Ultrasound-guided five-point injection of botulinum toxin for patients with trapezius hypertrophy

Nerve Distribution Method is Superior to the Conventional Method in BoNT-A Treatment of Trapezius Hypertrophy: A Randomized Controlled Trial

The contour of the neck and shoulder is defined by the trapezius muscle (TM). Beyond facial procedures, botulinum toxin A (BoNT-A) injections has been increasingly adopted to create a smooth shoulder line. Several studies described the intramuscular nerve branching and the pattern of perforating branch of the accessory nerve in the trapezius muscle, providing essential information for botulinum neurotoxin injection. To this date, research groups seldom perform clinical investigations, especially randomized controlled trials, that demonstrates whether BoNT-A injections using the nerve distribution method for aesthetic purposes is more effective. Patients met the criteria for inclusion were randomized to either the Nerve Distribution group (ND group) or control group. Control group patients received injection using the conventional method while ND group patients received the nerve distribution method. Photographic and ultrasonographic evaluations were carried out at baseline, one month, three months, and six months after the procedure. Patients were also required to complete a questionnaire to evaluate their feedbacks to the injection. After screening, 30 healthy young Chinese women were included. At one-month follow-up, no statistically significant difference was observed between the two methods. At the three-month follow-up, the reduction of the TM thickness for the ND group (0.21 ± 0.09 cm) was more than that for the control group (0.27 ± 0.08 cm), with p = 0.047*. Similar differences were observed for the reduction of the shoulder area proportion (p = 0.031*) and the shoulder angle (p = 0.035*). At the six-month follow-up, the reduction in TM thickness in the ND group (0.2 ± 0.09 cm) was more than that of the control group (0.28 ± 0.06 cm), with p = 0.041*. The global aesthetic improvement scale feedbacks of the two methods showed no significant difference (3.4 ± 0.71 vs 3.8 ± 0.91, p = 0.207). The patients did not experience severe side effects. Compared to the conventional injection method, the nerve distribution method is more effective in reducing the trapezius muscle thickness, shoulder area proportion, and shoulder angle at three months, and shows longer lasting effects. The results of this study introduce unique insights into the design and tailoring of treatment protocols for shoulder-line contouring using BoNT-A.Level of Evidence I This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

A Review of Aesthetic Considerations for Treating the Transgender Patient

BACKGROUND

As gender diversity becomes increasingly embraced by society, and despite growing recognition of the unique needs of transgender patients, the literature remains devoid of guidelines for gender affirming facial feminization or masculinization techniques.

OBJECTIVE

The authors seek to identify and discuss target feminine and masculine facial features, as well as an armamentarium of surgical and nonsurgical strategies to effectively address and achieve them in the transgender population.

METHODS

A search of the National Library of Medicine database (PubMed) was undertaken to identify the existing literature on gender-affirming facial feminization and masculinization techniques.

RESULTS

The importance of assessing proportional relationships between the bitemporal, bizygomatic, and bigonial distances is discussed; ideal masculine faces possess a rectangular face shape, with ratios for these 3 areas tending toward 1:1:1. Conversely, the ideal female face is heart shaped with projection at the zygoma and a tapered jawline. Strategic positioning of the cheek apex serves as an anchor in sculpting a distinctly masculine or feminine face. Other considerations include the enhancement of skin quality and implications of hormonal therapy.

CONCLUSION

The aesthetic considerations provided in this study can serve as a valuable guidance for aesthetic physicians seeking to deliver optimal care for their transitioning patients.

Ultrasonographic Analysis of Trapezius Muscle for Efficient Botulinum Toxin Type A Injection

BACKGROUND

Patients nowadays seek medical reduction of the upper trapezius muscle to achieve aesthetic pleasing necklines. Botulinum toxin type A (BoNT-A), a neurotoxin that reduces the force of muscle contraction, is widely used for shoulder contouring. However, detailed metrical data are lacking to guide clinical injection.

METHODS

Forty healthy young women were enrolled. All subjects were seated for point marking and measuring of trapezius muscle (TM) anatomical data. At marked locations, the thickness of the subcutaneous tissue, the thickness of the TM, the TM's anterior border, and the depth from the skin surface to the middle of TM were measured using a real-time ultrasound scanner. In addition, photos were taken to assess the shoulder area proportion and shoulder angle.

RESULTS

The shoulder area size among participants was 90 ± 15.2 cm2, the average area proportion was 0.55 ± 0.1, and the shoulder angle was 23.12° ± 2.9°. Ultrasonography data reveal that the thickness of the subcutaneous tissue, the thickness of the TM, and the depth from the skin surface to the middle of TM all thickened from the anterior line to the posterior line (P < 0.001). The length of the TM extending forward was 1.47 ± 0.4 cm (range 0.51-1.31 cm). To better evaluate the appearance of the trapezius muscle, we constructed a grading system correlated to shoulder angle.

CONCLUSION

In this study, ultrasonography and photos were applied to assess the TM's anatomical features. Trapezius hypertrophy was described on a scale from 0 to 2 based on the shoulder angle. The findings of the present study provide a practical clinical guidance for precise and efficient BoNT-A administration.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .