Authors: Konstantinos Kossenas, Riad Kouzeiha, Olga Moutzouri, Filippos Georgopoulos
Categories: Review Article, Appendectomy, Single incision laparoscopic, Conventional laparoscopic surgery, Minimally invasive surgery, Experienced surgeons, Randomized clinical trials
Source: Updates in Surgery
Authors: Konstantinos Kossenas, Riad Kouzeiha, Olga Moutzouri, Filippos Georgopoulos
Three-port (trocar) laparoscopic appendectomy is the standard treatment for acute appendicitis and previous studies have compared to single-incision approach, however, they often include both pediatric and adult patients and fail to account for surgeons’ experience, leading to variability in outcomes. This systematic review and meta-analysis aims to address these literature gaps by focusing on adult patients and controlling for surgeon expertise. We conducted a comprehensive search of randomized controlled trials comparing single-incision laparoscopic appendectomy (SILA) and conventional laparoscopic appendectomy (CLA) up to November 2024. We assessed the length of hospitalization, operative duration, postoperative complications, and surgical wound infections. Data were synthesized using random-effects models to account for variability among studies. The meta-analysis included four studies with a total of 408 patients, comprising 202 in the single-incision laparoscopic appendectomy (SILA) group and 206 in the conventional laparoscopic appendectomy (CLA) group. For the length of hospitalization, no statistically significant difference was observed, with a weighted mean difference (WMD) of 0.07 days (95% CI − 0.32 to 0.47, I^2^ = 0%, p = 0.72). Similarly, the operative duration showed no significant difference, with a WMD of 4.49 min (95% CI − 7.02 to 16.00, I^2^ = 89%, p = 0.44). The analysis of postoperative complications also revealed no significant difference between the groups, with an odds ratio (OR) of 1.32 (95% CI 0.69 to 2.51, I^2^ = 0%, p = 0.40). Surgical wound infections were found to be comparable, with an OR of 1.14 (95% CI 0.46 to 2.83, I^2^ = 0%, p = 0.78). Sensitivity analysis indicated that the results were statistically significant regarding operative duration when Kim et al. was excluded from the analysis. SILA and CLA yield comparable outcomes in terms of hospitalization length, operative duration, and complications, suggesting that both techniques are viable options for the management of acute appendicitis in adults. Further studies investigating overall cosmesis, patient satisfaction, and postoperative pain are warranted to optimize surgical approaches.
PROSPERO CRD42024612596.
The online version contains supplementary material available at 10.1007/s13304-025-02112-5.
Laparoscopic appendectomy is considered the preferred surgical treatment of acute appendicitis in most cases where expertise and equipment is available, due to the fact that it results in reduced postoperative pain, shorter hospital stays, and faster recovery compared to open appendectomy (OA) [1], especially because of its minimally invasive nature [2]. However, within the realm of laparoscopic techniques, a new approach has single-incision laparoscopic appendectomy (SILA). This method aims to further minimize the invasiveness of the procedure by utilizing a single incision, typically at the umbilicus, in contrast to the three or four incisions used in conventional laparoscopic appendectomy (CLA) [3].
While some studies suggest that SILA additionally offers potential benefits such as improved cosmetic outcomes, reduced hospital costs and stays, minimizing surgical incisions and enhanced patient experience, its widespread adoption has been tempered by concerns. These concerns include increased postoperative pain particularly upon exertion, the requirement of higher doses of analgesics, greater chance of complications, longer operative times compared to the conventional laparoscopic procedure, and the technically demanding nature of this surgical maneuver which requires specialized instruments and advanced surgical skills [4, 5].
Concurrently, other studies and trials have yielded results suggesting that SILA achieves comparable outcomes to CLA and highlighting a lack of significant differences between the two techniques in numerous domains [6].
Given the ongoing debate and the diverse findings from individual studies, a comprehensive systematic review and meta-analysis is necessary to provide a clearer understanding of the relative benefits and risks of SILA compared to CLA in adult patients. This systematic review aims to synthesize existing evidence from randomized controlled trials (RCTs) to evaluate the efficacy, safety, and postoperative outcomes of SILA versus CLA, when they are performed by experienced surgeons.
Surgeon's experience is a confounding factor in surgical studies because it can significantly influence patient outcomes through variability in technique, the learning curve associated with new procedures, and better patient selection and postoperative management. Experienced surgeons may achieve lower complication rates and better overall results due to their skill and familiarity with specific techniques, which can skew comparisons between surgical methods if not properly controlled. Failure to account for a surgeon's experience can lead to misleading conclusions about the safety and effectiveness of surgical interventions. We have observed that former systematic reviews and meta-analysis do not account for surgeon’s experience as a confounder.
By consolidating data from multiple studies, this meta-analysis seeks to offer more definitive conclusions that can inform clinical decision-making and surgical practice. The results of this review will have significant implications for surgeons considering the adoption of SILA and for patients exploring minimally invasive options for appendectomy. Ultimately, this review aims to determine whether SILA offers similar outcomes to CLA, when performed by experienced surgeons.
WE adhered to the recommended guidelines of the Cochrane collaboration [7] as well as the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines [8] (supplementary Table 1). The methodology of this study was registered prospectively in PROSPERO with identification number CRD42024612596.
We performed an extensive and systematic literature search up to the 7th of November 2024. The eligibility criteria for this review followed the PICOTT format (population, intervention, control, outcomes, type of studies, time of follow-up). The population studied (P) were adult patients, 18 years old or older, with any indication for appendectomy, who underwent (I) SILA and were compared (C) against CLA. Surgeries were performed by experienced surgeons. The outcomes (O) assessed were the length of hospitalization, operative duration, postoperative complications, and surgical wound infections. This review focuses on therapeutic interventions of only RCTs, directly comparing the two approaches (T) and the time of follow-up (T) was unrestricted. Exclusion criteria included studies that did not fit the PICOTT question, did not report any outcomes, or did not directly compare the two techniques.
PubMed, Scopus, and Cochrane Library were used to retrieve relevant articles. The search term used was the (“Single-incision laparoscop*” OR “single-port laparoscop*” OR SILA) AND (“conventional laparoscop*” OR “standard laparoscop*” OR “multiport laparoscop*” OR “three-port laparoscop*”) AND (appendectomy OR appendicitis OR appendix OR “Appendicular abscess” OR “Appendicular mass” OR “Appendicular tumour” OR “complicated appendectomy” OR periappendiceal). At this stage of this review, we did not set any restrictions, i.e., age or surgeon’s experience. After we retrieved the studies, two authors (KK/OM) independently screened the titles and abstracts. The articles that were not excluded in title and abstract screening underwent full-text screening and were screened fully against the inclusion and exclusion criteria, by KK and OM, independently. Once the articles to be included in this review were identified, we cross-checked their reference list for any additional studies that could have been missed during the preliminary search. Conflicts were resolved by the supervisor (FG).
Two authors, KK/RK, independently, performed data extraction, using two pre-deisgned Excel tables. The first one included study and patient baseline characteristics, such as the author of the study, country, number of patients undergoing each procedure, total number of patients, age, severity of appendicitis, surgical technique, and follow-up. The second table included the outcomes of interest. If fewer than ten studies were included in the meta-analyses, it was agreed that both reviewers would independently extract data from each study, followed by cross-checking to prevent errors during data transfer. No assumptions or simplifications were made during the data extraction process, as all information was directly obtained from the published studies without contacting the authors.
To perform quality assessment of the included studies, we utilized the RoB 2 (Revised Cochrane risk-of-bias tool for randomized trials) at the study level. Quality assessment was performed by two reviewers (KK/RK) independently. For data analysis we utilized the odds ratios (OR), using the Mantel–Haenszel's formula, when the outcomes were dichotomous and the inverse variance mean differences when the outcomes were continuous. For both types of outcomes, we chose the random effects models as they consider the variability between studies as well as assume that the true effect sizes differ among the studies. Fixed-effects model was used as part of the sensitivity analysis. Moreover, a second sensitivity analysis (with excluding one study at the time-"leave one out") took place, to examine the extent that each study contributed to the observed variability. When studies reported their outcomes as median with ranges, they were converted to mean and standard deviation as described by Wan et al. [9]. Higgins I^2^ statistics was used to determine statistical heterogeneity, as described by the Cochrane Handbook [10]. Significant differences were considered when p value < 0.05. Funnel plots, to assess publication bias, were not utilized as we did not retrieve sufficient studies (10 or more). Cochrane Review Manager Tool (RevMan 5.4) software was used to conduct the meta-analysis [11].
A total of 373 articles were retrieved from three 163 from PubMed, 206 from Scopus, and 4 from the Cochrane Library. Using Rayyan Software, we manually identified and removed 144 duplicate records. This left 229 articles for title and abstract screening. Of these, 21 articles were selected for full-text review, and data were ultimately extracted from four studies. The screening process is illustrated in the PRISMA flowchart (Fig. 1).Fig. 1PRISMA flowchart
A total of 195 patients were studied by Teoh et al. [15] in Hong Kong, focusing on generalized peritonitis, while Kim et al. [13] included 98 patients in Korea with suppurative, gangrenous, or perforated appendicitis. Carter et al. [12] conducted their research in the USA with 75 patients, examining various severities of appendicitis, and Park et al. [14], also from Korea, studied 40 patients with perforated appendicitis. The surgical techniques varied, with Carter et al. [12] using a 12 mm umbilical incision and two 5 mm ports; Kim et al. [13] employing a 10 mm umbilical incision with two 5 mm trocars; Park et al. [14] utilizing two 5 mm trocars and one 10 mm trocar; and Teoh et al. [15] using two 5 mm ports. Follow-up periods ranged from 1 to 6 weeks across the studies (Table 1). Table 1Study characteristicsAuthorCountryNumber of patientsAgeSeverity of appendicitisSurgical techniqueFollow upSILACLATOTALCarter et al. [12]USA373875 > 23inflammation, mass, periappendicecal abscess, or diffuse peritonitisThe surgical approach involves a 12 mm umbilical incision for entry, supplemented by two 5 mm one in the left lower quadrant and another in the suprapubic midline. A linear stapler or looped suture is used as a cutting-and-sealing device during the procedure2–3 weeksKim et al. [13]Korea47519826–56Suppurative or gangrenous or perforates appendicitisa 10 mm umbilical incision and two additional 5 mm trocars in the left lower quadrant and suprapubic region. The appendix's base is ligated with Endoloops or an Endo-GIA stapler6 weeksPark et al. [14]Korea202040 > 25Perforated appendicitis or periappendiceal abscesstwo 5 mm trocars and one 10 mm trocar. An Endoloop is employed for closure, along with scalpels or endoclips for dissection and securing tissues1 weeksTeoh et al. [15]Hong Kong989719518–75Generalized peritonitis or abscess or abdominal masswo 5 mm ports placed in the left and right lower quadrants. An Endoloop is utilized for closure, alongside ultrasonic shears for dissection and tissue cutting14 daysSILA: single incision laparoscopic appendectomy, CLA: conventional laparoscopic appendectomy
The length of hospitalization for SILA ranged from approximately 1.4 to 3.53 days, while CLA ranged from 1.6 to 3.2 days. Operative durations for SILA were generally longer, with averages around 52–63.5 min compared to 38–63 min for CLA. Postoperative complications were observed in both groups, with SILA reporting between 2 and 14 complications and CLA reporting 4 and 9, indicating that SILA may have a higher complication rate in some studies. Surgical wound infections were low for both techniques, with SILA ranging from 0 to 8 infections and CLA from 0 to 5 (Table 2). Table 2Surgical outcomes of SILA vs CLAAuthorsLength of hospitalizationOperative durationPost-operative complication sSurgical wound infectionsSILACLASILACLASILACLASILACLACarter et al. [12]1.4 ± 0.81.6 ± 1.854 ± 1738 ± 125400Kim et al. [13]2.89 ± 1.562.71 ± 1.8952.2 ± 19.463 ± 213424Park et al. [14]N/aN/a63.5 ± 13.254 ± 12.52211Teoh et al. [15]3.53 ± 2.923.2 ± 2.3663 ± 27.260.2 ± 31.714985SILA: single incision laparoscopic appendectomy, CLA: conventional laparoscopic appendectomy
The assessment of studies using the ROB 2 tool reveals varying levels of risk of bias across the five domains (D1 to D5) for each author. Carter et al. [12] demonstrated low risk in all domains, indicating a robust study design and execution. Kim et al. [13] showed a potential concern in D2 regarding deviations from intended interventions, leading to an overall moderate risk of bias. Park et al. [14] had an unclear risk in D1, suggesting uncertainty in the randomization process, but overall maintained a moderate risk across other domains. Teoh et al. [15] scored favorably with low risk in all domains, reflecting strong methodological rigor. Overall, the findings indicate that while some studies exhibit strong risk management, others present potential weaknesses that could impact the validity of their conclusions (Table 3). Table 3Assessment of study quality using RoB 2In the ROB 2 (Risk of Bias 2) tool, D1 to D5 represent five key domains used to assess the risk of bias in randomized controlled trials. D1 evaluates the adequacy of the randomization process to prevent selection bias, ensuring that participants are allocated to intervention groups fairly. D2 examines whether participants received the intended interventions as assigned, assessing any deviations that may affect the outcomes. D3 focuses on the handling of missing outcome data, considering the impact of any missing information on the study’s conclusions. D4 looks at the measurement of outcomes, specifically whether outcome assessors were blinded to group allocations and if the methods used were reliable and consistent. Lastly, D5 assesses the risk of bias in the selection of reported results, ensuring that all pre-specified outcomes were reported transparently, without selective omission of unfavorable findings. Together, these domains provide a comprehensive framework for evaluating the overall risk of bias in a study
Length of hospitalization, operative duration, postoperative complications, and surgical wound infections were meta-analyzed (Fig. 2).Fig. 2Meta-analysis; A: length of hospitalization, B: operative duration, C: postoperative complications, D: surgical wound infections
Three studies with a total of 368 patients, 182 in SILA and 186 in CLA, investigated the length of hospitalization and showed a non-statistically significant difference between the two approaches [12, 13, 15]. WMD = 0.07 days [95%CI − 0.32, 0.47], I2 = 0%, p = 0.72.
Four studies with a total of 408 patients, 202 in SILA and 206 in CLA, investigated the operative duration and showed a non-statistically significant difference between the two approaches [12–15]. WMD = 4.49 min [95%CI − 7.02, 16.00], I2 = 89%, p = 0.44.
Four studies with a total of 408 patients, 202 in SILA and 206 in CLA, investigated the postoperative complications and showed a non-statistically significant difference between the two approaches [12–15]. OR = 1.32 [95%CI 0.69, 2.51], I2 = 0%, p = 0.40.
Four studies with a total of 408 patients, 202 in SILA and 206 in CLA, investigated the surgical wound infections and showed a non-statistically significant difference between the two approaches [12–15]. OR = 1 1.14 [95%CI 0.46, 2.83], I2 = 0%, p = 0.78.
We performed a sensitivity analysis by excluding one study at a time (“leave one out”) (Table 4) and one with fixed-effects models (Table 5). Table 4Sensitivity analysis by excluding each study for each outcomeStudy excludedWMD/OR [95%CI]I^2^p valueLength of hospitalizationCarter et al. [12]0.25 [ − 0.26, 0.75]00.33Kim et al. [13]0.03 [ − 0.49, 0.54]120.92Teoh et al. [15]−0.03 [ − 0.49, 0.44]00.91Operative DurationCarter et al. [12]0.49 [ − 11.34, 12.33]840.93Kim et al. [13]9.75 [2.14, 17.36]670.01Park et al. [14]2.78 [ − 12.99, 18.55]920.73Teoh et al. [15]5.00 [ − 10.76, 20.76]920.53Post-operative complicationsCarter et al. [12]1.32 [0.64, 2.71]00.46Kim et al. [13]1.46 [0.72, 2.96]00.29Park et al. [14]1.36 [0.69, 2.67]00.37Teoh et al. [15]1.05 [0.41, 2.65]00.92Surgical Wound infectionsKim et al. [13]1.53 [0.52, 4.45]00.44Park et al. [14]1.12 [0.39, 3.22]130.83Teoh et al. [15]0.62 [0.14, 2.76]00.53WMD: weighted mean difference, OR: odds ratio, CI confidence intervalTable 5Sensitivity analysis with Fixed effects modelOutcomeWMD/OR [95%CI]I^2^p valueLength of Hospitalization0.07 [ − 0.32, 0.47]00.72Operative Duration5.57 [1.74, 9.39]840.04Post-operative complications1.32 [0.70, 2.49]00.39Surgical ound infections1.13 [0.47, 2.73]00.79WMD: weighted mean difference, OR: odds ratio, CI confidence interval
The results were statistically significant with regard to operative duration when Kim et al.’s study was excluded [13], in the fixed-effect model.
In this systematic review and meta-analysis, we evaluated the outcomes associated with SILA compared to CLA. The findings revealed no significant differences in key postoperative metrics, including the length of hospitalization, operative duration, postoperative complications, and surgical wound infections between the two techniques. Notably, while SILA is often promoted for its potential cosmesis advantages, our results suggest that its efficacy and safety are comparable to those of CLA when performed by experienced surgeons. Previous studies have frequently included a heterogeneous patient population, encompassing both pediatric and adult patients, and often failed to account for critical factors such as age and the experience level of the surgeons involved. This oversight may contribute to variability in outcomes and limit the generalizability of the findings. By focusing exclusively on adult patients operated on by experienced surgeons, our study aimed to provide clearer insights into the relative benefits and risks of these surgical approaches, thereby addressing the existing literature gap.
Other studies have previously investigated the two approaches. In the study conducted by Duza et al. [16], which included patients over the age of 14 years, CLA was associated with shorter preoperative and intraoperative times compared to SILA, which showed reduced postoperative and reinsertion times. However, there were no significant differences in postoperative complications or cosmetic satisfaction between the two approaches. In comparison, our review found SILA and CLA produced similar outcomes in operative duration and complications, suggesting that the differences in timing noted by Duza et al. [16] may not be as pronounced in an adult population.
Golebiewski et al. [17] evaluated SILA against three-port laparoscopic appendectomy in a pediatric cohort, finding that although the operative time for three-port laparoscopic appendectomy was shorter, patients undergoing SPLA reported greater postoperative pain and increased levels of inflammatory markers, with no significant differences in hospital stay or complications. Our review indicated that SILA and CLA yielded comparable results regarding hospitalization length and postoperative complications, suggesting that the increased pain associated with SPLA in Golebiewski et al.'s study needs to be investigated in future adult populations [17].
In a diverse patient population aged 7–71 years, Kang et al. [18] reported a conversion rate of 11.1% to MPLS and found that SPLS was associated with longer recovery times and increased analgesic use. In contrast, our findings suggested that SILA and CLA had comparable outcomes in hospitalization length, operative duration, and complications, indicating that the higher recovery time noted in Kang et al.'s study may not be a consistent finding across different population groups [18].
Lee et al. [19] found no significant differences in overall complication rates or cosmetic satisfaction between SPLA and CLA in patients over 16 years, aligning with our results that suggest SILA and CLA yield similar outcomes concerning complications. In the study by Pan et al. [20], TSILA showed comparable operative times to the classic method and higher cosmetic satisfaction, but our review indicated that while SILA and CLA produced similar results, SILA’s advantages were less evident when factoring in the operational efficiency of CLA. However, the cosmesis effects needs to be further evaluated. The SCARLESS study group [21] reported that patients undergoing SPILS experienced better body image and cosmetic satisfaction, although it was technically more demanding. In contrast, our review highlighted that both SILA and CLA had similar outcomes, suggesting that while cosmetic benefits may be present with SILA in other studies, they did not translate into significant clinical differences when compared to CLA.
Lastly, Cirochi et al. [22] found that SILA had a longer operative time, but offered similar outcomes to CLA across all age groups. However, our review showed a non-significant difference in the operative duration. This consistency underscores the need for further research into postoperative pain and cosmetic outcomes, as our review indicated that both techniques are viable options for managing acute appendicitis without significant differences in clinical outcomes.
The findings from this systematic review and meta-analysis offer significant implications for health policymakers, healthcare providers, and patients regarding the management of acute appendicitis. For health policymakers, the comparable outcomes between SILA and CLA indicate that both techniques should be integrated into clinical guidelines, allowing flexibility in surgical approaches based on surgeon expertise and patient preferences. This could optimize resource allocation and improve overall surgical care. Surgeons are reminded of the critical role that experience plays in influencing surgical outcomes, as our study demonstrates that both techniques yield similar results in terms of hospitalization length, operative duration, and complications. This reinforces the notion that surgeons can confidently choose either approach based on their proficiency and the individual needs of patients, ultimately enhancing training programs that emphasize skill development in both methods. From the patient perspective, understanding that SILA and CLA are equally viable options can empower them to make informed decisions about their treatment. This knowledge may alleviate concerns associated with opting for a single-incision technique, particularly given its potential cosmetic advantages.
Surgeons adopting SILA and patients willing to undergo this type of surgery need to be aware of trocar-site hernia. A study by Antoniou et al. [23], which examined randomized clinical trials and compared their risk of trocar-site hernia between single-incision laparoscopic surgery (SILS) and conventional laparoscopic surgery, concluded that SILS had a significantly higher risk of trocar-site hernia compared to conventional laparoscopic surgery (odds ratio = 2.37, p = 0.008). Trial sequential analysis confirmed conclusive evidence of increased trocar-site hernia risk with SILS.
With the rise of minimally invasive surgery in general surgery [24–27], further research is essential to investigate patient-reported outcomes such as postoperative pain and satisfaction, as these factors significantly influence the overall patient experience and recovery trajectory. Understanding the nuances of postoperative pain levels between SILA and CLA will help clinicians better prepare patients for what to expect following surgery, ultimately leading to improved pain management strategies. Additionally, capturing patient satisfaction data can provide valuable insights into how different surgical approaches align with patient preferences and perceptions of care quality. These outcomes can be measured using standardized tools that assess not only the severity of pain, but also the patient's emotional and psychological well-being throughout the recovery period. Enhanced focus on these patient-reported outcomes can facilitate shared decision-making processes, allowing patients to engage actively in their treatment choices. By integrating findings from such research into clinical practice, healthcare providers can better tailor their approaches to align with individual patient values and preferences, fostering a more patient-centered care environment. Ultimately, a comprehensive understanding of postoperative experiences will contribute to improved surgical outcomes, heightened patient satisfaction, and more effective communication between patients and healthcare professionals, promoting an overall enhancement in the quality of surgical care for acute appendicitis.
This systematic review and meta-analysis has several limitations that should be acknowledged. First, the number of studies included in the analysis was limited, which may affect the generalizability of the findings. The studies analyzed had variability in their designs, surgical techniques, and definitions of outcomes, leading to potential heterogeneity in the data. The follow-up durations varied significantly among studies, potentially impacting the assessment of long-term complications and patient satisfaction. Furthermore, the studies included in the review did not extensively evaluate important factors such as postoperative pain and cosmesis, which are critical in assessing the overall success of surgical interventions. Finally, the exclusion of non-English language studies and unpublished data may have introduced publication bias, limiting the comprehensiveness of the evidence presented. Future research should aim to address these limitations by including a larger pool of studies with consistent methodologies and more rigorous reporting on surgeon experience and patient-reported outcomes.
In conclusion, this systematic review and meta-analysis provide valuable insights into the comparative effectiveness of single-incision laparoscopic appendectomy (SILA) versus conventional laparoscopic appendectomy (CLA) in adults, emphasizing the importance of surgeon experience in achieving optimal outcomes. Our findings demonstrate that both SILA and CLA yield similar results concerning length of hospitalization, operative duration, and rates of postoperative complications and surgical wound infections. This suggests that both techniques are viable options for managing acute appendicitis when performed by experienced surgeons. However, to enhance the decision-making process for both patients and healthcare providers, further research is warranted to explore patient-reported outcomes, such as postoperative pain and satisfaction, which are critical for understanding the overall impact of these surgical approaches on patient quality of life. By addressing these factors, we can improve shared decision-making processes and ensure that surgical interventions align with patient preferences and expectations. As surgical techniques continue to evolve, it is essential to integrate findings from ongoing research into clinical practice, ultimately enhancing the quality of care provided to patients undergoing appendectomy.
Below is the link to the electronic supplementary material.Supplementary file 1 (DOCX 35 KB)