AssessmentsLeg ulcers: Clinical practice
USMLE® Step 2 style questions USMLE
A 34-year-old man presents to the emergency department for evaluation of pain in the right lower extremity. The patient was running on the beach without shoes over the past weekend and sustained a small laceration to the bottom of the foot. Over the past 24 hours, he has been experiencing severe pain and swelling of the foot to the point that he is unable to bear weight. He is otherwise healthy and does not smoke, consume alcohol, or use illicit substances. Temperature is 38.6°C (101.5°F), pulse is 109/min, respirations are 22/min, and blood pressure is 131/72 mmHg. On physical examination, a 3 cm x 3 cm area of erythema is noted on the underside of the right foot. The patient is exquisitely tender to palpation over the entire aspect of the right foot extending to the mid tibia. A radiograph of the right foot is obtained and demonstrates the following finding:
Reproduced from: Radiopaedia
Which of the following is the most appropriate treatment for this patient’s clinical condition?
Content Reviewers:Rishi Desai, MD, MPH
An ulcer is an unhealed sore or open wound that may appear on the skin or mucosal surfaces due to destruction of the epidermis that extends into the dermis and may reach subcutaneous fat or deeper tissues.
Skin ulcers may take a very long time to heal. For optimal wound healing, the wound bed needs to be well vascularized, free of devitalized tissue, clear of infection, and moist.
The general approach to treating any ulcer starts from wound debridement to remove the accumulation of devitalized tissue, as well as decreasing the bacterial load to prevent infections.
This is usually done through irrigation, typically warm isotonic saline solution; while surgical debridement with a scalpel or other sharp instruments is done for removing large areas of necrotic tissue, for chronic non healing ulcers, or when there are signs of infection.
In addition, individuals with infected ulcers should have wound cultures sent and should get started on antibiotic therapy.
Then, a dressing is applied to the ulcer to help the wound heal more quickly by providing a sterile, breathable and moist environment, as well as reducing the risk of infection. Dressings are typically changed daily or every other day.
When gangrene has set in, aggressive debridement or amputation of the affected area may be required.
Skin ulcers most often appear on the legs, and can result from multiple causes.
Biopsies are not usually necessary for most ulcers, but can be helpful when the diagnosis is uncertain.
The most common causes are venous insufficiency, arterial insufficiency, and neuropathy. So they’re often classified as venous, arterial, or neuropathic.
Venous ulcers are associated with venous insufficiency due to valve dysfunction, which causes stasis of blood in the legs, and that leads to an increase in venous pressure. This in turn allows blood proteins and fluid to leak into the interstitial space.
Over time this increases the pressure in the tissues and can cause tiny capillaries to get pinched shut, ultimately leading to tissue ischemia and subsequent breakdown of the tissues - including the skin.
Some risk factors are being older, female, obese, pregnant, and standing for a prolonged period of time.
They’re usually on the lower leg, on the "gaiter" area of the leg, which extends from the mid-calf to ankle, on the medial side of the leg, around the medial malleolus. And they can cause mild to moderate pain.
There may also be stasis dermatitis or lipodermatosclerosis, which is erythematous induration and fibrosis of the lower medial leg, which can also be painful.
If the diagnosis is unclear or if surgical intervention is being considered, then noninvasive venous imaging with duplex ultrasonography can be done to assess reflux and obstruction in the superficial, deep, and perforating veins.
Surgical treatments are used in severe disease, and they include vein transplant, vein repair, or vein removal.
Arterial ulcers, also known as ischemic ulcers, are typically associated with peripheral artery disease, in which the ischemia is due to occlusion of an artery leading to reduced blood flow to the tissue, leading to tissue necrosis and ulceration.
Arterial ulcers often begin as minor wounds that fail to heal because the blood supply doesn’t meet the increased demands of the healing tissue. The lesions are often dry and painful, but with little bleeding.
Arterial ulcers tend to occur on the tips of the toes, or between toes, lateral side of the leg and over bony prominences, such as on 1st or 5th metatarsal head, or pressure areas like the heel, malleoli, and shin.
Peripheral arterial disease can be diagnosed with ankle-brachial index or ABI testing, which measures the ratio of systolic blood pressure in the ankle to the systolic blood pressure in the upper arm.
For treatment, arterial blood flow must be reestablished with revascularization; options include percutaneous intervention, surgical bypass, or a combination of these, followed by closure of the ulcer by primary healing or secondary reconstructive surgery.
There’s often reduced sensitivity to touch, temperature, and pain, and it most often involves the longest nerves, which are in the lower legs and feet.
Feet often get damaged by thermal or mechanical trauma, and the tissue breaks down and can get infected.
Neuropathic ulcers often go unnoticed until they’re pretty advanced, so they often need debridement of nonviable and infected tissue, revisional surgery on the bony architecture, vascular reconstruction, and graft options for soft tissue coverage. Often, amputation of the limb is required.
Now, in addition to venous, arterial, and neuropathic ulcers there are also some less common causes of leg ulcers, such as pressure, infections, pyoderma gangrenosum, skin cancer, and certain medications.
Pressure ulcers, also known as bedsores or decubitus, and they usually occur over a bony prominence on the lower extremity, often at the heel, as a result of pressure applied to soft tissue which causes either a complete or partial obstruction to blood flow.