A South Indian cadaveric study on obturator neurovascular bundle with a special emphasis on high prevalence of 'venous corona mortis'.

Surgical procedures in the pelvic region are very challenging because of the complex anatomy of this region. "Corona mortis" is a term used to describe retro-pubic anastomosis between the obturator and external iliac vessels. It is considered as a key structure as significant haemorrhage may occur if the vessels are cut accidentally during pelvic surgeries. Earlier studies have documented a high frequency of venous anastomosis compared to its arterial counterpart. The objective of our study was to document the prevalence of venous corona mortis in South Indian human adult cadaveric pelvises. We conducted this study on 73 cadaveric pelvic halves. Out of the 73 hemi pelvises, 36 were normal without any variations of the obturator vessels while 37 hemi pelvises (51%) showed the presence of abnormal obturator vessels which proves to be a very high incidence in terms of variations. Out of the 37 hemi pelvises, 25 (68%) showed the presence of 2 obturator veins, out of which 1 was normal and the other was an abnormal obturator vein. 8 hemi pelvises (22%) had only abnormal obturator vein. Most of the abnormal obturator veins drained into the external iliac vein, while two veins drained into inferior epigastric veins. Venous corona mortis is said to be frequently encountered during surgery and is considered to be as important as arterial corona mortis in its clinical implications. Individual evaluation of this risky anatomical structure should be done prior to any surgical interventions.

Accessory obturator nerves with bilateral pseudoganglia in man.

During the routine dissection of the pelvis and anterior thigh of an adult female cadaver, accessory obturator nerves were found bilaterally with pseudoganglia. In addition, each accessory obturator nerve rejoined the anterior division of the normally placed obturator nerves after traveling superficial to the pubic bones. Histological sections revealed primarily normal nerve with no neuronal cell bodies within these focal areas of enlargement. No inflammatory response was noted in these histologically normal peripheral nerve structures. Further gross anatomy including other peripheral nerves was found to be normal. Peripheral nerve "ganglia" are found in the literature with little focus on histology. Our case report represents to our knowledge, the first report of a pseudoganglion in association with an accessory obturator nerve.