Chapter 25 - Principles fo Plastic Reconstructive Surgery Flashcards
What is the primary goal of plastic and reconstructive surgery as described in the text?
Achieving wound closure and restoring function.
Why is understanding the general process of wound healing critical in equine surgery?
It forms the basis for developing an effective treatment plan.
What factors must be considered when deciding on wound management?
Type of injury, location, degree of contamination, age of the wound, integrity of blood supply, and skin loss.
What is a significant challenge in managing soft tissue injuries in horses compared to humans?
The physical size of equine patients and their environment.
What are the different methods of wound closure mentioned in the text?
Primary closure,
delayed primary closure,
secondary closure,
healing by second intention.
When should immediate wound closure be considered?
For clean or clean-contaminated wounds with adequate blood supply.
What mistake do equine practitioners often make in early wound management?
Premature closure of heavily traumatized or contaminated wounds.
How long should wounds be managed before considering closure for better outcomes?
1 to 3 days.
What is associated with delayed closure after the appearance of granulation tissue?
Reduced wound sepsis.
What is often the best treatment option for wounds with significant skin deficits?
Secondary closure or open wound management.
What complications may arise from second-intention healing?
Exuberant granulation tissue and delays in contraction and epithelialization.
How can reconstructive and skin-mobilizing techniques help in wound management?
They minimize cosmetic and functional shortcomings.
What are some clinical situations where reconstructive procedures are utilized besides traumatic wounds?
Planned excision of skin lesions.
What are the benefits of using reconstructive procedures in wound management?
Improved cosmetic appearance, function, and reduced healing time.
What types of vessels supply the skin in mammals?
Perforating musculocutaneous vessels
and direct cutaneous vessels.
How is horse skin primarily supplied?
By direct cutaneous arteries.
What is the role of the superficial plexus mentioned in the text?
It is part of the thermoregulatory system and maintains blood supply integrity.
What are skin flaps and what role do they play in equine surgery?
Skin flaps are tissue sections used in reconstructive surgery to cover defects and improve healing.
How do viscoelastic properties of skin influence surgical outcomes?
They affect how skin responds to tension and stress, influencing incision healing.
What are the three structural components of skin that provide its properties?
Collagen, elastic fibers, and ground substance (primarily proteoglycans).
Define static tension in the context of skin properties.
Tension that results from the skin clinging to the underlying body.
How do dynamic tension and static tension differ?
Dynamic tension is caused by underlying muscle pull, resulting in visible skin wrinkles.
What are Langer lines, and why are they significant in surgery?
Lines of maximal tension that guide incision placement to improve healing and minimize scarring.
How does skin anisotropy influence surgical incisions?
It affects how skin tension reacts to movement and surgical cuts.
What effect does incision angle have on wound healing?
Incisions parallel to tension lines gap less, heal better, and result in finer scars than those made at right angles.
What does the text suggest about the relationship between wound edges and tension during débridement?
Avoid smoothing irregular edges to prevent increased tension during closure.
What happens to incisions made at right angles to lines of tension?
They gape widely and require more sutures, resulting in unsightly scars.
What is the benefit of delaying closure of a wound until granulation tissue appears?
It can reduce complications and promote better healing.
How many plexus exist in the dermis?
3 plexus:
deep subcutaneous plexus
the middle cutaneous plexus
superficial subpapillary plexus
What are the skin flaps developed based on the major cutanoeus arteries of the trunk?
Vascularized free flaps
island arterial flaps
Axial pattern flaps
A skin flap based on the cutaneous portion of the caudal branch of the _____ _____ _______ artery has been described in experimental studies of a vascularized free tissue transfer
deep circumflex iliac artery
What are teh 3 structural components that impart tension and viscoelascticity?
groudn substance
collagen
elastic fibers
What are viscoelastic materials?
viscoelastic materials are those for which the relationship between stress and strain depends on time.
If the stress is held constant, the strain increases with time this is _________ (1w)
creep
if strain is held constant, the stress decreases with time this is _______ (1w)
relaxation
Tension is
the magnitude of force skin can exert
There are 2 types of skin tension name them
static tension (skin clinging to the underlying body
dynamic tension which results from the pull of the underlying muscles and is seen as wrinkkles in the skin
What does it mean: skin is anisotropic
lacking similar properties in all directions
skin tension lines are influenced by
muscle contraction, movement of joints, and other external forces
Langer lines are more accurately referred to as
relaxed skin tension lines
When excising an elliptical piece of skin, closure is facilitated by ensuring that the long axis of the ellipse is aligned to________________ (2w)
Langer lines
Mechanical creep is a biomechanical property of skin - give definition
which allows it to stretch beyond its normal limits of extensibility under a constant load.
Biological creep differs from mechanical creep in that the skin does not stretch, but instead increases area of coverage by increasing 3 things name them
epidermal mitotic activity,
upregulation of blood vessels,
and increasing dermal cell numbers, resulting in skin development (pregnancy, body wall hernias)
When cosmetic appearance is important, sutures should be removed by ____ to ___days, regardless of suture type.
When cosmetic appearance is important, sutures should be removed by 10 to 14 days, regardless of suture type.
Apposition is best obtained by maintaining the needle ___________/(1w) to the skin during skin penetration
Apposition is best obtained by maintaining the needle perpendicular to the skin during skin penetration
Tissue strength or suture size or number of suture bites is a more important determinant as to whether or not a wound will dehisce?
Tissue strength and not suture size or number of suture bites is a more important determinant as to whether or not a wound will dehisce
More sutures are required in thinner skin or in thicker skin?
More sutures are required in thinner skin than in thicker skin
define intrinsic tension
define extrinsic tension
Tension on sutures can lead to 3 things (negative) name them
- Necrosis (lack of blood supply
- increasing edema
- Decreasing tissue perfusion
Subcutilar and intradermal suture objective is
minimize dead space
Simple interrupeted sutures have been shown to have 3 good characteristics
Excellent tissue apposition
compromiss less microvasculature
greater tensile strenght
Simple continuous in case of knot failure a breakdown happens but also other disadvantages name them (3)
increment EDEMA + COMPROMISED CIRCULATION + PROLONGING EFFECT OF INFLAMMATORY PHASE OF WOUND HEALING
Corner suture is also called
3 point or half buried mattress suture
In the corner suture it starts as routine horizontal matteress but instead of penetrating the full thickness, only a ________ __________ _____(3w)
only a partial thickness bite
Simple interrupted
interrupted intradermal/subcuticular
Figure 25-2. Corner suture used to minimize vascular compromise to the tip of the flap.
Figure 25-3. A stent bandage consists of rolled up sterile gauze sponges sutured with a large, simple continuous suture pattern over an incision closed with simple interrupted sutures.
A barbed suture equipped with a loop at one end for fixation of the first suture loop and unidirectional barbs throughout the length of the suture strand can be used for tissue apposition. These barbed suture materials allow knotless suturing
cushing
Gambee; this pattern can be used as an appositional suture pattern for skin (a) or
Gambee; this pattern can be used as an appositional suture pattern for intestine
Allgower corium vertical mattress
Interrupted vertical mattress
(E) walking suture - Walking sutures have been described for closing skin defects in small animals, particularly in areas where the skin fits loosely, such as the trunk
The small incisions are made in staggered rows, parallel to the wound edge
Figure 25-6. V-to-Y-plasty for tension relief. With this technique, tissue is mobilized in the direction of the arrow.
Figure 57-12. V-to-Y plasty for ectropion. (A) The area of ectropion is identified. (B) The V-incision is made with a scalpel. (C) The skin flap is elevated, and underlying cicatricial tissue is excised using scissors. (D) The skin flap is advanced to relieve skin tension. Closure is performed in a Y pattern
Figure 25-4. Fusiform excision. After excision, the skin is undermined to facilitate closure of the defect. The optimal length-to-width ratio of the fusiform defect is 4 : 1.
Figure 25-8. Methods for removal of dog-ears. (A) The dog-ear is held securely, elevated and is excised level with the surrounding skin, leaving a small fusiform defect to close. (B) The dog-ear is bisected to form two small triangular flaps, which are resected level with the skin surface.
Figure 25-9. Simple bipedicle flap. This can be used with a single incision, as depicted here, or a second incision can be made on the opposite side of the primary defect. By using two relaxing incisions, it may be possible to close the secondary defects.
Figure 25-11. Rotation flap. This pedicle flap is semicircular and can be used to cover small defects.
Figure 25-10. Sliding H-plasty. Burow triangles are created and excised to prevent dog-ear formation after mobilization of the skin.
Figure 25-12. Transposition flap. This rectangular pedicle flap can be rotated up to 180 degrees to cover a defect.
Figure 25-13. Interpolating flap. (A) A pedicle flap is lifted from the skin adjacent to the defect. (B) The flap bridges normal tissue to cover the defect. (C) After the defect has healed, the pedicle is resected and the incised edges are sutured.
