A systematic search of OVID, Medline, PubMed, EMBASE, and Cochrane reviews was performed on 4th January 2023. Papers included were read in full and reference sections interrogated to identify any more papers which could potentially have been missed from the search.

The following search strategy was used.

((Femoral hernia) AND (laparoscop* OR minimal access OR robotic)) AND (strangulat* OR obstruct* OR incarcerat*).

Results returned from each search are shown in the PRISMA diagram in Figure 1.

OVID Medline 94, OVID Embase 206, Pubmed 167, Duplicates 181, Cochrane database 0.

286 unique papers were identified. Papers were screened by title and abstract prior to inclusion or exclusion. After abstract screening there were 87 articles potentially eligible. These articles were reviewed in full to assess for eligibility for inclusion. After review of the papers 5 further papers were identified from the reference sections.

24 case reports, and 9 papers were identified.

Case reports were summarised and tabulated extracting data for the characteristics as shown in Table 1. Case series and cohorts studies were summarised in Table 2.

24 case reports were identified as outlined in Table 1. Data has been included when stated in the case report. Reports are more common recently but they range from 2008 to 2022. There were older case reports than this, but we were unable to retrieve the full papers. The most common country reporting cases was the UK with 5 (21%) of reports. There was a female to male ratio of 22:2, and hernias were much more likely to be right sided at 21:3. Median age was 71.5 (range 35–94).

The most common procedure was a laparoscopic appendicectomy due to De Garengeot’s hernia with a mixture of hernia repairs via an open, or minimal access approach. There were no cases managed robotically reported. There will be an element of reporting bias as this would be a relatively unusual finding and more likely to be reported.

None of the case reports indicate why they chose a laparoscopic approach in particular and there was no randomisation.

There were no significant complications and the length of stay was usually short, with most patients being discharged on day 1–2. The longer lengths of stay were associated with hernias containing small bowel. None of the cases reported any conversions to open surgery.

Clyde et al. (2018) reported a retrospective review of 297 consecutive cases prospectively collected, of primary femoral hernia repairs, between 2007 and 2013. Patients who were uncontactable were excluded, leaving 138 patients included in the study. Their primary outcome was recurrence, particularly looking at the role mesh played. This was defined as an ipsilateral groin swelling confirmed at outpatient follow up, or on patient reported symptoms during a telephone interview as part of the audit. Telephoned patients were then reviewed in person, and recurrence confirmed clinically in 80% of cases. Repairs were categorised as low (Lockwood) approach, high (McEvedy approach) or TEP, no TAPP repairs were performed. TEP repairs were performed without mesh fixation. They presented data for both elective and emergency cases. Within the 138 patients included, 45 were operated on as an emergency, and 47 by TEP. It is not possible to discern what proportion of the TEP cases were operated on electively as the emergency and electively data was not separated by approach. Mesh was used in only 6 emergency cases, but was used in all 47 TEP repairs, implying that there were few emergency TEP repairs, and the vast majority were elective. Their primary outcome of recurrence showed no significant difference in recurrence rates between the various operation techniques, use of mesh or primary sutured repair, or between patients operated on electively or as emergency. There was no indication as to why an open or laparoscopic approach was chosen, and no randomisation. The follow up was relatively long as few studies in femoral hernias have a 5 years follow up (38).

Rebuffat et al. (2005) presented prospective data on strangulated groin hernias having reviewed a prospectively collected database of 1532 consecutive TAPP hernia repairs. There were 28 emergency cases, of which 7 were femoral hernias. There were no major “complications” with one patient having a haematoma. Mean length of stay was 3.9 days (0–38) and small bowel resection was required in 7 cases. Mean follow up was 340 days with no recurrences noted in the follow up period. There were 3 conversions (10.7%) 1 because of extensive adhesions, 2 because of a lack of space due to intestinal distension, it is unclear if these were femoral or inguinal hernias. Data for the outcomes of the emergency repairs is not presented separately for femoral and inguinal hernias so again, no significant conclusions can be drawn relevant to femoral hernias particularly other than they did not appear to have any major differences in outcomes compared with the inguinal hernias (39).

Chihara et al. (2018) reported prospectively collected data for 106 patients with incarcerated groin hernias, 30 femoral, of which 17 had open operations, and 13 laparoscopic. The study period was between 2000 and 2017, adopting a laparoscopic approach for the second half of the study period, and the two arms did not run concurrently. The two groups were comparable with no statistically significant difference in age, sex, BMI, ASA or hernia type. They compared open and laparoscopic cases and presented data without specifying the hernia type. Whilst their data does not pertain only to femoral hernias there were some interesting conclusions. They showed a significant reduction in post operative complications in the laparoscopic cohort (18.%/3.9% p = 0.172), with 2 bladder injuries in the open group. They do not report the experience or grade of the surgeons associated with these particular cases. There was 1 conversion in the laparoscopic (TAPP) group due to a large inguinoscrotal hernia being unmanageable laparoscopically. They also recommended a 2 stage approach in the presence of perforation or pus, with laparoscopic sutured hernia repair, and a delayed mesh repair at a later date. This was performed in 7 patients with no significant complications. The length of stay in the laparoscopic group was shorter (5.6 vs. 14.7 days). There will have been many changes in medical practice during the 17 years of the study and there any many potential sources of bias around their management (40).

Most of the data presented in these studies is not presented separately either for femoral and inguinal hernias, or elective and emergency case, and therefore unfortunately only limited conclusions regarding femoral hernias specifically can be made, and a meta-analysis cannot be performed. They appear to show no major differences in outcomes between femoral and inguinal hernias, but the numbers are low and would be underpowered unless differences in outcomes were large.

Within the 24 case reports there was significant variation in the role laparoscopy played. In 15 of the cases the repair was performed via a laparoscopic technique, 9 TAPP, 3 TEP, 3 sutured with 1 sutured and then an open plug repair. There was also a significant role played in the management of the hernia sac contents, primarily in the treatment of appendicitis, but also small bowel resection. The important diagnostic role of an MIS approach, allowing sac contents to be examined without the need for lower midline laparotomy should be appreciated. 6 out of 24 cases included resection of sac contents laparoscopically. Presumably this would have been more difficult in most of these cases through a groin incision. There will be an element of selection bias simply because a case is more likely to be reported if it is interesting and unusual, and therefore simple hernia repairs are less like to be reported.

Within the reported cohort studies and case series there is a low conversion rate, with few intra operative complications. There was no statistically significant difference between the conversion rates of elective and emergency cohorts in any of the papers suggesting that a laparoscopic approach is feasible and technically achievable.

There is little evidence to support TEP or TAPP over one another. Several of the case reports discussed the benefit of TEP for obstructed small bowel hernias, where they found that there was more space in the extraperitoneal plane. In these cases, they examined the hernial contents via traditional laparoscopy, and converted to TEP for the mesh placement. Both conversions in Rebuffat’s (39) case series were because of a lack of space, attempting TAPP repair of an obstructed small bowel hernia. Logically this approach should reduce mesh infection by separating the mesh from potentially infected sites, but there is no evidence to support this. In the author’s opinion it is harder to assess the viability of hernia contents adequately via a TEP approach. The larger registry studies do not report on conversion rates. The author’s can tentatively suggest that in the presence of small bowel obstruction and dilated bowel that a TEP repair may be more easily achievable. Logic would suggest a reduced rate of small bowel injury if the peritoneal cavity is not entered, but there is no evidence to support this statement.

Dahlstrand (41) was unable to demonstrate a significant advantage for any technique in the emergency setting implying that laparoscopic repair is at least non-inferior to open sutured repair in terms of recurrence alone, although numbers were low and may well be underpowered except for large differences. The number of laparoscopic cases in the emergency cohorts in all the papers were low, a re-examination of the Swedish and Danish Hernia registers, specifically looking at the emergency cases, would likely find many more cases now with a further 10–15 years of practice.

There was no significant evidence presented regarding long term chronic pain or quality of life assessment. Within the setting of emergency femoral hernia repairs this raises the question of the requirement for mesh, given there is no demonstrable reduction in recurrence rate, and the current political climate around mesh and mesh complications. There was no evidence of an increased mesh infection rate in any of the papers or case reports when compared with elective cases to suggest it should be avoided in the emergency setting. Mesh has previously been shown to be safe in the emergency management of inguinal hernias (42) and logically this could be extrapolated to femoral hernias if a benefit of mesh use was demonstrated.

Within the case reports the median length of stay was not stated in 4/24 cases, and only stated as “soon” in another. The median length of stay in the others was 2 (range 1–10) None of the case series differentiated data adequately to find the length of stay for emergency laparoscopic femoral hernia repairs. It appears that the length of stay in patients operated on laparoscopically is at least as good as that via an open approach. The case series and cohort studies presented the data without discriminating adequately as to allow comment on the length of stay in emergency MIS cases in particular, although where stated length of stay was lower in the MIS cohorts. The benefits of MIS have been established elsewhere in regards to length of stay and return to normal function.

There were no increased complication rates associated with laparoscopic surgery in any of the large series. Chihara (40) found a statistically significantly lower complication rate in the laparoscopic cohort, but this was a small series and could be skewed by the two complications (bladder injury) in the open cohort. There is no evidence to suggest that laparoscopic management is unsafe. There are no comments in any of the papers regarding surgical site infections or long-term complications such as adhesions or port site hernias.

None of the eligible papers or case reports included any assessment of quality of life, or return to normal function, but they mostly included a length of stay which was usually quite short. There is no new data presented in the case series or the Hernia registry papers. However, there are no major complications or problems on follow up, suggesting that the benefits of MIS should still pertain to an emergency cohort as established already in the elective setting, combined with an avoidance of laparotomy where assessment of the hernia contents is required.