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ower-extremity wounds and disease often perplex the caregiver due to their chronic nature and their multifaceted etiology. They rarely heal without a comprehensive treatment approach. These wounds are caused by numerous diseases but are generally a result of chronic venous insufficiency, lower-extremity arterial disease, diabetes, and neuropathy. Prior to implementation of treatment strategies, differential assessment is necessary in order to address the etiology and pathogenesis related to each type of lower leg wound. This article will focus on the treatment of venous insufficiency with compression therapy and the treatment of diabetic and neuropathic ulcers with offloading techniques. Want to know more about basic techniques and secrets to healing these chronic lower leg ulcers? Stay tuned for all the answers!

First Things First…The History and Assessment
       Before any compression or offloading is initiated, we must first ascertain the cause of the chronic wound and/or skin condition. Generally, any chronic wound below the pelvis can have a mixed etiology, and usually, blood flow issues are to blame. A detailed medical history and physical exam are the first steps in treating these lower limb maladies. Included in the history should be onset and course of the ulcer, symptoms (including relieving and exacerbating factors), general medical history (i.e., history of any vein surgeries, deep vein thrombosis, etc.), family medical history (i.e., diabetes mellitus), medications, and social history (i.e., job that requires constant standing, obesity, smoking).

Figure 1. Key strategies for management of lower extremity wounds

       The physical history should involve a thorough exam including deep tendon reflexes, peripheral pulses, peripheral neuropathy, noninvasive vascular tests (transcutaneous oxygen measurement and ankle/brachial index), and ulcer characteristics including wound bed, location, and surrounding skin. See Suggested Reading for literature about the physical exam and its components.

Treatment
       Various treatment measures should be implemented according to the ulcer type and etiology (see Figure 1).
       Leg ulcers require management that includes a holistic approach. Although compression therapy and offloading are two cornerstone treatments for lower leg ulcers, it is imperative that systemic diseases, such as diabetes, cardiovascular disease, and other comorbidities, are controlled in order to heal these burdensome wounds.
       Basic wound bed preparation including assessment, cleaning, debriding, treatment of bacterial balance, control of exudate, and maintenance of moisture balance should be accomplished with all chronic wounds, especially the challenging venous and diabetic neuropathic wounds that are frequently problematic. For more information on preparing the wound bed, see Suggested Reading.

Figure 2. Ankle/brachial index values and treatment

Compression
       Leg elevation above heart level for a period of two to four hours a day and at night is a helpful adjuvant therapy, but it is often difficult to get patients to comply. If the diagnosis is venous insufficiency and the ankle/brachial index (ABI) is within the limits for compression (see Figure 2), compression therapy should be instituted.
       Management of venous disease and healing of venous ulceration is best treated by increasing venous return, decreasing venous stasis and resulting edema, supporting the wound topically and holistically, and applying therapeutic vascular compression. Compression therapy is the mainstay of treatment for venous stasis and venous ulcer ailments.[1] Compression therapy involves increasing the external pressure on vascular elements to assist venous fluid return to the heart. By increasing the external pressure, the gastrocnemious muscle and other lower-extremity skeletal muscles have assistance in pushing venous blood upward to the heart in order to be oxygenated. Compression applied to the lower extremities promotes venous blood return, prevents blood pooling, and decreases edema.
       The level of compression provided by a multilayer bandage system can be determined by applying LaPlace’s Law, which states that sub-bandage pressure is determined by the number of layers of bandage applied and the tension at which it is applied. Leg circumference and width of the bandage are also factors that can affect the pressure. The factors influencing the pressure that can be achieved under a bandage are given in the following equation: pressure exerted by the bandage equals the number of layers of bandage multiplied by the bandage tension divided by the circumference of the limb multiplied by the bandage width. As such, as the limb circumference increases, compression decreases (see Figure 3). In other words, a thinner ankle can achieve 30 to 40mmHg with the same bandage that will give only 15 to 20mmHg compression to a larger circumference of the leg (e.g., just below the knee).

Figure 3. Equation for pressure achieved under a bandage

       The most effective way to manage venous disease is to apply graduated compression from the base of the toes to just below the knee. The highest pressure (35–40mmHg) is applied at the ankle and is reduced at least 50 percent at the knee. Methods of achieving graduated compression include the application of single-layer elastic bandaging, single-layer inelastic or support bandaging, medicated wraps, multilayer bandages, compression stocking, multilayer compression stockings, elasticated tubular bandages, and intermittent pneumatic sequential devices.
       Several methods for providing therapeutic compression are available at varying costs and require different levels of skill for proper application. A recent systematic review of 22 randomized, controlled trials (RCTs) revealed that three- and four-layer high-compression bandages increased the percentage of ulcers healed compared to those treated with single-layer compression or paste bandages.[2] The choice of compression should be based on the patient’s needs and abilities. Let’s review the various forms of compression therapy.

Long-Stretch Elastic Bandages
       Long-stretch elastic bandages offer moderate to high levels of compression that are sustained over time, regardless of the patient’s mobility. This is especially useful for immobile patients. This type of bandage often consists of an orthopedic wool underlayer together with the bandage. One advantage to the use of long-stretch elastic bandages is that they are reusable and can be washed (elastic portion only). They can, however, be applied with excessively high pressure if they are overextended during application. It is important to choose bandages that offer symbols to help gauge correct extension. For example, a solid line on the bandage turns to a dashed line or a rectangle turns to a square when the correct amount of compression or stretch is applied. A disadvantage is that these high-compression bandages may lack the ability to conform to limb contours causing slipping. This is especially true with the champagne bottle-shaped legs of a chronic venous ulcer patient and can require constant re-wrapping. The manufacturers’ recommendations should be read carefully before these or any bandages are applied.

Figure 4. Four-layer compression bandaging system

Inelastic or Support Bandages (Short Stretch)
       The effectiveness of inelastic or support bandages increases with patient activity. They have a low resting pressure index, can be utilized with patients with mild arterial disease (mixed etiology), and are nonallergenic and cost effective. They are also washable and reusable. Support bandages are not recommended for the immobile or those with reduced ankle function. They are excellent for patients with thin ankles (<18cm circumference) and edematous feet.

Medicated Wraps
       Medicated wraps, such as the Unna Boot or Duke boot, utilize wet zinc oxide bandages applied in a continuous spiral fashion. The Duke boot incorporates a hydrocolloid wafer over the wound and adds a flexible cohesive outer layer. The second layer of cohesive bandages helps prevent slipping.
       These dressings tend to be bulky, hot, and sometimes uncomfortable for the wearer. They are intended for single use only but can remain in place for up to four to seven days, which can reduce the number of follow-up visits or dressing changes, making them cost effective. Patients with loss of muscle tone and friable, fragile skin may not be able to tolerate multilayer bandage systems due to the high pressure of the bandages, which may cause new areas of breakdown. Another pitfall of medicated wraps is that they are not effective unless the patient is ambulatory nor do they adjust and maintain compression as edema reduces.

Figure 5. Spiral and figure-eight wrapping techniques. Courtesy of Medline Industries, Inc., Mundelein, Illinois.

Multilayer Bandages
       Multilayer bandages are easy to apply, and high levels of pressure can be maintained over a long period of time. These compression bandage systems offer a seven-day change frequency, making them cost effective. They utilize three or four separate layers depending on the system (see Figure 4).
       With a traditional four-layer compression system, the first layer is a light nonwoven padding material that absorbs exudate and protects bony prominences. The second layer adds absorbency and smoothes the first layer, preserving the elastic energy of the compression layer. The third layer provides light compression and is highly conformable to accommodate difficult limb shapes. The fourth layer applies compression and maintains the system in place for a full week. The first, second, and fourth layers are applied using a simple spiral technique, while the third or compression layer is applied using a figure-eight technique (see Figure 5).
       The four-layer bandaging system provides approximately 30–40mmHg pressure at the ankle, decreasing to 12–17mmHg at the calf. It is best suited for ankle circumferences greater than 18cm or 7 inches. If necessary, the ankle can be padded to achieve the desired circumference. These methods can be bulky but are usually comfortable. Like the medicated wraps, they cannot get wet, so hygiene can be an issue. Pre-packaged kits take the guesswork out of gathering appropriate supplies and save valuable nursing time. Examples include Profore (Smith & Nephew, Largo, Florida) and FourFlex (Medline Industries, Inc., Mundelein, Illinois).

Figure 6. Multilayer class 3 stocking compression system

Multilayer Class 3 Stocking Compression System
       These newer stocking systems provide controlled graduated compression (40–50mmHg) made from a specially designed understocking and overstocking that deliver the same compression as a multilayer bandaging system. They are attractive (see Figure 6), and patients are free to remove them for bathing or dressing change at any frequency, increasing compliance. They also tend to be gentle to the skin, reducing irritation. A recent study showed that over a 12-week treatment period, 14 percent of patients with venous ulcers healed with a traditional bandaging system, while 46 percent of patients healed with the multilayer class 3 compression system.[3] An example is the Multi-Layer Stocking System by Carolon Company (Rural Hall, North Carolina).

Elastic Compression Stockings
       Elastic compression stockings are used for prevention once healing of ulcers has occurred. These stockings must be worn continuously whenever the patient in not recumbent and at rest. They are available in several configurations including knee highs, thigh highs, and panty hose with different variations, such as open-toed, closed-toed, and zippered varieties in many fashionable colors. Elastic compression hose available today are attractive and do not appear overtly “medical,” which increases overall compliance.
       The strength of compression hose prescribed depends on the ankle/brachial index (ABI) and the observed symptomatology. Patients with conspicuous veins and no apparent edema require very light compression of 8mmHg to 15mmHg to light compression of 15mmHg to 20mmHg. When edema and leaky venules (brown staining of the skin or hemosiderin changes) arise, class 1 or 20mmHg to 30mmHg of pressure is needed. With the development of lipodermatosclerosis and fibrin escape, class 2 or 30mmHg to 40mmHg of pressure is needed. If the patient develops lymphedema, a class 3 or compression greater than 40mmHg is necessary.

Figure 7. Example of a total contact cast

       Higher compression hosiery can often be difficult to apply. The clinician should be aware of the various assistive devices available to help patients don their stockings and increase compliance. Bariatric patients or patients with lymphedematous limbs may use a Velcro-tabbed boot-like stocking, such as CircAid® Thera-Boot™ Compression System by Coloplast Corporation (Marietta, Georgia). Contact your compression therapy supplier for specific tools as well as patient education pieces, such as pamphlets and videos.
       Compression stockings should not be confused with antiembolism stockings, or T.E.D. hose, that should only be used for prevention of deep vein thrombosis in patients who are on bed rest. They only offer 18mmHg at the ankle, which is not enough compression for clients with venous disease.

Elasticated Tubular Bandages
       These practical, versatile, self-retaining elasticated support bandages come on a roll and can be cut to fit a particular body part. They provide support following soft tissue injuries, dislocation, and sprains. They are constructed of knitted fabric with interwoven elastomer and are an excellent choice when radial support is required. These bandages are suitable for a wide variety of clinical applications, such as hypertrophic scarring, support for amputation stumps, reduction of edema, assisting venous return, and prevention of varicose veins. They come in a variety of sizes and are easy to use and apply quickly. These unique compression devices are typically applied using two layers and provide approximately 7mmHg per single layer, depending on the body area and limb circumference. Examples include Tubigrip (ConvaTec, a Bristol-Myers Squibb Co., Princeton, New Jersey) and Medigrip (Medline Industries, Inc.).

Figure 8. Removable walking boot

Pneumatic Compression Devices
       Pneumatic compression devices involve the application of a controlled external pressure cycle using compressed air, which intermittently inflates a specially designed garment fitted to the upper or lower limb. This therapy has been shown to aid venous return, reduce edema, stimulate fibrinolysis, and heal incalcitrant ulcers after other methods have failed. Compression stocking are often used when pneumatic devices are not in use.

Reimbursement for Compression Stockings
       Effective October 1, 2003, gradient compression stockings may be covered when the beneficiary has an open venous stasis ulcer that has been treated by a physician or other healthcare professional requiring medically necessary debridement and when the gradient stocking can be proven to deliver compression greater than 30mmHg and less than 50mmHg.

Compression for Life
       Long-term management and prevention of ulceration can be a challenge for the patient and the clinician. The reoccurrence rate of venous ulcers is as high as 70 percent.[4] Once the acute phase of venous ulcer care is complete, the patient must wear some type of compression hose or wrap for the rest of his or her life. Stockings must be replaced regularly, approximately every 6 to 12 months or as recommended by the manufacturer, since they loose elasticity and do not function as well over time.

Figure 9. Healing sandal

Offloading
       When caring for patients with various foot ulcers, particularly diabetic/neuropathic wounds, offloading to redistribute pressure from the site is essential. The goal is to offload pressure and relieve shear and friction at the ulcer site while keeping the patient ambulatory. Offloading is described as “any measure to eliminate abnormal pressure points to promote healing or to prevent recurrence of diabetic foot ulcers.”[5] Although crucial to the healing of a neuropathic ulcer, offloading is often neglected.
       Most noninfected, neuropathic foot ulcers heal when pressure is removed, but if high plantar pressures continue, healing will not occur. Prescription shoes and custom-fitted orthotics have been reported to be more effective than regular shoes in reducing the occurrence and reoccurrence of ulcers.[6] A variety of orthotic devices are available to offload plantar pressures including total contact casting, custom-fabricated posterior walking splints, and specialized half-shoes with metatarsal bars. Other methods of offloading include bed rest and wheelchair and crutch use. The literature reports the highest percentage of healed ulcers using total contact casting, with as high as 90 to 100 percent success.[7,8] Another study showed 96 percent healed with a mean healing rate of 70 days with a half-shoe.[9] It is imperative that the offloading strategy implemented match the age, activity level, strength, and social situation of each individual. Education of the cause and treatment for both the patient and family is critical for compliance and healing. In some cases, offloading is not enough, and surgery may be needed to correct foot deformities.

Total Contact Casting
       Total contact casting (TCC) (see Figure 7) is considered the gold standard for offloading the diabetic/neuropathic foot. Much like casting a fracture, TCC provides the same protection, rest, and immobilization, reducing the patient’s activity and allowing the ulcer(s) to heal.
       A modification of a traditional fracture cast, the TCC has less cast padding and completely covers the toes for protection. Other components of the TCC in order of application include padding (usually foam), plaster shell reinforced by plaster splints, a walking heel for ambulation, and fiberglass reinforcements.
       The foot and leg are rendered motionless, since the cast is molded exactly to their contours, offloading the foot constantly. A trained and skilled clinician must apply the cast, which needs to be changed about every one to two weeks. Advantages of using TCC is that it reduces pressure while allowing the patient to remain ambulatory and is one of the most effective ways to treat plantar diabetic/neuropathic foot ulcers in an average of six to eight weeks. A disadvantage is discomfort of the cast, which can be hot, heavy, and difficult to maneuver.
       Although it is the most effective treatment for offloading neuropathic foot ulcers, TCC should never be used with an infected or suspected infected ulcer because of the inability to view the wound site and to provide treatment. Options for offloading in patients with infected neuropathic ulcers include the orthotic dynamic system splint (ODS) and the neuropathic walker. Both are removable alternatives to TCC, allowing daily assessment and treatment.
       Easy-to-use and inexpensive, removable walking boots provide a convenient offloading technique to protect and heal neuropathic wounds. No special training is necessary in order to properly apply or remove these boots, and they can easily be removed to care for the wound(s). Compliance is sometimes a challenge, since patients can easily remove them. Examples include the PneumaticWalker™ by AirCast® (Summit, New Jersey), the Bledsoe Conformer Diabetic Boot (Bledsoe Brace Systems, Grand Prairie, Texas), and the DH Walker by Royce Medical Co. (Camarillo, California). See Figure 8 for an example of a removable walking boot.

Half-Shoes, Wedges, and Healing Sandals
       Useful for patients who need frequent monitoring of their ulcer(s), who can’t tolerate TCC, or who just completed TCC therapy and are awaiting their therapy shoes, half-shoes, wedges, and sandals provide effective offloading to the forefoot and come in a variety of shapes, sizes, and configurations. Examples include the DH Shoe by Royce Medical Co. and the OrthoWedge™ Healing Shoe by Darco (Huntington, West Virginia). See Figure 9 for an example of a healing sandal.

Orthotics
       Both off-the-shelf and custom-made foot and ankle orthoses can be used for diabetic/neuropathic ulcers, Charcot foot deformities, and other lower-extremity pathology. Custom orthotics are typically constructed of Plastazote and Poron, rigid materials that provide relief from pressure, shear, and friction while providing shock absorption and accommodation of foot deformities. These custom made devices can be very expensive, costing around $1,000. A number of off-the-shelf devices are now available and are much less expensive and, thus, more widely used. These devices must be replaced at regular intervals, since the materials in the insoles break down and loose effectiveness over time.

Custom Shoes
       Patients with foot deformities or special support needs may benefit from custom diabetic shoes. They are considered a preventative modality and a first line of defense against development of a neuropathic foot ulcer. These shoes can offer basic offloading, extra depth or width, or other custom features based on the patient’s needs. Medicare B now covers the purchase of custom shoes when the certifying physician identifies a risk factor for ulcer formation and submits appropriate documentation.

Reimbursement for Diabetic Shoes and Orthoses
       The Medicare Therapeutic Shoe Bill of 1993 provides financial support for one pair of appropriate inlay-depth shoes and three pairs of custom foot orthoses yearly for individuals with diabetes. Most insurance carriers have followed their lead with similar guidelines. They have realized that preventive strategies are cost effective compared with complicated wounds and potential amputation. A certified pedorthist is essential in developing the correct and perfectly fitting prescription. The shoe bill requires that both the physician treating the diabetes and the orthopedic surgeon or podiatrist treating the foot sign the prescription.

Key Mechanisms to Proper Treatment
       Without properly applied compression for venous stasis and venous ulcers and offloading for diabetic/neuropathic ulcers, our treatment plan falls flat. Both treatments are pivotal to healing and overall success of the care plan. Make sure your strategy includes prudent choice of the correct topical dressings beneath these therapies. Many venous and neuropathic wounds are critically colonized and have a heavy bioburden that halts healing. Consider the use of novel dressings with ionic silver components under both compression and offloading modalities. Most dressing categories are now available with ionic silver. Examples include silver amorphous hydrogels, sheet hydrogels and strands, powders, films, hydrofibers, foams, fabrics, and hydrocolloids. Many of these are able to effectively stay in place and offer broad-spectrum antimicrobial action for up to seven days and can be matched to the wound’s unique needs and exudate levels. Highly conformable dressings for hard-to-dress wounds, such as between toes, can be addressed with unique dressings like ionic silver powders and amorphous hydrogels. In order to have the best possible outcomes, match the dressing to the wound’s needs.
       You are now armed with the secrets to healing difficult-to-handle lower leg chronic wounds—go forth and conquer!

Suggested Reading
1. Fleck C. Getting off on the right foot: Uncovering the mystery of caring for skin and wounds in the patient with diabetes. Extended Care Product News Jan-Feb 2004;91:12–9.
2. Fleck C. Putting the squeeze on: Understanding venous disease and compression therapy. Extended Care Product News Mar-Apr 2002;80:4–9.
3. Fleck C. Wound bed preparation: The good, the bad, and the ugly. Extended Care Product News Mar-Apr 2003;86:24–7.