A new design of the iliac crest microsurgical free flap without including the "obligatory" muscle cuff

The iliac crest free flap has undergone a gradual evolution to provide more functional and cosmetic oromandibular reconstructions. The soft-tissue cutaneous component has largely resisted refinement and currently constitutes the flap's principal drawback. Conventionally, the cutaneous vessel's soft-tissue encasement and a protective cuff of abdominal muscle are harvested to ensure skin perfusion. These protective measures, however, produce a bulky flap that is tethered to the bone and difficult to inset into complex three-dimensional defects. A series of anatomic and clinical investigations has confirmed that in 30 percent of individuals, the skin island can be elevated on a dominant cutaneous branch from the deep circumflex iliac artery. Harvesting the skin as an axial pattern flap greatly increases its independence from the bone, improving maneuverability. A small collar of abdominal muscle is incised around the pedicle, obviating the need for the customary 2.5-cm protective muscle cuff. Exclusion of the abdominal muscular component reduces the flap's volume, decreases the need for secondary debulking, and reduces the donor site morbidity.     

Damage to the inguino-femoral nerves in the treatment of hernias. An anatomical hazard of traditional and laparoscopic techniques

Laparoscopic techniques currently constitute an alternative proposed for the repair of hernias of the inguinofemoral region. Nerve injuries have led some teams to recommend technical principles based on the anatomical relations of these nerves with the subperitoneal fascia transversalis and inguinal fossae. An anatomical study consisting of dissection of nonembalmed cadavres, allowed, after evisceration, dissection of the lumbar plexus and its terminal branches, particularly those supplying the inguinofemoral region: iliohypogastric and ilio-inguinal nerves, the genitofemoral nerve, the femoral nerve and the lateral cutaneous nerve of the thigh. Via transperitoneal laparoscopy, the posterior surface of the anterior abdominal wall is centered on the deep inguinal ring, containing testicular vessels and the vas deferens. This deep inguinal ring receives the genitofemoral nerve. Medially, the anterior parietal peritoneum describes three folds formed by the outline of the epigastric artery, umbilical artery and urachus on the midline. The outline of Hesselbach's ligament separates the deep inguinal ring from Hesselbach's triangle, the zone of weakness of direct inguinal hernia. The iliac psoas muscle pass laterally underneath the inguinal ligament, while the external iliac vessels, subsequently becoming the femoral vessels, are located medially. Pectineal ligament lies on the posterior surface of the femoral ring between the umbilical artery and the epigastric artery. Installation of an abdominal wall prosthesis, either transperitoneally or retroperitoneally, must be centered on the deep inguinal ring, and its solid sutures are located medially to the pectineal ligament and anterior abdominal wall. On the other hand, the nerves at risk of being damaged are situated laterally: the ilio-inguinal and ilio-hypogastric nerves in the plane between external oblique and internal oblique above the anterior superior iliac spine, lateral cutaneous nerve of the thigh under the inguinal ligament close to the anterior superior iliac spine, genitofemoral nerve with the spermatic cord in the deep inguinal ring and femoral nerve underneath the inguinal ligament with the psoas muscle lateral to the external iliac artery. No stapling must be performed under the plane of the inguinal ligament to avoid damage to the femoral vessels and lateral to the deep inguinal ring to avoid nerve damage.     

Superior gluteal vessel as recipient for free flap reconstruction of lumbosacral defect

When the lumbosacral soft-tissue defect cannot be closed with a local flap, the option of a free flap should be considered. However, very few cases of free flaps have been reported, the reason being mainly difficulties in finding a suitable recipient vessel. Several vessels, such as inferior gluteal vessel, extension of thoracodorsal vessel with vein graft were reported as recipient vessels, but each one had its own drawbacks. The superior gluteal vessel has been used as a donor vessel in breast reconstruction after mastectomy but is thought to be undesirable as a recipient for microvascular anastomosis, mainly because of technical difficulty. From May of 1993 to March of 1997, five patients (one man and four women) received microvascular transfer of latissimus dorsi myocutaneous flaps using the superior gluteal vessel as a recipient. Their ages ranged from 11 to 64 years (mean 44 years of age). The causes of lumbosacral defects were tumor (1), trauma (1), radiation (2), and pressure sore (1). Before free flap transfer, the patients received an average of 2.8 operations for sacral lesions. Mean follow-up period was 12.4 months (2 to 40 months). A lateral approach was used to the superior gluteal vessel after elevation and retraction of gluteus maximus muscle. A thoracodorsal artery and vein were anastomosed to superior gluteal artery and vein in three cases, whereas in two cases, one artery and two veins could be anastomosed. All the flaps survived with complete recovery from sacral lesions. During the follow-up period, one case of partial skin graft necrosis and one case of a small superficial pressure sore developed, but there was neither dehiscence nor recurrence. The superior gluteal vessel is large in caliber, constant, with numerous branches, lying in proximity to the lesion, and relatively unaffected despite previous radiation. The technical difficulties with the deep location and short pedicle length can be overcome with some modifications in approach to the vascular pedicle. The superior gluteal artery and vein can be used as a recipient for the free tissue transfer when the lumbosacral defects cannot be covered with a conventional method.     

Variability of the obturator vessels

The obturator artery and vein are usually described as branches or tributaries of the internal iliac vessels although variations with connections to the external iliac or inferior epigastric vessels have been reported. Because these anomalous vessels are at risk in groin or pelvic surgeries that require dissection or suturing along the pelvic rim, we measured the frequency of these variations in 105 pelvic walls (45 in the United States and 60 in China). Our data show that 70-82% of pelvic halves and 83-90% of whole pelves had an artery, vein, or both in the variant position. Arteries were most often found in the normal position only but normal and anomalous veins were most frequently found together. These data show that it is far more common to find a vessel coursing over the pelvic rim at this site than not and have implications for both pelvic surgeons and anatomists.     

Variations in the relationship of the major vessels of the left coronary groove in the dog

The anatomic relationship of the 2 major vessels of the left coronary groove was studied in 140 dogs. Five basic patterns of disposition were observed: 1) circumflex artery superficial from its origin to the caudodorsal cardiac margin, coronary vein deep and not visible (22%); 2) coronary vein superficial from the ventral interventricular septum to the caudodorsal cardiac margin, circumflex artery deep and not visible (15%); 3) circumflex artery and coronary vein both superficial and running parallel with each other along the groove (8%); 4) coronary vein crossing circumflex artery at some point along the groove (44%); and 5) circumflex artery crossing coronary vein at some point along the groove (11%). These variations were found to influence certain experimental modifications of the left circumflex blood flow in the dog.     

Blood supply of the greater trochanter after trochanterotomy

The human vascular anatomy to the greater trochanter after a trochanterotomy (digastric, standard) was examined using injection techniques. Three major sources of blood supply to the greater trochanter were found: the proximal soft tissues, including the gluteus medius and minimus vascularized mainly from the internal iliac artery system; the distal soft tissues, including the vastus lateralis, vascularized from the descending branches of the lateral circumflex femoral artery; and a third possible source of blood circulation came from the transverse branch of the lateral circumflex femoral artery. Many vascular structures from the lateral circumflex femoral artery were concentrated in the anterior half of the vastus lateralis muscle. Perfusion with a latex oxide mixture and angiography after trochanterotomy proves that by using a digastric trochanterotomy, the transverse and descending branches of the lateral circumflex femoral artery to the greater trochanter thus can be preserved. With a standard trochanterotomy, the supply from the transverse and descending branches of the lateral circumflex artery are lost. These results therefore suggest that a digastric trochanterotomy is superior to a standard trochanterotomy because the blood supply of the trochanter is preserved.     

Functional alveolar ridge reconstruction with prefabricated iliac crest free flap and osseointegrated implants after hemimaxillectomy

We achieved functional alveolar ridge reconstruction after hemimaxillectomy using a prefabricated iliac crest flap. The iliac crest was vascularized secondarily by a long rectus abdominis muscle flap with its inferior epigastric vessels intact to obtain an ideal anatomic location between the maxillary defect and microvascular anastomosis site. The iliac crest was tightly resurfaced with a split-thickness skin graft as well. After a bony surgical delay, the prefabricated iliac crest flap was microsurgically transferred to the face. Three osseointegrated implants were placed in the prefabricated iliac crest, and a dental prosthesis was worn with immobilization and stability. Our procedure enabled recovery of a satisfactory facial appearance and excellent masticatory function.     

Comparison of two different delay procedures in a rat skin flap model

The overall objective of this study was to investigate how a strategic delay procedure could generate large flaps survival. On the basis of the vascular anatomy in 10 rats, a long three-territory skin flap spanning the length of the rat dorsum was designed. This flap was distally based on the deep circumflex iliac artery. The adjacent territories consisted of a large perforator of the posterior intercostal artery and the lateral thoracic artery in sequence. Two different vascular delay procedures were used and compared in nine animals. One dorsal midline incision was used to perform the two different delay procedures. The limited delay technique was performed by ligating a large cutaneous perforator of the posterior intercostal artery on one side of the rat. The extensive delay procedure was completed by ligating the cutaneous perforators of the posterior intercostal artery and the lateral thoracic artery on the other side of the rat. After a delay period of 10 days, the paired flaps were elevated, respectively, and sutured back in place. Seven days later, the area of viable skin flap was measured by the paper template technique. The animals were then killed, and the dorsal skin arteriograms were obtained by injecting a lead oxide mixture. Vascular changes of the paired flaps were assessed. In the extensive delay group, 100-percent survival was seen in four animals and distal partial necrosis was observed in five animals. The average survival area in the extensive delay group was 85.5 +/- 14.2 percent (mean +/- SD), whereas the flaps in limited delay group showed 100-percent survival in all animals (p < 0.05). In flaps that survived completely, the choke vessels among three vascular territories anastomosed throughout the flap. In the partially necrotic flaps, some choke and true anastomoses existed between the deep circumflex iliac and the posterior intercostal artery territories and the flap necrosis occurred in the third territory. This study suggests that the limited delay technique (ligation of one artery in the territory adjacent to the base of the flap) was the more effective delay procedure in the rat dorsal skin flap model.     

Reharvest of iliac crest donor site cancellous bone

Patients requiring cancellous bone grafting of an extensive deficit or multiple bone grafting procedures often lack a sufficient quantity of autogenous cancellous bone. Canine studies have indicated that a potential exists for reharvesting autogenous cancellous bone from an iliac crest donor site using a trapdoor harvesting technique. However, significant human experience with this procedure has been lacking. This report describes four patients who underwent successful reharvesting of an iliac crest donor site that provided clinically sufficient autogenous cancellous bone graft material to treat an ongoing or a new skeletal problem. These patients all met specific criteria regarding use of the trapdoor method of bone graft harvest and a minimum 24-month interval between bone grafting procedures. Preoperative computed tomography scanning of the iliac crest was useful in documenting that sufficient cancellous bone was available for reharvest. It appears that iliac crest donor site reharvesting is a specific advantage of the trapdoor technique and is a possible alternative to multiple site grafting or the use of allograft or bone substitute materials.     

Rotator cuff rupture. Vascular supply and collagen fiber processes as pathogenetic factors

Light and polarization microscopic appraisal of the pathways of fibers and blood vessels in the region of the rotator cuff shows branches of the suprascapular artery. These initially radiate into the insertion tendon parallel to the muscle fibers. They do not continue there, i.e. the vessel branches have blind endings, or they branch and anastomose with each other. Outliers of the transverse branch of the anterior circumflex artery of the humerus come from lateral (from the direction of the deltoid muscle). They pass from the bony insertion of the supraspinatus tendon into the tendon plate, but only run together with the fibers for a short distance. Consequently, a zone low in vessels or free of vessels can be constantly demonstrated under a magnifying glass in the course of the supraspinatus and to a small extent also of the infraspinatus in the fetus or neonate as well as in the adult in the region of the zone of interweaving of the tendinous muscle outlier with the capsule at length magnification. In the genesis of rotator cuff rupture, the presence of hypovascularity must be considered to be a predisposing factor which is present from birth onwards. It affects the clinical course during the process of aging as the point of least resistance in consequence of arteriosclerosis, collagen degeneration physiological wear and tear friction at the lower surface of the acromion and inflammatory swellings of the subacromial bursa.     

Comparative pathogenesis of human WA1 and Babesia microti isolates in a Syrian hamster model

The medial thigh flap is a perforator-based flap nourished with septocutaneous or muscle perforators originating from the femoral vessels. To date, 8 patients have been repaired with this flap and extended or connected flaps including this flap: 4 patients with lower leg defects and 4 patients with intraoral and neck defects. The advantages of this flap are (1) several pedicle perforators exist for this flap, which makes possible duplicated vascular anastomoses to establish reliable circulation of the transferred flap; (2) the flap can be extended or connected to other neighboring flaps in the anterior thigh, so that extensively wide defects can be closed in one stage; (3) the great saphenous vein can be simultaneously used as a vein graft or for venous drainage for the flap; (4) the anterior branch of the femoral nerve can be used for sensory potential; and (5) there is minimum morbidity of the donor defect and a large dominant vessel for the leg can be preserved. The suitable indications for this flap are defects after removal of skin cancer in the foot or lower leg and wide defects after resection of head and neck cancer, which can be reconstructed with the flap connected to neighboring skin flaps. The disadvantages of this flap are that it has a small, short vascular pedicle and the bulkiness of the flap's fatty tissue often requires thinning.     

Organization and structure of branches in the rat pulmonary arterial bed

Pulmonary arteries were fixed by perfusion under constant pressure and filled with rubber. The hardened rubber cast delineated the arterial bed, permitting dissection of axial vessels and all branches. Each segment was prepared for scanning electron microscopy and transmission electron microscopy. Branches arising at acute angles from the axial artery and the first two generations of its branches, regardless of diameter, had the same concentric muscle layer structure as parent vessels. Endothelial cells of the parent vessel were oriented into the ostia of these branches. Branches that came off the axial vessel or its branches at right angles had spiral muscle bundles and led to nonmuscular precapillary vessels. Right angle branches also had similar wall structure regardless of diameter. Near the ostia of right angle branches, endothelial cells of the parent vessels did not show orientation of their long axis into the branch lumens. It was concluded that branch arteries arising at acute angles are conduit which carry blood to distant parts of the lung while right angle branches are a histologically different group which distribute the blood to local capillary beds.     

Salvage angiogenesis induced by adenovirus-mediated gene transfer of vascular endothelial growth factor protects against ischemic vascular occlusion

PURPOSE: Vascular endothelial growth factor (VEGF) is a potent stimulator of angiogenesis, and transgene expression from adenovirus vectors can provide in vivo delivery of proteins. On the basis of this knowledge, we hypothesized that local administration of a replication-deficient adenovirus vector expressing complementary DNA for VEGF (AdVEGF) would induce collateral vessel formation in the setting of ischemia that could protect against subsequent acute vascular occlusion. METHODS: Hindlimb ischemia was induced in Sprague-Dawley rats by means of unilateral ligation of the common iliac artery immediately followed by administration of 4 x 10(9)-plaque-forming units VEGF, the control vector AdNull, or phosphate-buffered saline solution into the iliofemoral adipose tissue and thigh muscles. Untreated rats with common iliac ligation were used as an additional control group. RESULTS: Local VEGF expression was observed for 5 days in AdVEGF-treated rats but not in controls. Three weeks after ligation and vector administration, the ipsilateral femoral artery was ligated for a model of an acute vascular occlusion in the setting of preexisting ischemia. Blood flow to the ischemic hindlimb relative to the contralateral hindlimb evaluated with color microspheres demonstrated significantly increased blood flow in the AdVEGF-treated rats compared with each control group (p < 0.0001). Relative blood flow assessed by means of 99mTc-sestamibi radionuclide scans also demonstrated increased blood flow to the ligated hindlimb of AdVEGF-treated rats compared with each control group (p < 0.002). AdVEGF-treated rats also demonstrated increased vascularity in the ligated limb compared with each control group as assessed by means of angiography (p < 0.0001) and histologic quantification of blood vessels less than 80 microm diameter in local adipose tissue and capillaries per muscle fiber (p < 0.0002). AdVEGF treatment prevented a rise in femoral venous lactate femoral venous concentrations 1 hour after femoral artery ligation in control rats (p < 0.04). CONCLUSIONS: An adenovirus vector expressing VEGF complementary DNA is capable of stimulating an angiogenic response that protects against acute vascular occlusion in the setting of preexisting ischemia, suggesting that in vivo gene transfer of VEGF complementary DNA might be useful in prophylaxis of advancing arterial occlusive disease.     

Approaches to study of ischemia in bone

Ischemic osteonecrosis is a complication of certain traumatic and a number of idiopathic conditions. The course of the disease may result in collapse of the convex member of a joint and osteoarthritis, often requiring arthroplasty. Increasing incidence in young adults poses a challenge for development of long-term joint prostheses. Current status of research into the disease is discussed and three new models using intravital microscopy described. The first, an arterial occlusion (AO) model, creates ischemia by occluding the common iliac artery exclusively, avoiding direct trauma on other tissues in the limb. The second, a total occlusion (TO) model utilizes classical tourniquet occlusion of the thigh vessels. The third, a venous occlusion (VO) model, is also a tourniquet procedure but it blocks occlusion of the femoral artery with a protective sheath. Preliminary results from AO and TO studies are reported which show that reperfusion injury is detectible after ischemia doses as short as 4 h. This complication was confirmed by observation of leukocyte adherence, secondary ischemia, and abnormal vessel leakage. Also, a new quantitation of osteonecrosis is introduced whereby fluorescently-tagged dead osteocytes and computer-based image processing provide values for an "osteonecrosis index." Viewing of all vascular events is made possible by intravital microscopy through a bone chamber window implanted in rabbit tibias. It is proposed that such chronic visual techniques allow quantitation of events leading to osteonecrosis as well as the revascularization, resorption and bone apposition of creeping substitution which characterizes postischemia recovery.     

Superficial ulnar artery originating from the brachial artery and its clinical importance

We found a left superficial ulnar artery in the cadaver of a Japanese woman. This anomalous vessel originated from the brachial artery at a site 55 mm distal to the inferior border of the teres major muscle and medial to the median nerve, ran downward and medially superficial to the forearm flexor muscles, and then downward to enter the hand. It formed superficial and deep palmar arches with the radial artery. The clinical importance of the anomalous ulnar artery is discussed.     

Injuries to arteries during osteosynthesis of the femur

Three patients were operated upon for a damage of the main vessels with a pin during osteosynthesis of the femoral bone. Two patients had a wound of the femoral vessels resulting from using the Ilizarov apparatus. The third patient had an injured external iliac artery during synthesis of the femoral neck with a nail. The main symptom of the injured femoral artery was hemorrhage from the pin canal in soft tissues. In two cases perforations in the vascular wall were sutured and in one case angioplasty was performed thrice without a success and was completed by ligation of the superficial femoral artery.     

Long-term effects of pentobarbital anesthesia on the atrial natriuretic peptide system in rats

The midline fascial splitting approach is a modified midline approach to the iliac crest for bone graft that takes advantage of the anatomic planes between layers of the dorsal lumbar fascia. Two hundred consecutive grafts were taken by this technique with one superficial infection, two cases of serous hematoma, and three patients with significant postoperative pain at the harvest site, for an overall complication rate of 3%. In comparison, bone grafts were harvested from 200 consecutive patients by the midline subcutaneous approach to the iliac crest with 2 deep infections, 1 cluneal nerve injury, 15 patients with severe and disabling pain at the harvest site, and 12 patients with a serous hematoma, for an overall complication rate of 15%. The midline fascial splitting approach significantly reduced the incidence of postoperative serous hematoma (P < 0.007) as well as the incidence of significant and disabling pain (P < 0.001). In addition, the approach is simple, straightforward, anatomic, and decreases trauma to soft tissues.     

Coordinated induction of plasminogen activator inhibitor-1 (PAI-1) and inhibition of plasminogen activator gene expression by hypoxia promotes pulmonary vascular fibrin deposition

PURPOSE: In a rabbit model, transposition of a muscle pedicle flap to an ischemic hind limb has been shown to result in the development of new blood vessels that connect the arterial circulation of the flap to the circulation of the limb. The hypothesis that exogenous recombinant basic fibroblast growth factor (bFGF) would enhance the development of this new blood supply was examined and the regulation of bFGF in this process was investigated. METHODS: The right common iliac artery was ligated in 12 male New Zealand white rabbits. An abdominal wall muscle flap based on the left inferior epigastric artery was transposed to the right thigh. bFGF in phosphate-buffered saline (PBS) at 3 ng/h (n = 6), or PBS alone (n = 6), was infused for 7 days via mini-osmotic pumps with an infusion catheter positioned at the flap-muscle interface. The flap-muscle interface was immunostained with anti-alpha-actin antibody to determine blood vessel density (number of vessels/mm) and with anti-bFGF antibody to evaluate bFGF distribution. RNA was isolated from these sections, and polymerase chain reaction (PCR) was used to examine endogenous bFGF messenger RNA (mRNA) expression. RESULTS: Blood vessel density was significantly increased in animals receiving exogenous bFGF (22. 0 +/- 10.6 vessels/mm vs. 10.7 +/- 8.8 vessels/mm, P =.009). In the controls, neovessels were arranged in clusters with endogenous bFGF concentrated around these clusters. In bFGF-treated animals, vessels were diffusely scattered throughout the flap-limb interface, corresponding to the distribution pattern of infused bFGF. There was no difference in bFGF mRNA expression between the control and the bFGF-treated groups. CONCLUSION: Exogenous bFGF infusion significantly augmented new blood vessel development at the flap-limb interface. Endogenous bFGF was up-regulated around the newly developed microvessels in control animals, and vessel growth correlated with the diffuse distribution of exogenous bFGF, implicating bFGF as an important factor in angiogenesis. Exogenous bFGF did not affect bFGF mRNA expression, suggesting that the regulation of bFGF is not under autocrine control.     

Adult onset of the Dandy-Walker syndrome

OBJECTIVE: We describe the CT findings of medial transfer of a sartorius muscle flap, which is done to protect the femoral blood vessels after radical inguinal lymphadenectomy for cancer or surgical debridement of infected femoral vascular grafts. MATERIALS AND METHODS: We reviewed the appearances and initial interpretations of 33 CT studies in 17 patients who underwent medial sartorius flap transfer after either (1) inguinal lymphadenectomy for melanoma or penile cancer or (2) debridement of infected groin wounds complicating vascular reconstruction of the femoral arteries. Muscle flap transfer was defined by the surgical record as either complete or incomplete. In complete sartorius muscle transfer, the proximal end of the muscle is dissected from the anterior superior iliac spine, rotated along its long axis, and sutured medially to the inguinal ligament. In incomplete transfer, the muscle it mobilized and stretched medially, and its medial border is fixed to the inguinal ligament and deep tissues. Clinical correlation and follow-up examinations were done for all patients, and CT reevaluation at intervals was done in nine patients. RESULTS: Complete sartorius flap transfer resulted in a mass anterolateral or anterior to the femoral vessels on postoperative CT scans in 20 studies; five of these masses were misinterpreted initially as possible recurrent metastatic lymphadenopathy, infection, or hematoma. Incomplete sartorius flap transfer resulted in bandlike stretching of the muscle over the femoral vessels in 13 studies. CONCLUSION: Medial transfer of the sartorius muscle causes a variable appearance of the groin on CT scans. The findings on CT scans after complete sartorius flap transfer should be distinguished from recurrent lymphadenopathy and from postoperative phlegmon or hematoma.     

Arteries and veins behind the thoracic vertebrae with special reference to the cutaneous blood supply

One thousand and thirty eight dorsal cutaneous vessels, which emerged onto the superficial fascia behind the thoracic vertebrae, were examined with regard to the point at which they perforated the fascia, their diameters, intermuscular courses and origins. Large vessels (more than 1 mm in diameter) were mainly distributed at the T1-T4 level. The intermuscular courses could be classified into three groups: a descending scapular course arising from the transverse cervical vessels (4.0%), a nerve-accompanying vertebral course (68.6%) and a deep vertebral course arising from other origins (27.4%). Vessels with a nerve-accompanying course ran through the middle sized (3-4 vertebral segments long) semispinalis muscle slips and descended over 1-2 vertebral segments. Vessels with a deep vertebral course, including the posterior external vertebral venous plexus, were located around the rotatores muscle. Vessels with a deep vertebral course as well as those following a nerve-accompanying course frequently emerged onto the fascia with a nerve since the former merged into the nerve-accompanying vessels immediately before perforating the fascia. The potential clinical applications of these results are discussed.