Omental infarction (OI) is a rare condition with an overall incidence of less than 0.3%. It can occur spontaneously or can be secondary to trauma, surgery, and inflammation. While previously a diagnosis of exclusion, due to development in imaging technology, OI can now be identified based on CT findings. OI symptoms can mimic an acute abdomen, prompting potentially unnecessary surgical exploration. Treatment options range from conservative management to interventional radiology or surgical resection of the infarcted omentum. We are presenting the first case of OI following robotic-assisted inguinal hernia repair. This case highlights the importance of considering OI in differential diagnoses for patients presenting with acute abdominal pain, the utility of imaging workup in identifying OI, and guidance for conservative treatment approaches to reduce unnecessary surgical intervention.

BACKGROUND: Inguinal hernia repair lacks a standard repair technique, with laparo-endoscopic and open preperitoneal methods showing similar outcomes. Despite higher costs, the popularity of robotic surgery is on the rise, driven by technological advantages. Controversies persist in comparing open repair techniques with the robotic approach, given contradictory results. The objective of this study was to compare postoperative outcomes, including complications, chronic pain, and recurrence, between open and robotic-assisted preperitoneal inguinal hernia repair.
METHODS: This single-center retrospective study encompassed patients undergoing elective inguinal hernia repair in a specialized unit, employing both open preperitoneal and robotic-assisted laparoscopic approaches from September 2018 to May 2023. Comparative analysis of short- and long-term outcomes between these techniques was conducted. Additionally, multivariate logistic regression was employed to explore predictors of postoperative complications.
RESULTS: A total of 308 patients met the inclusion criteria. 198 (64%) patients underwent surgery using an open preperitoneal approach and 110 (36%) using robot-assisted laparoscopy. Patients in the robot-assisted group were younger (P = 0.006) and had fewer comorbidities (P < 0.001). There were no differences between the groups in terms of postoperative complications (P = 0.133), chronic pain (P = 0.463) or recurrence (P = 0.192). Multivariate analysis identified ASA ≥ III (OR, 1.763; 95%CI, 1.068-3.994; P = 0.027) and inguinoscrotal hernias (OR, 2.371, 95%CI, 1.407-3.944; P = 0.001) as risk factors of postoperative complications.
CONCLUSIONS: Both open preperitoneal and robotic-assisted laparoscopic approaches show similar outcomes for complications, chronic pain, and recurrence when performed by experienced surgeons. The open preperitoneal approach, with its quicker operative time, may be advantageous for high-comorbidity cases. Treatment choice should consider patient factors, surgeon experience, and healthcare resources.

BACKGROUND: We aimed to evaluate the safety and short-term outcomes of robotic-assisted transabdominal preperitoneal repair for inguinal hernia in 12 pioneering hospitals in Japan.
METHODS: Clinical data of patients who underwent robotic-assisted transabdominal preperitoneal repair between September 1, 2016, and December 31, 2021 were collected. Primary outcome measures were intra-operative adverse events and post-operative complications, whereas secondary outcomes were surgical outcomes, including chronic pain, recurrence, and learning curve.
RESULTS: In total, 307 patients were included. One case of inferior epigastric arterial injury was reported; no cases of bowel or bladder injury were reported. Thirty-five seromas were observed, including four (1.3%) cases that required aspiration. The median operative time of a unilateral case was 108 minutes (interquartile range: 89.8-125.5), and post-operative pain was rated 1 (interquartile range: 0-2) on the numerical rating scale. In complicated cases, such as recurrent inguinal hernias and robotic-assisted radical prostatectomy-associated hernias, dissection and suture were safely achieved, and no complications were observed, except for non-symptomatic seroma. All patients underwent robotic procedures, and there was no chronic post-operative inguinal pain, although one case of hernia recurrence was reported. Regarding the learning curve, plateau performance was achieved after 7-10 cases in terms of operative time (P < .001).
CONCLUSIONS: Robotic-assisted transabdominal preperitoneal repair can be safely introduced in Japan. Regardless of the involvement of many surgeons, the mastery of robotic techniques was achieved relatively quickly. The advantage of robotic technology such as wristed instruments may expand the application of minimally invasive hernia repair for complicated cases.

Surgical training requires clinical knowledge and technical skills to operate safely and optimize clinical outcomes. Technical skills are hard to measure. The Intuitive Data Recorder (IDR), (Sunnyvale, CA) allows for the measurement of technical skills using objective performance indicators (OPIs) from kinematic event data. Our goal was to determine whether OPIs improve with surgeon experience and whether they are correlated with clinical outcomes for robotic inguinal hernia repair (RIHR).
The IDR was used to record RIHRs from six surgeons. Data were obtained from 98 inguinal hernia repairs from February 2022 to February 2023. Patients were called on postoperative days 5-10 and asked to take the Carolina Comfort Scale (CCS) survey to evaluate acute clinical outcomes. A Pearson test was run to determine correlations between OPIs from the IDR with a surgeon\'s yearly RIHR experience and with CCS scores. Linear regression was then run for correlated OPIs.
Multiple OPIs were correlated with surgeon experience. Specifically, for the task of peritoneal flap exploration, we found that 23 OPIs were significantly correlated with surgeons\' 1-year RIHR case number. Total angular motion distance of the left arm instrument had a correlation of - 0.238 (95% CI - 0.417, - 0.042) for RIHR yearly case number. Total angular motion distance of right arm instrument was also negatively correlated with RIHR in 1 year with a correlation of - 0.242 (95% CI - 0.420, - 0.046). For clinical outcomes, wrist articulation of the surgeon\'s console positively correlated with acute sensation scores from the CCS with a correlation of 0.453 (95% CI 0.013, 0.746).
This study defines multiple OPIs that correlate with surgeon experience and with outcomes. Using this knowledge, surgical simulation platforms can be designed to teach patterns to surgical trainees that are associated with increased surgical experience and with improved postoperative outcomes.

This study aimed to compare perioperative outcomes of robotic and laparoscopic transabdominal peritoneal repair (TAPP) for unilateral inguinal hernia.
This single institutional retrospective cohort study used de-identified data of patients who underwent robotic TAPP (R-TAPP) or laparoscopic TAPP (L-TAPP) for unilateral inguinal hernia between January 1, 2016 and October 31, 2021. Two cohorts were propensity matched, and data were analyzed. The learning curve was evaluated in the R-TAPP group.
Among 938 patients analyzed, 704 were included. After propensity-score matching, 80 patients were included in each group. The difference in operative time between R-TAPP and L-TAPP groups was 10 min (99.5 and 89.5 min, p = 0.087); however, console/laparoscopic time was similar (67 and 66 min, p = 0.71). The dissection time for medial-type hernia in the R-TAPP group was marginally shorter than that in the L-TAPP group (17 and 27 min, p = 0.056); however, there was no difference for lateral-type hernia (38.5 and 40 min p = 0.37). Perioperative variables, including estimated blood loss, postoperative hospital stay, and postoperative pain, had no significant difference, and chronic pain, which needed medication or intervention, was not observed in each group. The number of cases needed to achieve plateau performance was 7-10 in the R-TAPP group.
This study suggests that R-TAPP was safely introduced, and its perioperative outcomes were not inferior to those of L-TAPP. A shorter dissection time for medial-type hernia might be due to the robot\'s advantages, and a fast-learning curve could help with the early standardization of the procedure.

To compare clinical outcomes for open, laparoscopic, and robotic hernia repairs for direct, unilateral inguinal hernia repairs, with particular focus on 30-day morbidity surgical site infection (SSI); surgical site occurrence (SSO); SSI/SSO requiring procedural interventions (SSOPI), reoperation, and recurrence.
The Abdominal Core Health Quality Collaborative database was queried for patients undergoing elective, primary, > 3 cm medial, unilateral inguinal hernia repairs with an open (Lichtenstein), laparoscopic, or robotic operative approach. Preoperative demographics and patient characteristics, operative techniques, and outcomes were studied. A 1-to-1 propensity score matching algorithm was used for each operative approach pair to reduce selection bias.
There were 848 operations included: 297 were open, 285 laparoscopic, and 266 robotic hernia repairs. There was no evidence of a difference in primary endpoints at 30 days including SSI, SSO, SSI/SSO requiring procedural interventions (SSOPI), reoperation, readmission, or recurrence for any of the operative approach pairs (open vs. robotic, open vs. laparoscopic, robotic vs. laparoscopic). For the open vs. laparoscopic groups, QoL score at 30 day was lower (better) for laparoscopic surgery compared to open surgery (OR 0.53 [0.31, 0.92], p = 0.03), but this difference did not hold at the 1-year survey (OR 1.37 [0.48, 3.92], p = 0.55). Similarly, patients who underwent robotic repair were more likely to have a higher (worse) 30-day QoL score (OR 2.01 [1.18, 3.42], p = 0.01), but no evidence of a difference at 1 year (OR 0.83 [0.3, 2.26] p = 0.71).
Our study did not reveal significant post-operative outcomes between open, laparoscopic, and robotic approaches for large medial inguinal hernias. Surgeons should continue to tailor operative approach based on patient needs and their own surgical expertise.

Concomitant robotic-assisted laparoscopic prostatectomy (RALP) and robotic inguinal hernia repair (RIHR) has been reported. Nevertheless, data on its safety is lacking and some surgeons avoid performing both operations concurrently due to the potential risk of mesh related complications in the setting of a fresh vesicourethral anastomosis. We aimed to investigate differences in 30-day outcomes between patients undergoing RALP+RIHR and those undergoing RIHR alone.
Patients who have undergone concomitant RALP and RIHR with 30-day follow-up available were identified within the Abdominal Core Health Quality Collaborative. Using a propensity score algorithm, they were matched with a cohort of patients undergoing RIHR alone based on confounders such as body mass index, age, ASA class, smoking, hernia size and recurrent status and prior pelvic operation. The groups were compared for 30-day rates of surgical site infection (SSI), surgical site occurrences (SSO), surgical site occurrences requiring operative intervention (SSOPI) and hernia recurrence.
24 patients underwent RALP + RIHR and were matched to 72 patients who underwent RIHR alone (3:1). Median age was 64 years, 33% were obese and 17% smokers. No significant differences were found on 30-day rates of overall complications (21% RALP + RIHR vs. 15% RIHR, p = 0.53) and surgical site occurrences (12% RALP + RIHR vs.11% RIHR, p = 0.85). No patient in the RALP + RIHR group had a 30-day SSI, SSOPI or early recurrence.
RALP+RIHR appears not to result in increased rates of wound complications, overall complications or early recurrence when compared to patient undergoing RIHR alone. Prospective, controlled studies with larger number of patients are needed to confirm our findings.

Robotic inguinal hernia repair is growing in popularity among general surgeons despite little high-quality evidence supporting short- or long-term advantages over traditional laparoscopic inguinal hernia repair. The original RIVAL trial showed increased operative time, cost, and surgeon frustration for the robotic approach without advantages over laparoscopy. Here we report the 1- and 2-year outcomes of the trial.
This is a multi-center, patient-blinded, randomized clinical study conducted at six sites from 2016 to 2019, comparing laparoscopic versus robotic transabdominal preperitoneal (TAPP) inguinal hernia repair with follow-up at 1 and 2 years. Outcomes include pain (visual analog scale), neuropathic pain (Leeds assessment of neuropathic symptoms and signs pain scale), wound morbidity, composite hernia recurrence (patient-reported and clinical exam), health-related quality of life (36-item short-form health survey), and physical activity (physical activity assessment tool).
Early trial participation included 102 patients; 83 (81%) completed 1-year follow-up (45 laparoscopic vs. 38 robotic) and 77 (75%) completed 2-year follow-up (43 laparoscopic vs. 34 robotic). At 1 and 2 years, pain was similar for both groups. No patients in either treatment arm experienced neuropathic pain. Health-related quality of life and physical activity were similar for both groups at 1 and 2 years. No long-term wound morbidity was seen for either repair type. At 2 years, there was no difference in hernia recurrence (1 laparoscopic vs. 1 robotic; P = 1.0).
Laparoscopic and robotic inguinal hernia repairs have similar long-term outcomes when performed by surgeons with experience in minimally invasive inguinal hernia repairs.

Black patients and older adults are less likely to receive minimally invasive hernia repair. These differences by race and age may be influenced by surgeon-specific utilization rate of minimally invasive repair. In this study, we explored the association between race, age, and surgeon utilization of minimally invasive surgery (MIS) with the likelihood of receiving MIS inguinal hernia repair.
A retrospective cohort study was performed in patients undergoing elective primary inguinal hernia repair from 2012 to 2016, using data from the Michigan Surgical Quality Collaborative, a 72-hospital clinical registry. Surgeons were stratified by proportion of MIS performed. Using hierarchical logistic regression models, we investigated the association between receiving MIS repair and race, age, and surgeon MIS utilization rate.
Out of 4667 patients, 1253 (27%) received MIS repair. Out of 190 surgeons, 81 (43%) performed only open repair. Controlling for surgeon MIS utilization, race was not associated with MIS receipt (OR 0.93, p = 0.775), but older patients were less likely to receive MIS repair (OR 0.41, p < 0.001).
Race differences were explained by surgeon MIS utilization, implicating access to MIS-performing surgeon as a mediator. Conversely, age disparity was independent of MIS utilization, even after adjusting for comorbidities, indicating some degree of provider bias against performing MIS repair in older patients. Interventions to address disparities should include systematic efforts to improve access, as well as provider and patient education for older adults.

MIS utilization for inguinal hernia repair is low compared to in other procedures. The impact of low adoption in surgeons is unclear, but may affect regional access to minimally invasive surgery (MIS). We explored the impact of surgeon MIS utilization in inguinal hernia repair across a statewide population.
We analyzed 6723 patients undergoing elective inguinal hernia repair from 2012 to 2016 in the Michigan Surgical Quality Collaborative. The primary outcome was surgeon MIS utilization. The geographic distribution of high MIS-utilizing surgeons was compared across Hospital Referral Regions using Pearson\'s Chi-squared test. Hierarchical logistic regression was used to identify patient and hospital factors associated with MIS utilization.
Surgeon MIS utilization varied, with 58% of 540 surgeons performing no MIS repair. For the remaining surgeons, MIS utilization was bimodally distributed. High-utilization surgeons were unevenly distributed across region, with corresponding differences in regional MIS rate ranging from 10 to 48% (p < 0.001). MIS was used in 41% of bilateral and 38% of recurrent hernia. MIS repair was more likely with higher hospital volume and less likely for patients aged 65+ (OR 0.68, p = 0.003), black patients (OR 0.75, p = 0.045), patients with COPD (OR 0.57, p < 0.001), and patients in ASA class > 3 (OR 0.79 p < 0.001).
MIS utilization varies between surgeons, likely driving differences in regional MIS rates and leading to guideline-discordant care for patients with bilateral or recurrent hernia. Interventions to reduce this practice gap could include training programs in MIS repair, or regionalization of care to improve MIS access.