Case 7, part 1: Complicated lower extremity wound

by nadine on July 9, 2012

This case presents a patient with a complicated lower extremity wound with soft tissue loss and underlying fractures. The cause:  a road traffic injury, an increasingly common and growing problem particularly in low and middle income countries.  Because healthy soft tissue is critical for fractures to heal,  improper treatment can result in chronic wounds and fracture nonunion.   And this in turn, may result in long-term disability.

These types of injuries are a critical problem and this case serves to illustrate a number of common plastic surgical principles and techniques.  For these reasons, the care of this patient will be described very carefully over the next several posts.

History: This patient was hit by a car.  Several bones in her foot and ankle were fractured.  In addition, the skin along the inner aspect of her right calf was degloved, creating a long flap of skin attached only by a narrow bridge of skin.

The treating orthopedic surgeon washed out the wounds, stabilized the fractures with pins and loosely sutured the skin in place.  The leg was then placed in a posterior splint. Care was taken to be sure there was adequate padding and that there was no undue compression on the skin.

A few weeks later, the splint and dressing were removed. The majority of the skin flap was not viable and debridement was done at the bedside. After a week or so of dressings with silvadene (an antibiotic ointment often used for burns), she was referred to me.

This is how the leg looked when I first saw her.

Physical Exam: Essentially the entire skin flap had died- this is typical for degloving injuries.  Unless there is healthy fascia attached to the undersurface of the skin flap, even if it looks good at the time of injury, there is usually too much trauma to the area and inadequate blood flow to the flap to maintain viability.  In this photo, the greenish/black areas are remnants of the skin flap.  There is healthy appearing granulation tissue over the rest of the wound and the surrounding intact skin looks good- without signs of infection.  The wound is a dirty wound, because of the dead tissue, but probably not an infected one- since there is no obvious infection in the surrounding skin (and she has no systemic signs of infection).  In addition, there does not seem to be exposed bone or hardware and the Achilles tendon is covered by healthy skin.  These last observations are critical- as it simplifies the wound coverage requirements (discussed later)

Before proceeding with treatment:  important considerations

1:  does the patient smoke?  she’s a non-smoker- GREAT!  Very important.  Smoking greatly slows down soft tissue and fracture healing.  So anyone with this type of injury should be counseled on the importance of refraining from all tobacco products.

2:  how is the circulation to the extremity?  Very good- she has palpable dorsalis pedis and posterior tibial pulses.  If these weren’t present, revascularization of the foot may be required to achieve healing.  This type of injury could have caused vascular injury that may not have been identified at the time of injury, so be sure to check pulses distal to the wound.

3:  Diabetes?  No.  Diabetes slows wound healing, so in patients with diabetes good blood glucose control is  critical to enhance wound healing.

4:  How is the patient’s overall nutrition?   Fine- normal albumin and prealbumin and she is at normal weight.  If suboptimal, she will need protein/vitamin supplements as appropriate.

 

Treatment options:

The first step is to clean up the wound.   Formal debridement, preferably with sedation in the operating room is best to remove all the necrotic tissue.  This will also allow full inspection of the extent of the wound- it’s possible that there is exposed hardware/bones under the dead tissue.

 

Here is the wound following debridement.  There is no exposed hardware/bones/tendons, so the             options for closure are:  allow it to heal secondarily, that is with dressings, or cover the wound with a     split thickness skin graft (STSG).  If there was exposed hardware/bones/tendons, a more complicated   closure technique- a flap wound be required.

 

The next post will discuss treatment options and what happened next….

Corresponding chapters for further information:

Chapter 6- evaluation of an acute wound

Chapter 8- nutrition

Chapter 9- taking care of wounds

Chapter 18- chronic wounds

 

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