• Archives of Reconstructive Microsurgery
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• v.5 no.1
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• pp.24-34
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• 1996

There are many kinds of free flaps for management of extensive soft tissue defect of extremities in orthopaedic field. Free vascularized scapular flap is one of the most useful and relatively easy to application. This flap has been utilize clinically from early eighties by many microsurgical pioneers. Authors performed 102 cases of this flap from 1984 to 1995. We have to consider about the surgical anatomy of the flap, technique of the donor harvesting procedures, vascular varieties and anatomical abnormalities and success rate and the weak points of the procedure. This flap nourished by cutaneous branches from circumflex scapular vessels emerges from the lateral aspect of the subscapular artery 2.5-5cm from its lateral origin passing through the triangular space(bounded by subscapularis, teres minor, teres major, long head of triceps). The terminal cutaneous branch runs posteriorly around the lateral border of the scapular and divided into two major branches, those transeverse horizontally and obliquely to the fascial plane of overlying skin of the scapular body. We can utilize these arteries for scapular and parascapular flap. The vascular pedicle ranged from 5 to 10 cm long depends on the dissection, usually two venae comitantes accompanied circumflex scapular artery and its major branches. The diameter of the circumflex scapular artery is more than 1mm in adult, rare vascular variation. Surgical techniques : The scapular flap can be dissected conveniently with prone or lateral decubitus position, prone position is more easier in my experience. There are two kinds of surgical approaches, most of the surgeon prefer elevation of the flap from its outer border towards its base which known easier and quicker, but I prefer elevation of the flap from its outer border because of the lowering the possibilities of damage to vasculature in the flap itself which runs just underneath the subcutaneous tissue of the flap and provide more quicker elevation of the flap with blunt finger dissection after secure pedicle dissection and confirmed the course from the base of the pedicle. There are minimal donor site morbidity with direct skin closure if the flap size is not so larger than 10cm width. This flap has versatility in the design of the flap shape and size, if we need more longer and larger one, we can use parascapular flap or both. Even more, the flap can be used with latissimus dorsi musculocutaneous flap and serratus anterior flap which have common vascular pedicle from subscapular artery, some instance can combined with osteocutaneous flap if we include the lateral border of the scapular bone or parts of the ribs with serratus anterior. The most important shortcoming of the scapular free flap is non sensating, there are no reasonable sensory nerves to the flap to anastomose with recipient site nerve. Results : Among our 102 cases, overall success rate was 89%, most of the causes of the failure was recipient site vascular problems such as damaged recipient arterial conditions, and there were two cases of vascular anomalies in our series. Patients ages from 3 years old to 62 years old. Six cases of combined flap with latissimus dorsi, 4 cases of osteocutaneous flap for bone reconstruction, 62 parascapular flap was performed - we prefer parascapular flap to scapular. Statistical analysis of the size of the flap has less meaningful because of the flap has great versatility in size. In the length of the pedicle depends on the recipient site condition, we can adjust the pedicle length. The longest vascular pedicle was 14 cm in length from the axillary artery to the enter point cutaneous tissue. In conclusion, scapular free flap is one of the most useful modalities to manage the large intractable soft tissue defect. It has almost constant vascular pedicle with rare anatomical variation, easy to dissect great versatility in size and shape, low donor morbidity, thin and hairless skin.

• Smart Structures and Systems
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• v.20 no.3
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• pp.311-328
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• 2017

The characteristics of boundary layers have significant effects on the aerodynamic forces and vibration of the wind turbine blade. The incorporation of active trailing edge flaps (ATEF) into wind turbine blades has been proven as an effective control approach for alleviation of load and vibration. This paper is aimed at investigating the effects of external trailing edge flaps on the flow pattern and velocity distribution within a boundary layer of a NREL 5MW reference wind turbine, as well as designing a new type of velocity sensors for future validation measurements. An aeroelastic-aerodynamic simulation with FAST-AeroDyn code was conducted on the entire wind turbine structure and the modifications were made on turbine blade sections with ATEF. The results of aeroelastic-aerodynamic simulations were combined with the results of two-dimensional computational fluid dynamic simulations. From these, the velocity profile of the boundary layer as well as the thickness variation with time under the influence of a simplified load case was calculated for four different blade-flap combinations (without flap, with $-5^{\circ}$, $0^{\circ}$, and $+5^{\circ}$ flap). In conjunction with the computational modeling of the characteristics of boundary layers, a bio-inspired hair flow sensor was designed for sensing the boundary flow field surrounding the turbine blades, which ultimately aims to provide real time data to design the control scheme of the flap structure. The sensor element design and performance were analyzed using both theoretical model and finite element method. A prototype sensor element with desired bio-mimicry responses was fabricated and validated, which will be further refined for integration with the turbine blade structures.

• Maxillofacial Plastic and Reconstructive Surgery
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• v.29 no.6
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• pp.527-537
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• 2007

To evaluate criteria, indications, and prognosis of the various reconstructive methods on the patients with intraoral soft tissue defect who had been treated at Dept. of Oral and Maxillofacial Surgery, Pusan National University Hospital from 2003 to 2005, we have reviewed the clinical data of the patients and analysed. The results were as follows: 1. Tongue flaps have been mainly applied on anterior portion of palate and maxilla. The survival rate was high percent, but the cooperation of patient was inevitable for the success. 2. Palatal mucosa rotational flaps were available on relative large defect on palate, oroantral fistula site. The side effect was a scaring band from secondary healing on denuded donor palate site. Sometimes the band came to be a hinderance to swallowing, phonation. 3. Forearm free flap was a workhorse flap for everywhere in intraoral defects. We had used the flap on cheek, floor of mouth, tongue without any significant complications. But the application of the flap was required for long operation time, which was disadvantageous to the old, weak patients. 4. Cervical platysmal flap could be easily applicable for buccal cheek, floor of mouth after excision of the cancer lesion. The design of the flap could be made simultaneously on neck dissection, but the danger of cancer remnants on the flap always might be remained. 5. Buccal fat pad pedicled flap must have been a primary flap for repair of oroantral fistula especially on posterior maxilla. The flap survival will be expected if the considerations for above reconstructive methods on site, size, condition of defects primarily could be made.

• The Journal of the Korean dental association
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• v.50 no.8
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• pp.474-481
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• 2012

The periodontal flap surgery is the most widely utilized surgical procedure to reduce the pocket depth and to access the subgingival root surfaces for scaling and root planing. The diagnosis of the periodontal lesion and the objective of the surgery will dictate the type of flap procedure which will be utilized to obtain the best result. The incisions, type of flap and the selection of suturing design must be planned and executed to fit the problem. Periodontal flaps are designed to preserve gingival integrity and to gain access to root surfaces for residual calculus removal and to thoroughly remove granulation tissue so bone defects can be visualized and treated. Gentle and efficient procedures result in optimum healing and minimal postoperative pain. When flaps need to be repositioned apically or less often, coronally, then the flaps must sit passively at the appropriate level before suturing. To ensure this, buccal and lingual flaps need to be elevated beyond the mucogingival junction so the elasticity of the mucosa allows for flap mobility. Sometimes it may be necessary to extend the flap elevation apically with a split incision approach to minimize the effect of the less elastic periosteum. Vertical incisions can aid in flap positioning by allow ing the clinician to suture the flap at a different level to the adjacent untreated gingiva. In osseous periodontal surgery, flaps are apically positioned to minimize postoperative pocket depth. In regenerative periodontal surgery including implant surgery, soft tissue cove rage of bony defects, graft materials, membranes, and bio logic agents is important so sulcular incisions and light suturing techniques are crucial.

• Archives of Plastic Surgery
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• v.43 no.6
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• pp.529-535
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• 2016

Background The trapezius muscle flap is not usually the first reconstructive option for skin and soft tissue defects in the posterior neck and scalp due to surgeons' unfamiliarity with the surgical anatomy and developments in free tissue transfer techniques. The goals of this study were to describe the clinical use of trapezius flaps in posterior neck and scalp reconstruction, and to investigate the vascular anatomy of trapezius flaps in Asians in order to obtain information facilitating the safe design and elevation of flaps in which most of the muscle is preserved. Methods A retrospective chart review was performed of 10 patients who underwent trapezius muscle flap for posterior neck and scalp defects. We also performed an anatomical study of 16 flaps harvested from 8 preserved Asian adult cadavers and evaluated the main landmarks relevant for trapezius muscle flap. Results In the anatomical study, the mean vertical height from the inferior angle of the scapula to the point at which the superficial cervical artery penetrated the trapezius was $4.31{\pm}2.14cm$. The mean vertical height of the trapezius muscle flap pivot point was $9.53{\pm}2.08cm$ from the external occipital protuberance. Among the 10 flaps, partial necrosis on the overlaid skin graft occurred in 1 patient and postoperative seroma occurred in another patient. Conclusions Vascular variations in the trapezius muscle flap are uncommon in Asians, but when present, such variations appear to have little impact on harvesting the flap or on its circulation. The trapezius muscle flap is a viable alternative for posterior neck and scalp reconstruction.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.6
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• pp.464-470
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• 2018

In this paper, a practical method of estimating the flap hinge moments which change according to the aircraft flap operations was introduced. For the flap design, the hinge moment derived by structural load analysis and wind tunnel tests was able to be compared with the real flight hinge moment, and the static safety of the flap structure could be verified though this comparison. In order to perform the tests, two strain gauges were installed on the flap hinge and an onboard device for aircraft load monitoring was utilized. Through the ground test, the correlation between the strain and the moment of the flap hinge was calibrated with analytic and finite element analysis. During the flight test, strain signals together with the flap deflection angles and airspeed were recorded. Finally, the flight hinge moments could be predicted by the measured strain which was calibrated with the analytic and the finite element analysis.

• Archives of Plastic Surgery
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• v.40 no.6
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• pp.754-760
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• 2013

Background Classical flaps for perinasal defect reconstruction, such as forehead or nasolabial flaps, have some disadvantages involving limitations of the arc of rotation and two stages of surgery. However, a perforator-based flap is more versatile and allows freedom in flap design. We introduced our experience with reconstruction using a facial artery perforator-based propeller flap on the perinasal area. We describe the surgical differences between different defect subtypes. Methods Between December 2005 and August 2013, 10 patients underwent perinasal reconstruction in which a facial artery perforator-based flap was used. We divided the perinasal defects into types A and B, according to location. The operative results, including flap size, arc of rotation, complications, and characteristics of the perforator were evaluated by retrospective chart review and photographic evaluation. Results Eight patients were male and 2 patients were female. Their mean age was 61 years (range, 35-75 years). The size of the flap ranged from $1cm{\times}1.5cm$ to $3cm{\times}6cm$. Eight patients healed uneventfully, but 2 patients presented with mild flap congestion. However, these 2 patients healed by conservative management without any additional surgery. All of the flaps survived completely with aesthetically pleasing results. Conclusions The facial artery perforator-based flap allowed for versatile customized flaps, and the donor site scar was concealed using the natural nasolabial fold.

• Archives of Reconstructive Microsurgery
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• v.25 no.2
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• pp.25-28
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• 2016

Purpose: Reconstruction of small defects of the dorsal fingers and toes is a challenging task. Although adipofascial flap is widely used for these areas, additional refinements are warranted. In this paper, we define the appropriate defect size in the finger and toes that can be treated with the adipofascial flap, refine its surgical indications and present a few surgical tips. Materials and Methods: Twelve patients with dorsal defects of the fingers and toes were treated with a random-type adipofascial turn-over flap and skin graft. If the defect area exceeded the size that could be covered by a conventional design, the flap base was designed in oblique or curvilinear fashion to lengthen the flap. For accurate defect coverage, the width of the flap base was designed in an asymmetrical shape depending on the defect configuration, varying the width from 0.3 to 1.0 cm, as opposed to the standard 0.5 to 1.0 cm width. Moreover, the lateral limit of the flap was defined as the lateral axial line. The size of the defect ranged from $3.0{\times}1.7cm$ to $1.5{\times}1.3cm$. Results: All flaps survived completely. Gliding function of the hand was well preserved and there was no evidence of tendon adhesion. Conclusion: The small defect in the dorsal finger and toe can be defined as less than one phalanx-length, measuring about $3.0{\times}2.0cm$ in size. If the defect exceeds this dimension, it is recommended that a different option be considered. We believe the adipofascial flap is an excellent option for treating small defects.

• Smart Structures and Systems
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• v.17 no.5
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• pp.819-835
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• 2016

In this paper, the activities carried out within the EU funded Clean Sky Joint Technology Initiative (JTI GRA) Project and aimed at developing a morphing flap, are illustrated. The reference device is a regional aircraft single slotted flap, enhanced with deforming capabilities to obtain improved hyper-lift performance. The design started with the identification of the internal architecture, intended to allow camber variations. A concentrated-hinge architecture was selected, for its ability to fit different curvatures and for the possibility of easily realizing an "armadillo-like" configuration, then avoiding the use of a complicate deformable skin. The flap layout is made of segmented ribs, elastically hinged each other and span-wise connected by conventional spars. Relative rotations of the rib elements are forced by SMA structural actuators, i.e., cooperating in the external loads absorption. Super-elastic SMA are used to make up recovery elastic elements, necessary to regain the original shape after activation. These further elements in turn contribute to the overall flap rigidity. After assessing the hinge number and the size of the SMA active and passive elements, the advanced design phase was dealt with. It was aimed at solving manufacturing issues and producing the executive drawings. The realized demonstrator was finally tested in lab conditions to prove its functionality in terms of whether target shape actuation or attained shape preservation under loads. On the basis of the numerical results and the experimental outcomes, precious hints were obtained for further developments of the concept.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.35 no.7
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• pp.655-660
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• 2007

A canard-leading edge flap deflection scheduling laws have been established to enhance the maneuverability of the canard type fighter class aircraft. These scheduling laws are the relation of canard-leading edge flap deflections and flight conditions to maximize the lift-drag ratio. For these purposes, the corrected supersonic panel method has been used to predict the lift-drag characteristics due to canard-leading edge flap deflections. In addition, the high speed wind tunnel test has been conducted with 1/20 scale model to validate the predicted scheduling laws. Good agreements have been obtained compared with the results of high speed wind tunnel test. Based on the results obtained from the experimental and numerical studies, the corrected supersonic panel method has shown to be useful to establish the canard-leading edge flap deflection scheduling law for the aerodynamic design of canard type fighter class aircraft.