The obturator externus muscle was carefully removed from its origin and the contents of the obturator canal were dissected out.
The obturator externus muscle is the deepest muscle of the superomedial part of the thigh.
The superior free edges of the obturator internus muscle and its fascia, the obturator membrane (between the anterior and posterior obturator tubercles), and the obturator externus muscle and its fascia collectively form the musculotendinous aponeurotic arch which converts the obturator groove into an obturator canal.
The contents of the obturator canal include: i) superomedially, nerve to obturator externus muscle, and obturator artery, ii) inferomedially, obturator vein, and iii) superolaterally, anterior and posterior divisions of the obturator nerve, which lay within the obturator groove.
Within the obturator canal, the posterior division of the obturator nerve is bound superiorly by the anterior division of the nerve, and inferiorly by the obturator artery and the nerve to obturator externus muscle.
In the current anatomic study, it was found that in most cases, prior to entering the obturator canal, the obturator nerve gave off branches to the obturator artery, periosteal nerve branches and the nerve to obturator externus muscle, and then divided into the anterior and posterior divisions.
In 32 lower limbs, the posterior and anterior divisions of the obturator nerve emerged into the thigh anterior to the obturator externus muscle and its fascia, accompanied by the branches of the obturator artery and vein (Figure 2).
In 22 lower limbs, the posterior division of the obturator nerve, after exiting the canal, descended posterior to the proximal quarter of the obturator externus muscle and its fascia.