The availability of perifascial areolar tissue graft for deep cutaneous ulcer coverage

Perifascial areolar tissue graft promotes angiogenesis and wound healing in an exposed ischemic component rabbit model

Multiple studies have reported the use of perifascial areolar tissue (PAT) grafts to treat wounds involving exposed ischemic tissues, avascular structures, and defective membrane structures. Our objective was to assess the quantitative effects of PAT grafts and their suitability for wounds with ischemic tissue exposure and to qualitatively determine the factors through which PAT promotes wound healing and repair. We conducted histological, immunohistochemical, and mass spectrometric analyses of the PAT grafts. PAT grafts contain numerous CD34+ progenitor/stem cells, extracellular matrix, growth factors, and cytokines that promote wound healing and angiogenesis. Furthermore, we established a male rabbit model to compare the efficacy of PAT grafting with that of an occlusive dressing treatment (control) for wounds with cartilage exposure. PAT grafts could cover ischemic components with granulation tissue and promote angiogenesis. Macroscopic and histological observations of the PAT graft on postoperative day seven revealed capillaries bridging the ischemic tissue (vascular bridging). Additionally, the PAT graft suppressed wound contraction and alpha smooth muscle actin (αSMA) levels and promoted epithelialization. These findings suggested that PAT can serve as a platform to enhance wound healing and promote angiogenesis. This is the first study to quantify the therapeutic efficacy of PAT grafts, revealing their high value for the treatment of wounds involving exposed ischemic structures. The effectiveness of PAT grafts can be attributed to two primary factors: vascular bridging and the provision of three essential elements (progenitor/stem cells, extracellular matrix molecules, and growth factors/cytokines). Moreover, PAT grafts may be used as transplant materials to mitigate excessive wound contraction and the development of hypertrophic scarring.

Mini-Review: Tendon-Exposed Wound Treatments

BACKGROUND

Tendon-exposed wounds are complex injuries with challenging reconstructions and no unified treatment mode. Furthermore, insufficient tissue volume and blood circulation disorders affect healing, which increases pain for the patient and affects their families and caretakers.

REVIEW

As modern medicine advances, considerable progress has been made in understanding and treating tendon-exposed wounds, and current research encompasses both macro-and micro-studies. Additionally, new treatment methods have emerged alongside the classic surgical methods, such as new dressing therapies, vacuum sealing drainage combination therapy, platelet-rich plasma therapy, and live-cell bioengineering.

CONCLUSIONS

This review summarizes the latest treatment methods for tendon-exposed wounds to provide ideas and improve their treatment.

Utilization of Perifascial Loose Areolar Tissue Grafting as an Autologous Dermal Substitute in Extremity Burns

BACKGROUND

Perifascial areolar tissue (PAT) is an areolar layer over the muscle fascia. PAT has been shown to be resistant to ischemia and prone to survival even in ischemic conditions. PAT grafts provide a vascular tissue layer on necrotic bone and tendons where skin grafting is not possible. The effect of PAT grafting on burn reconstruction has not yet been reported. Thus, in this study, we aimed to present our experience and discuss the role of PAT grafting in extremity burn reconstruction.

METHODS

Between January 2019 and December 2020, 16 PAT grafting procedures were performed in 11 patients. All patients had second- or third-degree burns in the upper and lower extremities, with exposed bone or tendon. PAT grafts were harvested from the abdominal region and were used for the upper extremity in 7 patients and the lower extremity in 4 patients. Immediate skin grafting was performed during the same session.

RESULTS

The patients' mean age was 50.7 years; defect size, 3.3 × 3 cm²; and follow-up time, 11.8 months. The survival rates of the PAT and skin grafts were 93.8% and 68.6%, respectively. Partial skin graft losses were encountered in 4 patients, and total skin graft loss was seen in 1 patient.

CONCLUSION

PAT grafting is an alternative method to the use of dermal substitutes and flap surgery in small-to-medium-sized defects with exposed bone and tendon in burn patients.

Perifascial Areolar Tissue Transplantation for Covering Exposed Proximal Interphalangeal Joint After Electric Burn

Soft tissue damage in electric burn injuries is often deep and may expose tendons, bones, or joints in the hand. Here, we present the case of a 76-year-old man treated using perifascial areolar tissue (PAT) transplantation for covering the proximal interphalangeal joint of the middle finger, which had been exposed because of an electric burn. Following ointment therapy, surgery was performed on day 34 postinjury when a deep ulcer with opening of the proximal interphalangeal joint was observed on the dorsum of the right middle finger. After resecting the cartilage of the proximal interphalangeal articular surface, two Kirschner wires were inserted, and arthrodesis was performed. PAT was harvested from the left inguinal region and applied to the joint exposed wound of the middle finger. Full-thickness skin graft was applied over it. Three months after surgery, the preserved middle finger could be used as a functional finger. PAT transplantation does not require microsurgery techniques, is simple and minimally invasive, and has a short treatment period, so it may be an effective option for treating wounds in which exposed ischemic tissue is present. Soft tissue damage in electric burn injuries is often deep and may expose tendons, bones, and joints in the hand, which is the most common affected site. Here, we report a case treated using perifascial areolar tissue (PAT) transplantation for covering the proximal interphalangeal joint of the middle finger, which had been exposed because of an electric burn.

Use of Triceps Tendon and Paratenon Composite Graft for Extensor Tendon Reconstruction in the Hand: A Case Report

An extensor tendon defect in the hand requires reconstruction to restore extension. We report a 44-year-old woman with a 24-mm extensor tendon defect of the middle finger over the dorsum of the hand that was reconstructed using a composite graft consisting of the triceps tendon and paratenon. This composite graft from the posterior aspect of the distal arm is simple, safe and may be considered in extensor tendon reconstruction. Level of Evidence: Level V (Therapeutic).

A Novel Model of Perifascial Areolar Tissue Transplant in Rats

Background Perifascial areolar tissue (PAT) transplant is a method of transplanting loose connective tissue harvested in a sheet form from above the fascia to the wound bed and is effective for wounds with exposed ischemic tissue. However, the engraftment mechanism is unknown, and no animal models of PAT transplant for wound healing exist.

Methods In this study, we harvested connective tissue from the backs of Wistar rats in a sheet form to simulate a human PAT transplant. The PAT was affixed to exposed bone of the head.

Results In the PAT(+) group, the wound areas gradually decreased due to epithelialization and contraction. The wound area of the PAT(+) group was significantly smaller than that of the PAT(−) group.

Conclusions This clinically relevant rat model is useful for elucidating the mechanism of the PAT transplant and establishing a reliable surgical method.

Exposed Artificial Plate Covered With Perifascial Areolar Tissue as a Nonvascularized Graft

Perifascial areolar tissue (PAT) is a loose connective tissue on deep fascia, such as on the groin, thigh, or temporal region, which has abundant vascular plexus and mesenchymal stem cells. Nonvascularized PAT grafts can survive even on hypovascular wound beds. Therefore, PAT grafting is a possible alternative to conventional flap surgery to cover exposed bone or artifacts. In this article, we describe 2 cases of PAT grafting for the treatment of skin ulcers with exposed bone and artificial plate after mandible reconstruction. After negative-pressure wound therapy, PAT was used to covering exposed artificial plate for both cases, and a skin graft onto the PAT graft was performed in 1 case. The ulcers improved in both cases without recurrence. The gold-standard treatment of intractable ulcers and fistulas with an exposed tendon, bone, or artifact is coverage by a well-vascularized skin flap. However, PAT grafting has advantages in similar situations, occasionally together with skin grafting and/or negative-pressure wound therapy, because it is technically simple and less invasive.

A Perifascial Areolar Tissue Graft With Topical Administration of Basic Fibroblast Growth Factor for Treatment of Complex Wounds With Exposed Tendons and/or Bones

The management of wounds with tendon and/or bone exposure is challenging because of the insufficient blood supply to the wound bed. We describe our experience with 19 patients using a perifascial areolar tissue (PAT) graft with topical administration of basic fibroblast growth factor (bFGF) in the treatment of complex wounds with exposed tendons and/or bones in the extremities. Using a PAT graft is minimally invasive and technically easy, and the donor site is relatively preserved. However, PAT grafts for the treatment of a complex wound with large areas of exposed tendons and/or bones have sometimes failed to survive because of insufficient vascularization of the wound bed. Therefore, topical administration of bFGF, which promotes angiogenesis, was added to the graft. All grafts showed good graft survival and successfully covered the tendons and bones. Topical administration of bFGF accelerated vascularization in the PAT graft and facilitated wound healing by increasing the blood supply to the wound bed and achieved success with the PAT graft. In conclusion, using a PAT graft with topical administration of bFGF is a suitable option for the treatment of complex wounds with a large proportion of exposed tendons and/or bones. With minimal damage to the tissues near the wound, the PAT graft can be a useful option for limb salvage and could become a valuable tool for reconstructive surgeons.

Reconstruction for Skull Base Defect Using Fat-Containing Perifascial Areolar Tissue

Skull base reconstruction is a challenging task. The method depends on the anatomical complexity and size of the defect. We obtained tissue by harvesting fat-containing perifascial areolar tissue (PAT) for reconstruction of limited skull base defects and volume augmentation. We demonstrated the effective option for reconstruction of limited skull base defects and volume augmentation. From October 2013 to November 2015, 5 patients underwent operations using fat-containing PAT to fill the defect in skull base and/or perform volume replacement in the forehead. Perifascial areolar tissue with 5- to 10-mm fat thickness was harvested from the inguinal region. The fat-containing PAT was grafted to the defect contacting the vascularized wound bed. Patients were followed up in terms of their clinical symptoms and postoperative magnetic resonance imaging findings. Four patients were treated using fat-containing PAT after tumor resection. One patient was treated for a posttraumatic forehead depression deformity. The fat-containing PAT included 5- to 9-mm fat thickness in all cases. The mean size of grafted PAT was 65.6 cm (28-140 cm). The mean follow-up period was 18.6 months (12-31 months). There was no notable complication. There was no donor site morbidity. We can harvest PAT with fat easily and obtain the sufficient volume to treat the defect. It also could be used with other reconstructive method, such as a free flap or a regional flap to fill the left dead space. Therefore, fat-containing PAT could be additional options to reconstruction of skull base defect.