Plastic surgery introduction (Grafts and Flaps).pptx

Basics of Grafts and Flaps

1. Presenter - DR.MANOJA JR2 Moderator – DR CHANDRALEKHA MS MCH Basics of Grafts & Flaps

2. Introduction Plastikos (Greek) – to mould Sushrutha (700- 600BC) – Sushruta Samhita ( sanubandhen jeevitah ) – through continuity it survives- importance of pedicle for flap Bringer & Marburg (1823) – used FTSG from buttocks for nasal reconstruction. Diffenbach (1829-1845)(series of articles)- V-Y Plasty & Indian forehead flap & cheek rotational flap 1943: Medawar and Gibson, studied rejection phenomena in body’s immune mechanism on skin grafts. 1964: Tanner, Vandeput and Olley developed a skin graft mesher.

3. Anatomy of skin largest organ in the body (weight - 2 kg) surface area -1.72 sq. meters (adult male). Two layers, epidermis (ectoderm) and dermis (mesoderm) Avascular epidermis – depends on underlying dermal layer for nourishment by diffusion. Gel-like ground substance (mucopolysaccharides, chondroitin sulfates and glycoproteins surrounds the various components of the dermis. Ridge & groove interdigitations prevent the stripping off of the epidermis from the dermis

4. Skin tension Important factor in assessing nature of scar. Described by langer in 1861 Known as langer lines / tension lines / cleavage lines Surgeons plan incision – tension across is minimum. Creases form – if tension at right angles is minimum. Scars aligning crease lines – better aesthetic outcome.

5. Effects of increased tension on skin Stretching of skin – permanent ( lymphedema, and adiposity) Blanching – increased tension to skin – obstructs dermal flow – necrosis. Rupture of dermis – causing striae / stretch marks Undermining wound edges – tension free closure. large defect closure – skin flaps.

6. Anisotropy Skin extensibility varies in different parts of body / age / gender. Return of skin to its relaxed state. Replaced by skin laxity as age progresses. Uses – complete closure of skin defect, without importing tissue from other site. Pinch test - Assessment of extensibility Greater extensibility – greater ease of closure.

7. Ladder of reconstruction options for wound closure. begins with the simplest and progressing up the “reconstructive ladder” to the more complex.

8. Reconstruction elevator Ascend from the simplest to complex techniques, with the freedom to ascend directly to the chosen level of complexity Decision - based upon the needs of the patient only. Demonstrates an evolution in thinking, advanced techniques and progressive technology.

9. Definitions Graft : It is a tissue of epidermis and varying amount of dermis that is detached from its own blood supply and placed in a new area with new blood supply Flap : Any tissue used for reconstruction or wound closure that retains all or part of its original blood supply after the tissue has been moved to the recipient location

10. Grafts skin graft consists of epidermis and some (STSG) or all of the dermis (FTSG). completely devascularized, replaced in another location.

11. Partial thickness (Split Thickness Skin Graft STSG or SSG): (whole of epidermis + part of dermis). Full thickness (Full Thickness Skin Graft FTSG or FTG): Contains whole of epidermis and whole of dermis (Wolff-Krause grafts) GRAFTS THICKNESS (INCHES) Millimetre Ultra thin / epidermal graft 0.003-0.006 0.08 – 0.15 Thin grafts (Thiersch grafts) 0.008 - 0.012 0.2– 0.3 Intermediate grafts 0.012 – 0.016 0.3 – 0.45 Thick grafts (Padgett grafts) 0.016 - 0.020 0.45 – 0.75

12. Mechanism of graft “TAKE ” Serum Imbibition (till 48hrs) Both O2 & nutrition diffuse into graft, leaving behind fibrin. Results in graft edema & 40% increase in weight, later decreases due to revascularisation INOSCULATION / KISSING CAPILLARIES (48 – 72hrs) NEOVASCULARIZATION Maturation ( 1yr – several years) Contraction Remodelling Hypertrophy / hyperpigmented.

13. Imbibition In this phase as fibrinogen changes to fibrin that fixes the skin graft on to wound bed in absence of real plasmatic flow Skin graft gains upto 40% of their initial weight within first 24hrs after g rafting and then this gain is reduced to 5% at 1 st week post grafting In first hours, passive absorption of serum from wound bed causes edema which resolves when the revasularisation is functional

14. Inosculation and capillary growth At 48hrs Linking of host and graft through fibrin layer Capillary buds from recipient bed contact graft vessels Neovascularisation Formation of new vascular channels by invasion of graft Combination of old and new –revascularisation Fibroblast proliferation : conversion of fibrin adhesion to fibrin tissue attachment

15. Contraction Primary contraction Immediate recoil of freshly harvested grafts Result of the elastin in the dermis. Dermis in the graft, proportional to primary contraction that will be experienced . Secondary contraction contraction of a healed graft result of myofibroblast activity. FTSG contracts more on initial harvest (primary contraction) but less on healing (secondary contracture) than a split-thickness skin.

16. INDICATIONS Primary closure not possible Healing by secondary intension – impair function / adverse cosmetic results. Burn raw area Secondary defects following flap harvests. CONTRAINDICATION Exposed vital structures (neurovascular bundle, tendons, joints, bone without periosteum) Donor site infection Recipient site infection (streptococci) Excess bleeding at recipient site. Malignant / ischemic wounds. Malnutrition / anemia.

17. Graft Donor site FTSG donor sites must be closed primarily, thus smaller in size. Dermis never regenerates In STSG – donor site heals by epidermal regeneration, from sweat glands & hair follicles. Graft site takes about 2 weeks to heal. covered with nonstick paraffin gauze and gauze rung out in adrenaline (1 in 200,000) is wrapped over it for hemostasis. Later removed and the paraffin gauze is covered with layers of absorbent gauze followed by Gamgee cotton pads and finally wrapped by a bandage. Dressing opened at 12 – 14days .

18. Wound Bed Preparation (WBP) Principle for WBP – T I M E T – Tissue (non viable/deficient) I – infections / inflammation M – moisture imbalance. E – Edge of wound (undermined/ Non Advancing).

19. Tissue

20. Causes of skin graft failure Poor Graft Bed preparation Poor graft to bed contact Movement – Absolute immobilization required for graft uptake (5days) Infection - number of bacteria < 1000/gram of tissue, graft ‘take’ is uneventful. Unacceptable if infection 1,00,000/gm tissue. Presence of B-Hemolytic streptococci (absolute contraindication)

21. Changes of skin graft after successful TAKE Contraction Hyper pigmentation. Epithelial appendages sweat and sebaceous glands degenerate upon grafting. However, in a FTSG - gland has been transferred in entirety, regenerate over a period of time hairs are likely to grow only if the root is preserved which is more likely in an FTG. SSG is unlikely to grow hair. Reinnervation – several months to years, better in FTG compared to SSG.

22. Composite skin graft : combination of skin and another tissue type such as fat or cartilage. Commonly used composite skin graft is helical root of ear to reconstruct the alar of nose following skin cancer excision. Hair bearing composite scalp graft can be used to reconstruct an eye brow. Other grafts- Nerve graft Tendon graft Cartilage graft

23. Nerve graft reconstruct –brachial plexus and fascial palsy Common used donor nerves include – sural nerve, medial antebrachial cutaneous nerve Sensory branch of post interosseous nerve – ideal for digital graft . Tendon graft Commonly used – palmaris longus ,extensor digitorum longus and plantaris

24. FLAPS Tissue with intact / resected vascular pedicle. Parts Pedicle Paddle Reconstructive steps must be planned in reverse order Inset of Bespoke pattern of proposed flap paddle in the defect. Then identify the position of pedicle Mark outline of the flap paddle at donor site.

25. Five C’s methodology is useful flap classification system based on their circulation , composition ,contiguity , contour and conditioning Circulation – random flap have no named blood supply while axial flap has dominant feeding vessel Composition – cutaneous , fasciocutaneous , fascial musculo cutaneous muscle , osseocutaneous , osseous , omentum / bowel. Contiguity – local ( where flap shares a side with defect ), regional (where the flap is near but not immediately adjacent to defect ) distant ( where the flap is far from the defect and can be pedicled or free

26. Contour – flap is transferred into the defect-advancement Conditioning – flap is delayed by partially elevating and resetting the flap prior to definitive elevation and transfer. delay enables a larger flap to be harvested by improving its blood supply

27. Classification of flaps

28. Flap TAKE Gradual linkup of tissue elements b/w flap and recipient bed . Sensory recovery of flap – provide protective sensibility, even sensory neurorrhaphy not performed. Neovascularization from recipient bed - Vascular pedicle may be divided after sufficient period (2wks).

29. Biogeometry It is integration and summation of biological and geometrical factors that govern the logic involved in efficient selection, design, construction and transfer of surgical flaps

30. Rotation flap Rotation /transposition and interpolation flaps have in common – Pivot point & arc through which flap is rotated radius of this arc is the line of greatest tension of the flap . Back cut / burow triangle – used to reduce tension along radius of flap. Rotation arc –(2-4) times greater than affected limb arc

31. Transposition flap Rectangular flap rotated on a pivot point More the flap is rotated , shorter it becomes

32. Local / rotational flap Free flap

33. Vascular territories Taylors group (1987)- identified 3D unit of tissue, supplied by named vessels “Angiosomes” Total – 40 units ( subdivided into 376)

34. angiosomes Angiosomes – interconnected via anastomoses (choke vessels) Flap size could be increased – including adjacent angiosomes Delay phenomenon – preliminary surgical intervention, portion of vascular supply is divided before definitive elevation of flap Vasculosome – elevating tissue based on axial vessels present every tissue unit

35. Based on blood supply Arteries reach surgical flap – 2 basic ways . Musculocutaneous – artery travel perpendicular through muscle to reach skin. Septocutaneous – travel in b/w intermuscular fascia. Random – derives from dermal subdermal vascular plexus.

36. musculocutaneous flaps (Mathes & Nahai Classification) Muscle flap It has independent intrinsic blood supply. It provides better structural and functional results to the recipient site Less still & more malleable. Classified based on vascular pedicle Large muscle with dominant pedicle supplying most of flap (I, III, V) – MOST USEFUL

37. Cormack and lamberty classification

38. Perforator flap Evolves as improvement over musculocutaneous & fasciocutaneous flaps. Perforator is a blood vessel passing through deep fascia. Direct perforators – travel directly from mother vessel Indirect perforators – supply deep structures. Rely on evidence, neither muscle / fascia necessary for flap survival. Advantages – Preservation of functional muscle & fascia at donor site. Disadvantage – Difficult dissection.

39. Local flaps Transposition flap – most basic design ,leaving a graftable donor site Z plasty – for lengthening scars or tissues Rhomboid flap – cheek , temple , back and flat surface defects Advancement flaps-for flexor surfaces; may need triangles excised at base to make it work ( commonly called burrow’s triangle ) V to y advancement common for fingertoes and extremites Bilobed flap- for convex surfaces Bipedicle flap – eyelids

40. Post operative flap monitoring

41. Causes of flap failure

42. conclusion

43. References Principles and advances in plastic surgery (vol I) Sabiston Text book of surgery 21 edition

44. Thank you