Use of a microvascular coupler for repair of major distal upper extremity artery injuries.

BACKGROUND: Non-suturing alternatives to expedite a microanastomoses while still insuring maximum patency rates to date have best been achieved using everting ring-pin devices. Although these so-called couplers have heretofore primarily been used for the venous microanastomosis during free flap transfers, they have also had limited value for their arterial counterpart. METHODS: Applications for use of the microanastomotic coupler has been extended to repair solitary arterial injuries in the distal upper extremity. Over the past year, 4 patients specifically with hand or forearm arterial injuries alone, had rapid coupling of the injured vessels. RESULTS: Direct end-to-end repair of all hand or forearm arterial injuries using a microanastomotic coupler was possible in 3 of four cases. Because of the greater extent of injury, the exception required an interposition vein graft; but that too was coupled to each end of the divided artery in end-to-end fashion. In no case was there any compromise of vascular patency. CONCLUSION: Although hand perfusion in no individual in this series was ever at jeopardy because of persistent collaterals, this demonstration of the efficiency and efficacy of this device may justify future use for critical limb revascularisation.

Preservation of lower extremity amputation length using muscle perforator free flaps.

Coverage of any lower extremity amputation stump must be durable to resist external forces, well contoured, and thin enough for proper shoewear or prothesis fitting. Preservation of bone length to maximise the ability to ambulate is also of paramount importance. If local soft tissues are inadequate to fulfil these prerequisites, consideration of a microsurgical tissue transfer is a reasonable option, especially to cover bone or save a major joint. Muscle perforator free flaps, as shown in this series of eight patients using four different donor sites, are a versatile alternative for the necessary soft tissue augmentation. Multiple choices are available and often even from the involved lower extremity to minimise further morbidity. The vascular pedicles of this genré of flaps are relatively exceedingly long and of respectable calibre to facilitate reaching an appropriate recipient site. They can be sensate if desired. Of course, muscle function is by definition preserved. Complications are minimal and usually related to the reason for the amputation in the first place.

A history of the development of muscle perforator flaps and their specific use in burn reconstruction.

Only rarely does coverage in the burn patient require the use of a vascularized flap. However, when mandatory, a knowledge of all alternatives is essential because common donor sites may have been badly burned and unavailable. The recent development of the muscle perforator flap may prove to be another valuable option. These flaps are nourished by the familiar musculocutaneous perforators but differ in that their complete intramuscular dissection is required during flap elevation so that no muscle need be included with the flap. A review of six cases using muscle perforator free flaps specifically for burn reconstruction or rehabilitation demonstrates how the same large cutaneous territory of a musculocutaneous flap can still be captured while the muscle and therefore its function is preserved.

Anatomic basis of the gastrocnemius perforator-based flap.

The gastrocnemius muscle is rarely considered today as a musculocutaneous flap. Yet, the posterior calf skin by itself can still be used to advantage as a source of local or perhaps free flaps. Fascial perforators in this region were reexamined in an anatomic study in 10 fresh cadaveric specimens to investigate the possibility of a gastrocnemius muscle perforator-based flap. At least two substantive perforators were found in all limbs, and there was always one overlying the medial gastrocnemius muscle (overall mean, 4.0 +/- 1.8 perforators; range, 2-7 perforators). The origin of these perforators in any given specimen was most commonly as a secondary branch from the medial or lateral sural arteries alone (60%), from the median sural artery as a direct cutaneous branch alone (10%), or from either of the muscle pedicles and/or the median sural artery (30%). Thus, in 90% of limbs, the potential for elevating a gastrocnemius perforator-based flap exists without the need for any muscle sacrifice. Otherwise, a more traditional posterior calf fasciocutaneous flap was possible. Other deeper intramuscular collaterals were also identified so that sequential use of the muscle as a separate flap does not seem to be compromised.

Physiological studies using laser Doppler flowmetry to compare blood flow to the zones of the free TRAM flap.

Physiological studies of in vivo blood flow within the various types of lower transverse rectus abdominis musculocutaneous (TRAM) flaps have been limited. Therefore, to supplement our knowledge, intraoperative measurements of flow to the cutaneous paddle as derived from laser Doppler flowmetry were recorded in 13 free TRAM flaps in 10 patients (3 bilateral). The relative contributions from both the deep inferior epigastric artery (DIEA) and the superior epigastric artery (SEA) to each zone were assessed jointly and then independently. Mean flow via the DIEA contribution alone was equal to or greater than twice that of the SEA in all zones, although this was not significant (p = 0.079). Flow from either the DIEA or the SEA diminished the farther the zone was from the source pedicle. Contralateral skin territories had significantly decreased flow when compared with all ipsilateral territories (p = 0.005), so that a relative ischemia exists even in free TRAM flaps, which could be the source of unexpected partial flap loss and/or fat necrosis in these zones. These findings were consistent with anatomic descriptions of the lower TRAM flap that imply that the DIEA is the dominant source vessel to the skin of this region.

A prospective study of the accuracy of the surgeon's diagnosis and significance of positive margins in nonmelanoma skin cancers.

Even with a precise preoperative diagnosis, complete excision of nonmelanoma skin cancer is not always achieved. The conundrum remains the decision for appropriate secondary treatment. Many surgeons, regardless of the nature of the lesion, consider re-excision to be the only option. In a prior 4-year prospective study that ascertained the accuracy of our clinical diagnosis of skin lesions removed in an office setting, one-fifth were found to be malignant and 98 percent (n = 415) of the lesions were nonmelanoma skin cancer. Unfortunately, 65 (15.7 percent) of the malignant nonmelanoma skin cancer lesions had positive margins. The outcome of our management for these specific lesions was followed prospectively over the 7.5 years of this study to determine whether aggressive surgical intervention was justified in every case. Of 65 patients with lesions, early and complete re-excision of margin-positive nonmelanoma skin cancer was performed for 34 (52.3 percent), with residual tumor found in 11 (32.4 percent), followed by a later recurrence in one (2.9 percent). The remaining 31 patients agreed to semiannual office visits, with one (3.2 percent) recurrence in this group. Thus, the overall rate of recurrence for margin-positive nonmelanoma skin cancer was 3.1 percent, with a mean follow-up of 3.6 years (range, 0 to 7.5 years). There were no recurrences for basal cell carcinoma in either treatment group, suggesting that, at least for "simple" primary lesions without confounding risk factors, there is some validity to a "wait and see" attitude, in which treatment of a potential recurrence would be straightforward. Despite our observed infrequent local recurrences of squamous cell cancers (13.3 percent), the small risk of metastases still suggests the appropriateness of complete surgical eradication for these tumors whenever feasible.

Expanded applications for octyl-2-cyanoacrylate as a tissue adhesive.

The commercial introduction of octyl-2-cyanoacrylate as a medical-grade tissue adhesive was intended to be a rapid, painless, suture-free method for closure of simple lacerations and surgical wounds. The efficiency and therefore potential economic advantage of this material has led to further investigations of other possible indications. This glue has now been used in more than 100 different occasions for "off-label" applications including nailbed repair, skin graft fixation, temporary otoplasty, wound sealant, and other forms of wound closure. Complications are virtually nonexistent, and there has been no evidence of histotoxicity. The role of this material as an important reconstructive tool has not yet been delineated completely, but it appears to have no contraindications if used sensibly.

The fate of the failed second-attempt free flap.

The superiority of a free flap in many clinical situations is unparalleled and, fortunately, initial failure rates have become almost nonexistent. Nevertheless, failures do occur, and then often an attempt at a second free flap transfer is the only worthy alternative for the same reason. In the author's experience during the past two decades, a second attempt was indicated after the failure of 19 free flaps. There were two distinct groups. Intraoperative failure was recognized for eight flaps and a second free flap was attempted immediately, with a 50% success rate. The rest were redone on a delayed basis, with 63.7% successful-a rate that was not statistically different from the first group. There were eight second failures (42.1%) overall. The need for vein grafts was the only notable factor associated with a higher risk for second flap failure (seven of eight failed second flaps). The ultimate fate of failed flaps was dismal, in that three required limb amputations and two have had unstable wounds for more than 15 years. This morbidity vindicated the difficult decision to undertake a second free flap attempt, which never can be taken lightly. Because successful flaps avoided these problems, an aggressive approach is emphasized, including an immediate second free flap attempt if conditions are favorable.

Comparison of a new method for computer analysis with standard techniques for measuring survival rates in the rat transverse rectus abdominis musculocutaneous flap.

Many methods have been used to measure experimental flap survival in animal models. These have previously included planimetry, computer programs, and (routinely by the authors) the simple measurement of the weight of a template traced according to the dimensions of a given flap. To test the validity of their method, an alternative technique was developed by the authors' biostatiticians. Initially, in a study of rat transverse rectus abdominis musculocutaneous (TRAM) flaps, all templates were also scanned electronically to form bitmaps. Using commonly available software programs, each bitmap was colorized corresponding to viable and nonviable areas of the flaps. A summation of individual pixels by color could then be used to calculate the percentage of flap survival. A comparison of both methodologies in 64 rat TRAM flaps found that the survival rate was slightly greater overall when a computer analysis had been performed (3.1 +/- 1.7%), but this was not a significant difference (p = 0.479). Thus, the previous standard method was proven reliable, but just as precise calculations are now possible using the convenience of any personal computer.

Impact of the successful flap but failed reconstruction on the true rate of success in free-tissue transfers.

Extraordinarily high success rates for free-tissue transfers are now virtually the norm. Unfortunately, expectations to consistently obtain similar outcomes, without a familiarity with the incidence of associated adverse sequelae, place microsurgeons in a potential quandary. A "true success" rate should consider not just those immediately viable flaps with patent microanastomoses, but should discount cases in which there is significant partial flap loss, or persistence or recurrence of the original indication for the free-flap transfer, including the need for delayed amputation of an extremity. An estimate of the impact of the latter phenomena in redefining success rates has been derived from the author's experience with 156 free flaps over the past decade. There was overt failure in 12 flaps, for a stated success rate of 91.7 percent. However, on closer scrutiny, including the above negative criteria, successful flaps yet failures occurred in an additional 16 flaps, so that the true rate of success was a more realistic 81.4 percent. An even more difficult assessment that was not quantified is the reality of functional failures, despite successful microsurgery, which could lower this number even further.

Octyl-2-Cyanoacrylate adhesive for rapid nail plate restoration.

Following nail bed repair, returning the nail plate as a conforming stent or splint is a common technique. Especially when split, the nail plate fragments can very readily be pieced together and bonded to the nail bed using the tissue adhesive Octyl-2-Cyanoacrylate. This new formulation can expedite this maneuver, and has shown no signs of histotoxicity or adverse effect on nail plate regeneration.

Both superficial and deep extremity veins can be used successfully as the recipient site for free flaps.

Many controllable factors can influence free flap success rates, including the choice of recipient vessels, which can be as crucial as selecting the optimum donor site. The extremities are unique in that their dual venous systems offer an even greater diversity of options and perhaps risks. Whether the superficial as well as the more conventional deep veins can be used successfully as the recipient vein site is an important question analyzed in this retrospective, nonrandomized, yet inclusive review of 102 free flaps from the past decade used only for extremity defects. During this 10-year period, 144 venous microanastomoses, including 41 using superficial recipient veins, were utilized for these 102 flaps. There were 10 anastomotic catastrophes (9.8%): half were venous in origin and four fifths were salvaged by prompt reexploration. Only one venous thrombosis, and that in the deep system, resulted in flap failure. All arterial problems in every patient resulted in total flap loss, so that overall there was a 94.2% flap success rate. The overall incidence of complications and flap failure when the deep vein was the recipient site was 9.6% and 5.5% respectively. For superficial veins it was 15.4% and 7.7%, and, if used in a combination for dual venous outflow, the incidence was 6.3% for either category. There was no significant difference in these rates between groups, and in the vast majority of cases either the deep or superficial venous systems could indeed be used successfully as the recipient vein for microvascular tissue transfers.

Utility of both muscle and fascia flaps in severe lower extremity trauma.

BACKGROUND: The evolving technology in trauma management today permits salvage of many severe lower extremity injuries previously even considered to be lethal. An essential component for any such treatment protocol must be adequate soft tissue coverage that often will use vascularized flaps. Traditionally, calf muscles have been used proximally and free flaps for the distal leg and foot. The reintroduction of reliable local fascia flaps has challenged this dictum, proving to be a simpler and yet versatile option. MATERIALS AND METHOD: The role of both muscle and fascia flaps in lower extremity injuries has been retrospectively reviewed from a 2-decade experience. Soft tissue deficits requiring some form of vascularized flap occurred in 160 limbs in 155 patients. The frequency of use of flap types, specific complications and benefits, effect of timing of wound closure, and rate of limb salvage were compared. RESULTS: Initial coverage after significant lower extremity trauma in these 160 limbs required 60 local muscle flaps, 50 local fascia flaps, and 74 free flaps. These flaps had been selected on a nonrandom basis according to wound location, its severity, and flap availability. Complications were directly related to the severity of injury, and for free flaps as a group (39%), although these were not independent variables. Local muscle (27%) or fascia flaps (30%) were similar with regard to this morbidity. Healing was more likely to be uneventful if coverage were accomplished during the acute period after injury, regardless of flap type. Muscle flaps were still used in two thirds of all cases, with the soleus muscle used as often for the distal leg as the mid-leg. Local fascia flaps were most valuable for smaller defects, especially in the distal leg or foot, and often as a reasonable alternative to a free flap. CONCLUSION: The traditional role of the gastrocnemius muscles for flap coverage of knee and proximal leg defects and the soleus muscle for the middle third of the leg was reaffirmed. The soleus muscle often also reached distal leg defects as could local fascia flaps, where classically, otherwise, a free flap would have been necessary. The largest or most severe wounds, irrespective of limb location, required free flap coverage. Local fascia flaps proved to be a valuable alternative.

The increase in TRAM flap survival after delay does not diminish long term.

The delay phenomenon is sometimes relied on to increase survival of the transverse rectus abdominis musculocutaneous (TRAM) flap in high-risk patients. TRAM reconstruction has then been performed traditionally 1 to 2 weeks after the delay procedure. The optimum time course from this surgical delay to flap elevation, as it relates to survival, has not been well studied--specifically whether the potential benefit of delay lessens at any particular time after the delay procedure. The authors examined the effects of varying time periods (up to 7 months) after delay, via division of the dominant bilateral superior epigastric vessels, on the viability of the TRAM flap in a rat model. TRAM flap survival improved significantly (p < 0.01) at all time points in delayed groups compared with a nondelayed control group. The benefit of delay in this model was maintained at all times, even long term. In conclusion, it may be possible to extend the delay period safely beyond the customary 1 to 2 weeks without compromising survival of the TRAM flap, which may prove to be more convenient.

Simplified nomenclature for compound flaps.

The unique niche for compound flaps is their potential role for the repair of massive defects that demands the simultaneous restoration of multiple, missing tissue types. These complex flaps can be sorted into two major classes, and their subtypes on the basis of their means of vascularization are described. (1) Solitary vascularization, the composite flap: "multiple tissue components with a single vascular supply and dependent parts." (2) Combined flaps: (a) Siamese flaps: "multiple flap territories, dependent due to some common physical junction, yet each retaining their independent vascular supply"; (b) conjoint flaps: "multiple independent flaps, each with an independent vascular supply, but linked by a common indigenous source vessel"; and (c) sequential flaps: "multiple independent flaps, each with an independent vascular supply, and artificially linked by a microanastomosis." Many technical modifications that have improved or will improve the reliability of these flaps should not be confused as distinct flap types, but rather acknowledged as variations that can be more conveniently classified for the purposes of improved communication and research by using this basic schema as a guideline.