How Long-Term Primary Podiatric Care Can Reduce Diabetic Pedal Complications

At the recent annual meeting of the American Podiatric Medical Association (APMA), Gibson and colleagues presented an elegant study confirming what is well known to all podiatric physicians. In patients with diabetes, the study authors noted that “care by podiatrists appears to prevent or delay lower extremity amputation and hospitalization.”1

   Podiatric care may include the use of advanced limb salvage interventions in the presence of limb threatening infections or ischemia. However, no matter how exciting these advances are, primary podiatric care on a long-term basis remains the mainstay to prevent or minimize the complications that require advanced interventions. Effective long-term primary podiatric care is far more desirable for the patient than the risk and disability associated with aggressive limb salvage.

   Foot surgeries, wound care and vascular interventions are necessary elements of limb salvage. Equally important is the fact that education, prescription shoes, orthotics and callus care at regular intervals are required to prevent further significant ulcerations, infection, hospitalization and possible amputation. Such care is essential after surgery for ulcerative lesions and must be provided by a podiatric physician who is willing to take on longitudinal care for high-risk patients with diabetes.

What The Literature Reveals

High-risk patients with diabetes continue to present on a daily basis at our clinics at the Edward Hines, Jr. Veterans Affairs Hospital and the Loyola University Medical Center. In addition to patients at a high risk of ulcers, others with low-grade chronic ulceration can remain free of infection and avoid amputation if they are under regular podiatric care.

   My group demonstrated this in a 2001 review of 233 patients admitted to our hospitals with foot ulceration.2 Ulcerated patients in this series who received care in a podiatry clinic were far less likely to undergo surgery or amputation in comparison to those who had not received podiatric care prior to admission for infected foot ulcerations.

   There are approximately 24 million people in the United States with diabetes and 1.6 million new cases are diagnosed each year.3 Researchers have estimated that 15 percent of these patients will have a diabetic foot ulcer during their lifetime, automatically putting them at high risk for further ulceration or amputation.4

   Diabetes is the most frequent cause of renal failure with over 178,000 people on chronic dialysis.3 A recent study by Ndip and colleagues indicated that 95 percent of a group of 466 patients on dialysis in the United States and United Kingdom were at high risk for lower limb complications.5 In another study involving 150 patients on dialysis and 150 patients with previous foot ulceration or amputation, Lavery and co-workers found that only 30 percent of the study patients received preventative podiatric care.6

   As we advance in our abilities to utilize sophisticated diagnostic and surgical interventions for treating diabetic foot complications, we must not lose sight of the fact that longitudinal primary podiatric care remains the cornerstone of prevention. Primary podiatric evaluation and management services should be a part of all diabetes care programs to prevent or minimize first episodes of diabetic foot ulceration and limb-threatening infection.

   Such services are even more essential for patients with complications like renal failure or previous limb threatening ulceration and infection. Advanced healing and reconstructive techniques have little value to the patient if a subsequent focal pressure callus leads to ulceration and further limb-threatening infection. Diabetic neuropathy and vascular disease associated with even minor foot deformity are chronic conditions requiring longitudinal care.

Case Study: Underscoring The Impact Of Preventive Care Over Two Decades For A Woman With Type 1 Diabetes

The patient is a 62-year-old woman with type 1 diabetes, which is well controlled. She has received regular care at a podiatry clinic since 1989. She has received education about the importance of good control and the potential for foot complications. She is very attentive to her diabetes care.

   In spite of efforts to control her diabetes, she has a 45 pack-year history of tobacco use and continues to smoke on a limited basis to this day. She runs a part-time catering business and is active in community affairs so she spends a fair amount of time on her feet.

   As I previously noted, the patient’s podiatric care dates back to 1989 when she ulcerated her right fifth toe. She presented with an absence of pedal pulses and received a vascular consult. The vascular surgeon identified significant vascular disease and performed a femoral popliteal bypass. Her toe required amputation but healed uneventfully after the bypass.

   The patient started developing an ulcerating, painless callus under her first metatarsal head shortly after the toe healed. Conservative measures failed to resolve the callus so the surgeon performed a tibial sesamoidectomy. She healed and the callus resolved for a period of time. The callus eventually recurred within a year and ulcerated again. Treatment for the ulceration consisted of debridement, antibiotic ointment, gauze dressings and prescription footwear. It resolved within a month.

   Since that time, the patient has been wearing prescription shoes and orthotics, and has podiatric evaluation and management on a regular basis. Her visits include callus care every two to four weeks for the past 20 years. The frequency of her visits has depended on her activity level and the observed thickness of the keratosis along with evidence of intradermal hemorrhage or pre-ulcerative breakdown.

   If she goes more than three weeks without a podiatric visit, the first metatarsal callus ulcerates in spite of her constant use of prescription footwear. Without frequent callus care, prescription footwear and education about her foot risks, there is little or no question that she would develop serious ulceration, infection and possibly require amputation arising from this painless, chronic pressure keratosis.

   In addition to the aforementioned chronic plantar callus on the first metatarsal, the patient also has a stage 3 Charcot joint on her left foot and a third hammertoe with a chronic distal keratosis and history of ulceration. She has worn inlay depth shoes with custom multidensity accommodative insoles for nearly 20 years.

How The Podiatrist Addressed A Navicular Fracture Suffered By The Patient

In 2006, the patient sustained a minor left foot injury, which resulted in a relatively painless swelling across the top of the foot. She called for an office visit within 48 hours of the injury and presented the next day. An X-ray demonstrated a navicular fracture, which split the bone in two fragments. One of the fragments displaced dorsally and tented her skin, causing the swelling. Eventually, this tenting produced a 4 to 5 cm patch of ischemic necrosis.

   She clearly needed excision of the fragment and debridement of the necrotic tissue but she had non-palpable pulses. The patient had a collapsed arch, which was consistent with a diagnosis of Charcot joint. There were no plantar prominences. The podiatrist determined that the risks of an extensive reconstruction outweighed the potential benefit.

   Before undergoing any foot surgery, the patient received a vascular consult. She had extensive iliac occlusion on both sides and underwent an aortobifemoral bypass. Her peripheral circulation improved. The podiatric surgeon debrided the ischemic patch and excised the navicular fracture fragment.

   We subsequently utilized vacuum assisted closure and immobilized her foot in bulky soft dressings for approximately six weeks. She did not undergo any extensive reconstruction of her Charcot joint other than excision of the displaced fracture fragment.

   She has remained stable and plantigrade. The patient has demonstrated no plantar prominences and no ulceration of the left foot to date, except for a distal third toe ulcer, which resolved with local care. She received a prescription custom orthotic along with inlay depth shoes.

   The patient continues her regular podiatric visits. There have been no significant ulcerations or infections since 2006. At each visit, she receives encouragement for her diligent efforts to control her diabetes, reminders about the adverse effects of smoking and advice to inspect her feet frequently. The physician evaluates vascular status, sensation, skin condition and deformities at each visit. Her pressure calluses undergo evaluation for ulceration and the podiatric physician pares down her calluses. The podiatrist inspects her shoes and orthotics, and provides prescriptions for footwear replacement as needed.

   Over the years, the patient has become quite knowledgeable about her foot condition and the need to observe and seek attention for any foot abnormalities she detects between visits. Her clinical course to this date has been marked by several limb-threatening complications of diabetes that could have led to major amputation. However, self-examination and early intervention have minimized her morbidity.

Recognizing Conditions That Increase Amputation Risk

This patient has exhibited loss of sensation, deformity and a past history of ulceration, which places her in a high risk category for amputation risk, according to the International Working Group on the Diabetic Foot.7 The patient also has peripheral vascular disease.

   According to the American Diabetes Association, the following conditions are associated with an increased risk of amputation:4
• peripheral neuropathy;
• altered biomechanics;
• pressure callus;
• limited joint mobility, bony deformity, severe nail pathology;
• peripheral vascular disease; and/or
• a history of ulcer or amputation.

   Again, the patient exhibited virtually all of these findings. She potentially could have undergone bilateral amputations but her longitudinal podiatric medical, orthotic and surgical care for the past 21 years has enabled her to reduce her risk of lower extremity amputation.

   Dr. Sage is a Professor and the Chief of the Section of Podiatry at the Department of Orthopaedic Surgery and Rehabilitation at the Loyola University Stritch School of Medicine in Maywood, Ill.

   Dr. Steinberg is an Associate Professor in the Department of Plastic Surgery at the Georgetown University School of Medicine in Washington, D.C. He is a Fellow of the American College of Foot and Ankle Surgeons.

   For further reading, see “How To Address Vascular Complications With Lower Extremity Wounds” in the July 2008 issue of Podiatry Today. To access the archives, visit www.podiatrytoday.com.

References:

1. Gibson TB, Driver VR, Wrobel J, Christina JR, Bagalman E, DeFrancis R, Garafoulis MG, Carls GS, Wang SS. Podiatrist care and outcomes for patients with diabetes and foot ulcer. Presented at 98th Annual Scientific Meeting of the American Podiatric Medical Association, July 15-18, 2010, Seattle, Wash. 2. Sage RA, Webster JK, Fisher SG. Outpatient care and morbidity reduction in diabetic foot ulcers associated with chronic pressure callus. JAPMA 2001; 91(6):275-291. 3. Centers for Disease Control and Prevention. National diabetes fact sheet: general information and national estimates on diabetes in the United States, 2007. U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, Atlanta, 2008. 4. Mayfield JA, Reiber GE, Sanders LJ, Janisse D, Pogach LM. Preventive foot care in people with diabetes, technical review and position statement. Diabetes Care 1998; 21(12):2161-2179. 5. Ndip A, Lavery LA, LaFontaine J, Rutter MK, Vardhan A, Vileikyte L, Boulton AJM. High levels of foot ulceration and amputation risk in a multiracial cohort of diabetic patients on dialysis therapy. Diabetes Care 2010; 33(4):878-880. 6. Lavery LA, Hunt NA, LaFontaine J, Baxter CL, Ndip A, Boulton AJM. Diabetic foot prevention: a neglected opportunity in high-risk patients. Diabetes Care 2010; 33(7):1460-1462. 7. International Working Group on the Diabetic Foot. Available at https://www.iwgdf.org/ .