The Role of the Distal Runoff Vessel of the Descending Branch of the Lateral Circumflex Femoral System in Anterolateral Thigh Flap Surgery: A Case Series and Literature Review

Is the oblique branch of the lateral circumflex femoral artery a common variant?

The oblique branch of the lateral circumflex femoral artery, a short branch of the deep femoral artery, is highly prevalent (32-46%) and is usually considered a normal variant, although this is still controversial. This study aimed to evaluate whether the oblique branch of the lateral circumflex femoral artery is a variant. We reviewed medical record data of patients with skin and soft tissue defects of the extremities who underwent flap repair using free anterolateral thigh (ALT) flaps at our hospital in 2019. The anatomical characteristics of the flaps were examined intraoperatively by high-frequency color Doppler ultrasound. A total of 153 ALT flaps from 146 patients were included. Among the branches, 232 (73.7%) were oblique branches, and 83 (26.4%) were descending branches. Of the 232 oblique branches, 141 (60.8%) were from septocutaneous branches, and the other 83 (39.2%) were from musculocutaneous branches. In addition, 20 (24.1%) descending branches were from septocutaneous branches, and the other 63 (75.9%) were from musculocutaneous branches. Analyzing the prevalence of the oblique branch in septocutaneous branches, more than half of the patients had oblique branches rather than descending branches. The high proportion of oblique branches from septocutaneous branches (median: 100 (0-100) vs. 0 (0-50), p = 0.002) supports the understanding that the oblique branch is a normal anatomical element rather than a variant. The main type was the intramuscular branches, which required significantly less time for flap harvesting. The oblique branch may be the preferred vascular pedicle for free ALT flaps.

Large wounds reconstruction of the lower extremity with combined latissimus dorsi musculocutaneous flap and flow-through anterolateral thigh perforator flap transfer

BACKGROUND

Management of large wounds of the lower extremities remains a challenge for plastic and reconstructive surgeons. Herein, a surgical technique and clinical algorithm using the combined transfer of a latissimus dorsi (LD) musculocutaneous flap and flow-through anterolateral thigh (ALT) perforator flap for the treatment of extensive soft-tissue defects is described.

METHODS

From January 2012 to September 2018, 12 patients (six men and six women) aged 6-37 years, sustained injuries in road traffic accidents with large soft-tissue defects in the lower extremities. Seven cases were Gustillo Anderson type IIIB open fractures and two cases were Gustillo Anderson type IIIC open fractures. Two wounds were located in the knee joint, four in the calf, and six in the ankle and foot. The skin defect size ranged from 25 × 20 cm² to 36 × 25 cm² . All patients in this series underwent reconstruction using combined transfer of the LD musculocutaneous flap and flow-through ALT perforator flap, wherein the LD was attached through its pedicle to the distal continuation of the ALT flap.

RESULTS

The size of the flow-through ALT perforator flaps ranged from 13.5 × 6.5 cm² to 31 × 8.5 cm² . The size of the LD musculocutaneous skin paddle ranged from 25 × 6 cm² to 34 × 7 cm² , and that of the muscle paddle ranged from 13 × 3.5 cm² to 30 × 11 cm² . One patient experienced postoperative thrombosis of the venous pedicle, and the flap was salvaged after emergency re-exploration and thrombectomy. No other complications were observed postoperatively. The mean follow-up period was 26.8 months. All patients were able to ambulate independently at the end of the follow-up period.

CONCLUSIONS

The combined transfer of the LD musculocutaneous flap and flow-through ALT perforator flap ensured adequate surface coverage, making it a feasible procedure for large soft-tissue defects.

Temporary Ectopic Implantation of an Amputated Leg Using the Distal Runoff Vessel of the Anterolateral Thigh Flap Followed by Subsequent Prefabricated Chimeric Replantation

AIM

Infrapopliteal replantation is indicated in selected patients. When the patient is hemodynamically unstable or the amputation site is severely contaminated, temporary ectopic implantation of the amputated limb is an option. To the best of our knowledge, this is the first case report using the distal runoff vessel of the anterolateral thigh flap for temporary ectopic implantation of an amputated leg followed by replantation with the prefabricated anterolateral thigh flap.

PATIENT AND METHODS

A 28-year-old male driver had left leg avulsion amputation after a car accident. Because of concerns about the high-energy trauma mechanism and extensive trauma zone, temporary ectopic implantation was planned to avoid a lengthy replantation procedure and to enable future replantation. The amputated leg was implanted to the thigh using the distal runoff vessel of the descending branch of the lateral circumflex femoral system in the preservation of proximal cutaneous perforator. When the patient became hemodynamically stable and the amputated stump was relatively clean and healthy, we replanted the amputated leg with the prefabricated anterolateral thigh flap on day 7.

RESULTS

The replanted leg and anterolateral thigh flap survived well after the procedure. At the 15-month follow-up, the patient could walk independently. There was no need for custom-made shoes because there was no obvious leg length discrepancy and the flap was not bulky.

CONCLUSIONS

We believe that the distal runoff vessel of the descending branch of the lateral circumflex femoral system can not only serve as a recipient site for temporary ectopic implantation but also enable the harvest of a prefabricated anterolateral thigh flap with the amputated part at the replantation stage. This prefabricated tissue containing the anterolateral thigh flap and the amputated part needs only 1 set of vascular anastomosis to accomplish replantation and simultaneous revascularization of the anterolateral thigh flap. Most importantly, this ectopically prefabricated chimeric tissue minimizes the need for extensive bone shortening after radial debridement by providing sufficient soft tissue coverage at the replantation stage.

A case series of flow-through free anterolateral thigh flap to augment the vascularity of ischaemic limbs with soft tissue defect

Introduction:

In a world of fast moving vehicles, heavy machinery and industries crush injury to limbs with vascular compromise and soft tissue defect is common. The traditional treatment is a 2 step one dealing with vascular repair and soft tissue cover separately, in the same operation. We report a series of single step vascular repair and soft tissue cover with flow through anterolateral thigh flap (ALT) flap for limb salvage.

Materials and Methods:

Ten patients with soft tissue defect and vascular injury were included in this study. A two team approach was used to minimise operative time, team one prepared the vessels and team 2 harvested the flap.

Observations and Results:

Of the ten patients operated (8 males), eight flaps were done for upper limb and two for lower limb salvage. Six anastomosis were done with ulnar vessels, two with radial and two with posterior tibial vessels. Nine extremities could be salvaged while one patient developed progressive thrombosis leading to amputation.

Conclusion:

The ALT flow-through flap is a versatile single step procedure that can be used to salvage an ischemic limb with soft tissue loss avoiding the need for interpositional vein graft.