Improving the outcome of distally based anterolateral thigh flap reconstruction: New classification and surgical guidelines

BACKGROUND

The distally based anterolateral thigh (dALT) flap is associated with a high incidence of venous congestion. This study aimed to investigate factors associated with vascular compromise to improve the outcomes.

METHODS

We retrospectively analyzed 41 dALT flap reconstructions performed between November 2010 and February 2023. The dALT flap was classified into type I, II, or III based on the origin (the descending, oblique, or transverse branch) of the chosen perforator. The distance from the pivot point to the superolateral patella, pedicle length, flap reach, complications, and loss rates were analyzed to identify different dALT flap characteristics.

RESULTS

The type Ⅰ flap had a shorter pedicle length (type Ⅰ vs. type Ⅱ, p = 0.000; type Ⅰ vs. type Ⅲ, p = 0.000) that primarily reached closer regions (distal third of the thigh anterior/lateral knee). Pedicle lengths were similar between type Ⅱ and Ⅲ flaps (p = 1.000), most of which reached more distal regions (medial/posterior knee or proximal third of the leg). However, the type Ⅲ flaps had a higher complication rate and flap loss rate, although no significant differences were observed (complication rate, p = 0.094; flap loss rate, p = 0.071).

CONCLUSIONS

To achieve more desirable outcomes using the dALT flap, preoperative assessment of flap pedicle length and proper intraoperative maneuvers that avoid compromising the reverse blood circulation are necessary.

Distally based perforator sural flaps for foot and ankle reconstruction

Distally based perforator sural flaps from the posterolateral or posteromedial lower leg aspect are initially a neurofasciocutaneous flap that can be transferred reversely to the foot and ankle region with no need to harvest and sacrifice the deep major artery. These flaps are supplied by a perforating artery issued from the deep peroneal artery or the posterior tibial artery, and the chain-linked adipofascial neurovascular axis around the sural/saphenous nerve. It is a versatile and reliable technique for soft-tissue reconstruction of the heel and ankle region with 180-degrees rotation. In this paper, we present its developing history, vascular basis, surgical techniques including flap design and elevation, flap variations in pedicle and component, surgical indications, and illustrative case reports with different perforating vessels as pivot points for foot and ankle coverage.

Reconstruction of complex soft-tissue defects around the knee joint with distally based split vastus lateralis musculocutaneous flap: a new technique

AIMS

The aim of this study was to report our experience of using distally based spilt vastus lateralis musculocutaneous flaps for soft-tissue defects around the knee joint - a new technique.

MATERIAL AND METHODS

Cadaver dissection studies were conducted in three cadavers to demonstrate perforators entering the lower third of the vastus lateralis muscle arising from the superior lateral genicular artery. Its application in eight clinical cases for the reconstruction of soft-tissue defects around the knee joint is reported.

RESULTS

Seven out of eight flaps survived well without any flap loss. One flap with a skin island measuring 12 × 20 cm suffered a loss of 2 cm distally. This was later treated with skin grafting. Six out of eight donor sites were closed primarily. Six patients achieved full functional range of motion by 3 months. One patient had a 10° limitation of knee extension. One patient had foot drop due to primary injury and walks with a limping gait.

CONCLUSIONS

This flap is a new reconstructive option for knee defects. It can reach distally up to the tibial tuberosity and does not require an intraoperative change of position. The donor site can be closed primarily and is hidden inside the clothing. The function of the knee is not affected as the majority of the muscle is kept in continuity.

Distally-based osteocutaneous dorsal metatarsal artery flap for hallux reconstruction

Reconstruction of complex defects of the distal portion of the foot remains a challenging problem for plastic surgeons. A traumatic case is presented where reconstruction of a complex plantar defect of the hallux was achieved using a distally-based osteocutaneous metatarsal artery flap based on the second dorsal metatarsal artery. Local flap repair is a viable reconstructive option for complex defects of the plantar surface of the forefoot.

Distally based perforator flaps for reconstruction of post-traumatic defects of the lower leg and foot. A review of the anatomy and clinical outcomes

STUDY AIMS

To report the surgical anatomy of the perforator arteries at the lower leg, analyse clinical outcomes in previous studies, and forward methodological recommendations for future studies of post-traumatic perforator flap reconstructions.

METHODS

A study sample of 640 human patients drawn from 24 clinical reports was included for review. The sample comprised of four subsets: sural flap reconstructions (n=257), saphenous flaps (n=122), supramalleolar flaps (n=92), and propeller flaps (n=169).

RESULTS

Statistical analysis of samples from anatomical studies documents significant differences in the perforator distribution from the tibial and peroneal artery; peroneal perforator arteries are randomly organised whereas tibial artery perforators are clustered at three definite levels. The failure rates in clinical studies ranged from 0% to 6%, being lowest for supramalleolar flap reconstructions and highest for saphenous flaps; however, differences between the four subsets were not statistically significant at the 95% confidence level. Due to methodological flaws, outcome comparisons in the actual study sample should be interpreted cautiously; in most clinical studies both risk variables and outcome indicators are poorly defined. The outcome of Dynamic Infrared Thermography imaging of post-transposition changes of flap perfusion is reported.

SUMMARY

Fasciocutaneous perforator flaps seem to have high survival rates and represent a feasible approach to post-traumatic reconstructions, especially in low-resource settings. A template for data gathering is recommended for higher accuracy in future comparative studies, and for scientific analysis of success and risk factors. New imaging techniques indicate a promising potential of micro-circular angiogenesis during the first two weeks after flap transpose.