ABDOMINAL WALL DEFECT

RECONSTRUCTION

Dr Subhakanta Mohapatra

Mch plastic surgery, IPGME&R,SSKM Hospital

kolkata

ABDOMINAL WALL ANATOMY

Skin Subcutaneous fatty layer (Camper’s

fascia) Deep fibrous layer/ Scarpa’s fascia

(superficial fascia) Adipose tissue Deep fascia(aponeurotic fascia) Paired flat muscles Fascia transversalis peritoneum

Rectus abdominis muscle

External oblique muscle

Internal oblique muscle

Transverse abdominis

Superficial & deep anatomy of the abdomen showing muscular layers & fascial layers

The rectus sheath above & below arcuate line

INDICATION OF ABDOMINAL WALL RECONSTRUCTION

Hernia repair Tumor defect

Congenital defect

Traumatic defect

PRIMARY SUTURE REPAIR

Not recommended now

High (25-63%) recurrence, even in <5cm defect

May be indicated for <3cm defect

COMPONENT SEPARATIONB/L mobilisation of Rectus abdominis

muscles as musculo-fascial, bipedicled,neurotized flap

Degloving of skin & SC tissue up to anterior / mid axillary line

Fasciotomy (1-2 cm lateral to linea semilunaris) with cautery/scissors to

separate EO from RA.

CONTD…Entering in avascular plane in b/w EO & IO

(without injuring IO fascia or muscle)

Posterior rectus sheath incision( few mm lateral to free edge of fascia) – gives

additional 2 cm mobility.

Further mobilisation – Sub-periosteally off the costal margin & symphysis pubis

Requires reinforcement(underlay/onlay)

CONTD….. Intraperitoneal adhesions – regarded as a

component & must be separated.

Wide adhesiolysis up to paracolic gutter is an important step

If stoma present & to be preserved – wide soft tisssue attachment should be maintained around the stoma

If stoma to be created through rectus component separation Stoma exteriorization after fascia closure

Maximal U/L rectus complex mobility with component separation of EO & IO muscles to the posterior axillary line

Midline closure at Linea alba after component separation

CONTD…

Disadv Needs wide underminingMore chance of seromaSkin edge ischaemia

Recent advanceEndoscopic & minimally invasive

component separation

PERFORATOR SPARING COMPONENT SEPARATION Peri-umbilical perforator spared Single , large caliber Arising from rectus abdominis in each

hemiabdomen Advantage

Minimises ischaemic soft tissue complications Useful for pts with comorbidities

Disadvantage More operative time Limit the degree of release (minor extent)

Underlay mesh used here.

1. EO perforator 2. DIEA perforator with large musculocutaneous branch 3. intramuscular branching with small musculocutaneous perforator 4. large musculocutaneous branch with no intramuscular branches 5. septocutaneous perforators

AUTOLOGOUS GRAFT Fascia lata graft

Broad & dense fascia of TFL

28 × 14 cm - max size

5 -10 cm length should be left, to prevent lateral knee instability

Drains in donor site

Can be used in contaminated cases

32 % recurrence rate

MESH

availability strength

No donor site

morbidity

Host tissue incorporatio

n

PROSTHETIC MESH MATERIAL

Polypropelene ePTFE

Larger pore size Strong More resistant to

infection Less seroma Can not be placed

directly on the bowel

Host tissue incorporation- present

Microporous More stronger Less resistant to

infection

More seroma Soft, flexible,conforming

quality,minimal tissue ingrowth. So can be placed directly on bowel.

Absent

MESH PLACEMENT TECHNIQUES

onlay inlay

underlay

sandwich

A.Only B.inlay C.underlay

ONLAY Mesh placed above the fascia,from one EO to other

EO

Quilting sutures between onlay & fascia (to decrease seroma)

Drains above & below onlay

Adv ease of use no full thickness U sutures avoids direct contact with bowel

Disadv wide tissue undermining contaminated, if skin breaks down pressure required to disrupt mesh from abdominal

wall is less.

Component separation with onlay mesh

INLAY

Excision of hernia sac

Identification of healthy fascial margins

Tensionless repair

Adv - Avoids wide undermining

Disadv - Significant tension to mesh fascia interface (weakest point),so high recurrence

RETRORECTUS UNDERLAY By Rives & Stopa

Used in increasing frequency

Mesh - between posterior rectus sheath & rectus muscle(within the limits of rectus sheath)

Atleast 4 cm contact between mesh & fascia

Below arcuate line – placed in preperitoneal space

Recurrence rate - < 10 %

Retrorectus underlay

RETRO… Adv :

Strength layer placed in proximity to muscle

Not in contact with bowel

Disadv : No broad resurfacing of abdominal wall secondary hernia lateral to rectus sheath

INTRAPERITONEAL UNDERLAY

Commonly used in open & laparoscopic approach

Span from one EO to other EO

Full thickness U sutures by Reverdin needle (from abdominal wall down in to peritoneum, in to mesh, & back in to abdominal wall)

Mesh should be tensioned (for passive closure of muscles in midline)

Recurrence - < 5%

U suture by Reverdin needle

CONTD….

AdvLarge underlay allowing better tissue

ingrowthMore secure mesh fascial interface

Disadv – Ring of U sutures may strangulate the

fasciaNeuroma – full thickness suture - injury to

nerve

Intraperitoneal underlay

LAPAROSCOPIC REPAIR Intraperitoneal mesh underlay

Mesh secured by tacking device /transabdominal suture/both

Adv : ↓ hospital stay, ↓wound complication Disadv :

No restoration of dynamic abdominal wall

No cosmetic improvement by excising excess tissue & scar

Recurrence : 2-4 %

BIOPROSTHETICS Derived from human & animal tissues Human acellular dermis(Alloderm)

Less adhesions – intraperitoneal use possible Size limitations (small size patch)

Porcine submucosa Come in larger sheet

Adv Resistance to infection Tolerance of cutaneous exposure Mechanical stability

Disadv High cost Lack of long term follow up study

EXPANDER Provides well vascularised, autologous,

innervated tissue Indicated for pts having both fascial & soft

tissue deficiency In congenital defect & large hernias

Site – in S.C space (over fascia) – commonly done

Intermuscular

both fascia & soft tissue expansionbetween EO & IO not commonly done

LOCAL FLAPS

Upper third defect – Thoraco epigastric flap

- EO flap(rotational flap) Middle third defect – ilio-lumbar bipedicled

flap (based on superficial circumflex iliac & lumbar perforators)

Lower third defect – SIEA ,DIEA flap,groin flap

Lateral wall defect – Rectus abdominis flap

Paramedian defect - EO flap(advancement flap)

TFL FLAP pedicled/free muscle/fascial/fascio cutaneous Adv

Dispensable good arc of rotation

Disadv no dynamic reconstruction distal third – unreliable donor site morbidity

Complications seroma/hematoma/lateral knee

instability/STSG loss recurrence – 9- 42%

OTHER FLAPS Rectus femoris musculofascial /

musculofasciocutaneous flap - Free/ ( pedicled flap for lower 2/3rd defect)

ALT flap with mesh – free/(pedicled – lower abdominal defect)

LD flap free/(pedicled – upper abdominal defect)

Gracilis muscle/musculofasciocutaneous flap - lower third small defect

A. TFL flap B.ALT flap C. RF flap (pedicled)

ABDOMINAL WALL TRANSPLANTATION

In conjuction with other transplantation

Pedicle – inferior epigastric vessel

Lifelong immunosuppression

ADJUNCTS TO REPAIR

Drain :Between mesh & fasciaAtleast 2 additional subcutaneous drains (in component separation) In paracolic gutters

Fibrin based tissue glues in S.C space (to prevent seroma)

Quilting sutures (from skin flap down to fascia )

PERI-OPERATIVE M/N DVT prophylaxis

Prophylactic antibiotic 30 mins before surgery Consideration of extubation on 1st post op day

Intra abdominal pressure monitoring Drain

Larger drain for potential hematoma area Smaller drain for seroma risk area Kept at least 1wk

Early enteral feeding/ TPN

CONTD…

Abdominal bindermay be given only after 48 – 96 hrs

Analgesia to improve pulmonary toilet, pain

control,ileus

Muscle relaxationUse of botulinum toxin at the time or 1wk

before operation

Activity Extremely limited activity for 1st 6 wks

COMPLICATIONS

Recurrence

Wound breakdown

Adhesions

Seroma(more in underlay)

Spigelian hernia

Pain

Mesh migration(rare)

M/N OF COMPLICATIONS Wound breakdown :

Local wound care & hyperbaric oxygen for biological/light weight mesh

Synthetic mesh - More likely to be removed (if periprosthetic infection develops)

Adhesions :

Prevention – by interposing omentum in between bowel & abdominal wall

Biologic mesh & fascial grafts – lower adhesions

Seroma : Serial aspiration Sclerosant Excision of pseudobursa

CONTD… Chronic pain :

Prevention - using long term absorbable sutures

T/t – Neuronal stabilising medications Massage,desensitisation,US pulses,

acupuncture Surgery - removal of offending

suture,staple,mesh neurolysis/neurectomy of involved

nerve

SECONDARY PROCEDURES

Scar revision Contour improvement/

panniculectomy Correction of diastases Umbilical reconstruction Amelioration of pain

SWISS CHEESE DEFECTS

Multiple small fascial defects

When one defect repaired, the other unrepaired defect enlarge

Recurrence due to failure of diagnosis of multiple defects

Pre op CT scan confirms location & number of defects

Wider dissection to identify occult hernia

Laparoscopic view - broader view

CONCLUSIONRegional flap

Component separtation

Fascial grafts

Be closed primarily