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Surgical Anatomy and Intrapelvic Course of Obturator Nerve
Merve Didem Eşkin Tanrıverdi1, Ayhan Cömert2, Zekiye Gözde Kara3
1Department of Gynecology and Obstetrics, Ankara Bilkent City Hospital (Dr. Eşkin Tanrıverdi), Ankara, Turkey.
Study Objective:
The aim of this study is to reveal the anatomy of the obturator nerve (ON) and its important relationship in pelvic surgery with the surrounding anatomical structures.
Design:
Prospective observational study.
Interventions:
Parameters from the left and right ON's to relevant anatomical landmarks were measured and statistical analysis was performed.
Setting:
The current study was planned in Department of Anatomy Ankara University School of Medicine and then conducted at the Forensic Medicine Institute, Ankara Group Presidency after receiving the approval of the Institute for Forensic Medicine.
Participants:
The study was performed in 40 fresh or fresh-frozen and female cadavers bilaterally.
Measurements And Main Results:
The mean distances of the midpoint of the left ON to the highest point of the fundus of uterus and isthmus of the uterus, cervico-uterine junction, and highest point of the promontory were 55.1 ± 10.4, 52.9 ± 12.4, 54.8 ± 11.3, and 58.5 ± 15.2 mm, respectively, and 58.7 ± 8.1, 52.5 ± 13.1, 61.4 ± 17.8, and 62.2 ± 19.7 mm on the right side, respectively (p > .05 for all values). The mean distance between the nerve root of the left ON and highest point of the promontory was 59.1 ± 28.4 mm, it was 59.7 ± 26.2 mm on the right side (p > .05). There were significant positive correlations between the distance between the left and right anterior superior iliac spines and the distances between the midpoint of the ON to the isthmus of the uterus on both the left and right sides of the pelvis (r = 0.546, p = .019, r = 0.896, p < .001, respectively).
Conclusions:
Intraoperative ON injury in gynecological procedures is a complication that may be minimized with good anatomical knowledge. Careful dissection should be performed to decrease the ON injury. The safe surgical zone was established for pelvic procedures by creating a topographical map of the ON. This research may improve pelvic surgery precision, aiding the development of better treatments and reducing ON-related complications.
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