Obturator hernia
Anatomy/pathophysiology
[edit | edit source]- Obturator canal - 1cm wide, 2-3cm long tunnel between obturator externus and internus muscles
- Obturator foramen - space between pubic rami and ischial bones, covered by obturator membrane in all but anterior superior aspect
- Obturator nerve, artery and vein travel through the canal. Nerve divides into anterior and posterior branches within the canal
- Obturator hernia is a protrusion through the obturator canal and foramen
- Develops through a widening defect of the obturator externus and internus muscles, coursing along either anterior or posterior branch of nerve
- Symptoms occur more commonly with compression of anterior branch
Presentation
[edit | edit source]- Rare but high-risk - gangrenous bowel seen in up to half of repairs
- Female to males of 6:1 - larger and more oblique incline of the obturator canal in the female pelvis
- More common on right - left side protected by sigmoid colon
- Typical patient is an emaciated elderly woman with intermittent bowel obstruction and weight loss
- Usual hernia risk factors and multiparity
- Howship-Romberg sign: referred pain down the medial thigh to the knee through compression of the obturator nerve with extension, abduction and medial rotation that is relieved by flexion of the thigh
- CT is best
Management
[edit | edit source]- Require rapid surgical repair
- Open best for emergency cases, but laparoscopic IPOM/TAPP is better for elective
- TEP is no good
Open
[edit | edit source]- Intraperitoneal approach
- Lower midline incision
- Hernia often well incarcerated and difficult to reduce - steep Trendelenburg and gentle persistent retraction. Can incise obturator membrane.
- Close defect primarily around obturator vessels with nonabsorbable suture, with approximation of periosteum of the superior pubic ramus and internal obturator muscle
- Coated synthetic mesh placed into the defect and secured with interrupted suture to pectineal ligament and fascia overlying pubic symphysis
- Can sometimes use local flaps to close defect e.g. periosteum or uterine ligament
Laparoscopic TAPP/IPOM
[edit | edit source]- Periumbilical Hasson
- Two 5mm trocars on each side of umbilicus lateral to semilunar line
- Gentle water pressure through a catheter placed into obturator foramen adjacent to the bowel may help reduce it
- TAPP - incise peritoneum from ipsilateral ASIS toward the medial umbilical ligament, and peel towards the obturator foramen with enough space to allow mesh placement
- IPOM - peritoneum not incised