died of sepsis two weeks postoperatively. This is the first report of the use of self-inflating hygroscopic tissue expanders to help close a surgical defect in a reptile.

Therapeutic advances in wound healing

Wound healing is a complex physiological process that occurs in the human body involving the sequential activation of multiple cell types and signaling pathways in a coordinated manner. Chronic wounds and burns clearly decrease quality of life of the patients since they are associated with an increase in physical pain and socio-economical complications. Furthermore, incidence and prevalence of chronic wounds (unlike burns) have been increasing mainly due to population aging resulting in increased costs for national health systems. Thus, the development of new and more cost-effective technologies/therapies is not only of huge interest but also necessary to improve the long-term sustainability of national health systems. This review covers the current knowledge on recent technologies/therapies for skin regeneration, such as: wound dressings; skin substitutes; exogenous growth factor based therapy and systemic therapy; external tissue expanders; negative pressure; oxygen; shock wave, and photobiomodulation wound therapies. Associated benefits and risks as well as the clinical use and availability are all addressed for each therapy. Moreover, future trends in wound care including novel formulations using metallic nanoparticles and topical insulin are herein presented. These novel formulations have shown to be promising therapeutic options in the near future that may change the wound care paradigm.

Primary Closure of Wide Fasciotomy and Surgical Wounds Using Rubber Band-Assisted External Tissue Expansion: A Simple, Safe, and Cost-effective Technique

BACKGROUND

Although decompressive fasciotomy is a limb-saving procedure in the setting of acute compartment syndrome, it leaves a large wound defect with tissue edema and skin retraction that can preclude primary closure. Numerous techniques have been described to address the challenge of closing fasciotomy wounds. This study reports our experience with fasciotomy closure using rubber bands (RBs) for external tissue expansion.

METHODS

Patients were informed about RB closure and split-thickness skin graft options. Only patients who opted for RB closure and had wounds that could not be approximated using the pinch test underwent the procedure. Starting from the apex and progressively advancing, the RBs were applied to the skin edges at 3 to 4 mm intervals using staples. The RBs were advanced by twisting back-and-forth to create a criss-cross pattern. One week after application, fasciotomy wounds were closed primarily or underwent further RB application, based on clinical assessment of adequacy of skin advancement, compartment tension, and perfusion. Review of a prospectively maintained database was performed, including demographics, comorbidities, etiology, wound and operative details, hospital stay, and complications.

RESULTS

Seventeen consecutive patients with 25 wounds (22 fasciotomy and 3 other surgical wounds) were treated using the RB technique. Average wound length and width measured 15.7 cm (range, 5-32 cm) and 5.2 cm (range, 1-12 cm), respectively. Locations of wounds included forearm (n = 12, 48.0%), leg (n = 7, 28.0%), hand (n = 4, 16.0%), elbow (n = 1, 4.0%), and hip (n = 1, 4.0%). Eighteen of 25 wounds (72.0%) were closed primarily after 1 RB application. Additional RB application was required for 5 wounds to achieve primary closure. Between stages, patients were discharged home if they did not have other conditions requiring in-hospital stay. No complications were observed, and no revision surgeries were required. Patient satisfaction was 100%, and all indicated that they would choose the RB technique over skin grafting.

CONCLUSIONS

The modified RB technique is a simple, safe, and cost-effective alternative for treating fasciotomy and other surgical defects resulting in high patient satisfaction and good cosmetic outcome, without the need for split-thickness skin graft or flap coverage.

EASApprox® skin-stretching system: A secure and effective method to achieve wound closure

Large skin defects are commonly observed in the clinic and have attracted much attention recently. Therefore, finding an effective solution for large skin defects is a global problem. The objective of the present study was to assess the effectiveness of the EASApprox^® skin-stretching system for closing large skin defects. Skin defects (5×5 cm) were created on the forearms of 9 Bama miniature pigs, which were randomly divided into the following three groups: Direct suture, the new EASApprox^® skin-stretching device and Kirschner wires. Microcirculation was assessed before surgery and after wound closure. Following the different treatments, the defects were sutured, and wound healing was assessed based on a clinical score. Furthermore, microscopic and ultramicroscopic structures were evaluated, including collagen, elastic fibers and the microvessel density. Significant differences in the clinical score and microvessel density were observed among the groups. Additionally, the mean length obtained for elastic fibers was larger than that obtained for the other two groups. Finally, the new EASApprox^® skin-stretching device resulted in successful wound management and with only minor side effects on skin histology and microcirculation. Therefore, this method has the potential to be used for healing large skin defects.

Stress-relaxation and tension relief system for immediate primary closure of large and huge soft tissue defects: an old-new concept: new concept for direct closure of large defects

Stress-relaxation is a well-established mechanism for laboratory skin stretching, with limited clinical application in conventional suturing techniques due to the inherent, concomitant induction of ischemia, necrosis and subsequent suture failure. Skin defects that cannot be primarily closed are a common difficulty during reconstructive surgery. The TopClosure tension-relief system (TRS) is a novel device for wound closure closure, providing secured attachment to the skin through a wide area of attachment, in an adjustable manner, enabling primary closure of medium to large skin defects. The aim of this study was to evaluate the efficiency of the TopClosure TRS as a substitute for skin grafting and flaps for primary closure of large soft tissue defects by stress-relaxation. We present three demonstrative cases requiring resection of large to huge tumors customarily requiring closure by skin graft or flaps. TRS was applied during surgery serving as a tension-relief platform for tension sutures, to enable primary skin-defect closure by cycling of stress-relaxation, and following surgery as skin-secure system until complete wound closure. All skin defects ranging from 7 to 26 cm in width were manipulated by the TRS through stress-relaxation, without undermining of skin, enabling primary skin closure and eliminating the need for skin grafts and flaps. Immediate wound closure ranged 26 to 135 min. TRS was applied for 3 to 4 weeks. Complications were minimal and donor site morbidity was eliminated. Surgical time, hospital stay and costs were reduced and wound aesthetics were improved. In this case series we present a novel technology that enables the utilization of the viscoelastic properties of the skin to an extreme level, extending the limits of primary wound closure by the stress-relaxation principle. This is achieved via a simple device application that may aid immediate primary wound closure and downgrade the complexity of surgical procedures for a wide range of applications on a global scale.

Comparison of three skin-stretching devices for closing skin defects on the limbs of dogs

Our objective was to evaluate the effectiveness of skin-stretching devices for closing defects on the extremities of dogs. Antebrachial skin defects were created on the limbs of 24 dogs randomly divided into three groups. Skin stretchers included staples and sutures passing through them (group A), sutures and hypodermic needles (group B), and Pavletic device (group C). Wounds on the left were further undermined in all groups. Tension and blood perfusion were assessed. After removing the stretchers on day 3, the defects were sutured and wound healing was clinically scored. Histological variables evaluated were cellular infiltration, edema, collagen orientation, and thickness of epidermis. Significant differences in tension were found among groups (p < 0.0005) and between measurement times for undermined (p = 0.001) or non-undermined (p < 0.0005) wounds. In contrast, blood perfusion values did not differ significantly. Clinical scores for group B seemed to be better than those for groups A and C, but differences were not significant. Primary wound closure using the Pavletic device was not feasible. No significant differences in histological variables were found between groups. Skin stretching with staples or hypodermic needles resulted in successful wound management with minor side effects on skin histology and circulation.

Reverse tissue expansion by liposuction deflation for revision of post-surgical thigh scars

Scars hypertrophy and widen when stretching mechanical forces are applied to resilient newly formed collagen before it reaches final maturity marring the final result of many surgical procedures and resulting in a clinical problem for many patients. Scar revision by surgical excision remains the traditional treatment for hypertrophic or widespread scars. It relies upon recruitment of local tissues for closure of the ensuing defect. Providing tension-free skin closure is the best option to avoid recurrence. Although tissue expansion procedure is a valuable and reliable technique for scar revision, it has its own disadvantages and potential complications. We describe an alternative method for scar revision that may be applicable in certain situations. Instead of expanding the soft tissues to make available additional skin, deflation by liposuction may be affected to relax the skin envelope thus indirectly providing additional skin for scar revision. We call this method 'reverse tissue expansion'.

A simple solution for wound coverage by skin stretching

Viscoelastic properties of skin, ie, creep and stress relaxation, allow it to stretch beyond its normal state within a short period of time. Presented here is a technique of "wound coverage by skin stretching" that uses this principle. Kirschner wires were passed through the skin edges on either side of the wound margins. Dynamic traction was applied with traction bands improvised by the surgeon from surgical glove wrist rings. We used this method in eight patients to close 10 wounds that were not feasible to close with direct methods. We have found that this simple, economic, and effective method provides rapid functional wound closure when bone and other structures are exposed. It does not require specialized training or devices. Careful attention to the described surgical technique gives good results and few complications.

[Optimized negative pressure therapy. Case report]

Our patient showed major abdominal cutaneous necrosis. Detersion removed the entire thickness of half of the right-hand wall of the abdomen. We are going to explain how, by combining well known procedures, we conducted this closure. This deals with a patient aged 53, with a long case history of dermatomyositis and highly debilitating sub-cutaneous calcinosis. This patient has been treated with Imurel and high doses of corticoids since 1997. In the face of the much debilitated terrain of the patient, it was not certain that a local flap or even a pediculated flap could be made to cover this loss of substance with a minimum of risk. A cutaneous extension was then envisaged using a system of Wisebands fillets. To protect the parietal plate, accelerate its growth and reduce the skin tension, we used in combination a system of foam dressing with negative pressure therapy (NPT). The optimized NPT was used for 2 weeks. The Wisebands were installed for 1 month. The treatment lasted for 50 days and required five short sessions of general anaesthesia. The histopathological interpretation revealed an EBV lymphoma. The assessment of the extension and the therapeutic treatment of the lymphoma contributed to the duration of hospitalisation and the number of general anaesthesia sessions. The synergy effect of these two associated procedures have allowed a faster skin closure; 18 months later, no complications have occurred. The wound has closed totally and the abdominal wall is solid in spite of not having resorted to a flap or separation.

Closing fasciotomy wounds using plastic bands: an alternative simple and cheap method

Fasciotomy incisions are essential to relieve pressure on the neurovascular structures in the limbs. However, closing such wounds often becomes a challenge to the surgeon. The aim of this study is to describe a simple and cheap method of closing these wounds. Plastic bands were used to gradually close fasciotomy wounds in five patients. All fasciotomy wounds in the five patients closed successfully within 4-12 days. Only two patients developed minimal complications in the form of minor wound infection and a hypertrophic scar. We conclude that the plastic band method used here is cheaper and simpler in comparison to similar techniques using the same device.

Delayed primary closure of fasciotomy wounds with Wisebands, a skin- and soft tissue-stretch device

BACKGROUND

Fasciotomy incisions for limb compartment syndrome usually cannot be closed primarily. The conventional method of wound closure with split-thickness skin grafting is effective, but it results in an insensate and disfiguring wound and is associated with donor site morbidity. We present our experience in delayed primary closure of fasciotomy wounds with Wisebands (WB), a skin- and soft tissue-stretching device.

PATIENTS

Between 2000 and 2003, we treated 16 patients with extremity fasciotomy wounds for which primary closure was not feasible.

RESULTS

The Wisebands devices achieved controlled stretching of the wound edges, including skin and underlying soft tissue, until primary closure was feasible. Fourteen patients (88%) had successful wound closure, two patients (12%) had minor wound complications that did not necessitate the removal of the device, and two patients had local wound complications (infection, intractable pain) and their devices were removed prematurely. Delayed primary closure was achieved at the initial surgery using intraoperative skin stretching in 3 of the 14 cases (21%). After a 2-year follow-up (1.3-4 years), the treated area showed stable scarring with good aesthetic outcome and no functional deficit.

CONCLUSIONS

The Wisebands device facilitates closure of fasciotomy wounds with low complication rates and good functional and aesthetic outcome. Its application is simple and safe and requires a short learning curve. Nevertheless, appropriate patient selection, intraoperative judgment and close postoperative supervision are essential for optimal results.

Long-Term Results of Wounds Closed under a Significant Amount of Tension

BACKGROUND

The authors present the long-term follow-up of scars on various locations up to 7 years postoperatively, after closure of large skin defects with the use of a skin-stretching device.

METHODS

In a prospective, nonrandomized study of 30 patients whose initial wound could not be closed primarily without using a significant amount of tension, a complete follow-up of 24 cases was possible. Patients were observed preoperatively, postoperatively, and at long-term follow-up (mean, 7 years) for wound control and scar evaluation.

RESULTS

In 28 cases (93 percent), successful closure of a large defect was achieved. In the other two cases, a split-thickness skin graft was needed for wound closure. With respect to long-term scar formation after 7 years (24 cases), scarring was observed mainly on the scalp (average, 56 percent), back (average, 52 percent), and shoulder (average, 53 percent). On the extremities, including thigh and groin, there was significantly less scarring (p = 0.0004; average, 10 percent). Three weeks after the operation, 23 percent of the total scar formation had already occurred, whereas 57 percent occurred by 3 months postoperatively and 83 percent occurred by 6 months postoperatively.

CONCLUSION

This study demonstrates the considerable difference in scar formation among scalp, back, and shoulder defects compared with those on the extremities, groin, and thigh.