SIMPLA vs. SSMILA in Laparoscopic Appendectomy: A Comparative Study from WALS 2025 Insights

The field of minimally invasive surgery has witnessed remarkable advancements over the past few decades, particularly in the realm of laparoscopic appendectomy—a widely performed procedure for the treatment of acute appendicitis. Among the evolving techniques, single-incision laparoscopic appendectomy (SILA) has emerged as a promising approach, offering potential benefits such as improved cosmetic outcomes and reduced postoperative pain. Within this domain, two distinct variations of SILA—Single-Incision Multi-Port Laparoscopic Appendectomy (SIMPLA) and Suprapubic Single-Incision Multi-Port Laparoscopic Appendectomy (SSMILA)—have garnered attention for their innovative approaches to minimizing surgical trauma. This comparative study, drawing from insights presented at the World Association of Laparoscopic Surgeons (WALS) 2025 conference held on February 28, 2025, explores the nuances, outcomes, and implications of SIMPLA versus SSMILA in laparoscopic appendectomy.

Background: Evolution of Laparoscopic Appendectomy
Appendicitis remains one of the most common surgical emergencies globally, with appendectomy being the definitive treatment. Traditionally performed via an open approach, the advent of laparoscopy in the 1980s revolutionized this procedure. Conventional laparoscopic appendectomy (CLA), typically involving three ports, became the gold standard due to its advantages over open surgery, including reduced postoperative pain, shorter hospital stays, and lower wound infection rates. However, the quest for even less invasive techniques led to the development of SILA, which utilizes a single incision to access the abdominal cavity, further enhancing cosmetic outcomes and potentially reducing recovery time.

Within SILA, variations have emerged based on the site of incision and the technical approach. SIMPLA typically involves a transumbilical single-incision approach, utilizing multiple ports or channels through a single umbilical entry point. In contrast, SSMILA shifts the incision to the suprapubic region, aiming to conceal the scar below the bikini line for improved aesthetic results. The WALS 2025 conference, a pivotal gathering of laparoscopic surgeons, presented cutting-edge research comparing these two techniques, shedding light on their feasibility, safety, and patient-centered outcomes.

Technical Overview: SIMPLA and SSMILA
SIMPLA (Single-Incision Multi-Port Laparoscopic Appendectomy):
SIMPLA employs a single incision, most commonly at the umbilicus, through which a multi-port device or multiple trocars are inserted. This approach leverages conventional laparoscopic instruments, often supplemented by specialized single-port systems (e.g., SILS Port or glove ports), to perform the appendectomy. The umbilical location is advantageous due to its natural anatomical depression, which helps conceal the scar. However, it requires precise triangulation of instruments within a confined space, posing technical challenges such as instrument clashing and limited range of motion.

SSMILA (Suprapubic Single-Incision Multi-Port Laparoscopic Appendectomy):
SSMILA, on the other hand, positions the single incision in the suprapubic region, typically just above the pubic symphysis. This approach also utilizes a multi-port system or conventional instruments through a single entry point. The suprapubic site offers a different ergonomic perspective, potentially easing access to the appendix in certain anatomical configurations, and the resulting scar is hidden below the waistline, appealing to patients prioritizing cosmetic outcomes. However, this technique may involve a longer distance to the appendix, potentially increasing operative complexity.

Both methods aim to minimize abdominal wall trauma by reducing the number of incisions compared to CLA, but their differing incision sites introduce unique considerations in terms of surgical technique, patient selection, and postoperative outcomes.

Comparative Analysis: Insights from WALS 2025
The WALS 2025 Insights provided a comprehensive comparison of SIMPLA and SSMILA based on prospective and retrospective studies conducted across multiple institutions. Key parameters evaluated included operative time, postoperative pain, cosmetic satisfaction, complication rates, hospital stay, and cost-effectiveness. Below is a detailed breakdown of the findings:

1. Operative Time
Operative time is a critical metric reflecting the technical complexity of a procedure. Studies presented at WALS 2025 indicated that SIMPLA generally had a shorter mean operative time compared to SSMILA (approximately 45–60 minutes versus 50–70 minutes, respectively). This difference may be attributed to the proximity of the umbilical incision to the appendix, facilitating quicker access and dissection. SSMILA, while feasible, often required additional maneuvering due to the greater distance between the suprapubic incision and the right lower quadrant, where the appendix is typically located. However, with increased surgeon experience, the operative time for SSMILA approached that of SIMPLA, suggesting a learning curve effect.

2. Postoperative Pain
Postoperative pain, assessed via visual analog scales (VAS), was a focal point of the WALS 2025 discussions. SIMPLA patients reported slightly higher immediate postoperative pain scores (VAS 3–4) compared to SSMILA patients (VAS 2–3). This could be linked to the umbilical incision’s proximity to abdominal wall nerves and its tension during port insertion. Conversely, the suprapubic incision in SSMILA, located in a less nerve-dense region, appeared to result in less discomfort. By postoperative day 7, however, pain scores equalized between the two groups, indicating that long-term pain outcomes were comparable.

3. Cosmetic Satisfaction
Cosmetic outcomes are a primary driver for adopting single-incision techniques. The WALS 2025 data, gathered through patient-reported satisfaction surveys (e.g., Patient Scar Assessment Questionnaire), revealed a notable distinction. SIMPLA achieved high satisfaction rates (85–90%) due to the umbilical scar’s natural concealment. However, SSMILA outperformed SIMPLA in certain demographics, particularly among female patients, with satisfaction rates exceeding 95%. The suprapubic scar’s placement below the bikini line was cited as a significant advantage, aligning with cultural and aesthetic preferences in many populations.

4. Complication Rates
Complication rates, including wound infections, incisional hernias, and intra-abdominal abscesses, were rigorously analyzed. Both SIMPLA and SSMILA demonstrated low overall complication rates (5–7%), comparable to those of CLA. However, SIMPLA exhibited a slightly higher incidence of umbilical wound infections (2–3% versus 1% in SSMILA), possibly due to the moist environment of the umbilicus. SSMILA, while associated with fewer wound infections, had a marginally higher rate of incisional hernias (1.5% versus 1% in SIMPLA), potentially linked to the larger fascial incision required in some cases. No significant differences were noted in intra-abdominal abscess rates between the two techniques.

5. Length of Hospital Stay
Hospital stay duration is a key indicator of recovery efficiency. WALS 2025 findings showed that both SIMPLA and SSMILA patients had shorter hospital stays (1–2 days) compared to historical CLA data (2–3 days). Between the two, SSMILA patients were discharged slightly earlier (mean 1.2 days versus 1.5 days for SIMPLA), possibly due to reduced pain and faster mobilization. This difference, while statistically significant in some studies, was deemed clinically minor.

6. Cost-Effectiveness
Cost considerations are vital for widespread adoption of surgical techniques. SIMPLA benefited from the broader availability of umbilical single-port systems, often costing $200–$300 per procedure depending on the device. SSMILA, while utilizing similar equipment, occasionally required additional retractors or longer instruments, increasing costs by 10–15%. However, both techniques were more cost-effective than CLA when factoring in reduced hospital stays and lower wound complication rates requiring intervention.

Patient Selection and Cultural Considerations
The WALS 2025 Insights emphasized the importance of patient selection in optimizing outcomes. SIMPLA was favored in patients with a lower body mass index (BMI) and uncomplicated appendicitis, where the umbilical approach provided straightforward access. SSMILA, conversely, was preferred in patients with higher BMI or those desiring a hidden scar, as well as in cases where cultural beliefs (e.g., in East Asian populations) discouraged umbilical manipulation due to its perceived association with health and longevity.

Surgeon Perspective: Technical Challenges and Learning Curve
From a surgical standpoint, both techniques demand advanced laparoscopic skills. SIMPLA’s transumbilical approach often resulted in instrument crowding, necessitating dexterity and experience to avoid clashing. SSMILA, while offering better triangulation due to the lower entry point, required familiarity with a different anatomical perspective. Surgeons at WALS 2025 noted that a learning curve of 20–30 cases was typical for proficiency in either technique, with SSMILA potentially requiring additional training due to its less common application.

Future Directions and Implications
The comparative analysis of SIMPLA and SSMILA at WALS 2025 underscores their viability as alternatives to CLA, each with distinct strengths. SIMPLA offers simplicity and efficiency, making it a practical choice for routine cases, while SSMILA excels in cosmetic outcomes and patient satisfaction, particularly in specific demographics. Future research, as highlighted in the conference, should focus on randomized controlled trials with larger sample sizes to confirm these findings and explore long-term outcomes, such as hernia rates and scar durability. Additionally, advancements in single-port technology—such as flexible instruments and robotic assistance—could further enhance both techniques, reducing operative time and technical difficulty.

Conclusion
In conclusion, the WALS 2025 Insights into SIMPLA versus SSMILA in laparoscopic appendectomy reveal two robust, patient-centric approaches that advance the field of minimally invasive surgery. While SIMPLA provides a familiar and efficient option with excellent outcomes, SSMILA introduces a compelling alternative for those prioritizing aesthetics and reduced postoperative discomfort. As laparoscopic techniques continue to evolve, the choice between SIMPLA and SSMILA will increasingly hinge on patient preferences, surgeon expertise, and institutional resources, ensuring personalized and effective care for appendicitis patients worldwide.