Anatomical study and colour Doppler assessment of the skin perforators of the anterior tibial artery and possible clinical applications

Three-Dimensional Digitalized Virtual Planning of Free Anterior Tibial Artery Perforator Flap for Repairing Soft Tissue Defects in Extremities

BACKGROUND

Traditional research methods have limited the application of anterior tibial artery perforator flap due to incomplete knowledge of the perforator. This study aimed to investigate the feasibility of three-dimensional digitalized virtual planning of free anterior tibial artery perforator flap for repairing soft tissue defects in extremities.

METHODS

A total of 11 patients with soft tissue defects in extremities were included. The patient underwent computed tomography angiography (CTA) of bilateral lower limbs, and then the three-dimensional models of bones, arteries, and skin were constructed. Septocutaneous perforators with appropriate length and diameter were selected to design anterior tibial artery perforator flaps in software, and the virtual flaps were superimposed onto the patient's donor site in a translucent state. During the operation, the flaps were dissected and anastomosed to the proximal blood vessel of the defects as designed.

RESULTS

Three-dimensional modeling showed clear anatomical relationships between bones, arteries, and skin. The origin, course, location, diameter, and length of the perforator obtained during the operation were consistent with those observed preoperatively. Eleven anterior tibial artery perforator flaps were successfully dissected and transplanted. Postoperative venous crisis occurred in one flap, partial epidermis necrosis occurred in another flap, while the remaining flaps completely survived. One flap was treated with debulking operation. The remaining flaps maintained aesthetic appearance, which did not affect the function of the affected limbs.

CONCLUSIONS

Three-dimensional digitalized technology can provide comprehensive information on anterior tibial artery perforators, thus assisting in planning and dissecting patient-specific flaps for repairing soft tissue defects in extremities.

Arterial Injury Portends Worse Soft Tissue Outcomes and Delayed Coverage in Open Tibial Fractures

OBJECTIVES

To investigate if any injury to the three primary branches of the popliteal artery in open tibia fractures lead to increased soft-tissue complications, particularly in the area of the affected angiosome.

DESIGN

Retrospective cohort comparative study.

SETTING

Two academic level one trauma centers.

PATIENTS/PARTICIPANTS

Sixty-eight adult patients with open tibia fractures with a minimum one-year follow up.

INTERVENTION

N/A.

MAIN OUTCOME MEASUREMENTS

Soft-tissue outcomes as measured by wound healing (delayed healing, dehiscence, or skin breakdown) and fracture related infection (FRI) at time of final follow-up.

RESULTS

Eleven (15.1%) tibia fractures had confirmed arterial injuries via CTA (7), direct intraoperative visualization (3), intraoperative angiogram (3). Ten (91.0%) were treated with ligation and 1 (9.1%) was directly repaired by vascular surgery. Ultimately, 6 (54.5%) achieved radiographic union and 4 (36.4%) required amputation performed at a mean of 2.62 ± 2.04 months, with one patient going on to nonunion diagnosed at 10 months. Patients with arterial injury had significantly higher rates of wound healing complications, FRI, nonunion, amputation rates, return to the OR, and increased time to coverage or closure. After multivariate regression, arterial injury was associated with higher odds of wound complications, FRI, and nonunion. Ten (90.9%) patients with arterial injury had open wounds in the region of the compromised angiosome, with 7 (70%) experiencing wound complications, 6 (60%) FRIs, and 3 (30%) undergoing amputation.

CONCLUSIONS

Arterial injuries in open tibia fractures with or without repair, have significantly higher rates of wound healing complications, FRI, delayed time to final closure, and need for amputation. Arterial injuries appear to effect wound healing in the affected angiosome.

LEVEL OF EVIDENCE

Prognostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Perforator propeller flaps for lower extremity soft-tissue defect reconstruction: Shortening the learning curve

Background

The perforator propeller flap is an advantageous option for soft tissue reconstruction in the lower limb as it ensures the preservation of the main artery and muscle, eliminates the need for microsurgical reconstruction as well as provides "like with like" resurfacing of the defects. Despite this, it remains a technically demanding reconstructive option for residents and surgeons with little experience in perforator dissection. We aimed to evaluate the clinical outcomes of our patients whose soft tissue defects were addressed with propeller flaps.

Methods

A retrospective study of all propeller flap based reconstruction done on patients with soft tissue defects involving the distal third of the leg was undertaken from August 2018 to December 2020.

Results

28 patients were treated with propeller flaps for various lower extremity defects. The median defect size was 12 cm². The posterior tibial artery (PTA) was used in eleven cases (39.3%) and the peroneal artery (PA) in seventeen of the cases (60.7%). The complication rate was 28.6% (n = 8). The complete flap necrosis rate was 10.7% (n = 3) and partial flap necrosis rate was 7.1% (n = 2), The rate of venous congestion was 7.1% (n = 2) and wound dehiscence occurred in 3.5% (n = 1). There was a significant negative correlation between the number of cases performed by a resident and the operative time.

Conclusion

Although propeller flaps are a reliable option to address lower extremity defects, they have a long learning curve and require a good amount of experience and perforator dissection skills to reduce the probability of flap failure. We are of the opinion that residents should be adequately trained in this procedure to ensure optimal outcome delivery.

Modified Anterior Tibial Artery Perforator-Pedicled Propeller Flap for Soft-Tissue Coverage of the Ankle and Heel

BACKGROUND

The ankle and heel are challenging regions to reconstruct functionally. Here, we explored the feasibility and clinical outcomes of a modified anterior tibial artery perforator-pedicled propeller flap for the repair of soft-tissue defects of the ankle and heel.

PATIENTS AND METHODS

Between January 2013 and December 2015, 12 patients with soft-tissue defects of the ankle and/or heel underwent reconstructive surgery that included our flap technique. The flaps measured 20 × 8 cm to 7 × 4 cm. A hand-held Doppler was used to identify a proper constant perforator in the distal ankle. In each case, the base of the flap was well preserved. The flap was transposed (180° rotation) to reach and cover the defect.

RESULTS

The average follow-up time was 13 months (10-28 months). We observed good texture matches and contour in all of the flaps. All patients could walk and wear normal footwear. All but one flap survived completely without complications. Partial loss was observed in one patient, and the necrotic region was healed with secondary intention.

CONCLUSION

Our modified anterior tibial artery free-style perforator-pedicled propeller flap provides a novel option for functional ankle and heel reconstruction.

LEVEL OF EVIDENCE

Level IV.

The suprafascial course of lower leg perforators: An anatomical study

BACKGROUND

Perforator mapping has been well described in the literature. Once the suprafascial plane is reached, the course of perforators is considered constant. However, the surgeon must be aware of whether an anastomosis exists between perforators superficially to the fascia, in order to choose the best vessel upon which to base the reconstruction. Our retrospective in vivo anatomical study of lower leg perforator flaps presents the first description of variations in the suprafascial path of perforators, which may influence preoperative flap design.

METHODS

An anatomical study of lower limb perforators was performed on 46 nonconsecutive patients who were referred to our department from June 2012 to October 2018. Reconstruction with perforator-based propeller flaps was planned for each of the patients. In total, 72 perforators were preoperatively identified and surgically isolated. The suprafascial course of each perforator was reported.

RESULTS

During suprafascial surgical exploration, branching patterns were observed in four perforators. These perforators had been classified as single vessels in the preoperative ultrasonographic analysis. However, after surgical dissection, distal converging branches were noted in two of them.

CONCLUSIONS

Our study is the first description in the literature of suprafascial converging perforators, which might constitute an obstacle to planned reconstruction procedures. Despite the accuracy of preoperative evaluations, anatomical variations were present. Knowledge of suprafascial perforator variations may help surgeons to choose the correct perforator upon which to base a planned flap.

Perforator Propeller Flaps for the Coverage of Middle and Distal Leg Soft-tissue Defects

Background:

Local propeller flaps preserve the main vascular arteries of the lower extremity and muscle function, avoiding the need for a microsurgical anastomosis and the benefit of providing a “like with like” coverage. Our goal in this study was to demonstrate the versatility, safety, and complications of the local propeller flaps for lower extremity reconstruction.

Methods:

We present a series of 28 patients in whom we used local propeller flaps to restore small-to-medium soft-tissue defects of the lower limb in different hospitals of Managua, Nicaragua.

Results:

Flap average dimensions were of 48 cm². Flap rotation was performed in 180 degrees in 85% of the cases. The propeller flaps were based on a single perforator, from the posterior tibial artery in 50%, anterior tibial artery in 39.3%, and peroneal artery in 10.7% of the cases. Complications occurred in 14% of the propeller flaps performed, with 3 partial necrosis of less than 15% of the flap transposed. Complications of the patients occurred in both sex groups; however, for the female group, there was a 75% of complications with a tendency toward statistical significance of P = 0.038. Donor site of the flap was closed primarily in 85.7% (24) of the cases.

Conclusions:

In our opinion, the availability and safety of local propeller flaps, justifies its use in cases where microsurgical techniques are not an option for the reconstruction of the middle and distal extremity, in small-to-medium defects of soft-tissue coverage of the lower limb.

Color Doppler Ultrasonography-Targeted Perforator Mapping and Angiosome-Based Flap Reconstruction

Knowledge about perforators and angiosomes has inspired new and innovative flap designs for reconstruction of defects throughout the body. The purpose of this article is to share our experience using color Doppler ultrasonography (CDU)-targeted perforator mapping and angiosome-based flap reconstruction throughout the body. The CDU was used to identify the largest and best-located perforator adjacent to the defect to target the reconstruction. The cutaneous or fasciocutaneous flaps were raised, mobilized, and designed according to the reconstructive needs as rotation, advancement, or turnover flaps. We performed 148 reconstructions in 130 patients. Eleven facial reconstructions, 118 reconstructions in the body, 7 in the upper limbs, and 12 in the lower limbs. The propeller flap was used in 135 of 148 (91%) cases followed by the turnover design in 10 (7%) and the V to Y flap in 3 (2%) cases. The flaps were raised on 1 perforator in 98 (67%), 2 perforators in 48 (33%), and 3 perforators in 2 (1%) flaps. The reconstructive goal was achieved in 143 of 148 reconstructions (97%). In 5 cases, surgical revision was needed. No flaps were totally lost indicating a patent pedicle in all cases. We had 10 (7%) cases of major complications and 22 (15%) minor complications. The CDU-targeted perforator mapping and angiosome-based flap reconstruction are simple to perform, and we recommended its use for freestyle perforator flap reconstruction. All perforators selected by CDU was identified during surgery and used for reconstruction. The safe boundaries of angiosomes remain to be established.

Color Doppler Sonographic and Cadaveric Study of the Arterial Vascularity of the Lateral Upper Arm Flap

OBJECTIVES

To determine the importance of adequate preoperative assessment with color Doppler sonography to assist in the successful transfer of lateral upper arm flaps by studying the lateral upper arm flap with color Doppler sonography and analyzing the anatomic features of the radial collateral artery.

METHODS

A clinical case-control study was performed. The radial collateral artery was studied with color Doppler sonography in 15 healthy volunteers. The origins, courses, variations, and locations of the perforators of the radial collateral artery were recorded. The results and data from the color Doppler sonographic investigation were compared with an anatomic study that was performed on 22 adult cadaveric upper limb specimens.

RESULTS

The volunteer group (14 of 15 volunteers) and the cadaveric group (19 of 22 upper arm specimens) clearly showed that the branch pattern of the arterial supply was as follows: brachial artery → deep brachial artery → radial collateral artery → posterior radial collateral artery → myocutaneous perforator. Variations in the origin of the radial collateral artery were identified in 1 volunteer bilaterally and in 3 upper arm specimens. The diameters of the artery and vein measured at the distal insertion of the deltoid and the origin of the deep brachial artery were not significantly different between the volunteer and cadaver groups (P > .05). Due to the difference in measuring methods, the length of the vascular pedicles was significantly different between the groups (P < .05).

CONCLUSIONS

Color Doppler sonography can facilitate the preoperative assessment of the origin, course, variations, and locations of the radial collateral artery and therefore may increase the success rate of lateral upper arm flap transfer.

Redefining the Vascular Classifications of the Lateral Supramalleolar Flap

BACKGROUND

The blood supply of the lateral supramalleolar flap (LSMF) generally comes from the perforating branch of the peroneal artery. However, the cutaneous branch may also receive blood from the anterior tibial artery. The main objective of the present study was to clarify the vascular anatomy of the LSMF.

METHODS

Anatomical dissections were performed on 28 perfused fresh cadaver legs. The cutaneous branches of LSMF were identified, and the anatomic relationship between the cutaneous branches and the peroneal and anterior tibial arteries was analyzed.

RESULTS

The vascular supply for LSMF was divided into 2 main types. A collateral inferolateral branch from the anterior tibial artery anastomosed with the perforating branch of the peroneal artery around the inferior tibiofibular angle, and the main cutaneous branch of the flap arose from this arterial anastomosis in 20 of 28 limbs (71.4%). The collateral inferolateral branch was absent or very small in the other 8 of 28 dissections (28.6%), and the cutaneous branches solely arose from the perforating branch of the peroneal artery. The anastomosis of the descending branch of the peroneal artery and anterior lateral malleolar artery was always (100%) found around the tibiotalar joint.

CONCLUSIONS

In addition to the perforating branch of the peroneal artery, the LSMF may also receive blood from the anterior tibial artery through the collateral inferolateral branch. New modified proximally based flaps could be designed, and caution is warranted for these variations when a distally based flap is performed.

Preplanning vascularized lymph node transfer with duplex ultrasonography: an evaluation of 3 donor sites

Background:

As experience with vascularized lymph node (VLN) transfer has grown, new VLN sources have become apparent. Descriptive studies have elucidated variable lymph node presence in these donor basins. Yet, no study has evaluated preoperative imaging evaluation between donor sites in patients undergoing VLN transfer. This study was to compare the findings on duplex ultrasonography of the submental, groin, and supraclavicular lymph node basins in patients undergoing VLN transfer.

Methods:

A review of a prospective database was performed for patients who had undergone preoperative planning for VLN transfer with duplex ultrasonography to provide objective donor-site characteristics. Multiple regression analysis was used to identify factors that correlated with specific flap characteristics. A P value less than 0.05 was considered statistically significant.

Results:

Sixty-eight patients (28 upper extremities and 40 lower extremities) were identified as undergoing preoperative duplex ultrasonography for VLN transfer. Little variation was seen when evaluating donor sites for laterality in patients. Groin and submental VLN sites had 3.1 and 3.3 lymph nodes, respectively, compared with 0.9 lymph nodes in the supraclavicular donor site (p < 0.01). Increasing age had an inverse relationship with estimated flap volume, whereas higher body mass index correlated with increasing flap thickness.

Conclusions:

Preoperative imaging with duplex ultrasonography before VLN transfer may allow for accurate identification of specific VLN donor-site characteristics. When considering lymph node–specific characteristics, higher quantity of lymph nodes were found on the groin and submental flap axis compared with the transverse cervical artery axis.

Are there risk factors for complications of perforator-based propeller flaps for lower-extremity reconstruction?

BACKGROUND

Conventional pedicled flaps for soft tissue reconstruction of lower extremities have shortcomings, including donor-site morbidity, restricted arc of rotation, and poor cosmetic results. Propeller flaps offer several potential advantages, including no need for microvascular anastomosis and low impact on donor sites, but their drawbacks have not been fully characterized.

QUESTIONS/PURPOSES

We assessed (1) frequency and types of complications after perforator-based propeller flap reconstruction in the lower extremity and (2) association of complications with arc of rotation, flap dimensions, and other potential risk factors.

METHODS

From 2007 to 2012, 74 patients (44 males, 30 females), 14 to 87 years old, underwent soft tissue reconstruction of the lower extremities with propeller flaps. General indications for this flap were wounds and small- and medium-sized defects located in distal areas of the lower extremity, not suitable for coverage with myocutaneous or muscle pedicled flaps. This group represented 26% (74 of 283) of patients treated with vascularized coverage procedures for soft tissue defects in the lower limb during the study period. Minimum followup was 1 year (mean, 3 years; range, 1-7 years); eight patients (11%) were lost to followup before 1 year. Complications and potential risk factors, including arc of rotation, flap dimensions, age, sex, defect etiology, smoking, diabetes, and peripheral vascular disease, were recorded based on chart review.

RESULTS

Twenty-eight of 66 flaps (42%) had complications. Venous congestion (11 of 66, 17%) and superficial necrosis (seven of 66, 11%) occurred most frequently. Eighteen of the 28 complications (64%) healed with no further treatment; eight patients (29%) underwent skin grafting, and one patient each experienced total flap failure (2%) and partial flap failure (2%). In those patients, a free anterolateral thigh flap was used as the salvage procedure. No correlations were found between complications and any potential risk factor.

CONCLUSIONS

We were not able to identify any specific risk factors related to complications, and future multicenter studies will be necessary to determine which patients or wounds are at risk of complications. Propeller flaps had a low failure rate and risk of secondary surgery. These flaps are particularly useful for covering small- and medium-sized defects in the distal leg and Achilles tendon region and are a reliable and effective alternative to free flaps.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.

Can we consider standard microsurgical anastomosis on the posterior tibial perforator network? An anatomical study

PURPOSE

The main vessels in an injured leg can be spared with perforator-to-perforator anastomosis. However, supermicrosurgery is not a routine procedure for all plastic surgeons. Our objective was to establish if the diameter of the perforators of the leg could allow anastomosis with standard microsurgical procedures.

METHODS

Twenty lower legs harvested from ten fresh cadavers were dissected. Arterial and venous vessels were injected with colored latex. The limbs were then dissected in a suprafascial plane. All the perforating arteries of a diameter >0.8 mm were located and their external diameter, the number and external diameter of the venae comitantes were reported.

RESULTS

We found at least three tibial posterior artery perforators with diameters >0.8 mm per leg with a mean external diameter of 1.1 mm and one vena comitans in almost all cases (96 %). The vena comitans was usually bigger than the perforating artery with a mean diameter of 1.6 mm. After statistical analysis, we were able to locate two main perforator clusters: at the junctions of the upper two-thirds of the leg and of the lower two-thirds of the leg.

CONCLUSION

The low-morbidity concept of perforator-to-perforator anastomosis can apply to posterior tibial artery perforators without using supermicrosurgical techniques. This is of high interest for open leg fractures where main vessels could be injured. We hope that the results of our study will incite surgeons to consider sparing of main vessels for coverage of open leg fractures whether surgical teams master supermicrosurgery or not.