BLH is a rare female-specific internal hernia that accounts for 4% to 5% of all internal hernias [1]. There has been an increase in the number of BLH cases reported in Japan [2, 4,5,6,7]. This trend may be associated with the advanced aging of the Japanese population, or could be explained by publication bias because most of the reports from Japan were related to laparoscopic surgery. Despite it being an intriguing issue, it remains unclear whether racial difference exists or not because precise data on the incidence of BLH are unavailable as yet.
To know whether recurrence cases of BLH have been reported or not, we searched the literature using PubMed database, selecting “broad ligament,” “hernia,” and “recurrence” as key words. Although we were able to get two hits, careful examination revealed that neither reported recurrence cases. Then, we searched the Japana Centra Revuo Medicina database in a similar manner and found one report of a recurrence case of BLH by Aisu et al. [2] in Japanese. In that case, a 49-year-old woman who had a history of left BLH two years before underwent laparoscopic surgery for the repair of ipsilateral BLH. They reported that the defect in the broad ligament was closed using absorbable suture in the first surgery.
Two classifications are used for diagnosing BLH on the basis of the nature and the location of the defect. Hunt classified BLH into two types: fenestra and pouch, based on the nature of the defect [8]. The most common fenestra type is characterized by a complete two-layer defect of the broad ligament. The pouch type is a hernia forming a pouch caused by a one-layer defect or an attenuation of the mesometrium. Cilley’s classification is anatomically based and includes three types [9]. In type 1, the defect develops caudal to the round ligament of the uterus. In type 2, the defect is located above the round ligament between the mesovarium and the mesosalpinx, and in type 3, the defect occurs in the mesoligamentum teres of the uterus. We summarize those two classifications in a figure (Fig. 4). Our present case was classified as fenestra type and type 1, respectively.
As regards the mechanisms of the defect formation, two hypotheses are raised: congenital and acquired. A defect in the broad ligament of the uterus was observed in 0.5% of autopsy cases [10]. Rose [11] reported BLH in a 16-year-old girl, which could be important evidence that defects in the broad ligament are congenital at least in some BLH cases. On the other hand, Slezak et al. [12] pointed out that more than 85% of BLH cases occurred in parous women, suggesting that the decreased elasticity of the broad ligament associated with pregnancy or injury at delivery is relevant to the defect formation. The patient in the present case had a history of two deliveries. Furthermore, the fact that recurrence cases exist may support the hypothesis that the defects of BLH are acquired.
Diagnosing BLH was difficult prior to the prevalence of CT. Routine examinations including abdominal X-ray and laboratory tests yielded no abnormal findings in the present case. Contrast-enhanced CT is considered essential for the diagnosis of BLH [13]. BLH has the following characteristics: (1) a dilated small-bowel loop in the vicinity of the pouch of Douglas or uterus; (2) a shifted or compressed uterus, sigmoid colon, or rectum as a result of the small-bowel loop; and (3) congested mesentery converging at the broad ligament, which is associated with the small-bowel loop [14]. All these characteristics were noted in the present case, which prompted our decision for early intervention and resulted in successful bowel rescue. BLH has a high risk of strangulation and requires surgery for the reduction of herniated bowels. Clinicians should be aware of the above-mentioned characteristics when reading CT images of patients with acute abdomen, particularly in middle-aged parous patients.
Because of the rarity of BLH, a standard procedure for BLH repair has yet to be determined. As defects in the mesometrium are small in size, simple closure is generally selected [4,5,6,7, 13,14,15]. From their experience of the recurrence case, Aisu et al. [2]. proposed the use of non-absorbable strings for closure of a defect in the broad ligaments or a wide opening with incision of the fallopian tube and the round ligament as a more secure alternative than simple closure because BLH patients are presumed to have congenital weak mesometrium. Despite the lack of description of the strings used, we surmised that absorbable suture was used in the first surgery for BLH, given that the hospital routinely selected absorbable suture, and two-layer closure with non-absorbable suture was used to repair the mesometrial defect.
