Inguinal hernia

Section: Abdominal wall and retroperitoneum Sub-section: Hernias Curriculum: Curriculum, page 2

Incidence

• Prevalence of 3% in men
  • 15 per 1000 population
• M:F = 25:1
• Indirect: direct in men is 2:1
• Direct hernias in women are rare
• Femoral hernias are rare in men and uncommon in women (inguinal hernias are more common in women than femoral)
  • 10% of women and 50% of men with a femoral hernia have, or will develop, an inguinal hernia
• Indirect and femoral hernias are 2 x as common on the right
  • Slower descent of the testis on the Right
  • Delayed obliteration of the process vaginalis
  • Presence of the sigmoid colon on the left blocking the femoral canal

Aetiology

• Congenital or acquired
  • Congenital
    • Lack of obliteration of processus vaginalis after testicular descent
    • Risks
      • Prematurity
      • Low birth weight
      • Collagen deficiency
      • Pelvic deformity
    • Acquired
      • Wear and tear, straining
      • Abnormal fibroblastic proliferation
      • Cigarette smoking
      • Advanced age
      • ? Malnutrition and vitamin deficiency

Classification

• Nyhus Classification 1991
  • Type I
    • Indirect hernia associated with a normal internal ring
  • Type II
    • Indirect hernia with an enlarged deep ring
    • Inferior epigastric vessels not displaced
    • The posterior wall of the inguinal canal is normal in types I & II
  • Type III - Posterior wall defect
    • IIIA - Direct
    • IIIB - Indirect with a dilated internal ring encroaching onto the posterior wall of the inguinal canal
    • IIIC Femoral

Clinical

History

• History of lump, when, where, reducible or not?
• Key is occupation and how it affects them
• R/O weight loss or malignancy
• Previous surgery

Exam

• Inguinal
  • Hernia above and medial to the pubic tubercle
  • C.f. Femoral – below and lateral
• Differentiate from scrotal lesion
  • Can’t get above it
  • Reduces on palpation
  • Positive couch impulse
  • +/- Bowel sounds on auscultation
  • Does not transilluminate

Management

Indications for surgery

• Primary management of inguinal hernia is surgical repair if there are no local or systemic contradictory conditions
  • If surgery contra-indicated, trusses may be useful
• If asymptomatic could consider a watch and wait approach for inguinal hernias (not femoral!)
  • RCT showed
    • 10% will become symptomatic per year
    • 40% will have been repair by 3 years and 70% by 10 years
    • <0.1% risk of strangulation per year
    • No increase in chronic pain for surgery vs watchful waiting
• Repair types
  • Open
  • Lichenstein tension free mesh repair
  • Various methods of suture repair
  • Herniotomy (see childhood inguinal hernia)
  • Laparoscopic
    • TAPP
    • TEP

Lichenstein Hernia Repair

• Rationale
  • Inguinal hernias are caused by a metabolic disorder, which leads to a progressive destruction of the fibroconnective tissue of the groin, making the tissue unsuitable for being used in hernia repair
  • Traditional tissue repairs are associated with undue tension at the suture line, which leads to more post-op pain, longer recovery time and higher recurrence rate

Technique

• A 5 cm to 6 cm transverse incision is made within a Langer’s line, beginning from the pubic tubercle 2 fingerbreadth above inguinal ligament
• External oblique aponeurosis opened in the line of its fibres
• Spermatic cord with its cremasteric covering, external spermatic vessels, and the genital nerve are freed from the inguinal floor and lifted
• Spermatic cord is also dissected free from the pubic bone area for approx 2 cm medial to the pubic tubercle to make room for extending the mesh beyond the pubic tubercle
• External oblique aponeurosis is dissected from the underlying internal oblique muscle and aponeurosis high enough to make room for 6-7cm mesh
• Sac is then dissected from the cord beyond its neck
• Inverted into the preperitoneal space (may require ligation /excision)
• If the sac is very large, the sac is divided at the midpoint of the inguinal canal.
• The proximal end is closed, dissected away from the cord structures, and inverted into the preperitoneal space
• Direct hernia bulge is large, it is inverted utilizing a purse-string on the transversalis fascia
  • This is only to make the floor of the inguinal canal flat in order to facilitate placement of the mesh
• First anchoring suture of the mesh fixes the mesh to the anterior rectus sheath where it inserts into the pubic bone
• Lower edge of the mesh is sutured to the inguinal ligament in a continuous fashion - ends at the lateral border of the deep ring
• Upper tail is then crossed over the lower one and are sutured together and down onto inguinal ligament , tucked under the external oblique aponeurosis
• Upper edge of the mesh is fixed in place, care is taken to keep the mesh slightly relaxed

Advantages and Disadvantages

• Post-op pain minimal
• Recurrence rate consistently < 1%
• Can be performed under local anaesthesia
• Easy to learn
• Economical
• Disadvantages
  • ?infection rate
    • No clear evidence of increased infection rate
    • BJS 1999 reviewed infected mesh-
    • All had to be removed but rate was 1 in 1000

Suture Inguinal hernia repair

• Method
  • Bassini
  • Shouldice
    • Division and double breasting of transversalis fascia
    • Then suturing conjoint tendon to inguinal ligament with continuous suture
  • Marcy
    • Simple deep ring closure

Advantages and Disadvantages

• Advantages
  • Can be performed under local anaesthesia
  • So Age is never a factor
  • Minimal equipment necessary
  • Most cost-effective repair
  • Incidence of dysejaculation and inguinodynia seen less frequently with pure tissue repairs
• Disadvantages
  • Inadequate in the treatment of femoral hernias
  • Basic pathology of herniation is not addressed
  • Higher incidence of testicular atrophy - more skeletonisation of cord
  • 1% incidence of chronic pain lasting beyond a year after surgery
  • Cannot be relied upon for recurrent inguinal hernias

Bassini Repair

• The Bassini technique for inguinal hernia repair involves suturing the transversalis fascia and the conjoined tendon to the inguinal ligament behind the spermatic cord with monofilament nonabsorbable suture.
• It also involves the so-called Tanner slide, which is a vertical relaxing incision in the anterior rectus sheath intended to prevent tension.

Shouldice repair

• Four-layer inguinal hernia repair performed with the patient under local anesthesia.
• Transversalis fascia is incised from the internal ring laterally to the pubic tubercle medially, and upper and lower flaps are created. These flaps are then overlapped (double-breasted) with two layers of sutures.
• The conjoined tendon is then sutured to the inguinal ligament, again in two overlapping layers.
  • This reinforces the posterior wall and narrows the deep inguinal ring.
• The Shouldice repair is classically done with a continuous suture of 32- to 34-gauge stainless steel wire, but synthetic monofilaments (eg, polypropylene) can also be used.
• The external oblique aponeurosis is then closed in a double-breasted fashion in front of the spermatic cord.

Laparoscopic inguinal hernia repair

TAPP Laparoscopic Repair

• Trans-abdominal pre-peritoneal patch repair
• Incise peritoneum only and create a flap to do repair, and then close peritoneum over this again
• Pre-peritoneal space is then entered by incising the peritoneum transversely from the region of the median umbilical ligament laterally
• Anterior to the hernial defect
• Peritoneal flaps then developed
• Direct and small indirect sacs fully reduced
• Larger indirect sacs are part dissected and having freed the cord structures posteriorly, circumcised
• 15 x 10 cm mesh fashioned and inserted
• Medial border of mesh adjacent to symphysis pubis
• Posterior part placed well behind internal ring
• Stapled in place
• Staples applied to the pubic bone and Cooper’s ligament
• Further staples placed into muscle layers anteriorly
• None into or posterior to the iliopubic tract
• Peritoneum then reconstituted (running suture)

TEP Laparoscopic Repair

• Total Extra-Peritoneal Repair
• Good for – Recurrent, bilateral
• Becoming more common for primary hernias
• Earlier return to work with less pain
• But ? More complications and recurrence
• Contraindicated if:
  • Hernia still irreducible once anaesthetised
  • Previous complicated pelvic surgery
  • Significant cardiovascular disease or severe COPD

Anatomy

• Space created in pre-peritoneal plane
• Safe places to staple
  • Pubic tubercle
  • Cooper’s ligament
  • Above Iliopubic tract laterally

Technique

• Entry
  • Sub-umbilical incision
  • Dissect onto rectus sheath
  • Mobilise laterally opposite to hernia side
  • Vertical incision over muscle 2cm long ≈ 2cm from midline
  • Mobilise rectus laterally
  • Finger dissection into preperitoneal space
  • Can usually reach down to symphysis
  • Insert Hasson - inflate (or insert inflation balloon to create space)
    • 20x inflate under vision, wait with tamponade, then release
  • Insert 2x 5mm ports in midline
• Disection
  • Identify & preserve inferior epigastrics, keep on superficial aspect
  • Blunt dissection to reveal & identify
    • Symphysis pubis
    • Develop retroprostatic space
    • ASIS
    • Inguinal ligament
    • Identify position of iliac vessels
    • Identify deep ring
  • Direct hernia will often reduce spontaneously
  • Indirect
    • Tease out from cord
  • Careful of perforation of peritoneum
  • Unequivocal identification of vas & vessels — Reduce sac fully or divide
• Mesh
  • Roll 10x15cm mesh on grasper, (cut 1 corner) & insert through 10mm port
  • Roll out, use cut corner for orientation
  • Staple to pubic bone (above pubic bone not directly into), Cooper’s ligament, 2cm above Iliopubic tract & laterally
  • Keep sac on peritoneal side, vessels on wall side
  • Deflate under vision - Keep mesh in position
• Remove ports
  • Close with 1 vicryl UR6 to sheath & 3-0 monocryl to skin

Complications of Hernia Repair

• Wound
  • Early
    • Seroma, haematoma, wound/mesh infection
  • Late
    • Numbness, keloid
• Testicular
  • Scrotal oedema
  • Impotency
  • Ischaemic Orchitis
  • Testicular atrophy later, esp. if divide cremasteric and don’t hitch up distal portion
  • Vas injury
• Skin
  • Paraesthesia - hard to fix
  • Reaction to prep/tape
  • Nerve entrapment
    • Neuroma/Chronic pain
• Open
  • Ilioinguinal/Iliohypogastric
  • Lap
  • Lat Fem Cut. Nerve
    • Meralgia Parasthetica/genitofemoral
• Bowel/bladder injury
• Urinary retention/UTI
• Recurrence

Post-Hernia Repair Groin Pain

• Iliohypogastric Nerve (T12, L1)
  • First branch off lumbar plexus
  • Arises lateral border of psoas, travels behind kidney, then pierces fascia to reach neurovascular plane
  • Pierces external oblique aponeurosis 2.5cm above superficial ring
  • To suprapubic region, skin over lower rectus and mons
  • Also supplies Internal Oblique (damage can precipitate hernia)
• Ilioinguinal Nerve (L1) – Collateral branch of Iliohypogastric
  • Second branch off lumbar plexus, lateral border of psoas
  • Pierces lower border of internal oblique and enters inguinal canal from the side (Not through Deep Ring!)
  • Male
    • Sensation to skin over root of penis and anterior 1/3 of scrotum, and upper medial thigh
    • Muscular branches to Internal Oblique and Transverse Abdominis – Strengthen conjoint tendon
  • Female
    • Skin covering Mons Pubis and Labia Majora
• Lateral Femoral Cutaneous Nerve (L2, L3)
  • Third branch off lumbar plexus, Lateral border of psoas, on iliacus
  • Passes through inguinal ligament to anterior thigh
  • Supplies parietal peritoneum of iliac fossa and skin of the lateral thigh
  • Meralgia Parasthetica – pain and altered sensation of lateral thigh due to compression of Lateral Femoral Cutaneous Nerve
• Genitofemoral Nerve (Genital branch) (L1, L2)
  • Arises anterior to psoas (deep to psoas fascia)
  • Supplies motor to cremaster and scrotal skin
• Management (> 6 weeks = Chronic pain)
  • Neuropathic meds (Amitriptyline, Gabapentin)
  • Nerve block - may break the cycle of pain
  • Surgery – Neurotomy +/- Remove old mesh and replace with new mesh

Recurrence

• Risk Factors for Recurrence
  • Age (older age)
  • Duration of hernia (short duration)
  • Type of hernia (Femoral more than Inguinal)
  • Coexisting medical illness
• In children, the risk factors were
  • Age (very young)
  • Gender (male)
  • Short duration of hernia
  • Side (right side)

Lap vs Open

Laparoscopic • Pros o Smaller scars o Less hematoma, seroma, wound infection o Shorter hospital stay o Faster return to activities by one week o Less chronic pain (half from 7%) – possibly even better since using absorbable tacking devices o Less numbness – ie: less ilioinguinal & iliohypogastric nerve injury o Less risk of ischemic orchitis o Can inspect contralateral side and identify hernia defects and fix at the same operation (controversial) • Cons o Not all surgeons do them o Requires GA o Longer operation by 15 minutes o Increased incidence of vascular or visceral injury (studies for this were looking at TAPP & TEP – visceral injury should be rare in TEP unless peritoneum breached) o Port site hernia – very few cases reported