Free skin flap coverage of the upper extremity

Recent Advances in Upper Extremity Microsurgery: From Traditional to Perforator Flaps

The upper extremity has unique functional and aesthetic requirements. Reconstruction of upper extremity soft tissue defects should ideally provide coverage for vital structures, facilitate early mobilization, be thin and pliable to match its slim contour, and reestablish sensation. Perforator flaps can be raised on the superficial fascia, which creates a thin and pliable yet durable and supple flap option to match the contour and functional needs of the upper extremity. Comparisons to traditional reconstructive methods should be performed to assess whether these innovations in microsurgical reconstruction of upper extremity defects provide an improved functional and aesthetic benefit over traditional methods.

Thin and Thinned Anterolateral Thigh Flaps for Upper Extremity Reconstruction

Upper extremity reconstruction remains challenging due to the high functional and esthetic demands of this location. The anterolateral thigh (ALT) flap is a workhorse flap for microsurgical reconstruction of the upper extremity and can be elevated in various planes depending on desired thickness of the flap. Microsurgical reconstruction of the upper extremity often benefits from a thin flap that can resurface the extremity, which can provide improved functional and esthetic outcomes. This article reviews the anatomy, preoperative planning, and operative technique, as well as presents 4 cases to illustrate the outcomes and benefits of thin and thinned ALT flaps.

Advances in Soft Tissue Injuries Associated with Open Fractures

Management of soft tissue injury is a key component in the overall treatment of upper extremity fractures. Hand surgeons must rely on their armamentarium for treating soft tissue deficits for functional outcomes. Understanding the role of fracture fixation and wound adjuncts, including negative pressure wound therapy and dermal regenerative templates, is the keys to success. In addition, detailed knowledge of local and free tissue options is essential for hand reconstruction.

On-skin biosensors for noninvasive monitoring of postoperative free flaps and replanted digits

Severe soft tissue defects and amputated digits are clinically common injuries. Primary treatments include surgical free flap transfer and digit replantation, but these can fail because of vascular compromise. Postoperative monitoring is therefore crucial for timely detection of vessel obstruction and survival of replanted digits and free flaps. However, current postoperative clinical monitoring methods are labor intensive and highly dependent on the experience of nurses and surgeons. Here, we developed on-skin biosensors for noninvasive and wireless postoperative monitoring based on pulse oximetry. The on-skin biosensor was made of polydimethylsiloxane with gradient cross-linking to create a self-adhesive and mechanically robust substrate that interfaces with skin. The substrate was shown to exhibit appropriate adhesion on one side for both high-fidelity measurements of the sensor and low risk of peeling injury to delicate tissues. The other side demonstrated mechanical integrity to facilitate flexible hybrid integration of the sensor. Validation studies using a model of vascular obstruction in rats demonstrated the effectiveness of the sensor in vivo. Clinical studies indicated that the on-skin biosensor was accurate and more responsive than current clinical monitoring methods in identifying microvascular conditions. Comparisons with existing monitoring techniques, including laser Doppler flowmetry and micro-lightguide spectrophotometry, further verified the sensor's accuracy and ability to identify both arterial and venous insufficiency. These findings suggest that this on-skin biosensor may improve postoperative outcomes in free flap and replanted digit surgeries by providing sensitive and unbiased data directly from the surgical site that can be remotely monitored.

Temporoparietal Fascial Free Flap: A Systematic Review

ABSTRACT

The temporoparietal fascial flap (TPFF) is a versatile tool used in head and neck reconstructive surgeries as well as distal upper and lower extremity reconstructions. Depending on the anatomical location and characteristics of the recipient site soft tissue defects, harvesting techniques for TPFF retrieval may include elevation as a pedicle or a free flap, inclusion of the temporalis muscle and/or adjacent calvarial bone as a composite flap. The TPFF as a free flap is not only used for soft tissue coverage of various defects, and it can be used as a joint gliding surface with coverage of nerve and tendons after repair or trauma. This article includes a systematic search of the medical literature for indications, historical background, techniques, current perspective, and complications along with the pros and cons of the free TPFF compared with other potential reconstructive options.

RECONSTRUCTION OF UPPER LIMB SOFT TISSUE INJURIES, EXCEPT FOR FINGERTIPS LESIONS

Objective:

The main purpose of this work was to evaluate the advantages and disadvantages of reconstructive procedures applied in upper limb soft tissue injuries according to their location.

Methods:

The study involved 94 male and 22 female patients (116 total) operated between April 2001 and November 2017 due to traumatic injuries in a upper limb. Individuals were evaluated considering their age, sex, etiology, reconstruction area , applied methodology and complications. The finger injuries were excluded.

Results:

The performed reconstruction procedures include 29 skin grafts; six advancement flaps; seven rotation flaps; 33 pedicled fasciocutaneous flaps, 9 free fasciocutaneous flaps; 5 pedicled muscle flaps; 12 free muscle flaps, three pedicled musculocutaneous flaps; one free musculocutaneous flap; 11 neurovascular free flaps.

Conclusion:

Reconstructive procedures in the upper limbs are diverse, varying from skin grafting to free flaps. The indication of the best option depends on the type of injurie and the surgeon. The final goal is to reach the best functional result combined with the lowest possible morbidity. Level of Evidence IV, Case series.

Preclinical efficacy of stem cell therapy for skin flap: a systematic review and meta-analysis

Background

A skin flap is one of the most critical surgical techniques for the restoration of cutaneous defects. However, the distal necrosis of the skin flap severely restricts the clinical application of flap surgery. As there is no consensus on the treatment methods to prevent distal necrosis of skin flaps, more effective and feasible interventions to prevent skin flaps from necrosis are urgently needed. Stem therapy as a potential method to improve the survival rate of skin flaps is receiving increasing attention.

Methods

This review followed the recommendations from the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statements. Twenty studies with 500 animals were included by searching Web of Science, EMBASE, PubMed, and Cochrane Library databases, up until October 8, 2020. Moreover, the references of the included articles were searched manually to obtain other studies. All analyses were conducted using Review Manager V.5.3 software.

Results

Meta-analysis of all 20 studies demonstrated stem cell treatment has significant effects on reducing necrosis of skin flap compared with the control group (SMD: 3.20, 95% CI 2.47 to 3.93). Besides, subgroup analysis showed differences in the efficacy of stem cells in improving the survival rate of skin flaps in areas of skin flap, cell type, transplant types, and method of administration of stem cells. The meta-analysis also showed that stem cell treatment had a significant effect on increasing blood vessel density (SMD: 2.96, 95% CI 2.21 to 3.72) and increasing the expression of vascular endothelial growth factor (VEGF, SMD: 4.34, 95% CI 2.48 to 6.1).

Conclusions

The preclinical evidence of our systematic review indicate that stem cell-based therapy is effective for promoting early angiogenesis by up regulating VEGF and ultimately improving the survival rate of skin flap. In summary, small area skin flap, the administration method of intra-arterial injection, ASCs and MSCs, and xenogenic stem cells from humans showed more effective for the survival of animal skin flaps. In general, stem cell-based therapy may be a promising method to prevent skin flap necrosis.

Soft tissue coverage of the upper limb: A flap reconstruction overview

Different opinions about the reconstructive choice for upper limb are described in literature: advancement or rotation flaps, regional flaps and free flaps are the most common reconstructive options. Local and regional flaps can be used to cover small defects while large wounds require the use of free flaps or distant pedicled flaps. The coverage of large wounds opens a discussion about when to use free flaps and when distant pedicled flaps. This review will describe the different methods used for the coverage of soft tissues injuries affecting hand and/or forearm (excluding fingers). The aim is to show all flap reconstructive options in order to support the inexperienced surgeon during the management of traumatic injuries of the upper limb.

Thirty-Day Outcomes following Upper Extremity Flap Reconstruction

Introduction  Flap reconstructions of upper extremity defects are challenging procedures. It is important to understand the surgical outcomes of upper extremity flap reconstruction, as well as associations between preoperative/perioperative variables and complications.

Materials and Methods  The National Surgical Quality Improvement Program (NSQIP) database was queried for patients from 2005 to 2016 who underwent flap reconstruction of an upper extremity defect. Patient and perioperative variables were collected for identified patients and assessed for associations with rates of any complication and major complications.

Results  On multivariate analysis, American Society of Anesthesiologists (ASA) classification >2, bleeding disorder, preoperative steroid use, free flap reconstruction, wound classification other than clean, and nonplastic surgeon specialty were independently associated with any complications. Bleeding disorder, ASA classification >2, male gender, wound classification other than clean, and preoperative anemia were independently associated with major complications. Free flap reconstruction was associated with increased length of stay, operative time, any complications, transfusions, and unplanned reoperations.

Conclusion  There is an association between complications in patients undergoing upper extremity free flap reconstruction and ASA classification >2, preoperative anemia, preoperative steroid use, bleeding disorders, and contaminated wounds. Male patients may require more thorough counseling in activity restriction following reconstruction. Free flaps for upper extremity reconstruction will require increased planning to reduce the chance of complications.

Arm reconstruction

The arm is less often concerned by reconstructive surgeries than more distal parts of the upper extremity. However, when affected, the arm is frequently part of complex mutilating injuries involving composite defects. For a given traumatic or oncologic defect, there are several reconstructive options and choosing the right sequence may pose a challenge even to the most experienced surgeon. The latter must integrate not only functional and esthetic requirements, but also the surgeon's habits, especially in situations of emergency. Once life-threatening conditions are averted, wound debridement, bony stabilization, neurovascular, and cutaneous reconstruction tailored to the defects should be performed in a single-stage procedure. Functionally, prompt bony stabilization is necessary to allow early mobilization. Diaphyseal shortening of the humerus can be a salvage procedure to avoid nerve and vascular grafting, with good biomechanical tolerance up to 5cm. Restoration of adequate elbow motion sometimes requires muscle transfer and should be a main concern, as proper positioning of the hand during daily activities demands a functional elbow joint. Esthetically, the surgeon must choose the most cosmetic skin coverage option whilst limiting morbidity of the donor site area. The flaps vascularized by the sub- scapular or thoraco-dorsal vessels are the most useful flaps for arm reconstruction. This paper discusses the reconstructive sequence of complex defects of the arm and provides a review of commonly used reconstructive techniques supported with illustrative cases.

Free Tissue Transfer for Upper Extremity Reconstruction

With the advent of the Industrial Revolution, traumatic injuries of the upper extremity increased exponentially. As a result, surgeons began to reevaluate amputation as the standard of care. Following the Second World War, local and regional pedicled flaps became common forms of traumatic upper extremity reconstruction. Today, microsurgery offers an alternative when options lower on the reconstructive ladder have been exhausted or will not produce a desirable result. In this article, the authors review the use of free tissue transfer for upper extremity reconstruction. Flaps are categorized as fasciocutaneous, muscle, and functional tissue transfers. The thin pliable nature of fasciocutaneous flaps makes them ideal for aesthetically sensitive areas, such as the hand. The radial forearm, lateral arm, scapula, parascapular, anterolateral thigh, and temporoparietal fascia flaps are highlighted in this article. Muscle flaps are utilized for their bulk and size; the latissimus dorsi flap serves as a "workhorse" free muscle flap for upper extremity reconstruction. Other muscle flaps include the rectus abdominis and serratus anterior. Lastly, functional tissue transfers are used to restore active range of motion or bony integrity to the upper extremity. The innervated gracilis can be utilized in the forearm to restore finger flexion or extension. Transfer of vascularized bone such as the fibula may be used to correct large defects of the radius or ulna. Finally, replacement of "like with like" is embodied in toe-to-thumb transfers for reconstruction of digital amputations.

Reconstruction of post-traumatic upper extremity soft tissue defects with pedicled flaps: An algorithmic approach to clinical decision making

PURPOSE

Pedicled flaps are still the workhorse flaps for reconstruction of upper limb soft tissue defects in many centers across the world. They are lifeboat options for coverage in vessel deplete wounds. In spite of their popularity existing algorithms are limited to a particular region of upper limb; a general algorithm involving entire upper limb which helps in clinical decision making is lacking. We attempt to propose one for the day to day clinical practice.

METHODS

A retrospective analysis of patients who underwent pedicled flaps for coverage of post-traumatic upper extremity (arm, elbow, forearm, wrist & hand) soft tissue defects within the period of January 2016 to October 2017 was performed. Patients were divided into groups according to the anatomical location of the defects. The flaps performed for different anatomical regions were enlisted. Demographic data and complications were recorded. An algorithm was proposed based on our experience, with a particular emphasis made to approach to clinical decision making.

RESULTS

Two hundred and twelve patients were included in the study. Mean age was 27.3 years (range: 1-80 years), 180 were male, and 32 were female. Overall flap success rate was 98%, the following complications were noted marginal flap necrosis requiring no additional procedure other than local wound care in 32 patients (15%), partial flap necrosis requiring flap advancement or extra flap in 15 patients (7%), surgical site infection in 11 patients (5%), flap dehiscence requiring re-suturing in 5 patients (2.4%), total flap necrosis 4 patients (2%).

CONCLUSION

The proposed algorithm allows a reliable and consistent method for addressing diverse soft tissue defects in the upper limb with high success rate.

Comparison of perioperative complications of pedicled island flap in reconstruction of extremities

PURPOSE

The aim of this study was to analyze the differences in perioperative complications for pedicled island flaps in the reconstruction of extremities and to identify the factors contributing to pedicled island flap necrosis. Furthermore, the flap indications based on these outcomes are summarized.

METHODS

Based on the inclusion criteria, 228 skin flaps were included in this study. Univariate and multivariate analyses were used to identify the risk factors for pedicled island flap necrosis. Differences in perioperative complications between upper and lower extremities were analyzed using the chi-square test or Fisher's exact test.

RESULTS

The average age of the patients was 38 years. The overall complication rate was 21.93%, including partial flap necrosis (10.09%) and total flap necrosis (5.70%). The overall complication rate and flap necrosis rate in upper extremity reconstruction were significantly lower than the rates in lower extremity reconstruction. Flap area and postoperative wound infection were statistically significant risk factors for pedicled island flap necrosis in extremity reconstruction. Preoperative contamination of the wound bed was a statistically significant risk factor for postoperative wound infection.

CONCLUSIONS

The flap area and postoperative wound infection were both independent risk factors for pedicled island flap necrosis in extremity reconstruction. The causes contributing to the differences in perioperative complications between upper and lower extremities reconstruction included preoperative contamination of the wound bed, postoperative wound infection, and the flap area but were also related to anatomical factors of the skin flap. Pedicled island flaps are more suitable for small- and medium-sized soft tissue defects.

Versatility of Free Cutaneous Flaps for Upper Extremity Soft Tissue Reconstruction

The goals of upper extremity soft tissue reconstruction should go well beyond providing coverage and restoring function. As the field of reconstructive microsurgery has evolved, free cutaneous flaps (FCFs) are gaining wider application. The advantages of FCF include minimizing donor-site morbidity by preserving the muscle and fascia, improving versatility of flap design, and superior aesthetic results. This review highlights the application of anterolateral thigh, superficial circumflex iliac artery, deep inferior epigastric perforator, superficial inferior epigastric artery, and flow-through flaps for reconstruction of upper extremity defects. These flaps share several qualities in common: well-concealed donor sites, preservation of major arteries responsible of providing inflow to distal extremity, and potential for a two-team approach (donor and recipient sites). While the choice of flaps should be decided based on individual patient and defect characteristics, FCF should be considered as excellent options to achieve the goals of upper extremity reconstruction.

Free lateral tarsal artery perforator flap with functioning extensor digitorum brevis muscle for thenar reconstruction: a case report

In this case report, we describe reconstructive surgery in one patient using a free lateral tarsal artery perforator flap with a functioning extensor digitorum brevis muscle. A 47-year-old woman sustained a crush-avulsion injury to her dominant right hand while working in a factory. A large thenar skin and muscle defect (5.5 cm × 4.0 cm) occurred as a consequence of surgical debridement. The skin and muscle defect was repaired using a free lateral tarsal artery perforator flap with a functioning extensor digitorum brevis muscle in a single operation. The donor site defect was repaired using a full-thickness skin graft. The patient recovered without postoperative complications. The patient showed satisfactory functional gain without significant donor site morbidity at the 4-year follow-up visit. Thus, we have demonstrated that a functional reconstruction of a thenar skin defect complicated by muscle loss is possible by transferring a free lateral tarsal artery perforator flap with the underlying extensor digitorum brevis muscle.