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The Pudendal Nerve and Its Branches in Relation to Richter's Procedure
Sonè van der Walt1, Anna Catherina Oettlé, Frans Jacob van Wijk
1Department of Anatomy, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, South Africa.
Objective:
Variations in the branching pattern of the pudendal nerve (PN) have been described in the literature. This study investigated these variations in order to comment on a safe area for the placement of a Richter's stitch.
Methods:
Richter's procedure was performed on nine unembalmed female cadavers and followed by dissection. PN dissections were done on another 20 embalmed female cadavers. Variations in the branching pattern of the PN were noted and the distance between the Richter's stitch placed and the PN/or the inferior rectal nerve (IRN) measured.
Results:
The IRN entered the gluteal region as a separate structure in 6/29 cases. The separate IRN was found to pass between 4.1 and 14.45 mm medial to the ischial spine in 18/29 cases. In one case, the Richter's stitch was found to pierce the IRN. The distance between the stitch and the PN and/or the IRN ranged from 0 to 17.8 mm.
Conclusions:
To minimize the risk of nerve damage or entrapment, the Richter's stitch should be placed >20 mm from the ischial spine. This recommended area should be revised for different population groups, as variations might exist between groups.
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