Influence of BMI, Age, and Gender on the Thickness of Most Common Thinned Flaps

The Superficial Circumflex Iliac Artery Perforator Flap for Devastating Hand Injuries in Obese Patients

INTRODUCTION

Blast injuries to the hand, such as those from fireworks, are debilitating and life altering. Often, because of the nature of the injury, there is a need for soft tissue and skin coverage. However, in the increasingly obese American population, free flaps often are too bulky for functional hand coverage. In this study, we present a series of 7 patients who underwent the superficial circumflex iliac artery perforator (SCIP) flap for upper extremity reconstruction with improvement in cosmesis, including a primarily repaired donor site, as well as an overwhelmingly high return to work with minimal revision surgery necessary.

METHODS

All patients who underwent a SCIP for hand injuries from a blast were included. Flaps were harvested based on previously described methods. A single attending surgeon performed all surgeries. All patients were followed for at least 6 months. Preoperative and postoperative characteristics were described.

RESULTS

A total of 7 patients were included in this study. Ages ranged from 16 to 58 years and body mass index from 19 to 48 kg/m 2 . More than half of the patients had a body mass index greater than 30 kg/m 2 . All donor sites were primarily closed. Five patients returned to their preinjury work. Three patients had neurotized flaps with return of protective sensation. Three patients required revision surgery; all 3 had liposuction, and 1 had additional flap advancement surgery.

CONCLUSION

The SCIP flap is a versatile flap that can be used in hand reconstruction in blast injuries with good functional outcome and improved cosmesis compared with other perforator flaps for the upper extremity.

Proximal peroneal perforator flap, cadaveric study, and clinical applications for shallow defect reconstructions

PURPOSE

Peroneal artery perforator offers a versatile range of microvascular tissue transfer methods from local flaps to vascularized osteocutaneous fibula flaps. It is one of the few flaps that can cover shallow defects that require thin and pliable skin paddles, such as in hands and feet (Han et al., 2018). The proximal region of the lower leg offers such flexible and thin flap compared to the middle and distal lower leg (Winters & de Jongh, 1999). However, the anatomy of the proximal peroneal artery perforator is relatively unknown in literature and its proximity to the common peroneal nerve (CPN) has not yet been studied. This study conducted a cadaveric study and put it in application into clinical settings.

METHODS

Twenty lower leg specimens were dissected according to the methods of clinical proximal peroneal artery perforator flap harvest. Perforators arising in the proximal lower leg area of between 20 and 40 percentile of fibular length were inspected. Perforator length, location from fibular head, course, and location of CPN were recorded. Clinical reconstruction cases using the proximal lateral lower leg were analyzed. Six patients between the ages of thirty and seventy were included. Five cases were due to trauma, and one from mass excision, but all required thin and pliable flaps for reconstructions in hands or feet. Flaps were designed concentrical oval shapes, and harvest was done similarly to cadaveric perforator dissection, but perforator dissection was done only up to the required pedicle length. Perforator length, flap size, thickness, and long-term complications were recorded.

RESULTS

Among 20 specimens, a total of 20 perforators were found in 18 cadavers (90%). Two specimens showed no perforators while two specimens showed multiple perforators. The perforators were located at an average of 101 mm from fibular head, with an average length of 55 mm ranging from 20 to 153 mm. The average size of perforator at origin was 2.0 mm, ranging from 1.0 to 3.6 mm. 45% showed septocutaneous course and 55% intramuscular course. Two out of 20 perforators were shown to arise from source vessels other than the peroneal artery. All clinical cases were successful without complications or debulking for contour shaping. Flap sizes ranged from 15 to 40 cm² . Largest flap width was 5 cm, and all donor sites were primarily closed without complications. One year of follow-up showed no complications.

CONCLUSION

Proximal peroneal artery perforator flap provides a reliable pedicle for a versatile tissue transfer. This study shows that the perforators of the proximal lateral lower leg often arise from vessels other than the peroneal artery, such as the anterior tibial artery or popliteal artery, as had been previously reported (Winters & de Jongh, 1999). Although the source vessel varies, perforator anatomy is at a safe distance from CPN. This variation of source vessels suggests a change in nomenclature to "proximal peroneal perforator flap." The clinical applications of this flap showed that it can be effectively used for reconstructions of shallow defects, such as in the hands and feet without secondary procedures for debulking.

Subcutaneous adipose tissue thickness around the ASIS area for human body models in reclined positions

OBJECTIVE

Subcutaneous adipose tissue (SAT) thickness above the anterior superior iliac spine (ASIS) influences belt fit of a vehicle occupant. To improve finite element (FE) human body models and their application assessing future seating positions in cars, there is a need for more detailed data.

METHODS

Anthropometric input data were used to statistically model a lower limit of the SAT thickness in the area around the ASIS (at the ASIS or in the groin) extracted from 102 postmortem computed tomography (pmCT) data sets (56 males and 46 females). Additionally, 2 pmCT scans of 1 male individual in both supine and sitting conditions were used to estimate change in SAT thickness by position.

RESULTS

Distributions and locations of minimum values for SAT thickness were derived for males and females. Sex, age, and body mass index (BMI) remained in a linear regression model for the minimum SAT thickness in the ASIS area. Thirty-seven percent of the variance in the SAT distribution of the sample can be explained by these input variables. The individual with data in supine and sitting positions showed an SAT thickness value above the ASIS 6 times higher in the sitting position than in the supine position.

CONCLUSIONS

Individual factors influence SAT thickness around the ASIS in addition to BMI, sex, and age. The presented values need to be regarded as a lower limit of SAT thickness, because in 63% the minimum was found in the groin area and the measurements were performed in a supine position. The increase in SAT thickness in a sitting position compared to supine seen in the case example shows the need for further data acquisition to establish a transfer function interpolating between both positions. The SAT thickness minimum values in the ASIS area shown in this study can provide valuable input for soft tissue modeling in human body models with the aim to analyze seat belt fit and to computationally assess lap belt and occupant interaction sensitivity to SAT tissue thickness under load. This might be crucial in reclined sitting positions in automated driving.