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Geoffrey G Hallock

Publications and source records attributed to Geoffrey G Hallock.

48 records · Page 3Linked to original sources
PubMed2003

The gracilis (medial circumflex femoral) perforator flap: a medial groin free flap?

The superior medial thigh skin territory has previously been successfully transferred as a free flap as part of a gracilis musculocutaneous flap. However, muscle bulk can be avoided and its function preserved by instead retaining only the musculocutaneous perforators arising from the gracilis pedicle like in a true perforator flap. A clinical example of this new perforator flap is described as the gracilis (medial circumflex femoral) perforator flap. This could become an ideal skin flap because no muscle is included, a well-defined segment of skin can be reliably harvested, closure of the donor site leaves a scar in the groin that can be readily concealed, and its dominant vascular pedicle is consistent in location and already familiar to most reconstructive surgeons.

Accidents, Occupational↗
PubMed2003

A vertical midline scar is a 'high-risk' factor for maximum survival of the rat TRAM flap.

The presence of any abdominal scar, in addition to obesity, a smoking history, and prior irradiation are considered the major known "risk factors" for predictable success or failure of the lower transverse rectus abdominis musculocutaneous (TRAM) flap. For many, a vertical midline scar has even been considered to be a relative contraindication. The possibility that the scar instead could effect some form of delay or by neovascularization permit reperfusion across the midline might negate this concern. The validity of this hypothesis was tested in 40 Sprague-Dawley (CD) rats using our standard rat TRAM flap model. Every rat initially had a vertical skin incision made from xiphoid to pubis. At a second stage, either immediately or after a delay of 1 week, 2 weeks, or 6 months, a superior-pedicled (dominant) or inferior-pedicled (nondominant) TRAM flap was raised, with five rats in each subgroup. For the inferior-pedicled group, the percentage of ipsilateral (muscle-pedicle half) flap survival approached 75% and had a trend toward greater survival with each increase in the time of delay, but any difference was not statistically significant (F= 0.653, P = 0.538). In the superior-pedicled group, the ipsilateral half of the flap always survived completely. In both groups, the contralateral or opposite side always underwent complete necrosis regardless of pedicle orientation or time constraints. The midline scar did not enhance even unilateral TRAM flap survival when compared with historic controls, and long-term transmidline reperfusion across the scar did not seem to occur. These findings corroborate the clinical observation that only a unilateral TRAM flap would be reliable in the presence of a vertical midline abdominal scar.

Animals↗
PubMed2003

Venous "supercharging" augments survival of the delayed rat TRAM flap.

Adequate delay of a pedicled transverse rectus abdominis musculocutaneous (TRAM) flap might not necessarily require interruption of the venous system. The retained ipsilateral deep vein of the dominant pedicle could then be used as a secondary outflow source for potential salvage of a congested flap. A venous "supercharged" rat TRAM flap model has been designed to evaluate the efficacy of this maneuver. Seventy-two female Sprague-Dawley rats (CD) were equally divided into two major groups, differing only in whether a delay by division of the dominant cranial epigastric artery had first been performed. An inferior-based TRAM flap (nondominant) was raised for each rat, with three subsets of 12 rats in each group, ie, with the cranial epigastric vein subsequently divided (group control), retained (supercharged), or retained but the inferior pedicle divided (venous flap). Both supercharged subsets had significantly augmented flap survival when compared with flaps in their group raised without the cranial epigastric vein, whether a delay maneuver had (96 +/- 6% vs 89 +/- 7%; P = 0.012) or not (80 +/- 8% vs 65 +/- 21%; P = 0.034) been performed. Flaps with only a cranial epigastric vein pedicle totally necrosed, implying that the observed enhancement in flap viability was not the result of transformation into a venous flap, but perhaps as a crossover flap where an adjacent venosome was captured. Venous supercharging can be accomplished by inclusion of the ipsilateral dominant deep vein, and should be a consideration in the clinical planning of delay maneuvers and for treatment of the compromised TRAM flap.

Animals↗
PubMed2003

Muscle perforator flaps: the name game.

The creation of a consistent nomenclature for muscle perforator flaps is essential not only to eliminate confusion in the literature, but also to facilitate their surgical application. Universal acceptance demands that the chosen system be as simple as possible, yet remain comprehensive and flexible enough to anticipate future adaptations. Flaps named by anatomical region alone can be ambiguous due to the frequent variations in perforator origin and sometimes multiple or overlapping "mother" vessels, which unfortunately is an inherent characteristic of muscle perforator flaps. One sensible solution is an appellation that includes both the involved muscle and its source vessel, in any order, eg. "source vessel(MUSCLE)" or "muscle(SOURCE VESSEL)" perforator flap. Such a combination immediately readily identifies the precise anatomical location of the flap, as well as stating exactly which vascular pedicle must be dissected.

Graft Rejection↗
PubMed2003

The medial circumflex femoral (gracilis) local perforator flap--a local medial groin perforator flap.

The medial circumflex femoral(GRACILIS) perforator free flap has been previously used to capture the superior medial thigh skin territory. This can also be valuable as a local flap, especially for adjacent groin wounds that are not uncommon after vascular interventions. Uncomplicated healing without vascular compromise was achieved using this as a local flap in 4 recent cases. Because the gracilis muscular branches can be independently dissected from the musculocutaneous perforators, the muscle itself can be separately included to form a combined conjoint flap, where the muscle is specifically only used to wrap around and protect any exposed vascular structures while the cutaneous component simplifies skin wound closure. The axis of rotation of the medial circumflex femoral perforator local flap extends throughout the groin region and potentially to the lateral thigh. This is an ideal local perforator flap because the source pedicle has a consistent location already well known to most plastic surgeons, the boundaries of the potential skin territory are reliable and well defined, and the scar from closure of the donor site within the medial groin can be readily concealed by clothing.

Femoral Artery↗
PubMed2002

Sagittal split tibialis anterior muscle flap.

The potential use of the tibialis anterior muscle as a vascularized flap requires consideration of some function preservation technique because this is not an expendable muscle. A direct longitudinal vertical or partial sagittal split of this muscle will allow coverage of mid-tibial defects without impairing function. This is a valuable alternative for small defects, especially if the muscle is already exposed in the wound. The muscle must be malleable enough to allow stretching over the tibia, because otherwise posteromedial undermining (as used in the medial- hinged anterior turnover version) would be necessary to obtain the desired reach. This as a variation of the latter, if possible, not only is more expedient to implement but also better preserves the microcirculation of the muscle to ensure viability.

Aged↗
PubMed2002

Facial reconstruction using a combined flap of the subscapular axis simultaneously including separate medial and lateral scapular vascularized bone grafts.

With the better understanding of the blood supply to the scapula, combined flaps of the lateral scapula along with the latissimus dorsi and/or serratus anterior are well known. The medial border of the scapula, in this respect, has been underused. The authors present a case report in which a conjoined combined free flap consisting of four free tissue transfers based on the subscapular axis was used in simultaneous reconstruction of a gunshot wound to the face. This included a medial scapular osteofasciocutaneous flap for the mandible, a lateral scapular osseous flap for the anterior maxilla, a serratus anterior muscle flap for the cheek, and a separate latissimus dorsi musculocutaneous flap for the forehead. This flap was successful and provides another alternative to the resolution of complex problems needing multiple areas of both soft-tissue coverage and vascularized bone graft.

Bone Transplantation↗
PubMed2002

The utility of both muscle and fascia flaps in severe upper extremity trauma.

BACKGROUND: Severe isolated upper extremity injuries are rarely lethal; however, they invariably are resource intensive, create significant disability, and promote resistance to a return to gainful employment. Appropriate soft tissue restoration is an essential component of any treatment protocol, and often requires a vascularized flap to protect the superficial neurovascular and musculotendinous structures. A basic schema to facilitate flap selection in the upper extremity is introduced. METHODS: The role of local muscle and fascia flaps or free tissue transfers for severe upper extremity injuries was retrospectively reviewed from a two-decade experience. Excluding digital injuries, primary treatment of soft tissue traumatic wounds requiring some form of vascularized flap occurred in 33 limbs in 31 patients. The choice of flap donor site, type, specific complications and benefits as related to the severity of injury, and the effect of timing of wound closure were compared. RESULTS: Initial coverage after significant upper extremity trauma in these 33 limbs required 16 local fascia flaps, 22 free flaps, 1 multistaged distant pedicled flap, and 1 local muscle flap. Flaps were selected in a nonrandom fashion on the basis of wound location, severity of injury, and flap availability. Complication rates were similar for local fascia and free flaps. The upper extremity could be divided into three regions that were differentiated according to the observed incidence of flap preference. Free flaps were more commonly used for hand and wrist wounds, or anywhere the defect was moderately large in size or extremely severe in overall injury. Local fascia flaps were a simpler option most applicable for the central upper limb. Local muscles as flaps were intentionally avoided to minimize any functional derangement. CONCLUSION: A schema to guide flap selection for upper extremity coverage is introduced that is predicated on using the best available option. The shoulder girdle and axilla are reached by many local trunk muscle or fascia flaps. The central upper limb about the elbow often is conducive to coverage with specific local fascia flaps. The distal upper extremity may be best served by a free flap, as would any large wound in all upper limb regions.

Activities of Daily Living↗
PubMed2002

The relative importance of the deep and superficial vascular systems for delay of the transverse rectus abdominis musculocutaneous flap as demonstrated in a rat model.

The use of some form of delay maneuver for "high-risk" patients before transfer of the superior pedicled lower transverse rectus abdominis musculocutaneous (TRAM) flap for breast reconstruction has augmented the rate of success in both the experimental and clinical arenas. A common method of vascular delay has been the bilateral division of both the superficial inferior epigastric and deep inferior epigastric vessels. Whether all of these must be divided to adequately effect the delay is unknown. For that matter, the relative importance of the superficial versus the deep vascular systems is unclear. To investigate this uncertainty, a delay was attempted in 61 Sprague-Dawley rats by division of either the superficial inferior epigastric or deep cranial epigastric vessels (the latter is the homologue to the human deep inferior epigastric) in unilateral or bilateral fashion. Division of the contralateral superficial inferior epigastric vessel resulted in significantly greater TRAM flap survival than either ipsilateral or bilateral superficial inferior epigastric vessel division (p = 0.0034 or p = 0.0093, respectively). Division of the ipsilateral or bilateral deep cranial epigastric vessel resulted in significantly greater flap survival than just contralateral deep cranial epigastric vessel division (p = 0.0034 or p = 0.006, respectively). No significant difference was observed between the group having contralateral superficial inferior epigastric or groups with ipsilateral deep cranial epigastric division, implying that either alone would be efficacious to achieve the desired delay effect. This would allow the other vascular system to be retained intact for later potential salvage maneuvers as needed.

Animals↗