Osteocutaneous Free Flap Research Articles

Comparison of Radial Forearm With Fibula and Scapula Osteocutaneous Free Flaps for Oromandibular Reconstruction

To compare our experience with the osteocutaneous radial forearm free flap (group 1) (n = 108) with other commonly used osteocutaneous free flaps (group 2) (n = 56) such as the fibula and scapula in single-stage oromandibular reconstruction. Retrospective case review. Tertiary-care academic medical center. One hundred sixty-three consecutive patients who underwent 164 mandibular reconstructions with osteocutaneous free flaps. Assessment of preoperative and intraoperative variables for both groups. We compared recipient-site complication rate, intensive care unit stay, total hospital stay, and postoperative function. The most common donor site used was the radius (n = 108 [66%]), followed by the fibula (n = 36 [22%]) and scapula (n = 20 [12%]). Mean follow-up was 29 months (range, 1-116 months). Group 2 patients had larger soft tissue and/or bony defects. Surgical and medical complication rates and major donor site morbidity in group 1 were similar or better when compared with those in group 2. The lengths of the intensive care unit (4 vs 7 days; P = .009) and hospital stays (13 vs 15 days; P = .06) were shorter in group 1. Although the microvascular success rate was similar in both groups, the local wound complication rate was significantly better for group 1. The difference for the length of intensive care unit stay was statistically significant and potentially amounts to more than 6000 dollars of savings. Functional outcomes, including the ability to tolerate oral diet, tracheostomy presence, and dental rehabilitation, were similar between the groups. The primary site long-term morbidity, donor site morbidity, and postoperative function of osteocutaneous radial forearm free flaps are comparable to those of other commonly used osteocutaneous free flaps such as the fibula and scapula when used in single-stage oromandibular reconstruction.

La revascularisation digitale ectopique temporaire

We present two clinical cases with complete amputation of multiple digits that were salvaged after having been successfully implanted on ectopic sites. The first case concerns a 73-year-old patient, who suffered a severe crush injury of his right hand that resulted in amputation of all four long fingers and an extensive tissue loss of the palm and the dorsum of the hand. Two of the amputated digits, that were considered to be replantable, were implanted on the dorsum of the left foot. The hand defect was covered with a pedicle groin flap. After six weeks, the two ectopically implanted fingers were transferred to their proper anatomical site. Several reconstructive procedures were performed later, in order to lengthen the first ray of the injured hand, and to deepen the first web space. Satisfactory functional results were recorded after eighteen months of follow-up. The second patient concerns a 45-year-old male patient, who had a gun shot accident of his right hand. The injury resulted in a composite tissue loss of the hand with complete amputation of his four long fingers. All fingers were implanted on the left forearm, while the hand defect was reconstructed using an osteocutaneous free flap of the iliac crest. Six weeks after the initial procedure, the ectopically implanted digits were transferred — as a single free flap — to the hand. We described with details the local conditions of the injured hands in both cases, and discuss the reasons we decided to perform this sophisticated method in order to preserve the viability and function of those totally amputated fingers. The recipient sites were selected in a distance from the injured area, always considering the availability and size of appropriate recipient vessels, and the safety of the surgical procedure. We agree that the whole concept of this procedure is very demanding, and requires several microsurgical operations with high risk of complications. However, it does deserve special consideration in reconstructive microsurgery, since it offers the possibility to salvage multiple amputated digits, by preserving the anatomy and restoring the function of severely injured hands.

PD.165 Establishing a role for the double-paddle osteocutaneous radial forearm free flap in composite oromandibular defects

PD.165 Establishing a role for the double-paddle osteocutaneous radial forearm free flap in composite oromandibular defects

P.161 Reconstruction of the total lower lip, chin and mandible with the composite radial forearm-palmaris longus and fibular osteocutaneous free flaps

P.161 Reconstruction of the total lower lip, chin and mandible with the composite radial forearm-palmaris longus and fibular osteocutaneous free flaps

Fibular osteocutaneous free flap application on a recurred mandibular carcinoma with osteoradionecrosis

Fibular osteocutaneous free flap application on a recurred mandibular carcinoma with osteoradionecrosis

Use of the 2.0-mm locking reconstruction plate in primary oromandibular reconstruction after composite resection

To review our experience with 2.0-mm locking reconstruction plate (LRP) system for patients requiring oromandibular reconstruction. Retrospective case review of 43 consecutive patients who underwent mandibular composite resection with immediate reconstruction. Tertiary care center. Forty-three patients underwent oromandibular reconstruction with the 2.0-mm mandibular LRP system and free flaps containing vascularized bone. Mean follow-up was 11 months. There were no intraoperative difficulties utilizing this system. Two (5%) patients had partial fasciocutaneous flap loss resulting in plate exposure. There were no instances of plate fracture or complications requiring plate removal to date. 2.0-mm LRP mandibular system is reliable even in the setting of previous or adjuvant radiation therapy. Its technical ease of application, contouring malleability, and very low profile have proven to be advantageous in oromandibular reconstruction. No previous descriptions of use of the 2.0-mm LRP in combination with osteocutaneous free flaps for mandibular reconstruction are found in the literature. C.

Utility of bone scanning in the postoperative assessment of fibula-free tissue transfers

Objectives: The fibula osteocutaneous free flap has proven one of the most versatile and reliable flaps available for reconstruction of mandibular defects. Survival rates are exceedingly good with most centers reporting survival in >95% of cases. Viability of the bone is indirectly inferred by examination and visibility of the skin paddle. Occasionally, the skin paddle dies and the status of the bone is unknown. In these instances, one must ascertain the status of the bone in order to plan appropriately. We report on our experience with bone scanning in differentiating bone survival from bone death when the skin paddle has necrosed. Setting: Tertiary referral academic center Oregon Health & Science University. Methods: From 1998 to 2004, 130 fibula osteocutaneous free tissue transfers were undertaken. Results: In 7 of these, viability of the bone was questioned (5 skin paddle necrosis, 2 buried flap with no external monitor and a severe neck infection. Bone scanning was undertaken to help in operative planning. In 4 flaps, the bone paddle was felt to be alive on scan and confirmed intraoperatively. The skin paddle was debrided and replaced with a radial forearm free flap. Bone viability was confirmed at most recent follow-up. In 3 cases, the bone was confirmed to be nonviable by bone scan and confirmed by inspection intraoperatively. These cases were repaired with a second fibula free flap. Conclusion: Bone scanning is a useful investigation in cases where viability of the bone is in question. In flaps where the bone is buried or those in which the skin paddle has died, a positive bone scan will allow for planning of only soft tissue coverage, whereas a negative bone scan will imply a second bone flap.

Should the donor radius be plated prophylactically after harvest of a radial osteocutaneous flap? A cost-effectiveness analysis.

The objective of this study was to assess the cost-effectiveness of prophylactic plating of the donor radius after harvest of a radial osteocutaneous flap. Costs were measured from a Ministry of Health perspective, and effectiveness in terms of quality adjusted life years (QALYs.) A literature search identified 22 studies reporting complications of radial osteocutaneous free flaps, and nine studies reporting complications of radius plating. The rates of the various complications were pooled to provide the probability of each clinically important complication. A decision analytic model was used to determine the total costs, and QALYs for each of the treatment options. The expected direct costs for prophylactic plating and treatment after fracture were $2071 and $140, respectively. The expected QALYs for prophylactic plating and treatment after fracture were 8.55 and 9.92, respectively. It was concluded that prophylactic plating of the donor radius is not a cost-effective approach when compared to the treatment of donor radius fractures after they occur.

Management of oromandibular cancers.

To emphasize the role and importance of multidisciplinary approach in the management of oral cavity cancers involving the mandible. Descriptive study. The Departments of Plastic and Reconstructive Surgery, ENT / Head and Neck Surgery and Radiation Oncology, Combined Military Hospital, Rawalpindi. Duration spans over a period of six years. A total of 63 patients who had biopsy-proven oromandibular tumors, after thorough assessment / staging in Joint Head and Neck Oncology Clinic, underwent resection and reconstruction for malignant oral cavity tumors involving the mandible were included in the study. All the resected tumor specimen were sent for histopathology. All the post-resection defects were properly classified and reconstructed by the plastic surgery team. Postoperatively, all the patients underwent adjuvant full dose radiotherapy at the Department of Radiation Oncology. Complications were recorded and managed accordingly. At one year follow-up all the available patients were assessed for functional and aesthetic restoration and recurrences. Out of 63 patients there were 40 males and 23 females (ratio 1.7 : 1) with an average age of 50 years. Tumor-free resection margins could be achieved in 56 patients. In 88% cases tumor was a Squamous cell carcinoma. Radical neck dissections were carried on in 27 patients. Radial forearm free flap was used in 27 patients, pectoralis major myocutaneous flap in 19, free fibula osteocutaneous flap in 10, rectus-abdominis myocutaneous free flap with Implant was used in 3 patients to reconstruct the post-resection defects. There was only one total flap loss and 3 partial flap losses. Implant exposure was encountered in 4 instances with 3 major and 5 minor fistulae. At one year follow-up, 56 patients were available. Thirty-seven patients had intelligible speech, 15 patients were taking normal diet and in 33 patients there was a satisfactory mandibular contour restoration. Seven patients had recurrences, 2 were not traceable and 5 patients had died by that time. A multidisciplinary collaboration is the key to effectively manage this group of extremely debilitating malignancies.

Renewed popularity of scapular osteocutaneous free flaps for complex head and neck reconstruction

Renewed popularity of scapular osteocutaneous free flaps for complex head and neck reconstruction

Osteoradionecrosis of the Mandible after Oromandibular Cancer Surgery

Although postoperative radiotherapy has proved effective in improving local control and survival in patients with head and neck cancers, its complications, especially mandibular osteoradionecrosis, reduce the quality of life. Mandibular surgery before the radiotherapy adds an additional risk factor for osteoradionecrosis. This study reviews patients in Chang Gung Memorial Hospital, Taipei, Taiwan, over a 10-year period, who underwent intraoral cancer resection followed by postoperative radiotherapy and thereafter developed osteoradionecrosis of the mandible. A total of 24 men and three women with a mean age of 49.9 years were identified and included in the study. In 10 cases, tumor resection was performed with a marginal mandibulectomy; in eight cases, tumor resection was performed after mandibular osteotomy; and in three cases, a segmental mandibulectomy was performed, and the defect was reconstructed with a fibula osteoseptocutaneous flap. In six cases, tumor excisions were performed without interfering with the mandibular continuity. Patients received postoperative external beam radiotherapy into the primary site and the neck, with a mean dose (+/-SD) of 5900 +/- 1300 cGy in an average of 35 fractions during an average of 6.5 weeks. The average elapsed time between the end of radiation therapy and clinical diagnosis of osteoradionecrosis of the mandible was 11.2 months (range, 2 to 36 months). The time elapse between the end of the radiation therapy and the diagnosis of osteoradionecrosis was influenced by initial treatment (Kruskal-Wallis test: n = 27, chi-square = 12.884, p < 0.005), and this period was shorter if the mandibular osteotomy or marginal mandibulectomy was performed (the two lowest mean ranks in the test). However, if the initial surgery resulted in a segmental mandibulectomy reconstructed with a fibula osteoseptocutaneous flap, onset of the osteoradionecrosis was relatively late (Kruskal-Wallis test: n = 21, chi-square = 7.731, p = 0.052). After resection of osteoradionecrotic bone and surrounding soft tissue, 22 patients underwent reconstructive procedures with a fibula osteoseptocutaneous flap, and five patients underwent reconstructive procedures with an inferior genicular artery osteoperiosteal cutaneous flap. One fibula osteoseptocutaneous flap showed total failure and another showed a 25 percent skin loss; both were revised with pedicled flaps. The skin paddle of an inferior genicular artery flap was replaced with an anterolateral thigh flap because of anatomic variation of the skin vessel. Once the diagnosis of osteoradionecrosis is established, replacement of the dead bone and surrounding tissue with a vascularized free bone flap is inevitable, and a composite osteocutaneous free flap is a good option.

Midface reconstruction with the fibula free flap.

To evaluate the use, indications, and outcomes of the fibula osteocutaneous free flap when reconstructing the midface. Retrospective review of a case series. Tertiary referral center. We evaluated all patients requiring midface reconstruction after tumor resection between January 1, 1994, and January 1, 2000. Twenty-seven individuals who lacked sufficient retentive surfaces and/or teeth to support a conventional prosthesis were offered vascularized bony reconstruction. All patients underwent fibular osteocutaneous free flap reconstruction of the midface: 16 primarily, 11 secondarily. Success of free tissue transfer, perioperative complications, oral diet, speech, type of dental reconstruction, and cosmesis. Twenty-six of 27 flaps survived. Four patients had wound complications managed successfully with local wound care. Fourteen patients achieved a regular diet and 13 patients maintain a soft diet. Eighteen patients had osseointegrated implants placed, and 14 patients used an implant-borne prosthesis. Cosmetic results were judged to be excellent in 14 patients; good in 8; fair in 4; and poor in 1. Use of the fibula osteocutaneous free flap to reconstruct the midface is highly reliable and our flap of choice for lower maxillary defects requiring bony reconstruction. However, when orbitozygomatic support is the primary objective, the utility of this flap is limited. Because of the complexity of this procedure, the choice of midface reconstruction technique should be individualized for each patient.

Malignant ameloblastoma: Classification, diagnostic, and therapeutic challenges

Ameloblastoma is a benign odontogenic neoplasm of the mandible and maxilla that rarely exhibits malignant behavior. We report the case of an aggressive malignant ameloblastoma of the mandible that presented with an unusual multiphasic, histologic pattern. Initial fine needle aspiration and radiographic findings showed features consistent with a benign, fibro-osseous lesion. However, aggressive growth and the association of enlarged submandibular lymph nodes suggested a more malignant potential. Treatment consisted of an angle-to-angle composite mandibular resection, right modified neck dissection, left functional supraomohyoid neck dissection, and anterior chin skin resection with iliac crest osteocutaneous free flap reconstruction. Microscopic evaluation showed primarily malignant ameloblastoma without cellular atypia and extensive fields of fibro-osseous tissue with smaller fields of clear cell odontogenic tumor. This multiphasic, histologic arrangement may explain the perplexing preoperative microscopic diagnosis, suggesting a benign fibro-osseous lesion. Of the lymph nodes analyzed, one from the right submandibular triangle exhibited metastatic, benign-appearing ameloblastoma without fibro-osseous or clear cell features. The absence of cellular features of malignancy in the tumor mass and lymph node metastasis suggest that the lesion should be classified as malignant ameloblastoma rather than ameloblastic carcinoma or odontogenic carcinoma. A malignant ameloblastoma with all 3 of the aforementioned microscopic features has not been previously reported. We review the classification of epithelial odontogenic malignancies. Lesions showing multiphasic patterns can create diagnostic dilemmas and may require extensive surgical sampling and/or removal to establish an accurate diagnosis. (Am J Otolaryngol 2002;23:44-48. Copyright © 2002 by W.B. Saunders Company)

Donor-Site Complications in Vascularized Bone Flap Surgery

Microvascular osteocutaneous free flaps have given reconstructive surgeons a powerful tool in the reconstruction of composite defects in head and neck surgery. Radial forearm, scapula, iliac crest, and fibula flaps have been used extensively in mandibular reconstruction. The inevitable donor-site morbidity of these osteocutaneous flaps has received less attention than the reconstructive advantages. We have reviewed the literature for each type of flap to determine the kind, incidence, and consequences of flap associated morbidity. In the future, tissue-engineered prefabricated free flaps might play an important role.

Modeling a fibula transplant in mandibular reconstructions: evaluation of the effects of a minimal number of osteotomies on the contour of the jaw.

The fibula osteocutaneous free flap has become the preferred method for most cases of mandibular reconstruction after oncologic surgical ablation. To recreate the parabolic form of the mandible, the fibula has to be divided up into segments using a closed wedge osteotomy technique. The number of osteotomies is preferably kept to a minimum so that segmental periosteal circulation is not compromised and also to keep operating time to a minimum. The limited number of osteotomies creates an angular contour. The aim of this study was to establish the degree to which overcorrection or undercorrection would occur when a subtotal reconstruction from ramus to ramus was simulated using five bony segments and four osteotomies. The study was carried out using 30 preserved jaws; the contour lines of the jaws were transferred onto tracing paper using a cardboard template. The contour of the mandible was divided into five sections (ramus, body, symphysis, body, and ramus). Because of the cutting off of the curvature in the original jaw outline, the lateral side of the body will become narrower and the chin broader. This also results in an underprojection (displacement) of the chin. To follow the original contour of the jaw as accurately as possible, all these anomalies must be minimized. The amount of under- and overprojection is calculated for a displacement of 1.0, 1.5, 2.5, 5.0, 7.5, and 10 mm of the chin. The most accurate reconstruction of the mandibular contour is achieved with a displacement of 1.5 or 2.5 mm. To preserve sufficient periosteal circulation, the minimum width of bone segments must be 15 mm or more. This concerns especially the symphysis section. On the basis of a fibula thickness of 14 mm, the internal bone width of the symphysis section is calculated. With a displacement of 1.5 mm, the average internal width of the bone segment is 14.8 mm, with a range of 9.9 to 23.0 mm (95 percent confidence interval, 12.8 to 16.7 mm). Therefore, a displacement of 2.5 mm with an internal bone width of 16.4 mm is preferred (range, 11.9 to 24.8 mm; 95 percent confidence interval, 15.5 to 18.2 mm). The loss of lateral projection is minimal (5.8 mm) and the resulting chin width is acceptable (average, 35.0 mm). In conclusion, we propose that in a subtotal procedure, an acceptable jaw reconstruction can be achieved with a limited number of osteotomies. The bone length of the symphysis section remains within safe limits. If the defect is of limited dimensions, then the resulting jaw contour is even more accurate.

Retrospective case series of primary and secondary microvascular free tissue transfer reconstruction of midfacial defects

Statement of Problem. Midfacial defects arising from tumor extirpation or trauma may involve any portion of the central area of the face, including the palate, maxilla, orbit, lip, and/or nose. Speech, mastication, swallowing, and cosmesis are significantly impaired and present a unique challenge to the reconstructive surgeon. Purpose. This study evaluated the functional and cosmetic success of both soft tissue and osteocutaneous free flap reconstruction of the midface. Material and Methods. A retrospective chart review of 34 patients who underwent primary and secondary free flap reconstruction of the midface was conducted. The main outcome measures were perioperative complications, diet, speech intelligibility, type of dental restoration, and cosmetic result. Results. Fifteen patients underwent soft tissue free flap reconstruction of the midface. Six of these patients also had additional nonvascularized free cranial bone grafts to improve restoration of the orbitozygomatic region. Nineteen patients who might have required osseointegrated implants to anchor a dental prosthesis underwent osteocutaneous free flap reconstruction. Thirty-three of 34 free flaps survived, and wound complications were minimal. After surgery, 20 patients were able to eat a regular diet and 14 a soft diet. All patients had intelligible speech over the telephone. Ten patients used a dental prosthesis (5 conventional and 5 implant-borne). Cosmesis was judged to be excellent in 12 patients, good in 15 patients, fair in 5 patients, and poor in 2 patients. Conclusion. In the patients reviewed, free flap reconstruction of the midface was completed in a single stage and created a reproducible, permanent separation of the oral and sinonasal cavities with adequate speech and swallowing. (J Prosthet Dent 2001;86:369-76.)

Recent innovations in the use of the radial forearm free flap

The radial forearm free flap is the most widely used free tissue transfer in head and neck reconstruction. This article reviews recent trends in the use of the radial forearm free flap for head and neck reconstruction. The use of the radial forearm free flap as an osteocutaneous free flap is advocated by some authors, although a relatively high rate of pathologic fractures have been reported in the past. Strategies to minimize these fractures are reviewed. Attention is also focused on the preoperative evaluation of distal arm vascular status, the minimization of donor site morbidity, and new innovations with respect to the use of this flap.

Sellection of Flaps for Cranio-Maxillo-Facial Reconstruction

Sellection of Flaps for head and neck, especially cranio-maxillo-facial reconstruction is determined by the following factors. Firstly, there is the recipient vessels or not. Secondary, there are the bone defect and/or soft tissue defect. Further, the prognosis of malignant tumor and the patient's general condition, age, sex etc are determine the best flap selection. We require the following peculiarities for the flap of cranio-maxillo-facial reconstruction. So called, three-dimensional maneuverability of the skin flap relative to the bone and the simplicity of bone trimming. The separated osteocutaneous scapular flap preserving the angular branch includes the ability to design multiple skin paddles (scapular, para-scapular, and ascending scapular flap) and two separated bone flaps (the lateral border and tip of the scapula) allowing improvment in three-dimensional spatial relationships for maxillary reconstruction. In addition, the scapular osteocutaneous free flap can be combined with such other flaps as the latissimus dorsi flap and the serratus anterior flap because the vascular supplies of these flaps also originate from the subscapular vessels. The essential elements of the maxillectomy defect are the body components of the hard palate, the anterior alveolar ridge, the anterior maxillary wall, and the medial nasal wall. Extending the defect into the orbit also entails loss of orbital rim, orbital floor, and medial nasal wall, and, occasionaly, the skin of the anterior cheek. We have performed maxillary reconstruction using the separated osteocutaneous scapular flap preserving the angular branch and the combined flaps with subscapular vessels. That is to say specifically, we use the lateral border of the scapula supplied by the periosteal branches of the circumflex scapular artery for reconstruction of the zygomatic body and anterior maxillary wall, and so the tip of the scapula supplied by the angular branch for reconstruction of the orbital rim and floor. The scapular or para-scapular flaps are used for reconstruction of the medial nasal wall or hard palate.

Increasing use of the scapula osteocutaneous free flap.

To determine the appropriate use of the scapula osteocutaneous free flap (SOFF) and to document donor site morbidity. Retrospective review and prospective physical therapy evaluation. A computer database of all free flap procedures performed at a single institution was created. Specific clinical and operative details from cases involving a bone flap were extracted from the database. Rates of usage of the various osteocutaneous flaps were compared over four successive 2-year intervals (1992-1999). A single physical therapist performed a structured evaluation of the donor site. Overall, 64 bone flap procedures were performed, of which 24 (37.5%) were SOFF procedures. The SOFF utilization has increased from 6.6% to 63.6%, while fibula and iliac crest utilization has fallen significantly. This is in part because of the greater versatility of the SOFF, with the possibility of separate skin paddles and adequate bone length. The mean cutaneous area harvested with the SOFF was 110 cm2 (range, 48-200 cm2) compared with 55.4 cm2 (range, 25-102 cm2) and 77.6 cm2 (range, 50-120 cm2) for the fibula and iliac crest, respectively. Mean bone flap lengths were 8.37, 7.65, and 10.1 cm, respectively, for the SOFF, fibula, and iliac crest. Dual skin paddles were used in 50% of the SOFF procedures versus 2.8% for the fibula flap procedures. There were no significant complications of the donor site in any patient, and there was only one flap failure (4.1%). Related to the SOFF, donor site morbidity was subjectively judged as "mild," for pain, mobility, and strength. There were no complaints of poor appearance of the donor site. Activities of daily living were judged as "not limited" or 'limited a little" in the majority of patients. Objective measurements of range of motion revealed an average reduction of 1 degree to 12 degrees in five different shoulder functions. Elbow and arm ranges of motion were not limited. Strength was minimally reduced in the shoulder, while the arm and forearm showed no reduction in strength. The SOFF is a versatile osteocutaneous free flap that can be used for a multitude of reconstructive problems. This and its relative lack of significant donor site morbidity have caused its use to increase significantly.

Bipolar Scissors in Facial Plastic Surgery

Many methods are available to the facial plastic surgeon for elevating and separating tissue, from cold steel to monopolar cautery to various laser-cutting technologies. Bipolar cautery has replaced monopolar cautery as the optimal hemostatic technique because of its decreased tissue damage and improved capabilities. Bipolar scissors concurrently offer a dissecting technique with hemostatic capability. Little exists in the otolaryngology literature on the use of bipolar scissors for soft tissue dissection. To describe our experience using bipolar scissors in a variety of facial plastic and reconstructive procedures. Tertiary care referral academic center. We retrospectively reviewed 78 procedures performed using bipolar scissors between June 1997 and August 1999. In facial plastic cosmetic surgery, bipolar scissors were used 31 times for deep plane face-lifts and 16 times for endoscopic browlifts. In facial plastic reconstructive surgery, bipolar scissors were used in 15 radial forearm free flaps, 10 fibula osteocutaneous flaps, 3 rectus abdominis free flaps, and 3 latissimus dorsi myocutaneous free flaps. In all procedures, bipolar scissors facilitated the dissection. By allowing for a drier field, less time was required to elevate the flap and obtain hemostasis. Complications were not increased compared with historical controls. In the harvesting of fibula osteocutaneous free flaps, use of bipolar scissors allowed harvesting without use of a tourniquet. Bipolar scissors, a new technology in facial plastic surgery, allow the same control as sharp dissection and provide simultaneous hemostasis.