Selection of recipient vessels for free flaps to the distal leg and foot following trauma

Lower Extremity Reconstruction with Anterolateral Thigh Free-Flap Anastomoses: A Computational Fluid Dynamic Analysis

BACKGROUND

 The anterolateral thigh free flap is an option for repairing soft tissue defects of the distal lower extremity. This flap uses the descending branch of the lateral circumflex femoral (LCF) artery as the flap vessel. The recipient vessel in these flaps is often the anterior tibial (AT), posterior tibial (PT), or peroneal (P) arteries. Computational fluid dynamic (CFD) evaluation of anastomoses between these vessels can optimize outcomes.

METHODS

 Thirty-eight CFD models were created to model end-to-side (ETS) and end-to-end (ETE) anastomoses for lower extremity reconstruction. Seven out of thirty-eight models represented ETS anastomoses between the LCF and AT arteries with varying anastomotic angles. Nine out of thirty-eight models represented 45-degree ETS anastomoses between varying diameters of the LCF and AT, PT, and P arteries. Nine out of thirty-eight models represented stenosis on the flap vessel and recipient vessel, pre- and post-bifurcation. Nine out of thirty-eight models represented ETE anastomoses, rather than ETS, with varying vessel diameters. Four out of thirty-eight models represented ETE anastomoses with varying regions and levels of stenosis.

RESULTS

 Stasis of blood flow in ETS models increased as anastomotic angle increased in a logarithmic relationship (R 2 = 0.918). Flow was optimized overall as flap and recipient vessel diameters approached one another. In ETS models, flap vessel and postbifurcation recipient vessel stenosis were found to substantially increase stasis.

CONCLUSION

 Selection of flap and recipient vessels with similar diameters can optimize outcomes in microvascular anastomoses. In the context of lower extremity reconstruction with the ALT flap, the PT artery can be recommended as a first-line recipient vessel due to its similar vessel caliber to the LCF and relative ease of surgical access compared with the P artery. Avoidance of areas of stenosis is recommended to ensure laminar flow and reduce the operative difficulty associated with performing anastomoses on nonpliable arteries. Striving for increased acuity of anastomotic angles is recommended to optimize the flow in ETS microvascular anastomoses.

An algorithmic approach to soft-tissue reconstruction around the knee using anterolateral thigh perforator flap in patients with post-traumatic knee osteomyelitis

Background

Free tissue transfer to the knee region in patients with chronic post-traumatic knee osteomyelitis (CTKOM) poses a great challenge to surgeons because the remaining soft tissues adjacent to defects, including vascular structures, are usually damaged by chronic inflammation and multiple debridements. Thus, we developed an algorithm to help select the optimal recipient vessels and appropriate anterolateral thigh perforator (ALTP) flap type. In addition, we performed surgery using this algorithm and achieved successful reconstructions. This study aims to review our experiences in algorithmic reconstruction and assess its efficacy.

Methods

According to the defect size and location, our algorithm suggested the use of various-shaped ALTP flaps with centrally located perforators (Cen-ALTP flap) or eccentrically located perforators (Ecc-ALTP flap). Besides, through the algorithm, one recipient vessel was selected among three candidates, including descending branch of the lateral circumflex femoral artery (DB-LCFA), anterior tibial artery (ATA), and posterior tibial artery (PTA). Based on this algorithmic decision, we performed individualized soft tissue reconstructions of the knee in 21 patients with CTKOM, between March 2013 and June 2021. The medical records of the patients were retrospectively reviewed.

Results

The Cen-ALTP flap (n = 15) and ATA (n = 9) were the most commonly used for reconstruction. The Cen-ALTP flap anastomosed to the ATA was most commonly selected (n = 7) using the algorithm, followed by the Cen-ALTP flap anastomosed to the DB-LCFA (n = 5), and the Cen-ALTP flap anastomosed to the PTA (n = 3). All transferred ALTP flaps survived the follow-up period. Postoperative venous congestion in two patients and hematoma in one patient were resolved by immediate treatment. The postoperative course was uneventful.

Conclusion

During free ALTP flap transfer to CTKOM-related knee defects, we could select the optimal recipient vessel and appropriate flap type using our algorithm and obtain excellent reconstructive outcomes. Therefore, we believe that our algorithm could provide helpful guidance to reconstructive surgeons on free ALTP flap transfer to reconstruct CTKOM-related soft tissue defects.

Microvascular free tissue transfer for reconstruction of complex lower extremity trauma: Predictors of complications and flap failure

BACKGROUND

Despite advanced wound care techniques, open fractures in the setting of lower extremity trauma remain a challenging pathology, particularly when free tissue transfer is required for coverage. We aimed to evaluate factors associated with flap failure in this setting using a large, heterogeneous patient population.

METHODS

Retrospective review of patients who underwent traumatic lower extremity free flap reconstruction (2002-2019). Demographics wound/vessel injury characteristics, pre and perioperative factors, and flap outcomes were analyzed.

RESULTS

One hundred eighty-eight free flaps met inclusion criteria, with 23 partial (12.2%) and 13 total (6.9%) flap failures. Angiography was performed in 87 patients, with arterial injury suffered in 43.1% of those evaluated. Time to flap coverage varied within 3 days (4.5%), 10 days (17.3%), or 30 days of injury (42.7%). In all, 41 (21.8%) subjects suffered from major flap complications, including failure and takebacks. Multivariate regression demonstrated the presence of posterior tibial (PT) artery injury predictive of both flap-failure (Odds ratio [OR] = 11.4, p < .015) and major flap complications (OR = 12.1, p < .012). Immunocompromised status was also predictive of flap failure (OR = 12.6, p < .004) and major complications (OR = 11.6, p < .007), while achieving flap coverage within 30 days was protective against flap complications (OR = 0.413, p < .049). Defect size, infection, and injury location were not associated with failure.

CONCLUSIONS

When examining a large, heterogeneous patient cohort, free flap outcomes in the setting of lower extremity open fractures can be influenced by multiple factors. This presence of PT artery injury, flap coverage beyond 30 days of injury, and immunocompromised status appear predictive of flap complications in this context.

Microsurgical anastomosis using anterior versus posterior tibial artery in lower limb free tissue transfer

BACKGROUND

Soft tissue lower limb reconstruction often requires free tissue transfer. We investigated whether the target vessels used for micro-vascular anastomosis in the lower limb influences microsurgical outcomes.

METHODS

Data from Plastic Surgery Departments of a major tertiary hospital in the United Kingdom (Leeds General Infirmary, LGI) and Australia (Princess Alexandra Hospital, PAH) were retrospectively analysed. Patients who underwent lower limb free flap reconstruction using the posterior (PTA) or anterior tibial artery (ATA) were included. Patient demographics, free flap and microvascular anastomosis details were analysed. Primary outcome was flap failure. Secondary outcome was return to theatre.

RESULTS

Two hundred and thirty-four free flaps were included (PAH 115; LGI 119). 60% were muscle flaps. Eighty-one percent of patients were male, with trauma the cause in 82%. PTA was used for microsurgical anastomosis in 70% of cases. Venae comitantes were preferred (96%) for venous anastomosis. PTA group showed a higher proportion of patients with trauma as the mechanism of injury. ATA group was more likely to have an end-to-end arterial anastomosis configuration. Total flap loss was 3.8%. There was no clinically significant difference in flap failure or return to theatre using ATA versus PTA.

CONCLUSIONS

Incidence of lower limb free flap failure is low (<5%) and not influenced by use of ATA versus PTA for microsurgical anastomosis. The choice of target vessels for microsurgical reconstruction of the lower limb should be predicated upon factors other than aversion to one or another vessel. If all other microsurgical considerations are equal, the surgeon can exercise personal preference.

Avoiding iatrogenic vascular injury in tibial external fixation with half pins. An in-vivo study based on CT angiography

BACKGROUND

External fixation is an important tool in the management of variety of tibial fractures. Appropriate half pin insertion is important, to provide stable fixation without compromising the surgical field for definitive surgical procedures, and avoiding further damage to the important structures of the traumatized limb. There is paucity of literature about the optimal trajectories and safe corridors for half pins insertion based on in vivo studies. The available studies are based on anatomic atlases, cadaveric studies or half pin related complications.The aim of the current study is to present the findings of CT angiograms, in patients with external fixation of tibia, to enhance our understanding of optimal trajectories in safe corridors for half pins insertion.

MATERIAL AND METHODS

We performed a retrospective study of patients with external fixators on the tibia, who had undergone CT angiogram as part of pre-operative planning for orthoplastic reconstructive procedures. The relationship between the tips of the fixator half pins and named vessels of the leg were analyzed, pins within 5 mm of a named vessel were considered to be a risk of causing iatrogenic injury.

RESULTS

A total 51 patients, with in situ temporizing external fixators, with 134 half pins in different segments of the tibia were analyzed. More than 5 mm of penetration beyond the far cortex was noted in 47%, while in another 16% of pins penetration was more than 10 mm beyond the cortex. A tip to vessel distance (TVD) of 5 mm or less was noted in 28/134 (21%) of the pins, which highlights potential risk to the neurovascular bundles of the leg.

CONCLUSION

Risk of iatrogenic injury to neurovascular structures from half pin insertion can be reduced by meticulous use of fluoroscopy, by avoiding penetration beyond the far cortex, and avoiding exiting with half pins on the lateral surface in the distal 1/3rd of segment II of tibia. Moreover observing optimal trajectories and safe corridors for pin insertion, and selection of appropriate type of half pin can mitigate the risk to these structures.

Computed tomography angiography and microsurgical flaps for traumatic wounds: What is the added value?

BACKGROUND

Microsurgical flaps are widely used to treat complex traumatic wounds of upper and lower limbs. Few studies have evaluated whether the vascular changes in preoperative computed tomography angiography (CTA) influence the selection of recipient vessel and type of anastomosis and the microsurgical flaps outcomes including complications.

OBJECTIVE

The aim of this study was to evaluate if preoperative CTA reduces the occurrence of major complications (revision of the anastomosis, partial or total flap failure, and amputation) of the flaps in upper and lower limb trauma, and to describe and analyze the vascular lesions of the group with CTA and its relationship with complications.

METHODS

A retrospective cohort study was undertaken with all 121 consecutive patients submitted to microsurgical flaps for traumatic lower and upper limb, from 2014 to 2020. Patients were divided into two groups: patients with preoperative CTA (CTA+) and patients not submitted to CTA (CTA-). The presence of postoperative complications was assessed and, within CTA+, we also analyzed the number of patent arteries on CTA and described the arterial lesions.

RESULTS

Of the 121 flaps evaluated (84 in the lower limb and 37 in the upper limb), 64 patients underwent preoperative CTA. In the CTA+ group, 56% of patients with free flaps for lower limb had complete occlusion of one artery. CTA+ patients had a higher rate of complications (p = 0.031), which may represent a selection bias as the most complex limb injuries and may have CTA indicated more frequently. The highest rate of complications was observed in chronic cases (p = 0.034). There was no statistically significant difference in complications in patients with preoperative vascular injury or the number of patent arteries.

CONCLUSIONS

CTA should not be performed routinely, however, CTA may help in surgical planning, especially in complex cases of high-energy and chronic cases, since it provides information on the best recipient artery and the adequate level to perform the microanastomosis, outside the lesion area.

Peroneal Artery-based Propeller Flap to Cover the Medial Distal Tibia in the Absence of the Posterior Tibial Artery

A healthy 28-year-old woman restrained driver presented to the trauma unit post-MVC with significant vehicular intrusion. Examination demonstrated a 15-cm transverse wound over the medial malleolus and anterior ankle with exposed muscle, tendon, and bone without gross contamination. Her physical examination was otherwise unremarkable. Distal to the wound, there was no Doppler signal in either dorsalis pedis or posterior tibial arteries and the foot appeared cold with delayed cap refill. She was taken to the operating room urgently for debridement and irrigation, open reduction internal fixation of both distal tibia and fibular fractures, and supplemental external fixation application. The foot regained a normal color and capillary refill upon reduction, and biphasic Doppler signals returned.

Medial approach to the peroneal vessels as recipients for free flap reconstruction of the leg

The anatomic variation in the branching pattern of the popliteal vessel has been well-established. Little has been written in the literature regarding recipient vessel selection for microvascular reconstruction in the lower extremity as it pertains to aberrant vascular anatomy. We present the case of a 57-year-old male patient who sustained a closed right lower extremity pilon fracture in a motor vehicle accident. The patient was initially treated with external fixation, which was followed by definitive open reduction and internal fixation 3 weeks later. Over the next 2 weeks, the patient developed skin ischemia of the anterior ankle. A free-tissue transfer was planned. A digital subtraction angiogram revealed absence of the posterior tibial (PT) vessels and an aberrant course of the peroneal (PR) artery. In the operating room, the medial distal leg was explored for the PT vessels, which were severely hypoplastic. Given the close proximity of the PR vessels, the dissection was extended proximally to assess these vessels for microvascular anastomosis. They were found to be suitable. A parascapular flap was harvested and transferred to the right leg wound without any significant stretch on the vessels for soft tissue coverage. The flap demonstrated excellent inflow and outflow, and the leg and foot remained well perfused. The patient's postoperative course was uncomplicated. The technique of exposing the peroneal vessels for microvascular anastomosis via a medial approach is described. This technique is an excellent option to have available when aberrant anatomy precludes the use more commonly utilized vessels.

Management of Post-Traumatic Osteomyelitis in the Lower Limb: Current State of the Art

Osteomyelitis (OM) of the lower limb represents a large unmet global healthcare burden. It often arises from a contiguous focus of infection and is a recognized complication of open fractures or their surgical treatment, arthroplasty, and diabetic foot ulcers. Historically, this debilitating condition is associated with high rates of recurrence and secondary amputation. However, excellent long-term outcomes are now achieved by adopting a multidisciplinary approach with meticulous surgical debridement, skeletal and soft tissue reconstruction, and tailored antimicrobial treatment. This review focuses on the modern evidence-based management of post-traumatic OM in the lower limb from a reconstructive plastic surgery perspective, highlighting the latest developments and areas of controversy.

How common are vascular injuries in open tibial fractures? A prospective longitudinal cohort study

BACKGROUND

Tibial fractures have an incidence of 15% of all adult fractures. They have been shown to have the highest incidence of non-union in long bone fractures and the highest incidence of vascular injury. Evidence from the literature suggests that a good vascular supply is important to ensure bone union. The aim of our study was to prospectively assess the incidence of vascular injuries in open tibial fractures and determine whether they were associated with an increased risk of non-union.

METHODS

We performed a prospective study to investigate the incidence of arterial injuries with computed tomography angiography (CTA) in patients with Gustilo-Anderson grade I-III open tibial fractures between 2013 and 2015. CTA was performed with the trauma series at acute admission and reported by two independent musculoskeletal radiologists. Patients were followed up with clinical and radiographic assessment for 1 year.

RESULTS

We recruited 77 patients into the study, and 56 patients (47 males, 9 females) were available for the final analysis, between 16 and 90 years of age. At the initial assessment, 29% had signs of arterial injury with active extravasation in 5%. The most common site of injury was in the diaphysis (87.5%), and the commonest mechanism was a road traffic accident. We found no significant relation between occult vascular injury and non-union (p > 0.05).

CONCLUSION

The incidence of vascular injury in open tibial fractures is 29%, and CTA is therefore a useful test in identifying vascular injuries that may require vascular intervention.

Validity of the use of a subfascial vessel as the recipient vessel in a second free flap transfer: A retrospective clinical review

Performing a greater number of free flap procedures inevitably results in an increase in the number of cases that experience free flap failure. In cases that require a second free flap after the failure of the first, recipient vessel selection becomes difficult. Furthermore, recipient vessel selection can be complicated if the vessel is deep in the recipient site, or if there is an increased risk of vessel damage during the dissection. Thus, we present our experience where a subfascial vessel beneath the deep fascia was used as a recipient vessel for a second free flap in lower extremity reconstruction due to total or partial first flap failure.Between January 2010 and April 2015, 5 patients underwent second free flap reconstruction using a subfascial vessel as the recipient vessel. The flaps were anastomosed in a perforator-to-perforator manner, using the supermicrosurgery technique. We measured the sizes of the flaps, which varied from 5 × 3 to 15 × 8 cm, and the recipient subfascial vessel diameters.The mean time for the dissection of the recipient perforator was 45 minutes. All the flaps exhibited full survival, although a partial loss of the skin graft at the flap donor site was observed in 1 patient; this defect healed with conservative management.We recommend using a subfascial vessel as the recipient vessel for both first and second free flaps, especially if access to the major vessel is risky or challenging.

Microsurgical Reconstruction of Traumatic Lower Extremity Defects in the Pediatric Population

BACKGROUND

Few reports focus exclusively on microsurgical reconstruction of traumatic lower extremity defects in children. Hence, the authors felt it prudent to contribute to this area of clinical research. The authors hypothesized that reconstructive success would be comparable to success rates reported in adults, and that young age or concerns regarding vessel size or behavior do not negatively impact surgical outcome.

METHODS

A retrospective review of microsurgical lower extremity reconstruction cases at two academic medical centers was performed. All pediatric patients who underwent microsurgical reconstruction of traumatic lower extremity defects between 1997 and 2012 were included for analysis.

RESULTS

Forty flaps transferred in 40 patients with a mean age of 11.4 years (range, 1 to 17 years) were included for analysis. Muscle flaps were predominantly used [n = 23 (57.5 percent)]; however, there was a recent increase in use of fasciocutaneous flaps [n = 16 (40 percent)]. Postoperative complications were seen in 25 percent of patients, with a total flap loss rate of 5 percent. No donor-site complications were observed. The mean postoperative length of hospital stay was 12.9 days (range, 4 to 41 days), with patients returning to full weight-bearing after a mean of 2.6 months (range, 1 to 8 months).

CONCLUSIONS

Microsurgical reconstruction of traumatic lower extremity defects in the pediatric population is safe. Concerns related to patient age, vessel size, or vessel behavior (i.e., vasospasm) should not detract from offering free flap reconstruction, as they do not negatively impact outcomes.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Extending the limits of the anterior tibial artery as the recipient vessel for around the knee and proximal lower extremity defect reconstruction using the free anterolateral thigh and gracilis flap

PURPOSE

The aim is to describe a technique with orthograde dissection of the anterior tibial artery (ATA) used as the recipient vessel for the end-to-end (ETE) anastomosis in defect reconstruction around the knee and for proximal/middle third leg defects with free anterolateral thigh (ALT) and gracilis flaps.

PATIENTS AND METHODS

Between March 2009 and May 2014, 22 patients undergoing lower extremity reconstruction were evaluated. Of those, 4 patients were included. The locations of injury were 3 defects around the knee and 1 defect at the proximal and middle third of the lower leg (mean defect size 18 x 8.5 cm and a range of 17-20 x 5-10 cm). There were 2 cases after trauma and 2 cases with infection. Two free gracilis and 2 free ALT flaps were performed of equal size to the defects. The mean flap pedicle length was 11 cm (range of 7-16 cm) and the mean length of the mobilized recipient vessels was 10.5 cm (range of 6-14 cm).

RESULTS

One flap loss (ALT) occurred, requiring a salvage procedure with a latissimus dorsi flap, whereas wound dehiscence at the donor site and a hematoma below the ALT flap was observed in 2 cases, requiring small revision. After a mean follow-up of 52 months (range of 38-87 months), there was stable soft tissue coverage in all patients.

CONCLUSION

By orthograde dissection of the ATA, an adequate vessel length and size may be achieved, improving arc of rotation to successfully cover more distant defects.

The lateral calcaneal artery as an alternative recipient vessel option for heel and lateral foot reconstruction

BACKGROUND

Clinical outcomes of consecutive use of the lateral calcaneal artery (LCA) as a recipient vessel for microsurgical reconstruction have not been reported. This study aimed to evaluate the feasibility and safety of the LCA as a recipient vessel for microsurgical foot reconstruction based on anatomical study of CT angiography and clinical results of using this vessel as the recipient.

METHODS

Anatomic study was performed using CT angiography of 61 lower extremities (31 patients). The emerging point, course, and diameter of the LCA were evaluated using 3-D reconstructed images. The LCA was used as the recipient artery in 17 consecutive patients with a mean age of 59 years (range: 23-77 years). Thoracodorsal artery perforator flap was used in most cases (16 of 17), and clinical outcomes were evaluated.

RESULTS

The LCA emerged 31.1 ± 9.8 mm proximal and 14.7 ± 5.0 mm posterior to the tip of the fibula and traversed 13.9 ± 2.7 mm posterior to the posterior margin of the lateral malleolus. The accompanying vein was used for venous outflow in five patients and the small saphenous vein was used in the remaining cases. Emergent re-operation was performed in one case due to venous thrombosis, and salvage was successful. All flaps except for one with partial flap necrosis completely survived. During a mean follow-up of 13 months, all but one of the patients were able to wear shoes and walk.

CONCLUSIONS

The LCA may be safely used as a recipient vessel for microsurgical heel and lateral foot reconstruction.

LEVEL OF EVIDENCE

IV.

Preoperative Angiographic Criteria for Predicting Free-Flap Transfer Outcomes in Patients With Lower-Extremity Peripheral Arterial Disease

Patients scheduled for microsurgical reconstruction of the lower leg often receive preoperative assessment of recipient vessels using angiography. However, no clear standard is available for evaluating angiographic results to predict free-flap survival outcomes. We developed angiographic criteria for predicting surgical outcome in patients with lower-extremity peripheral arterial disease based on abnormality of the anterior tibial and posterior tibial arteries. We applied the criteria to a small number of patients scheduled for microsurgical reconstruction of the lower leg. Angiographies with arterial abnormalities were classified into 3 groups: favorable free-flap survival, compromised free-flap survival, and postsurgical pedal ischemia. The study enrolled 50 patients between 2005 and 2013. In 42% of patients, arterial abnormalities were observed by angiography. Age >65 years was the strongest risk factor for development of lower-leg arterial abnormality ( P < .001). The anterior tibial and peroneal arteries were significantly more stenotic than other vessels. In the favorable free-flap survival and compromised free-flap survival groups, free-flap transfers were attempted in 7 patients but intraoperatively abandoned in 2 patients, with postoperative failure in 1 patient. In the postsurgical pedal ischemia group, free-flap transfers were attempted in 10 patients but intraoperatively abandoned in 6 patients, with postoperative failure in 3.

Free flap transfer to preserve main arterial flow in early reconstruction of open fracture in the lower extremity

The selection of recipient vessels is crucial when reconstructing traumatized lower extremities using a free flap. When the dorsalis pedis artery and/or posterior tibial artery cannot be palpated, we utilize computed tomography angiography to verify the site of vascular injury prior to performing free flap transfer. For vascular anastomosis, we fundamentally perform end-to-side anastomosis or flow-through anastomosis to preserve the main arterial flow. In addition, in open fracture of the lower extremity, we utilize the anterolateral thigh flap for moderate soft tissue defects and the latissimus dorsi musculocutaneous flap for extensive soft tissue defects. The free flaps used in these two techniques are long and include a large-caliber pedicle, and reconstruction can be performed with either the anterior or posterior tibial artery. The preparation of recipient vessels is easier during the acute phase early after injury, when there is no influence of scarring. A free flap allows flow-through anastomosis and is thus optimal for open fracture of the lower extremity that requires simultaneous reconstruction of main vessel injury and soft tissue defect from the middle to distal thirds of the lower extremity.

Recipient vessels in the free flap reconstruction around the knee

Microsurgical free tissue transfer is playing a critical role in reconstruction of the soft tissue around the knee to salvage the limb, especially when the defects exist with a wide zone of injury or with a poor soft tissue condition, where local flaps are unavailable. For a successful free flap transfer, proper selection of a recipient vessel is essential and challenging. The survival and other outcomes of the transferred flaps were closely related to which recipient vessel was used and the location of anastomosis. In this article, we review most of the clinical reports about using free flaps to reconstruct the soft tissue around the knee, excluding the cases of postamputation, and discuss about the recipient vessels that can be used.

Reconstruction of the lower extremity using free flaps

Background

The aim of lower-extremity reconstruction has focused on wound coverage and functional recovery. However, there are limitations in the use of a local flap in cases of extensive defects of the lower-extremities. Therefore, free flap is a useful option in lower-extremity reconstruction.

Methods

We performed a retrospective review of 49 patients (52 cases) who underwent lower-extremity reconstruction at our institution during a 10-year period. In these patients, we evaluated causes and sites of defects, types of flaps, recipient vessels, types of anastomosis, survival rate, and complications.

Results

There were 42 men and 10 women with a mean age of 32.7 years (range, 3-72 years). The sites of defects included the dorsum of the foot (19), pretibial area (17), ankle (7), heel (5) and other sites (4). The types of free flap included latissimus dorsi muscle flap (10), scapular fascial flap (6), anterolateral thigh flap (6), and other flaps (30). There were four cases of vascular complications, out of which two flaps survived after intervention. The overall survival of the flaps was 96.2% (50/52). There were 19 cases of other complications at recipient sites such as partial graft loss (8), partial flap necrosis (6) and infection (5). However, these complications were not notable and were resolved with skin grafts.

Conclusions

The free flap is an effective method of lower-extremity reconstruction. Good outcomes can be achieved with complete debridement and the selection of appropriate recipient vessels and flaps according to the recipient site.

Scalp and forehead reconstruction

The treatment of scalp and forehead defects is challenging. There are few cases in which an untreated scalp defect can heal by secondary intention. However, lack of adequate treatment can also lead to fatal consequences. Adequate judgment and treatment of a defect on the scalp are therefore mandatory. There are many options to reconstruct a scalp defect. Each option has its role in the reconstruction repertoire. Various factors need to be considered when choosing the method to be used. These factors include etiology and the size of the defect, age and general health of the patient, as well as the situation at the hospital/unit where the treatment is performed. In this article, different reconstruction methods are presented, and guidelines for the selection of the various options are provided.

Shank vessel injuries: the forgotten vascular injuries

INTRODUCTION

Vascular injuries in branch vessels of the popliteal artery, such as the tibioperoneal trunk, and shank vessels, such as anterior, posterior tibial, and peroneal vessels, occur in both blunt and penetrating trauma. Their management has evolved significantly in the past few decades. While their incidence is variable, limb loss and morbidity remain significant.

MATERIAL AND METHODS

Physical examination, along with measuring an Ankle-Brachial Index (ABI), is still sometimes all that is required for diagnosis and can expeditiously triage those that require urgent operation. Despite our technological advancements and newer algorithms for lower extremity vascular trauma, operative intervention and exposure still remain difficult and pose a great challenge for surgeons that normally do not operate on this area.

CONCLUSIONS

Shank vessel injuries still comprise a significant proportion of combat and civilian vascular injuries, and modern advances have led to a dramatic decrease in amputation rates.

Selection of the recipient vein in microvascular flap reconstruction of the lower extremity: analysis of 362 free-tissue transfers

Venous insufficiency is the most common cause of re-exploration in free-tissue transfers to the lower extremity. There is currently no consensus regarding the best approach to recipient vein selection. This study was designed to evaluate whether the type of venous system or the number of recipient veins would impact flap outcomes after microsurgical lower-extremity reconstruction. A retrospective study was conducted in 362 free-tissue transfers for lower-extremity reconstruction between 2003 and 2008. Flap outcomes were evaluated according to the selection of recipient vein system and number of veins. The deep venous system (80.4%) was more frequently selected than the superficial venous system (12.1%) or the combination of both systems (7.5%). In addition, one vein (65.5%) was more commonly used for anastomosis than two veins (34.5%). A total of 26 flaps (7.2%) presented with postoperative venous insufficiency. Male patients, composite defects including bones and the use of bone flaps presented higher rates of venous insufficiency with statistical significance. However, no significant differences were found among the different groups related to the age of patients, co-morbidities, aetiology, location of the defects or timing of reconstruction after trauma. The superficial venous system group was associated with a higher rate of venous insufficiency and partial flap loss compared with the deep venous system group (p = 0.036 and 0.018, respectively). One-vein-anastomosis flaps were associated with statistically significant fewer complete flap failure in comparison with two-vein-anastomosis flaps (p = 0.014). In conclusion, the assessment of recipient vein parameters by surgeon's experience is the best predictor of flap outcome in lower-extremity reconstruction. In our cohort of patients, the deep venous system was more reliable than the superficial venous system, but the use of more than one vein for anastomosis did not correlate with better flap outcomes.

Multiple spurting test in microsurgical reconstruction of the lower extremities

Appropriate recipient artery is essential for the success of free flap reconstruction, however the selection could be difficult in a traumatized lower extremity. To detect unnoticed damage of the recipient artery, vascular integrity should be verified. For that purpose, we propose a simple and effective evaluation method, called Multiple Spurting Test (MST) this test esteems the dynamic status of the recipient arteries by measuring the length of arterial spurting. All the microsurgeons usually do something like MST: but it is not a standardized test yet.This study analyzed if this test could be a practical method in searching a safe recipient artery during microsurgical reconstruction of lower extremity. MST was employed in 163 flaps, all for lower extremity reconstruction. Fifteen flaps were re-explored in this series. Six of them had arterial problems, three in Anterior Tibial Artery (ATA), two in Posterior Tibial Artery (PTA) and one in Sural Artery (SA). The overall series' re-exploration rate, due to different complications, was 7% when ATA has been the recipient vessel, 7.6% with PTA and 30.7% with SA. Both ATA and PTA found equally reliable after examination with MST. We do believe that MST can effectively decrease the incidence of arterial complications and flap failure. Using this method, it is easier to choose a safe recipient artery for revascularization.

Lower extremity arterial injury patterns and reconstructive outcomes in patients with severe lower extremity trauma: a 26-year review

BACKGROUND

Management of severe traumatic lower extremity injuries remains a considerable challenge. Free tissue transfer is now a standard part of reconstruction for Gustilo IIIB and IIIC injuries. There is limited information on arterial injury patterns in this population. We undertook a review of our experience to gain insight on vascular injury patterns and surgical outcomes.

STUDY DESIGN

A 26-year retrospective analysis was performed of all lower extremity Gustilo IIIB and IIIC injuries requiring microvascular reconstruction at New York University Medical Center. Patient demographics, Gustilo classification, angiographic findings (conventional/computed tomographic angiography/magnetic resonance angiography), recipient vessels, elapsed time from injury, flap choices, and outcomes were examined.

RESULTS

Two hundred twenty-two free flaps on 191 patients were performed from September 1982 until March 2008. There were 151 males and 40 females ranging in age from 4 to 83 years (median age 33 years). Patients sustained either Gustilo IIIB (170 patients) or IIIC (21 patients) open fractures. One hundred fifty-four patients had angiograms (78.2% IIIB, 100% IIIC). Sixty-six (42.9%) had normal 3-vessel runoff and 88 (57.1%) were abnormal. Sixty-one patients (31.9%) had anterior tibial injuries, 17 patients (8.9%) had posterior tibial injuries, and 30 (15.7%) had peroneal injuries. Sixty-three complications occurred (11 early thrombosis, 33 requiring secondary procedures, and 10 requiring amputation).

CONCLUSIONS

Angiography of severe lower extremity injuries requiring free flap reconstruction usually revealed arterial injury and is generally indicated. In our experience, the anterior tibial artery is most commonly injured and the posterior tibial artery is most likely to be spared and used as a recipient.

Free tissue transfer for lower extremity reconstruction: a study of the role of computed angiography in the planning of free tissue transfer in the posttraumatic setting

BACKGROUND

Computed tomographic angiography can be used as a means of assessing lower leg vasculature before performing free tissue transfer, but its reliability within a trauma setting has not been evaluated. The aim of this study was to examine the findings of preoperative computed tomographic angiography and correlate these findings to flap survival and limb salvage.

METHODS

Seventy-six consecutive lower extremity trauma patients underwent preoperative computed tomographic angiography before free flap reconstruction. Arterial inflow, venous outflow, and the incidence of traumatic occlusion were recorded. Flap survival rates, limb salvage, and postoperative complications were noted.

RESULTS

There were no complications associated with the computed tomographic angiography procedure. Computed tomographic angiography demonstrated normal vascular anatomy in 40 patients (52.6 percent), anatomical variants in seven patients, and atherosclerotic occlusive disease in six patients. Traumatic arterial occlusion was identified in 22 patients (28.9 percent). Flap failure was seen in five patients and the limb salvage rate was 94.7 percent. All four of the limbs amputated had at least a single artery occluded on preoperative computed tomographic angiography; preoperative arterial occlusion was found to be a significant predictor of limb loss (p < 0.05).

CONCLUSIONS

The incidence of single-vessel traumatic arterial occlusion within traumatized lower limbs undergoing free tissue transfer may be as high as 29 percent. Computed tomographic angiography provided excellent visualization of lower extremity vasculature, and its routine use for trauma patients is safe. Flap failure rates were low when using this technique for preoperative planning. Flap failure occurred only in patients with evidence of arterial injury. Evidence of arterial occlusion on computed tomographic angiography may be a risk factor for limb loss.

Microvascular free tissue transfer in reconstruction of the lower limb

Reconstruction of the lower extremity using microvascular free tissue transfer has been adopted as a routine procedure since the 1980s. Success rates in overall free tissue transfer are now as high as 98%. In the lower limb, however, the failure rate has been reported to be as high as 15 to 20%. A review of 50 consecutive microvascular free flaps to the lower extremity was carried out in the Ulster Hospital Belfast. The indication for surgery, the flap type, the recipient vessel, re-exploration rate, complication rate, success rate and the changing pattern in management during the first six years of a single consultant's practice was assessed. Six patients (12%) were re-explored for anastomotic complications or haematoma. Thrombosis of the arterial anastomosis was noted in one case, venous thrombosis in two and haematoma under the flap in the remaining three cases. Salvage was successful in four cases, thus producing an overall success rate of 96%.

Free Tissue Transfer to the Lower Extremity Distal to the Zone of Injury: Indications and Outcomes over a 25-Year Experience

BACKGROUND

Microvascular free flap anastomoses performed for lower extremity reconstruction are traditionally proximal to the zone of injury. The authors assessed the feasibility and outcomes of microvascular free flaps with anastomoses performed distal to the zone of injury.

METHODS

The authors retrospectively reviewed all microvascular free flaps performed at their institution over the past 10 years for lower extremity reconstruction and compared this group with their previously published experience (January of 1979 through August of 1995). Between September of 1995 and May of 2005, 119 flap procedures were performed for lower extremity reconstruction. Twenty-eight flaps (24 percent) were anastomosed distal to the zone of injury and 87 (76 percent) were anastomosed proximally. There were insufficient data on the location of the anastomosis for four free flaps (all successful).

RESULTS

Twenty-seven of 28 distal microvascular free flaps were successful (96 percent); two (7 percent) required emergent postoperative reexploration of the anastomosis. Of the 87 proximal flaps, 79 (91 percent) were successful and eight (9 percent) failed. There was no statistically significant difference in the success rate of microvascular free flaps between the proximal and distal anastomosis groups (p = 0.30, Fisher's exact test). Combined with the data from the authors' previous series (January of 1979 to August of 1995), there were 63 free flaps with anastomosis performed distal to the zone of injury; 61 (97 percent) were successful.

CONCLUSION

The authors' extensive 25-year experience with lower extremity reconstruction demonstrates that in appropriately selected patients, free tissue transfer to recipient vessels distal to the zone of injury is reliable and in certain cases preferable.

Muscle Flaps in the Treatment of Osteomyelitis of the Lower Extremity

Thirty three consecutive patients with chronic osteomyelitis and deficient soft tissue coverage treated with a muscle flap from 1991-1998 were reviewed retrospectively. Osteomyelitis was diagnosed by positive bone cultures and radiographic changes consistent with osteomyelitis. Osteomyelitis was divided into localized <50% diameter: 24 patients and diffuse >50% diameter or infected nonunion: 9 patients. The average age was 38 (18-74). The cause of the osteomyelitis was open fracture 23, closed fracture and open reduction internal fixation 5, gunshot wound 3, burn 1, and chronic venous stasis ulcer 1. Localized osteomyelitis was treated with saucerization and coverage with a free or rotational muscle flap. Pandiaphyseal osteomyelitis was treated with a complete diaphysectomy in 3, and wide saucerization in 2. Twenty three patients were treated with a free flap and 10 with a rotational flap.A reconstructive success was considered a limb that allowed full weight bearing with a stable wound, no drainage and no recurrence of infection. Patients were evaluated for risk factors: malnutrition, renal or liver failure, alcohol abuse, immune deficiency, chronic hypoxia, malignancy, diabetes, age over 70, steroid therapy, tobacco abuse, or drug abuse. Patients were followed an average of 34 months (12-58) after surgery. A reconstructive success was achieved in 91% (20/22) of patients with local osteomyelitis and in 56% (5/9) of patients with diffuse osteomyelitis (p < 0.05). A reconstructive success was achieved in 88% (7/8) patients with no risk factors and in 78% (18/23) of patients with one or more risk factors (not significant p = 0.05).

Microvascular anastomosis through the tibial tunnel: a new technique in free-tissue transfer to the leg

Free-tissue transfer to a severely traumatized leg has a high rate of vascular complications. We present three successful cases using a new technique of microvascular anastomosis through the tibial tunnel. Because of the unavailability of anterior tibial artery due to posttraumatic vascular disease, donor vascular pedicles were passed posterior to the tibia through the tibial tunnel and anastomosed to the posterior tibial artery or its branch in an end-to-end fashion. The flaps survived perfectly, without any vascular complication. This technique represents a safe route, and the shortest route, to an expected anastomosis point. Our technique is indicated especially in cases with a single-vessel leg.

Vascular complication in free tissue transfer to the leg

The lower-extremity free flap has a high incidence of vascular complication. A retrospective study of 70 free flap transplants in 70 patients (1987-2000) was conducted to investigate factors leading to vascular complication and free flap failure. The overall success rate was 92% (64 of 70 flaps); the incidence of vascular complications was 22% (16 of 70 flaps). Among 16 complicated flaps, 7 were transferred in severely crushed legs, and 4 were in multioperated legs attributable to chronic osteomyelitis. Venous thrombosis occurred in 12 flaps (86%). The success rate of the patients operated on at Yamaguchi University Hospital was higher (96%) than at other hospitals tested. The key factors contributing to improved outcome in free tissue transplantation in the leg were careful preoperative planning for highly traumatized legs and proper selection of the recipient vein and of the hospital at which immediate reexploration can be performed for vascular complicated flaps.

Free tissue coverage of chronic traumatic wounds of the lower leg

Thirty-eight consecutive patients who underwent 42 free flaps for chronic wounds of the lower leg were identified over an 11-year period. All wounds were open for a minimum of 1 month (mean, 40 months; median, 8 months; range, 1 month to 30 years). The average age was 37 years (range, 7 to 68 years), there were 31 male patients and seven female patients, and the average follow-up time was 30 months (range, 12 to 72 months). The original injury was an open fracture in 28 patients, wound dehiscence after open reduction and internal fixation of a closed fracture in nine patients, and a shrapnel wound in one patient. A total of 23 patients had osteomyelitis, which was classified as local (involving less than 50 percent of the bone diameter) in 15 patients and as diffuse (involving greater than 50 percent of the bone diameter or infected nonunion) in eight patients. The wounds were treated with sequential debridement, antibiotics, and flap coverage. Ancillary procedures included antibiotic beads in 18 patients, saucerization in 16, Ilizarov bone transport in three, calcanectomy in two, and fibular resection and ankle fusion in one. Thirty-four of 42 flaps survived, four having undergone a repeat free flap. There were three failures out of 25 flaps (12 percent) among those with a normal angiogram and five failures out of 15 flaps (33 percent) among those with an abnormal angiogram (p > 0.05). The failure rate of those with osteomyelitis was six of 26 (23 percent) versus two of 26 (13 percent) for those without osteomyelitis (p > 0.05). Successful reconstruction (bone healed, patient ambulatory and infection-free) was achieved in 33 of 38 patients (87 percent). The failure of reconstruction for those patients with osteomyelitis was four of 23 (22 percent) versus one of 15 (7 percent) for others (p > 0.05). The failure rate of flaps in patients with diffuse osteomyelitis was three of eight (38 percent) versus two of 30 for others (7 percent, p = 0.053). The presence of diffuse osteomyelitis was associated with a lower rate of successful limb reconstruction. An abnormal angiogram and the presence of osteomyelitis both were associated with a lower rate of successful limb reconstruction, but this was not significant, probably because of the small size of the cohort.

The outcome of failed free flaps in head and neck and extremity reconstruction: what is next in the reconstructive ladder?

The indications for free flaps have been more or less clarified; however, the course of reconstruction after the failure of a free flap remains undetermined. Is it better to insist on one's initial choice, or should surgeons downgrade their reconstructive goals? To establish a preliminary guideline, this study was designed to retrospectively analyze the outcome of failed free-tissue transfers performed in the authors hospital. Over the past 8 years (1990 through 1997), 3361 head and neck and extremity reconstructions were performed by free-tissue transfers, excluding toe transplantations. Among these reconstructions, 1235 flaps (36.7 percent) were transferred to the head and neck region, and 2126 flaps (63.3 percent) to the extremities. A total of 101 failures (3.0 percent total plus the partial failure rate) were encountered. Forty-two failures occurred in the head and neck region, and 59 in the extremities. Evaluation of the cases revealed that one of three following approaches to handling the failure was taken: (1) a second free-tissue transfer; (2) a regional flap transfer; or (3) conservative management with debridement, wound care, and subsequent closure by secondary intention, whether by local flaps or skin grafting. In the head and neck region, 17 second free flaps (40 percent) and 15 regional flaps (36 percent) were transferred to salvage the reconstruction, whereas conservative management was undertaken in the remaining 10 cases (24 percent). In the extremities, 37 failures were treated conservatively (63 percent) in addition to 17 second free flaps (29 percent) and three regional flaps (5 percent) used to salvage the failed reconstruction. Two cases underwent amputation (3 percent). The average time elapsed between the failure and second free-tissue transfer was 12 days (range, 2 to 60 days) in the head and neck region and 18 days (range, 2 to 56 days) in the extremities. In a total of 34 second free-tissue transfers at both localizations, there were only three failures (9 percent). However, in the head and neck region, seven of the regional flaps transferred (47 percent) and four cases that were conservatively treated (40 percent) either failed or developed complications that lengthened the reconstruction period because of additional procedures. Six other free-tissue transfers had to be performed to manage these complicated cases. Conservative management was quite successful in the extremities; most patients' wounds healed, although more than one skin-graft procedure was required in 10 patients (27 percent). In conclusion, a second free-tissue transfer is, in general, a relatively more reliable and more effective procedure for the treatment of flap failure in the head and neck region, as well as failed vascularized bone flaps in the reconstruction of the extremities. Conservative treatment may be a simple and valid alternative to second (free) flaps for soft-tissue coverage in extremities with partial and even total losses.

Free flap to the arteria peronea magna for lower limb salvage

A 36-year-old woman sustained an amputation of her right leg at the thigh level and a degloving injury of her left foot and ankle region in an accident during a suicide attempt. Primarily, her left foot was covered with a split skin graft, resulting in a soft-tissue defect at the medial malleolus and at the calcaneus bone. Reconstruction was planned with a free latissimus dorsi muscle flap. Preoperative examinations revealed an arteria peronea magna with a hyperplastic peroneal artery solely providing arterial blood supply to the foot. The arteria peronea magna divided into two branches proximal to the upper ankle joint, replacing the dorsal pedis artery and the medial plantar artery. Tibial posterior and tibial anterior arteries were hypoplastic-aplastic. Microvascular end-to-end anastomoses of the flap vessels to the medial branch ("medial plantar artery") of the arteria peronea magna and its concomitant vein at the medial malleolar bone level were successfully performed. The postoperative course was uneventful. Four weeks postoperatively, the patient started walking assisted by a prosthesis on her right thigh stump. This experience demonstrates that even in a case of arteria peronea magna, free flap surgery for lower limb salvage is a reliable and worthwhile method.

Algorithm for recipient vessel selection in free tissue transfer to the lower extremity

The proper selection of a recipient vessel is essential for the success of free tissue transfer, especially when the transfer is to the lower extremity. However, a general agreement on which vessel to use has not been reached yet. Conflicting data have been reported on the survival and outcome of the transferred flaps, depending on the vessel used or the location of anastomosis. The aim of this study was to identify the patterns and problems in the selection of recipient vessels for free tissue transfer to the lower extremity and to establish a general guideline for proper selection. From September of 1990 to December of 1997, 50 consecutive, microvascular, free tissue transfers were performed on the lower extremity. The causes requiring soft-tissue coverage included trauma (25), unstable scar (11), chronic osteomyelitis (7), and tumors (7). The mean follow-up period was 22.4 months (range, 2 to 41 months). In 25 cases, the posterior tibial vessel was used as the recipient vessel. The microvascular anastomosis was done proximal to the zone of injury in 45 cases. The two most important factors in the selection of a recipient vessel are the site of injury and the vascular status of the lower extremity. Less important factors include the flap to be used, method, and site of microvascular anastomosis. All the currently feasible options for recipient vessels are included, and the opinions of other surgeons are reviewed. A general guideline is established, and an algorithm for the proper selection of a recipient vessel is proposed. This algorithm is a fast and convenient guide for evaluating the wound and planning the free flap to the lower extremity.

Value of routine angiography before traumatic lower-limb reconstruction with microvascular free tissue transplantation

From November 1993 to June 1997, long-bone defects in 40 trauma patients were reconstructed with free osteoseptocutaneous fibula flaps. To determine the necessity of routine angiography in traumatized lower limbs before free flap transplantation, a prospective study was carried out. The study subjects were 34 patients, 25 males and 9 females, with an average age of 40.6 years. Reconstruction was performed primarily for bone defects after Gustillo type III b open fractures in 17 patients and secondarily for malunion and osteomyelitis in 17 patients. Reconstructed bone defects included 25 tibias and 9 femurs. Normal pedal pulses were palpable in 31 patients. Angiographic findings were abnormal in seven patients. In the three patients with abnormal pedal pulses, the particular nonpalpable pulses correlated with the vascular lesions shown in the angiograms (one in the tibial anterior artery and two in the tibial posterior artery). Four patients with either injury of the peroneal artery (three cases) or pseudoaneurysm of the tibial anterior artery (one case) had normal pedal pulses. In all patients, microvascular transplantations were performed successfully. Our study demonstrates the importance of thorough clinical evaluation. Preoperative angiography of the injured lower limbs did not provide relevant additional informations in this series. Familiarity with all available techniques makes it possible to cope with almost any difficult posttraumatic vascular condition. Routine recipient-site angiography before microsurgical reconstruction, therefore, seems unjustified.