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Venous ulcers - Introduction and Assessment

Venous ulcers - Introduction and Assessment

Venous ulcers - Introduction and Assessment

ABSTRACT

Venous Leg Ulcers (VLU) are relatively common, affecting 1% of the population in the U.S.[1] VLU can be defined as an open skin lesion of the leg or foot that occurs in an area affected by venous hypertension, often caused by chronic venous insufficiency.[2] It is a chronic condition, with recurrence rate within 3 months after wound closure as high as 70%.[1] Thirty-five percent of people with VLU experience four or more episodes.[3][4]

For VLU management including a section for clinicians on patient education, see "Venous ulcers - Treatment and Prevention". For clinical guidelines and quality measures specific to VLU, see "Venous Ulcers - Overview".

Assessment: See Algorithm for Assessment of Venous Ulcers 

History: A complete assessment of the patient, performed by a qualified multidisciplinary team, includes identification of risk factors for chronic venous insufficiency (CVI), development of VLU, VLU recurrence and delayed healing. Patient's concerns and psychosocial status should also be assessed.

Physical ExaminationSigns of chronic venous disease include active or healed ulcers, varicosities, telangiectasia, varicose veins, edema, etc. VLUs generally develop in the gaiter area, between mid-calf and approximately 1 inch below the malleolus [5]. VLUs can be superficial to deep and generally have irregular margins, wound bed with fibrin and granulation tissue, and moderate to heavy exudate. 

Diagnosis: Predominantly clinical, but peripheral arterial disease (PAD) needs to be ruled out with evaluation of ankle brachial index (ABI) ratio, audible handheld Doppler ultrasound with continuous waveform analysis or other noninvasive arterial tests. An ABI <0.9 indicates an ischemic component. Venous disease is objectively documented with duplex ultrasound. Other tests can be ordered when necessary

Differential diagnosis: Arterial ulcers, neuropathic ulcers, pressure ulcers are among the most common differential diagnoses.

Characterization of VLUs: After differential diagnoses are ruled out and etiology is established, expert consensus recommends categorizing VLUs as "simple", "complex" or of "mixed etiology" to determine likely prognosis, so that appropriate timeframes for monitoring, reassessment and specialist referral can be established [6]

Ulcer healability: Classification according to potential to heal with conservative management only is helpful in determining an adequate treatment plan. Ulcers that can be healed with conservative management only are categorized as "healable", ulcers that are likely not going to heal with conservative management only are "non-healable" and if co-existing medical conditions, drugs or circumstances will likely impede wound healing, ulcers are classified as "maintenance". See topic "How to Determine Healability of a Chronic Wound"

Documentation: To be done at least weekly to assess wound healing progress. Proper documentation includes number and position of ulcers on the leg, wound measurements including area, perimeter, and depth, description of wound edge, peri-wound area, wound base quality, amount and type of drainage, and infection, history of debridement. Signs of VLU improvement need to be documented to support medical necessity (as per Medicare requirements). As part of a patient-centered approach, it is recommended that clinicians adopt patient-reported outcome measures to assess patient’s Quality of Life (QOL), pain, and depression. [7]

    Treatment: see "Venous ulcers - Treatment and Prevention" 

    Patient Education: see "Venous ulcers - Treatment and Prevention" 

    When to refer to specialists: 

    • Specialized service/clinic that manages VLU (e.g., wound clinic), if initially treated elsewhere: "Complex" VLUs and "mixed etiology" leg ulcers, atypical presentation, pressure ulcer/injury. To facilitate referral and transition of care, use the "Provider Wound Communication Tool"
    • Vascular surgeon: Abnormal ankle brachial index ratio, duplex ultrasound results with any indications for vascular surgery, peripheral artery disease, critical limb ischemia
    • Emergency department: Acute limb ischemia, sepsis, necrotising fasciitis
    • Nutritionist at initial evaluation
    • Respective specialists if associated dermatological, metabolic, hematologic, autoimmune, oncologic diseases are suspected
    • Plastic surgeon for surgical wound coverage procedures
    • See details in Table "Pressure levels and management of simple, complex and mixed VLU' in topic "Venous Ulcers - Treatment and Prevention"

    ICD-10 Coding

    First select ICD-10 for underlying pathology:

    • Chronic venous hypertension with ulcer (I87.31-, I87.33-)
    • Post-phlebitic syndrome with ulcer (I87.01-, I87.03-)
    • Post-thrombotic syndrome with ulcer (I87.01-, I87.03-)
    • Varicose ulcer (I83.0-, I.83.2-)

    Then for VLU severity:

    • Non-pressure chronic ulcer of the calf (L.97.2-)

    Clinical guidelines and Quality Measures: see "Venous Ulcers - Overview"

        Algorithm for Assessment of Venous Ulcer |  First Visit Checklist |  Follow up Visit Checklist

      INTRODUCTION

      Overview

      This topic covers the Introduction and Assessment of venous leg ulcers (VLU) including epidemiology, risk factors, etiology, pathophysiology, history,  physical examination, diagnosis, differential diagnoses, documentation and ICD-10 coding. For VLU management including a section for clinicians on patient education, see "Venous ulcers - Treatment and Prevention". For clinical guidelines and quality measures specific to VLU, see "Venous Ulcers - Overview".

      Background

      Venous disease is a chronic condition that can be characterized by periods of ulceration (i.e. an open wound) followed by healing and then recurrence.[8] Venous Leg Ulcers (VLUs) are a relatively common, complex type of wound that have a negative impact on people’s lives and incur high costs for health services.[9] 

      • Definition: VLU can be defined as an open skin lesion of the leg or foot that occurs in an area affected by venous hypertension.[2] VLUs can result in pain, unpleasant odor, reduced mobility, sleep disturbance, reduced psychological well-being and social isolation.[9] In severe cases and when associated with arterial insufficiency, VLUs can lead to limb amputation.[10][11]
      • Relevance of VLUs:
        • Venous ulcers are often recurrent:
          • The recurrence rate within 3 months after wound closure is as high as 70%.[1] Thirty-five percent of people with VLU experience four or more episodes during their life times.[3][4]
        • Open ulcers can persist from weeks to many years:
          • The first-line treatment for VLUs is compression therapy, but despite adequate compression up to 45% of people have unhealed ulcers after 6 months of treatment.[9][12] Since these figures were extracted from randomized controlled trials, the percentage of unhealed ulcers in the real world are probably higher.
          • It is estimated that 93% of VLUs will heal in 12 months, and 7% remain unhealed after five years. 
        • Despite the relatively low prevalence, VLUs represent a significant financial burden to the healthcare system:
          • In the U.S., the overall burden to Medicare and private insurers due to VLU is estimated to be around US$14.9 billion (in 2012 US$, excluding out-of-pocket payments and other indirect costs such as lost productivity).[13]
          • In the U.K., estimated costs to treat a person with open leg ulcer is around GBP 1700 (US$ 2122) per year at 2012 prices, mostly related to nurses' time.[14] 

      Epidemiology

      Prevalence

      • Prevalence of ulcers of venous etiology only the UK is about 2.9 cases per 10,000 people [9][15], whereas mixed arterial/venous leg ulcers have a prevalence of 1.1 per 10,000 people.[2]
      • Approximately 1% of the population in the United States, 3% of people over 80 years of age in westernized countries. [1] Prevalence is increasing, coinciding with an aging population. In the U.S., VLUs affect between 500,000 to 2 million people per year. [16]
      • More prevalent among women, but this gender discrepancy decreases with age. [17]
      • Most common type of leg ulcer (~ 80% of  leg ulcers). [18]

      Incidence

      • The overall incidence rate is 0.76 (95% CI, 0.71, 0.83) for men and 1.42 (1.35, 1.48) per 100 person-years for women. [19]

      Risk Factors   

      • Risk factors for development of VLU:
        • Presence of chronic venous insufficiency (CVI): risk factors for CVI include older age, obesity, previous leg injuries, deep venous thrombosis, phlebitis, low physical activity, prolonged standing or sitting, arterial hypertension, deep venous thrombosis, family history of VLU.[20][18][17] [21]
        • Genetic predisposition to early onset of varicose veins: Klippel-Trenaunay syndrome, CADASIL, FOXC2 gene mutation, desmulin dysregulation, and Ehlers-Danlos syndrome [21]
      • Risk factors for delayed VLU healing:
        • Initial VLU location, area and duration are the most important predictors [22]: 
          • VLU location in posterior ankle or back of calf region [7]
          • VLU that is smaller than 10 cm2 and has a duration shorter than 12 months at first visit has a 70% change of healing by the 24th week of care, whereas a VLU larger than 10 cm2 and with a duration longer than 12 months has only 22% chance of healing by the 24th week of care [9][23].
        • Other risk factors include [7]:
          • > 50 years, male gender
          • History of vascular surgery, trauma, repeat intimal venous damage or varicosities
          • Family history of VLU
          • BMI > 33 kg/m2 with documented nutritional deficiency
          • Multiple pregnancy
      • Risk factors for recurrence [7]:
        • Deep venous thrombosis
        • Thrombophilia 

      Etiology

      VLUs are the final stage of chronic venous insufficiency (CVI) and associated venous hypertension (increased ambulatory venous pressure).[21][9] 

      • The term chronic venous disease is generally applied to the full spectrum of chronic venous disease (CEAP C0-6), whereas chronic venous insufficiency is reserved for more severe presentations (CEAP C4-6). [24]
      • It is not infrequent for leg ulcers to be associated with CVI and arterial vascular disease, in which case, these ulcers are said to be of “mixed etiology.”

      Pathophysiology

      • CVI results in venous hypertension (ambulatory venous pressures of up to 60 to 90 mmHg, as opposed to the normal levels of 20 to 30 mmHg), which can happen due to obstruction to venous flow or venous reflux from dysfunction of venous valves, and/or failure of the "venous pump".[21][25] Reflux is much more prevalent among patients across the different stages of CVD, including VLUs. However, obstruction has a higher rate of patients who develop VLU and a much faster disease progression.[21]
      • Venous hypertension and hemodynamic abnormalities lead to inflammatory alterations with microcirculatory changes that can result in venous stasis and VLU.[25]
      • The pathophysiology of VLU is complex and healing is delayed in many patients due to a chronic inflammatory condition.[26] Patient risk factors predispose individuals to chronic venous diseases including VLU. Changes in shear stress to the vein walls are likely initiating events, leading to activation of adhesion molecules on endothelial cells, and leukocyte activation with attachment and migration into vein wall, microcirculation, and in the interstitial space. Multiple chemokines, cytokines, growth factors, proteases and matrix metalloproteinases are produced. The pathology of VLU involves an imbalance of inflammation, inflammatory modulators, oxidative stress, and proteinase activity.[26][21]

        ASSESSMENT

        • Primary goals of assessment are:
          • To identify risk factors for VLU, amputation, delayed healing, recurrence. See details in “Risk Factors”
          • To assess patient's and caregiver's concerns
          • To screen for significant signs and symptoms to differentiate from other types of lower extremity ulcers, which may require different treatments. See “Differential Diagnoses”
          • To categorize VLUs as "simple", "complex" or of mixed etiology (i.e., due to venous disease and peripheral arterial disease) to determine likely prognosis, so that appropriate time frames for monitoring, reassessment and specialist referral can be established [6]
            • Peripheral arterial disease (PAD) needs to be ruled out with noninvasive arterial tests and venous disease should be documented with duplex ultrasound. See section 'Diagnosis' below 
          • To determine "healability", that is, the potential of the ulcer to heal with conservative treatment only
          • See Algorithm for Assessment of Venous Ulcers below (Algorithm 1)

          Algorithm 1. Algorithm for Assessment of New and Recurrent Venous Ulcer (click link to enlarge)

          History

            Qualified professional multidisciplinary team should evaluate and perform a complete assessment of the patient. Patients with VLU frequently present with other co-morbidities that may impede healing. It is important to obtain a comprehensive patient history of the patient’s current condition, recurrence and treatment if any, medical and surgical history including past deep vein thrombosis (DVT), pulmonary embolism or malignancy, medications, and other risk factors related to VLU, CVI or non-healing leg wounds.[2][27][28]

            Chief Complaint and History of Present Illness

            • Time of symptom onset and duration
            • Symptoms experienced by patients with VLU include extremity pain, burning aching, throbbing, cramps, heaviness, itching, tiredness, fatigue, and restless legs.[2][18][27] Venous symptoms are usually exacerbated when the patient is standing and relieved by rest or limb elevation (as opposed to pain of peripheral artery disease, which worsens with walking or that is relieved by rest, or which worsens with limb elevation). Pain is localized to the affected veins, skin changes or ulcer and does not irradiate.
            • Edema of lower extremities:
              • History of medical condition resulting in edema of lower extremities, such as heart failure, hypothyroidism, hypoalbuminemia or nephrotic syndrome
              • History of lymphatic disease resulting in edema of lower extremities. It is common for chronic venous disease to be associated with chronic lymphatic insufficiency, a condition known as phlebolymphedema. See topic "Lymphedema - Introduction and Assessment".
              • Extremity swelling due to chronic venous disease can be present in 25-75% of patients, worsens with prolonged standing and improves with leg elevation and walking. In women, symptoms exacerbate with menses or pregnancy.  
            • History of complications, such as DVT, embolisms, skin infections, cellulitis, osteomyelitis, and malignant change.[18]
            • Assess risk factors for development of VLU. See section ‘Risk factors’ above 
            • Past treatment history
            • Comorbidities: autoimmune disorders, diabetes, immunosuppression and other conditions may delay healing.[29] 

            Medications

            • Medications that delay wound healing (in case patient has an ulcer) include: anticoagulants, antimicrobials (various antibiotic classes), anti-angiogenesis agents (eg, bevacizumab, aflibercept), antineoplastic drugs, anti-rheumatoid drugs (eg, methotrexate, aspirin/nonsteroidal anti-inflammatory drugs [NSAIDs]), colchicine (anti-gout drug), topical hydrogen peroxide, topical iodine, full-strength 0.5% Dakin’s solution (sodium hypochlorite), nicotine, steroids, and vasoconstrictors.[30][31]

            Social History

            • Injectable drugs: repeated injections of illicit or not illicit drugs into the lower limb veins results in CVI. Increased risk for VLU persists even after prolonged periods free from injecting.[29][32] 

            Nutrition

            • Clinical guidelines recommend nutritional assessment for patients with VLU [2][33][34], despite the relative low number of studies on nutritional supplementation on VLU healing. Poor nutrition may be a risk factor for delayed VLU healing.[35] Patients with VLUs are commonly overweight and also have a relative nutritional deficiency that needs to be addressed.[5][36] 
              • Standardized tools such as the "Nestlé MNA" and "Self-MNA®" by Nestlé can be used
              •  Medicare Quality Payment Program, Quality Measure:
                • "Process Measure: Nutritional Screening and Intervention Plan in Patients with Chronic Wounds and Ulcers" 
                • "Patient Reported Nutritional Assessment and Intervention Plan in Patients with Wounds and Ulcers"
                • "Preventative Care and Screening: Body Mass Index (BMI) Screening and Follow-Up"

            Patient's and caregivers' concerns 

            • Patient's and caregiver's concerns and psychosocial aspects should be assessed and taken in consideration when creating a treatment plan:
              • Evaluate patient's concerns: pain, exudate, odor, ability to carry out daily activities
                •  Medicare Quality Payment Program, Quality Measure: "Pain Assessment and Follow-Up"
              • Evaluate psychosocial aspects of the patient, caregiver and family: cognitive, functional, emotional status, understanding of the wound and risk factors, preference for treatment, motivation for adherence to the care plan, financial concerns
              • We recommend use of Patient-Reported Outcome Tools to assess aspects above and measure impact of interventions. See 'Patient-reported outcomes (PRO) tools' below.

            Physical Examination

            VLUs commonly present in between area mid-calf and approximately 1 inch below the malleolus.[5] The recurrence of an ulcer in the same area is highly suggestive of venous ulcer.[18] Physical examination of lower extremities should include [2]:

              • Inspection (Figures 1-9):
                • Limb shape and size (abnormal shape or large limbs can lead to challenges in compression therapy)
                • Presence of active or healed ulcers, varicosities, telangiectasia, varicose veins, edema
                • Chronic venous skin changes and dermatitis, such as skin discoloration, inflammation, eczema, hyperpigmentation, malleolar flair, corona phlebectatica (venous starburst of veins radiating distally from the medial malleolus), atrophie blanche (capillaries are virtually absent in areas of fibrotic scars, also known as livedoid vasculopathy), lipodermatosclerosis (severe fibrosing panniculitis of the subcutaneous tissue, area of indurated inflammatory tissue that binds the skin down to the subcutaneous tissue)
                • Signs of infection, cellulitis
              • Palpation: varicosity, palpable venous cord, tenderness, sensation, induration, edema, and pulses
              • Auscultation: bruit and reflux
              • Evaluation of ankle mobility
              • Assessment of foot temperature, measurement of the ankle brachial pressure index, testing for peripheral neuropathy, to look for signs of associated diseases such as arterial disease or diabetes mellitus.[5]                

              Figure 1. Atrophie blanche and livedoid vasculopathy

                Ulcer Exam

                • Wound assessment: location, number and size of ulcers, edges, undermining, presence and type of nonviable tissue, signs of infection or biofilm, exudate type and quantity, periwound appearance (e.g., altered perfusion, maceration), edema.[29][37] 
                • Common VLU characteristics: 
                  • Anatomic location: often at the medial distal lower extremity and ankle, at the malleolar area
                  • Margins: irregular 
                  • Depth: superficial-to-deep
                  • Wound bed: granulation tissue and fibrin often present, minimal to moderate aching pain at borders and middle of the wound bed
                  • Exudate: frequent, moderate to heavy. 
                    • "Wet leg syndrome": occurs when large quantities of exudate exude from lower extremities, increasing risk for skin maceration, infection and wound chronicity.[29] Often seen in phlebolymphedema. See topic "Lymphedema - Introduction and Assessment".

                Figure 2. Venous ulcer and stasis
                dermatitis on right lower leg

                Figure 3. Superficial venous ulcer
                with irregular margins   

                Figure 4. Venous ulcers on right and left lower extremities


                Figure 5. Venous ulcer: indurated margins,
                red granulation tissue 

                Figure 6. Highly exudative venous ulcer
                with fibrin tissue

                Figure 7. Venous stasis

                Figure 8. Refractory VLU (<30% decrease in size after 4 weeks of care)

                Figure 9. Legs with abnormal shape (inverted champaigne bottle) and venous stasis


                Diagnosis

                The diagnosis of VLU is predominantly clinical, however peripheral arterial disease (PAD) needs to be ruled out and venous disease should be documented with duplex ultrasound. PAD can be present in up to 25% of VLU patients [3][4] and may be ruled out with evaluation of ankle brachial index ratio (ABI) or audible handheld Doppler ultrasound with continuous waveform analysis. Other tests can be ordered when necessary. See section on 'Algorithms' in topic "How to Select Adequate Compression Therapy Pressure Levels and Products"See different noninvasive arterial testing devices in topic "Assessment and Documentation". 

                •  Medicare Quality Payment Program, Quality Measure: "Noninvasive Arterial Assessment of patients with lower extremity wounds or ulcers for determination of healing potential"
                • Ankle Brachial index (ABI) ratio for patients with lower extremity ulcer, no diabetes and no arterial calcification (See Table 1).
                  • ABI testing can be completed with a hand-held Doppler machine and sphygmomanometer, or an automated ABI device.
                  • Medicare will cover ABI and other noninvasive arterial testing if specific criteria are met.[38] 
                • Audible handheld Doppler ultrasound with continuous waveform analysis, toe pressure, transcutaneous oxygen pressure (TCOM, TcPO2) are preferable for patients with diabetes or arterial calcification (See Table 1)
                  • Clinicians can measure toe pressure by placing a small toe cuff around the great toe and attaching a plethysmography probe at the pulp of great toe tip. The cut-off values of toe pressure and toe brachial index (TBI) are arbitrary and vary in the literature. A toe pressure lower than 30 mmHg or TBI 0.2-0.25 is considered severely ischemic and diagnostic of critical limb ischemia (CLI). Wound healing potential drops as TBI decreases from the normal values.[39]
                  • Microcirculation assessment  prior to primary therapy in patients can be used when concomitant arterial etiology is suspected, if arterial calcification or diabetes, or for monitoring of advanced wound therapy.[2]
                    • TCOM near VLU: if >= 30mmHg, rules out severe arterial disease and predicts VLU healing.[27]

                Table 1. Arterial noninvasive bedside tests and likely interpretation

                For compression therapy according to interpretation of arterial noninvasive tests, see algorithms 'Based on ankle brachial index (ABI)' or 'Based on audible handheld Doppler ultrasound or continuous waveform analysis', and section 'Compression Therapy' in topic "Venous Ulcers - Treatment and Prevention"

                ABI: ankle brachial pressure, AP: ankle systolic pressure, TP: toe systolic pressure, TcPO2 or TCOM: transcutaneous oxygen pressure, TBI: toe brachial index, SPP: skin perfusion pressure.( * ) ABI, toe pressure, TBI values are frequently falsely elevated in patients with diabetes. Patients with diabetes should have TP measurements [40][41]. If arterial calcification precludes reliable ABI or TP measurements, or if ABI is non-compressible (>1.3), ischemia should be documented by TcPO2, SPP, or Doppler continuous waveform analysis [40][42]. (**) Biphasic waveform may be normal in older individuals or when there is no clear transition from triphasic signal along the vascular tree .

                • Comprehensive venous duplex ultrasound for all patients with suspected VLU [5][2][28]:
                  • Rationale: For a leg ulcer to be classified as a VLU, objective documented evidence of venous disease is needed.[2] The correct method/type of ultrasound should be ordered to decrease chances of inconclusive results. Evaluation for both obstructive and reflux patterns of venous disease with comprehensive color flow venous duplex ultrasound including B-mode gray-scale imaging, pulsed Doppler sampling, and color flow analysis, in supine and standing positions is considered first-line [5][2].
                    • Common findings in limbs with VLU are venous reflux (superficial and/or deep) and outward flow in perforators  [46].
                    • Referral to vascular surgeon is recommended in cases with significant superficial junctional venous reflux (saphenofemoral or saphenopopliteal junction reflux >0.5 s) [28] or superficial reflux directed to the ulcer bed [2], deep vein incompetence/obstruction  [2] [28], or perforator incompetence (outward flow of >500 ms duration, with a diameter of >3.5mm located beneath or associated with the ulcer bed) [2][28] or past history of venous surgery [28] 
                • Venous plethysmography for routine initial evaluation of VLU is discouraged unless results of venous duplex ultrasound are inconclusive, or if patient has recurrent or recalcitrant VLU [2].
                  • Rationale: Plethysmography can identify hemodynamic obstruction patterns. If venous refill time measured with below-knee tourniquet and photoplethysmography is greater than 20 mmHg after vein surgery, there is good chance of VLU healing and non-recurrence  [27].  
                • Laboratory evaluation for thrombophilia for patients with a history of recurrent or recalcitrant VLU or thrombosis: these patients have a higher prevalence of thrombophilia, which is associated with recurrent and recalcitrant ulcers [2]. Laboratory evaluation includes [2]:
                  • Inherited hypercoagulable factors (anti- thrombin deficiency, protein C and protein S deficiencies)
                  • Factor V Leiden (resulting in activated protein C resistance)
                  • Prothrombin G20210A
                  • Plasminogen activator inhibitor type 1 mutations
                  • Hyperhomocysteinemia,
                  • Antiphospholipid antibodies (anticardiolipin and lupus anticoagulant),
                  • Cryoglobulins and cryoagglutinins   
                  • Factor VIII related antigen, von Willerbrand factor (VWF), D-dimer and factor V Leiden: if indicative of hypercoagulation tendency, pose a risk factor for post-thrombotic syndrome  [27].
                • Routine wound culture is not advised. Instead, guidelines suggest wound culture only when VLU shows clinical signs of infection.
                • Wound biopsy is indicated in VLU that fail standard therapy after 4 weeks of treatment or for differentiation of other possible non-venous causes for leg ulcer [5][2]. 

                Differential Diagnosis

                • Arterial ulcers: typically painful, and punched out or stellate in appearance. The surrounding skin is red and taut. Some arterial ulcers are pale; others may have a black or yellow eschar.
                • Neuropathic ulcers: Usually occurs on plantar aspect of feet in patients with diabetes, neurologic disorders, or Hansen disease. The extremity and the ulcer are usually insensitive.
                • Pressure ulcer/injury: usually located over bony prominences; risk factors include excessive moisture and altered mental status
                • Metabolic: e.g., diabetes mellitus, gout, Gaucher disease, etc
                • Hematologic: e.g., Sickle cell anemia, thalassemia, polycythemia vera, leucemia
                • Autoimmune: e.g. Rheumatoid arthritis, leukocytoclastic vasculitis, polyarteritis nodosa
                • Exogenous
                • Neoplasia
                • Infection
                • Medication
                • Skin disorders: e.g., Pyoderma gangrenosum, necrobiosis lipoidica, sarcoidosis, acute contact dermatitis

                Characterization of VLUs

                After differential diagnoses are ruled out and etiology is established, expert consensus recommends categorizing VLUs as "simple", "complex" or of mixed etiology to determine likely prognosis, so that appropriate time frames for monitoring, reassessment and specialist referral can be established [6]:

                • Simple VLU
                  • Area < 100 cm2 and onset < 6 months with limited co-morbidities
                • Complex VLU
                  • Area > 100 cm2 and/or wound onset > 6 months (no other co-morbidities)
                  • < 30% decrease in wound area after 4 weeks of adequate treatment
                  • Lymphovenous disease
                  • Associated lipedema
                  • Leg/ulcer infection
                  • Stable cardiac heart failure
                  • History of non-adherence
                • Mixed arterial venous ulcer:
                  • ABI > 1.3: Non-compressible arteries
                  • ABI 0.5-0.8: Mixed arterial ulcer with mild/moderate ischemia
                  • ABI <0.5: Mixed arterial ulcer with severe ischemia

                Ulcer healability 

                This step involves assessing whether the ulcer can be healed with conservative management only (healable) or not (non-healable), or if co-existing medical conditions, drugs or circumstances will likely impede wound healing (maintenance). Ulcer healability classification helps in determining an adequate treatment plan.[47] A summary is provided below; for more details see topic "How to Determine Healability of a Chronic Wound". After determining ulcer healability, see "Venous ulcers - Treatment and Prevention"

                Table 2: Determining ulcer healability 

                * ) As determined by comprehensive patient assessment. Maintenance wounds have healing potential but patient or health system barriers compromise healing (**For persons without diabetes, inadequate blood supply is objectively confirmed by ankle-brachial index (ABI) < 0.5, monophasic doppler waveform, skin perfusion pressure < 30mmHg, transcutaneous oxygen < 30mmHg, absolute systolic ankle pressure < 50 mmHg OR toe pressure < 30mmHg. For persons with diabetes, perform any other testing listed above besides ABI as ABI can be falsely elevated 

                Can underlying cause be treated? How is blood supply to the wound? Co-existing medical conditions/drugs... Then wound prognosis is...
                Yes Adequate Are not an obstacle for healing Healable
                No (*) Adequate May or may not prevent healing Maintenance
                No Usually inadequate (**) May inhibit healing Non-healable

                Modified from Sibbald RG et al. 2011[47].

                • If patient has any of the conditions below, consider a non-healing program. VLU will likely not heal with conservative treatment only:
                  • Co-morbidities that impede healing: 
                    • Ulcer is malignant tumor, 
                    • Major organ failure
                    • Blood supply to the VLU is inadequate as determined by non-invasive vascular arterial tests (ABI, Doppler, TCOM, other exams)
                • If patient has any of the conditions that impede wound healing below, consider a maintenance-healing program until element impeding healing is mitigated:
                  • Co-morbidities:
                    • Uncontrolled diabetes
                    • Immunosuppression
                    • Obesity: BMI > 40
                    • Inadequate nutrition (abnormal serum protein, unintended weight loss)
                    • Cognitive, emotional, psychological dysfunction
                    • Calf muscle pump disfunction (arthritic conditions, paralysis, etc)
                  • Drugs and interventions :
                    • Steroids
                    • Chemotherapy/ radiation
                    • Immunosuppressants
                  • Lifestyle:
                    • Regular smoking
                    • Impaired mobility
                    • Financial or resource constraints

                    Experimental Diagnostics

                    • Ulcer exudate biomarkers measurement with Multiplex ELISA: a single center study found the biomarkers granulocyte macrophage-colony stimulating factor (GM-CSF) and matrix metalloprotease-13 (MMP-13) to be accurate predictive biomarkers of VLU healing. Results suggested that VLUs with GM-CSF values greater than 29.5 pg/mL or with MMP-13 values greater than 962.2 pg/mL in their exudate will not decrease in size (that is, the the VLU is nonhealing), and thus treatment plan should be reassessed.[48] While results are promising, further validation and development of a point-of-care test are needed before use in clinical practice.

                        Documentation

                        • Documentation of VLU is important to assess healing progress, as they determine whether a treatment plan should be continued or not. VLU progress should be recorded weekly or sooner if significant change.
                        • All wound care services provided need to be documented in a way that supports the Medical Necessity requirements, and facilitate evaluation and subsequent care of VLUs. Many VLUs are refractory to healing or have complicated healing cycles either because of the nature of the wound itself or because of complicating metabolic and/or physiological factors.  
                        • Documentation should include number and position of ulcers on the leg. Wound measurements should be made for each VLU, including area, perimeter, and depth, description of wound edge, peri-wound area, wound base quality, amount and type of drainage, and infection, history of debridement. [2]
                          • Wound measurement methods include manually measuring length and width (the longest length with the greatest width at right angles), manual tracing, digital photography, and software programs that calculate wound dimensions from a photograph of the lesion. Wound tracings that calculate the area via digital software are slightly better than linear measurement [5].

                        Documenting signs of VLU improvement to support medical necessity (Medicare):

                        • Reimbursement for wound care services on a continuing basis for a particular wound in a patient requires documentation in the patient's record that the wound is improving in response to the wound care being provided. 
                        • It is not medically reasonable or necessary to continue a given type of wound care if evidence of wound improvement cannot be shown. 
                        • Medicare expects that with appropriate care, wound volume or surface dimension should decrease by at least 10 percent per month or wounds will demonstrate margin advancement of no less than 1 mm/week. 
                        • Medicare expects the wound-care treatment plan to be modified in the event that appropriate healing is not achieved.
                        • Such evidence must be documented with each date of service provided.
                        • Evidence of improvement includes measurable changes (decreases) of some of the following: 
                          • Drainage 
                          • Inflammation
                          • Swelling
                          • Pain
                          • Wound dimensions (diameter, depth) 
                          • Necrotic tissue/slough 

                        Documentation tools: 

                        • Tools that facilitate standardized assessment should be used:
                          • Wound Reference Wound Prep&Dress Tool creates notes to help support medical necessity that can be copied and pasted to electronic medical records
                          • Validated wound assessment tools such as Bates-Jensen Tool.[37] 
                          • Relevant chronic venous disease classification systems such as CEAP (Clinical-Etiology-Anatomy-Pathophysiology) criteria can guide the assessment of CVD Collins [5]. Developed by international consensus, CEAP classifies lower extremity venous disease based upon clinical signs, etiology, anatomic location, and pathophysiologic abnormality. 

                        • Patient reported outcome (PRO) Tools: as part of a patient-centered approach, it is recommended that clinicians adopt PRO tools to assess patient’s Quality of Life (QOL), pain, and depression [7] PROM provide a comprehensive picture of patient’s health [49], which can be used to optimize plan of care.
                          • QOL tools validated for VU patients: the Nottingham Health Profile (NHP) and Venous Leg Ulcer Quality of Life (VLU‐QoL) questionnaire  seem to be the most suitable PROM for use by clinicians.[49] Others include VEINES - QoL/Sym tool, the Medical Outcomes Survey 12 item Short-Form (SF-12) the Short-Form Health Survey, 36 items (SF-36).[7] 
                            •  Medicare Quality Payment Program, Improvement Activity "Promote Use of Patient-Reported Outcome Tools" suggests use of Wound-Quality of Life (QoL) and patient-reported Wound Outcome.[50]
                          • Pain measurement tools validated for VLU patients:  include the Medical Outcomes Survey 12-item Short- Form (SF-12), the Visual     Analogue Scale, and the McGill Pain Questionnaire, a subscale of the Nottingham Health Profile. [7]
                            •  Medicare Quality Payment Program, Quality Measure: "Pain Assessment and Follow-Up"
                          • Depression measurement / assessment tools validated for VLU patients: include the Hospital Anxiety and Depression Scale (HADS), the Euroqol 5 dimensions (EQ-5D), and the Nottingham Health Profile. [7]

                        CODING

                        ICD-10

                        • Identify and document first any documented underlying condition (ICD-10-CM documentation)  
                          • Chronic venous hypertension with ulcer  (I87.31-, I87.33-)Post-phlebitic syndrome with ulcer (I87.01-, I87.03-)
                          • Post-thrombotic syndrome with ulcer (I87.01-, I87.03-)
                          • Varicose ulcer (I83.0-, I.83.2-)
                        • Specify laterality
                          • Right, left or unspecified
                        • Specify ulcer severity: Select code for non-pressure chronic ulcer of the calf [51]
                          • Limited to breakdown of skin
                          • With fat layer exposed
                          • With necrosis of muscle
                          • With necrosis of bone
                          • Unspecified severity

                        APPENDIX      

                        ICD-10 Coding

                        • Red arrows indicate non-billable code, Green arrows are billable codes

                        Coding Chronic venous hypertension (Back to text)

                        I83 Varicose veins of lower extremities

                          I83.0 Varicose veins of lower extremities with ulcer

                               I83.00 Varicose veins of unspecified lower extremity with ulcer

                                    I83.001 …… of thigh

                                    I83.002 …… of calf

                                    I83.003 …… of ankle

                                    I83.004 …… of heel and midfoot

                                    I83.005 …… other part of foot

                                    I83.008 …… other part of lower leg

                                    I83.009 …… of unspecified site

                               I83.01 Varicose veins of right lower extremity with ulcer

                                   I83.011 …… of thigh

                                   I83.012 …… of calf

                                   I83.013 …… of ankle

                                   I83.014 …… of heel and midfoot

                                   I83.015 …… other part of foot

                                   I83.018 …… other part of lower leg

                                   I83.019 …… of unspecified site

                               I83.02 Varicose veins of left lower extremity with ulcer

                                   I83.021 …… of thigh

                                   I83.022 …… of calf

                                   I83.023 …… of ankle

                                   I83.024 …… of heel and midfoot

                                   I83.025 …… other part of foot

                                   I83.028 …… other part of lower leg

                                   I83.029 …… of unspecified site

                           I83.2 Varicose veins of lower extremities with both ulcer and inflammation

                               I83.20 Varicose veins of unspecified lower extremity with both ulcer and inflammation

                                   I83.201 Varicose veins of unspecified lower extremity with both ulcer of thigh and inflammation

                                   I83.202 Varicose veins of unspecified lower extremity with both ulcer of calf and inflammation

                                   I83.203 Varicose veins of unspecified lower extremity with both ulcer of ankle and inflammation

                                   I83.204 Varicose veins of unspecified lower extremity with both ulcer of heel and midfoot and inflammation

                                   I83.205 Varicose veins of unspecified lower extremity with both ulcer other part of foot and inflammation

                                   I83.208 Varicose veins of unspecified lower extremity with both ulcer of other part of lower extremity and inflammation

                                   I83.209 Varicose veins of unspecified lower extremity with both ulcer of unspecified site and inflammation

                               I83.21 Varicose veins of right lower extremity with both ulcer and inflammation

                                   I83.211 Varicose veins of right lower extremity with both ulcer of thigh and inflammation

                                   I83.212 Varicose veins of right lower extremity with both ulcer of calf and inflammation

                                   I83.213 Varicose veins of right lower extremity with both ulcer of ankle and inflammation

                                   I83.214 Varicose veins of right lower extremity with both ulcer of heel and midfoot and inflammation

                                   I83.215 Varicose veins of right lower extremity with both ulcer other part of foot and inflammation

                                   I83.218 Varicose veins of right lower extremity with both ulcer of other part of lower extremity and inflammation

                                   I83.219 Varicose veins of right lower extremity with both ulcer of unspecified site and inflammation

                               I83.22 Varicose veins of left lower extremity with both ulcer and inflammation

                                   I83.221 Varicose veins of left lower extremity with both ulcer of thigh and inflammation

                                   I83.222 Varicose veins of left lower extremity with both ulcer of calf and inflammation

                                   I83.223 Varicose veins of left lower extremity with both ulcer of ankle and inflammation

                                   I83.224 Varicose veins of left lower extremity with both ulcer of heel and midfoot and inflammation

                                   I83.225 Varicose veins of left lower extremity with both ulcer other part of foot and inflammation

                                   I83.228 Varicose veins of left lower extremity with both ulcer of other part of lower extremity and inflammation

                                   I83.229 Varicose veins of left lower extremity with both ulcer of unspecified site and inflammation

                        ICD-10 – post phlebitic (Back to text)

                        • Red arrows indicate non-billable code, Green arrows are billable codes

                               I87.01 Postthrombotic syndrome with ulcer

                                   I87.011 …… of right lower extremity

                                   I87.012 …… of left lower extremity

                                   I87.013 …… of bilateral lower extremity

                                   I87.019 …… of unspecified lower extremity

                               I87.03 Postthrombotic syndrome with ulcer and inflammation

                                   I87.031 …… of right lower extremity

                                   I87.032 …… of left lower extremity

                                   I87.033 …… of bilateral lower extremity

                                   I87.039 …… of unspecified lower extremity

                        ICD-10 – varicose ulcer (Back to text)

                        • Red arrows indicate non-billable code, Green arrows are billable codes

                        I83 Varicose veins of lower extremities

                           I83.0 Varicose veins of lower extremities with ulcer

                               I83.00 Varicose veins of unspecified lower extremity with ulcer

                                   I83.001 …… of thigh

                                   I83.002 …… of calf

                                   I83.003 …… of ankle

                                   I83.004 …… of heel and midfoot

                                   I83.005 …… other part of foot

                                   I83.008 …… other part of lower leg

                                   I83.009 …… of unspecified site

                               I83.01 Varicose veins of right lower extremity with ulcer

                                   I83.011 …… of thigh

                                   I83.012 …… of calf

                                   I83.013 …… of ankle

                                   I83.014 …… of heel and midfoot

                                   I83.015 …… other part of foot

                                   I83.018 …… other part of lower leg

                                   I83.019 …… of unspecified site

                           I83.02 Varicose veins of left lower extremity with ulcer

                                   I83.021 …… of thigh

                                   I83.022 …… of calf

                                   I83.023 …… of ankle

                                   I83.024 …… of heel and midfoot

                                   I83.025 …… other part of foot

                                   I83.028 …… other part of lower leg

                                   I83.029 …… of unspecified site

                           I83.2 Varicose veins of lower extremities with both ulcer and inflammation

                               I83.20 Varicose veins of unspecified lower extremity with both ulcer and inflammation

                                   I83.201 Varicose veins of unspecified lower extremity with both ulcer of thigh and inflammation

                                   I83.202 Varicose veins of unspecified lower extremity with both ulcer of calf and inflammation

                                   I83.203 Varicose veins of unspecified lower extremity with both ulcer of ankle and inflammation

                                   I83.204 Varicose veins of unspecified lower extremity with both ulcer of heel and midfoot and inflammation

                                   I83.205 Varicose veins of unspecified lower extremity with both ulcer other part of foot and inflammation

                                   I83.208 Varicose veins of unspecified lower extremity with both ulcer of other part of lower extremity and inflammation

                                   I83.209 Varicose veins of unspecified lower extremity with both ulcer of unspecified site and inflammation

                               I83.21 Varicose veins of right lower extremity with both ulcer and inflammation

                                   I83.211 Varicose veins of right lower extremity with both ulcer of thigh and inflammation

                                   I83.212 Varicose veins of right lower extremity with both ulcer of calf and inflammation

                                   I83.213 Varicose veins of right lower extremity with both ulcer of ankle and inflammation

                                   I83.214 Varicose veins of right lower extremity with both ulcer of heel and midfoot and inflammation

                                   I83.215 Varicose veins of right lower extremity with both ulcer other part of foot and inflammation

                                   I83.218 Varicose veins of right lower extremity with both ulcer of other part of lower extremity and inflammation

                                   I83.219 Varicose veins of right lower extremity with both ulcer of unspecified site and inflammation

                               I83.22 Varicose veins of left lower extremity with both ulcer and inflammation

                                   I83.221 Varicose veins of left lower extremity with both ulcer of thigh and inflammation

                                   I83.222 Varicose veins of left lower extremity with both ulcer of calf and inflammation

                                   I83.223 Varicose veins of left lower extremity with both ulcer of ankle and inflammation

                                   I83.224 Varicose veins of left lower extremity with both ulcer of heel and midfoot and inflammation

                                   I83.225 Varicose veins of left lower extremity with both ulcer other part of foot and inflammation

                                   I83.228 Varicose veins of left lower extremity with both ulcer of other part of lower extremity and inflammation

                                   I83.229 Varicose veins of left lower extremity with both ulcer of unspecified site and inflammation

                        ICD-10 – nonpressure ulcer (Back to text)

                        • Red arrows indicate non-billable code, Green arrows are billable codes

                           L97.2 Non-pressure chronic ulcer of calf

                                L97.20 Non-pressure chronic ulcer of unspecified calf

                                   L97.201 …… limited to breakdown of skin

                                   L97.202 …… with fat layer exposed

                                   L97.203 …… with necrosis of muscle

                                   L97.204 …… with necrosis of bone

                                   L97.209 …… with unspecified severity

                               L97.21 Non-pressure chronic ulcer of right calf

                                   L97.211 …… limited to breakdown of skin

                                   L97.212 …… with fat layer exposed

                                   L97.213 …… with necrosis of muscle

                                   L97.214 …… with necrosis of bone

                                   L97.219 …… with unspecified severity

                               L97.22 Non-pressure chronic ulcer of left calf

                                   L97.221 …… limited to breakdown of skin

                                   L97.222 …… with fat layer exposed

                                   L97.223 …… with necrosis of muscle

                                   L97.224 …… with necrosis of bone

                                   L97.229 …… with unspecified severity

                        REVISION UPDATES

                        Date Description
                        6/19/19 Updated section 'Assessment', updated references, added new photos, added information on Medicare coverage for noninvasive arterial testing
                        10/24/19Added section 'Experimental Diagnostics', updated references

                        Official reprint from WoundReference® woundreference.com ©2018 Wound Reference, Inc. All Rights Reserved
                        Use of WoundReference is subject to the Subscription and License Agreement. ​
                        NOTE: This is a controlled document. This document is not a substitute for proper training, experience, and exercising of professional judgment. While every effort has been made to ensure the accuracy of the contents, neither the authors nor the Wound Reference, Inc. give any guarantee as to the accuracy of the information contained in them nor accept any liability, with respect to loss, damage, injury or expense arising from any such errors or omissions in the contents of the work.

                        REFERENCES

                        1. Franks, Peter J; Barker, Judith; Collier, Mark; Gethin, Georgina; Haesler, Emily; Jawien, Arkadiusz; Laeuchli, Severin; Mosti, Giovanni; Probst, Sebastian; Weller, Carolina et al. Management of patients with venous leg ulcers: challenges and current best practice. Journal of Wound Care. 2016;volume 25 Suppl 6():S1-S67.
                        2. O'Donnell, Thomas F; Passman, Marc A; Marston, William A; Ennis, William J; Dalsing, Michael; Kistner, Robert L; Lurie, Fedor; Henke, Peter K; Gloviczki, Monika L; Eklöf, Bo G; Stoughton, Ju... et al. Management of venous leg ulcers: clinical practice guidelines of the Society for Vascular Surgery ® and the American Venous Forum. Journal of Vascular Surgery. 2014;volume 60(2 Suppl):3S-59S.
                        3. Callam, M J; Harper, D R; Dale, J J; Ruckley, C V et al. Arterial disease in chronic leg ulceration: an underestimated hazard? Lothian and Forth Valley leg ulcer study. British medical journal (Clinical research ed.... 2017;volume 294(6577):929-931.
                        4. Nelzén, O; Bergqvist, D; Lindhagen, A et al. Venous and non-venous leg ulcers: clinical history and appearance in a population study. The British Journal of Surgery. 1994;volume 81(2):182-187.
                        5. Alavi, Afsaneh; Sibbald, R Gary; Phillips, Tania J; Miller, O Fred; Margolis, David J; Marston, William; Woo, Kevin; Romanelli, Marco; Kirsner, Robert S et al. What's new: Management of venous leg ulcers: Approach to venous leg ulcers. Journal of the American Academy of Dermatolog.... 2016;volume 74(4):627-40; quiz 641.
                        6. Harding, Keith; Dowsett, Caroline; Fias, Lore; et, al et al. Simplifying venous leg ulcer management. Consensus recommendations. . 2017;.
                        7. Couch KS, Corbett L, Gould L, Girolami S, Bolton L et al. The International Consolidated Venous Ulcer Guideline Update 2015: Process Improvement, Evidence Analysis, and Future Goals. Ostomy/wound management. 2017;volume 63(5):42-46.
                        8. Norman G, Westby MJ, Rithalia AD, Stubbs N, Soares MO, Dumville JC et al. Dressings and topical agents for treating venous leg ulcers. The Cochrane database of systematic reviews. 2018;volume 6():CD012583.
                        9. Westby, Maggie J; Norman, Gill; Dumville, Jo C; Stubbs, Nikki; Cullum, Nicky et al. Protease-modulating matrix treatments for healing venous leg ulcers. Cochrane Database of Systematic Reviews. 2016;volume 12():CD011918.
                        10. Valencia, I C; Falabella, A; Kirsner, R S; Eaglstein, W H et al. Chronic venous insufficiency and venous leg ulceration. Journal of the American Academy of Dermatolog.... 2001;volume 44(3):401-21; quiz 422.
                        11. Dumville, J C; Worthy, G; Soares, M O; Bland, J M; Cullum, N; Dowson, C; Iglesias, C; McCaughan, D; Mitchell, J L; Nelson, E A; Torgerson, D J; VenUS II team et al. VenUS II: a randomised controlled trial of larval therapy in the management of leg ulcers. Health Technology Assessment. 2009;volume 13(55):1-182, iii.
                        12. Iglesias, C P; Nelson, E A; Cullum, N; Torgerson, D J; VenUS I collaborators et al. Economic analysis of VenUS I, a randomized trial of two bandages for treating venous leg ulcers. The British Journal of Surgery. 2004;volume 91(10):1300-1306.
                        13. Rice, J Bradford; Desai, Urvi; Cummings, Alice Kate G; Birnbaum, Howard G; Skornicki, Michelle; Parsons, Nathan et al. Burden of venous leg ulcers in the United States. Journal of medical economics. 2014;volume 17(5):347-356.
                        14. Ashby, Rebecca L; Gabe, Rhian; Ali, Shehzad; Adderley, Una; Bland, J Martin; Cullum, Nicky A; Dumville, Jo C; Iglesias, Cynthia P; Kang'ombe, Arthur R; Soares, Marta O; Stubbs, Nikki C; Torg... et al. Clinical and cost-effectiveness of compression hosiery versus compression bandages in treatment of venous leg ulcers (Venous leg Ulcer Study IV, VenUS IV): a randomised controlled trial. The Lancet. 2014;volume 383(9920):871-879.
                        15. Kastner, Monika; Wilczynski, Nancy L; Walker-Dilks, Cindy; McKibbon, Kathleen Ann; Haynes, Brian et al. Age-specific search strategies for Medline. Journal of Medical Internet Research. 2006;volume 8(4):e25.
                        16. AHRQ, et al. Chronic Venous Ulcers: A Comparative Effectiveness Review of Treatment Modalities Comparative Effectiveness Review. 2017;.
                        17. White-Chu, E Foy; Conner-Kerr, Teresa A et al. Overview of guidelines for the prevention and treatment of venous leg ulcers: a US perspective. Journal of multidisciplinary healthcare. 2014;volume 7():111-117.
                        18. . Diagnosis and Treatment of Venous Ulcers - American Family Physician . 2017;.
                        19. Margolis DJ, Bilker W, Santanna J, Baumgarten M et al. Venous leg ulcer: Incidence and prevalence in the elderly J Am Acad Dermatol. 2002;volume 46(3):381–6.
                        20. Meulendijks AM, de Vries FMC, van Dooren AA, Schuurmans MJ, Neumann HAM et al. A systematic review on risk factors in developing a first-time Venous Leg Ulcer. Journal of the European Academy of Dermatology and Venereology : JEADV. 2018;.
                        21. Raffetto JD. Pathophysiology of Chronic Venous Disease and Venous Ulcers. The Surgical clinics of North America. 2018;volume 98(2):337-347.
                        22. Marston WA, Ennis WJ, Lantis JC 2nd, Kirsner RS, Galiano RD, Vanscheidt W, Eming SA, Malka M, Cargill DI, Dickerson JE Jr, Slade HB, HP802-247 Study Group. et al. Baseline factors affecting closure of venous leg ulcers. Journal of vascular surgery. Venous and lymphatic disorders. 2017;volume 5(6):829-835.e1.
                        23. Margolis, David J; Allen-Taylor, Lynne; Hoffstad, Ole; Berlin, Jesse A et al. The accuracy of venous leg ulcer prognostic models in a wound care system. Wound Repair and Regeneration. 2004;volume 12(2):163-168.
                        24. Bergan, John J; Schmid-Schönbein, Geert W; Smith, Philip D Coleridge; Nicolaides, Andrew N; Boisseau, Michel R; Eklof, Bo et al. Chronic venous disease. The New England Journal of Medicine. 2006;volume 355(5):488-498.
                        25. Chi, Yung-Wei; Raffetto, Joseph D et al. Venous leg ulceration pathophysiology and evidence based treatment. Vascular Medicine. 2015;volume 20(2):168-181.
                        26. Raffetto, Joseph D et al. Pathophysiology of wound healing and alterations in venous leg ulcers-review. Phlebology. 2016;volume 31(1 Suppl):56-62.
                        27. Couch KS, Corbett L, Gould L, Girolami S, Bolton L et al. The International Consolidated Venous Ulcer Guideline Update (2015): Process Improvement, Evidence Analysis, and Future Goals. Ostomy/wound management. 2017;volume 63(5):42-46.
                        28. Verma, Himanshu; Tripathi, Ramesh K et al. Algorithm-based approach to management of venous leg ulceration. Seminars in vascular surgery. 2015;volume 28(1):54-60.
                        29. Wounds UK. Best Practice Statement Addressing complexities in the management of venous leg ulcers Wounds UK. 2019;.
                        30. Fiddes R, Khattab M, Abu Dakka M, Al-Khaffaf H et al. Patterns and management of vascular injuries in intravenous drug users: a literature review. The surgeon : journal of the Royal Colleges of Surgeons of Edinburgh and Ireland. 2010;volume 8(6):353-61.
                        31. Bates-Jensen B. Bates-Jensen Wound Assessment Tool .;.
                        32. Noridian Healthcare Solutions, LLC et al. Local Coverage Determination (LCD): Noninvasive Peripheral Arterial Studies (L34219) . 2015;.
                        33. Kazu, Suzuki et al. How To Diagnose Peripheral Arterial Disease | Podiatry Today Podiatry Today. 2007;volume 20(4):.
                        34. Mills, Joseph L; Conte, Michael S; Armstrong, David G; Pomposelli, Frank B; Schanzer, Andres; Sidawy, Anton N; Andros, George; Society for Vascular Surgery Lower Extremity Guidelines Committ... et al. The Society for Vascular Surgery Lower Extremity Threatened Limb Classification System: risk stratification based on wound, ischemia, and foot infection (WIfI). Journal of Vascular Surgery. 2014;volume 59(1):220-34.e1.
                        35. Lavery, Lawrence A; Davis, Kathryn E; Berriman, Sandra J; Braun, Liza; Nichols, Adam; Kim, Paul J; Margolis, David; Peters, Edgar J; Attinger, Chris et al. WHS guidelines update: Diabetic foot ulcer treatment guidelines. Wound Repair and Regeneration. 2016;volume 24(1):112-126.
                        36. Sibley RC 3rd, Reis SP, MacFarlane JJ, Reddick MA, Kalva SP, Sutphin PD et al. Noninvasive Physiologic Vascular Studies: A Guide to Diagnosing Peripheral Arterial Disease. Radiographics : a review publication of the Radiological Society of North America, Inc. 2017;volume 37(1):346-357.
                        37. Hinchliffe, R J; Brownrigg, J R W; Apelqvist, J; Boyko, E J; Fitridge, R; Mills, J L; Reekers, J; Shearman, C P; Zierler, R E; Schaper, N C; International Working Group on the Diabetic Foot et al. IWGDF guidance on the diagnosis, prognosis and management of peripheral artery disease in patients with foot ulcers in diabetes. Diabetes/Metabolism Research and Reviews. 2016;volume 32 Suppl 1():37-44.
                        38. Andersen CA. Noninvasive assessment of lower extremity hemodynamics in individuals with diabetes mellitus. Journal of vascular surgery. 2010;volume 52(3 Suppl):76S-80S.
                        39. Tsai FW, Tulsyan N, Jones DN, Abdel-Al N, Castronuovo JJ Jr, Carter SA et al. Skin perfusion pressure of the foot is a good substitute for toe pressure in the assessment of limb ischemia. Journal of vascular surgery. 2000;volume 32(1):32-6.
                        40. Myers, K A; Ziegenbein, R W; Zeng, G H; Matthews, P G et al. Duplex ultrasonography scanning for chronic venous disease: patterns of venous reflux. Journal of Vascular Surgery. 1995;volume 21(4):605-612.
                        41. Sibbald RG, Goodman L, Woo KY, Krasner DL, Smart H, Tariq G, Ayello EA, Burrell RE, Keast DH, Mayer D, Norton L, Salcido RS et al. Special considerations in wound bed preparation 2011: an update©. Advances in skin & wound care. 2011;volume 24(9):415-36; quiz 437-8.
                        42. Stacey MC, Phillips SA, Farrokhyar F, Swaine JM et al. Evaluation of wound fluid biomarkers to determine healing in adults with venous leg ulcers: A prospective study. Wound repair and regeneration : official publication of the Wound Healing Society [and] the Eur.... 2019;volume 27(5):509-518.
                        43. Poku E, Aber A, Phillips P, Essat M, Buckley Woods H, Palfreyman S, Kaltenthaler E, Jones G, Michaels J et al. Systematic review assessing the measurement properties of patient-reported outcomes for venous leg ulcers. BJS open. 2017;volume 1(5):138-147.
                        44. CMS, Quality Payment Program et al. Explore Measures - Program Performance - Quality Payment Program .;.
                        45. ICD10Data.com, et al. 2017 ICD-10-CM Diagnosis Codes L97.* : Non-pressure chronic ulcer of lower limb, not elsewhere classified . 2017;.
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