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BACKGROUND: Despite the central role of the platysma in face and neck rejuvenation, much confusion exists regarding its surgical anatomy. OBJECTIVES: This study was undertaken to clarify the regional anatomy of the platysma and its innervation pattern and to explain clinical phenomena, such as the origin of platysmal bands and their recurrence, and the etiology of lower lip dysfunction after neck lift procedures. METHODS: Fifty-five cadaver heads were studied (16 embalmed, 39 fresh, mean age 75 years). Following preliminary dissections and macro-sectioning, a series of standardized layered dissections were performed, complemented by histology and sheet plastination. RESULTS: In addition to its origin and insertion, the platysma is attached to the skin and deep fascia across its entire superficial and deep surfaces. This composite system explains the age-related formation of static platysmal bands, recurrent platysmal bands after complete platysma transection, and recurrent anterior neck laxity after no-release lifting. The facial part of the platysma is primarily innervated by the marginal mandibular branch of the facial nerve, whereas the submandibular platysma is innervated by the "first" cervical branches, which terminate at the mandibular origin of the depressor labii inferioris. This pattern has implications for postoperative dysfunction of the lower lip, including pseudoparalysis, and potential targeted surgical denervation. CONCLUSIONS: This anatomical study, comprised of layered dissections, large histology, and sheet plastination, fully describes the anatomy of the platysma including its bony, fascial, and dermal attachments, as well as its segmental innervation including its nerve danger zones. It provides a sound anatomical basis for the further development of surgical techniques to rejuvenate the neck with prevention of recurrent platysmal banding.

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BACKGROUND: The superior thyroid artery perforator flap has been presented previously in this Journal as a locoregional flap that provides an excellent tissue match with minimal donor morbidity for lateral face and temple defects. In the current study, the authors aimed to describe the microvascular anatomy of this flap. METHODS: The authors used in vivo computer tomographic angiography, cadaveric dissection, and ex vivo angiography in order to improve surgical safety and application of this technique. RESULTS: The authors provide a detailed map of the microvasculature that is critical to success in this technique, in addition to useful surface anatomical landmarks for ready application in the clinical scenario. Further, the authors discuss the anatomical basis of this flap with reference to the angiosome concept and the critical presence of true anastomoses. CONCLUSION: The superior thyroid artery perforator flap has been shown to be an excellent technique for reconstruction of lateral face and temporal soft tissue defects, providing a thin, pliable, hair-bearing tissue with minimal donor morbidity.

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UNLABELLED: The redundant tissues of the anterior neck are well suited as a donor site for fasciocutaneous flaps in head and neck reconstruction, with similar skin quality and numerous underlying perforators. However, historic cadaveric research has limited the use of this as a donor site for the design of long and/or large flaps for fear of vascular compromise. The authors undertook an anatomical study to identify the vascular basis for such flaps and have modified previous designs to offer the versatile and reliable superior thyroid artery perforator (STAP) flap. Forty-five consecutive computed tomographic angiograms of the neck were reviewed, assessing the vascular supply of the anterior skin of the neck. Based on these findings, eight consecutive patients underwent head and neck reconstruction using a flap based on the dominant perforator of the region. In all cases, a perforator larger than 0.5 mm was identified within a 2-cm radius of the midpoint of the sternocleidomastoid muscle at its anterior border. This perforator was seen to emerge through the investing layer of deep cervical fascia as a fasciocutaneous perforator and to perforate the platysma on its ipsilateral side of the neck, proximal to the midline. This was seen to be a superior thyroid artery perforator in 89 of 90 sides and an inferior thyroid artery perforator in one case. Eight consecutive patients underwent preoperative imaging and successful flap planning and execution based on this dominant perforator. The superior thyroid artery perforator (STAP) flap demonstrates reliable vascular anatomy and is well suited to reconstruction of a broad range of head and neck defects. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

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Although the lateral thigh flap has been well described as a fasciocutaneous flap based on one or more of the four perforators of the profunda femoris artery, the role for these individual perforators as perforator flaps has not been described. These profunda femoris artery perforators offer a particularly useful option in lower-limb reconstruction. In fact, a perforator flap based on the profunda femoris artery fourth perforator (PFA-P4) has not been described to our knowledge. We describe the utility of the PFA-P4 flap, offering modes of preoperative imaging and a role for its use in lower-limb reconstruction. Computed tomographic angiography (CTA) was able to identify the location and course of a PFA-P4, and Doppler ultrasound confirmed the CTA findings. A FA-P4 flap was designed and harvested, with direct closure of the donor site achieved. There were no operative complications. Perforator flaps based on the perforating branches of the profunda femoris artery have not been widely described, largely due to individual variability in perforator anatomy. With the advent of CTA for perforator mapping, the "freestyle" nature of such flaps is eliminated, and perforator flaps such as the PFA-P4 flap can be planned and harvested safely and confidently.

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Due to increasing clinical demand for adipose tissue, a suitable scaffold for engineering adipose tissue constructs is needed. In this study, we have developed a three-dimensional (3-D) culture system using bone marrow-derived mesenchymal stem cells (BM-MSC) and a Pluronic F-127 hydrogel scaffold as a step towards the in vitro tissue engineering of fat. BM-MSC were dispersed into a Pluronic F-127 hydrogel with or without type I collagen added. The adipogenic differentiation of the BM-MSC was assessed by cellular morphology and further confirmed by Oil Red O staining. The BM-MSC differentiated into adipocytes in Pluronic F-127 in the presence of adipogenic stimuli over a period of 2 weeks, with some differentiation present even in absence of such stimuli. The addition of type I collagen to the Pluronic F-127 caused the BM-MSC to aggregate into clumps, thereby generating an uneven adipogenic response, which was not desirable.

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