Obturator hernia is a rare type of abdominal hernia. Its pathogenesis is attributed to the loss of preperitoneal fat and lymphatic tissues, which normally overlie the obturator canal, thus creating a space around obturator vessels and nerves . Concomitant illnesses, such as chronic obstructive pulmonary disease, constipation, and kyphoscoliosis could result in increased intraperitoneal pressure and facilitate the growth of the hernia sac . Lean and elderly women are usually affected as they have less preperitoneal fat and several comorbidities, which favor the pathogenesis of this condition.
Laparotomy is the standard approach for the treatment of obturator hernia, since preoperative diagnosis is difficult owing to its rarity and non-specific signs and symptoms. Ziegler et al. have mentioned that “Obturator hernia needs a laparotomy, not a diagnosis” . Likewise, many surgeons believe that emergency laparotomy is the most optimal treatment for possible incarcerated obturator hernias. However, recent advances in imaging techniques, such as computed tomography and ultrasonography, have improved the rate of correct preoperative diagnosis, which has made less invasive approaches feasible to undertake [2–4]. Few studies have described less invasive therapeutic strategies, such as elective surgeries following successful manual reduction [5–7]. Elective surgeries were shown to be associated with a higher rate of TAPP implementation. The reason for undertaking laparoscopic approaches less frequently in emergency surgeries could be attributed to the smaller peritoneal cavity resulting from a dilated intestine.
This study aimed to evaluate the efficacy of FROGS as the first choice of treatment for incarcerated obturator hernias. Usually, patients with obturator hernia have comorbidities, which makes them unsuitable for emergency surgeries. They should be treated with less invasive therapy in an elective setting, if possible. In addition, it is often the case that some patients and their families do not consent to surgery. Ceresoli et al. showed that emergency surgery for complicated inguinal hernias is burdened by high morbidity and mortality rates in elderly patients . For patients with asymptomatic or minimally symptomatic inguinal hernias, watchful waiting is recognized as an acceptable option [15, 16]. Although these studies have mainly focused on inguinal hernias, the results could apply to obturator hernias as well.
In our study, emergency surgeries could be avoided in asymptomatic or minimally symptomatic patients because of the implementation of FROGS. Some of these patients underwent safe elective TAPP repair, while in others, comorbidities or family wishes were decisive factors. Irrespective of whether elective surgery was performed or not, bowel resection could be avoided in all patients. In addition, the short-term prognosis between the after-FROGS and before-FROGS groups was comparable. Although the balance between the risks of elective surgery versus the risks of a watchful approach is still a matter of debate in the absence of specific recommendations for elderly patients , a watchful approach could be a choice based on this result and the literature.
Although patients who do not undergo elective surgery are still at risk of recurrence, FROGS can be reproducible in cases of recurrence owing to its high success rate. Therefore, we believe that FROGS can be the first choice of treatment in any case of obturator hernia incarceration. The mechanism of FROGS is unclear and may be complex. However, we believe that complex coordinated movements of muscles around the obturator canal may have an important role. The driving pressure generated by these movements helps surgeons to reduce the hernia sac. In addition, at some point during this maneuver, the obturator canal may be maximally relaxed (usually in Step 3, based on our experience), and by repeating FROGS, we can eventually find this particular point.
The necessity of bowel resection is hard to decide, especially if FROGS is implemented. No patients in the after-FROGS group required bowel resection. The longest duration from symptom onset to hernia presentation was 72 hours. Based on this result, we can argue that if there is no obvious evidence of strangulation or ischemia, a manual reduction by FROGS is acceptable within 72 hours.
The limitation of this study is the relatively small sample size. Further observations and analyses are necessary to confirm the effectiveness of FROGS. Notwithstanding these limitations, manual reduction with FROGS was found to be safe and reproducible and can be the first treatment choice for obturator hernia. FROGS can be used instead of emergency surgery as a less invasive method to treat patients with obturator hernia while preserving the bowel.