9 – Tension Relief and Plasties

Question 1

Excessive tension

Answer 1

• Prevents wound closure
• Can lead to
  o dehiscence of sutured wounds
  o scarring and strictures
• Can compromise blood flow: slows healing and may cause necrosis
• Can have a tourniquet effect on distal extremities
• Can restrict movement (ex. due to fibrosis)

Question 2

What affects tension?

Answer 2

• Species and breed
  o Horses: don’t have much extra skin
  o Cats + hamsters: lots of extra skin
  o Sharpeis: lots of extra skin
• Location on the body
• Orientation of the wound

Question 3

Line of tension

Answer 3

• Wounds usually close best if closed along (parallel to) lines of tension
• *this way tension pulls the wound together rather than pulling it apart
• Do a pinch test to check skin tension in all directions

Question 4

Planning surgery: find what works

Answer 4

• Use Backhaus (penetrating) towel clamps or a few deep subcutaneous sutures to explore closing possibilities
• If you find tension is significant in all directions=USE another strategy for wound management

Question 5

How can you manage tension? (least to most ‘aggressive’)

Answer 5

• Undermining
• Walking sutures
• Skin stretching
• Releasing incisions
• Plasties
• Flap closure
• Free grafting

Question 6

Undermining

Answer 6

• Undermine perpendicular to lines of tension
• Undermine deep to cutaneous muscle layer if possible
• *beyond a certain point, undermining further won’t help

Question 7

Walking sutures

Answer 7

• Obliterate dead space
• Distribute tensile forces throughout the wound
• *facilitate progressive advancement of undermined skin into the wound defect
• *”drawstring effect”

Question 8

Tissue expansion and skin stretching

Answer 8

• Skin is viscoelastic
• You can get it to stretch more over several DAYS than you can over a couple of minutes

Question 9

Tissue expanders

Answer 9

• Ballon implanted beneath skin next to where you need skin to go
• Ballon is gradually inflated with saline over several weeks
• Skin stretches above balloon
• Balloon removed when skin is moved
• *some will imbibe fluid from the tissues instead

Question 10

Presuturing

Answer 10

• Large mattress or lambert sutures
• Fold up skin on either side of defect
• 3-5cm from defect
• 24-75 hours then remove mass

Question 11

Adjustable sutures

Answer 11

• Buttons, split shot sinkers (tin, not lead)
  o Pulls edges together over a period of days
  o “close” the sinker on the suture
• Adherent skin pads applied ~10cm on either side of wound
  o Elastic cables connect pads and held in place under tension with Velcro
  o Leave in place 48-72hrs, increasing tension 3x/day

Question 12

Releasing incisions

Answer 12

• Sometimes it is more critical to have intact skin in a certain area than in adjacent areas
• To help close primary incisions, you can incise adjacent skin and leave the secondary incisions open
• *avoid leaving a narrow strip of skin between the 2 incision (otherwise it will die)

Question 13

Plasties

Answer 13

• Useful when wounds are adjacent to structures that will not tolerate tension
  o Anus
  o Prepuce
  o Eyelids

Question 14

V-Y plasty (Or U-Y plasty)

Answer 14

• Decreases tension in one direction, increases tension in perpendicular direction

Question 15

Y-U plasty

Answer 15

• Same idea as V-Y, but backwards
• *good for making narrow things WIDER

Question 16

Z-plasty

Answer 16

• Decreases tension in one direction at the expense of increased tension in another (like Y-U, U-Y)
• *good for treating contracture due to a limiting scar
• Make about 60degree angle flaps