Background: Trapezius hypertrophy is a significant aesthetic concern among women. Botulinum toxin has emerged as a potential treatment option for this condition. In this study, we conducted a prospective, randomized, double-blind trial to evaluate the effectiveness and safety of letibotulinumtoxinA specifically for women.

Methods: We conducted a prospective study between July 2022 and June 2023, recruiting 20 patients seeking treatment for trapezius hypertrophy. LetibotulinumtoxinA (Botulax®) was used as the neurotoxin. The patients were randomized into group A (n = 10, 40 units) and group B (n = 10, 80 units). Each group received different doses of toxin at 10 injection points along the trapezius muscle.

Results: We analyzed the contour changes in two groups and calculated the average area before and after treatment. After 12 weeks post-treatment, both groups demonstrated a decrease in the trapezius area with statistically significant differences (p = 0.011, p = 0.005). The median satisfactory score was 4, indicating a moderate level of satisfaction in both groups. No statistically significant differences or complications were observed between the groups.

Conclusion: LetibotulinumtoxinA for trapezius hypertrophy demonstrated efficacy with no differences between two experimental groups. Aesthetic concerns were addressed, enhancing shoulder and neck appearance with a high degree of satisfaction.

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 .

Background: Supermicrosurgery involving vessels ≤0.3 mm remains among the most technically demanding procedures in reconstructive surgery. Robotic platforms have shown potential to enhance precision, but their feasibility at this extreme scale requires further validation.

Methods: Apprentice surgeons (≤5 years' experience) performed rat femoral vessel (approximately 0.26-0.30 mm) anastomoses using both hand-sewn and robotic-assisted techniques across eight consecutive trials. Outcome measures included Structured Assessment of Robotic Microsurgical Skills (SARMS) scores, operative time, stitch count, and patency rate. Learning curves were assessed with cumulative summation (CUSUM) analysis, and anastomotic quality was evaluated using scanning electron microscopy (SEM).

Results: Robotic-assisted anastomosis reached proficiency earlier than hand-sewn repair (4th versus 6th trial). Although initial operative time was longer for robotic cases (1,772 ± 120 seconds versus 1,355 ± 187 seconds, p = 0.013), times equalized by the 5th trial and decreased by 42% by the 8th (1,026 ± 58 seconds versus 1,023 ± 73 seconds, p = 0.959). Stitch counts were higher in later robotic trials (4.2 ± 0.6 versus 3.5 ± 0.5, p = 0.015). Both groups achieved 100% patency by the 4th trial. CUSUM and SEM analyses confirmed a steeper learning curve and superior anastomotic precision with robotic assistance.

Conclusion: Robotic-assisted supermicrosurgery enables earlier proficiency, enhanced precision, and reproducible anastomotic quality compared with hand-sewn techniques. Despite longer initial times, robotic performance rapidly improved, achieving equivalent efficiency with greater technical control. These findings confirm the technical feasibility of robotic supermicrosurgery at the 0.3 mm scale and support its potential role in microsurgical and lymphatic reconstruction training and clinical practice.

Supermicrosurgery is defined as microsurgical work performed on vessels smaller than 0.8 mm in diameter. This advancement enables surgical applications at finer scales, including the treatment of lymphatic disorders, minimally invasive reconstructions, small-part replantations, and perforator-to-perforator anastomoses. To facilitate these procedures, there has been significant development in ultrafine surgical instruments, microsutures, enhanced imaging and diagnostic technologies, robotic microsurgery platforms, and high-magnification microscopes or exoscopes. Supermicrosurgery represents more than just a refinement of microsurgical technique-it marks the emergence of a new field that deepens our understanding of anatomy and physiology at the microvascular level and innovative approaches to solving challenges.