Editing Spigelian hernia


AKA lateral ventral hernia

Herniation through the Spigelian fascia, which lies between the rectus muscle medially and semilunar line laterally, at the level of the arcuate line

== '''Anatomy/pathophysiology''' ==

* Protrusion of intra-abdominal contents through a congenital or acquired defect in the Spigelian aponeurosis
** Most commonly occurs just below the arcuate line (which is found just above the level of the ASIS)
** Two subtypes:
*** Interstitial/interparietal - does not protrude past the external oblique
*** Subcutaneous - protrudes through external oblique into subcutaneous tissue
** Typically 1-2cm in size
* Linea semilunaris - a curved line on the lateral side of rectus abdominis, extending between 9th costal cartilage to the pubic tubercle
** First described by Adrian van der Spieghel
* Spigelian aponeurosis - aponeurosis of transversus abdominis - limited laterally by linea semilunaris and medially by rectus abdominis
* Spigelian fascia is a combination of TA and IO aponeuroses


== '''Presentation''' ==

* Typically middle aged, slightly more common in females
* The usual hernia risk factors, also multiple pregnancies
* Hernia only palpable in a third of them
* Differential - haemangioma, tumour
* CT/USS will often be required
* Incarceration and strangulation will be present at diagnosis in one third

== '''Management''' ==

* No universal consensus on treatment, but most would say repair should be done once diagnosed because of risk of strangulation
* Procedure choice:
** Open anterior repair best in emergency cases - direct muscle re-approximation +/- mesh
** Laparoscopic IPOM is superior in elective cases, especially in interstitial hernias - don't need to breach external oblique. Also good for large cases.
** TEP is good for easily reducible hernias <3cm in diameter and positioned inferior to umbilicus

== '''Technique''' ==

* Open anterior
** Transverse skin incision over protrusion
** Dissect down to EO
*** Usually need to open EO to see the hernia, and will see the sac or pre-peritoneal fat in the inter-parietal plane
*** If EO is exposed and it's unclear where the hernia is, palpate for the defect, then incise EO and bluntly open the plane between EO and IO to find the hernia
*** If EO is fibrotic from previous repair, open it in a separate area and then dissect towards the defect from normal to abnormal
** Dissect sac down to hernia neck
** To place mesh between EO and IO:
*** Separate external oblique from internal oblique for a 3cm circumference
*** Close internal oblique defect with running absorbable
*** Synthetic mesh between internal and external obliques (suture to rectus medially with nonabsorbable sutures)
** To place pre-peritoneal mesh:
*** Just treat it like a standard sub-lay Ventralex repair, creating a pre-peritoneal pocket
** Close external oblique
* TAPP/IPOM
* TEP 
** Dissecting balloon superficial to posterior rectus sheath
** Keep inferior epigastrics anterior to balloon to avoid tearing
** Insufflate 12mmHg
** 5mm trocars placed in midline between umbilicus and pubic symphysis
** Reduce sac, approximate edges, place mesh
* Open intra-peritoneal

[[Category:Abdo wall and retroperitoneum]]