Diabetic Foot.pptx
- 1. DIABETIC FOOT CHAPTER 85 CAMPBELLS
- 2. HISTORY AND PHYSICAL EXAMINATION The physician should inquire about : any episodes of ulceration prior amputations known neuropathic arthropathy impaired vision renal history presence of paresthesias or numbness any symptoms of claudication patients may deny any history of trauma or pain before the development of a foot ulcer
- 3. A difference in skin temperature of the foot may indicate the presence of a vascular disease
- 4. Diminished or absent pulses require further testing with a Doppler examination
- 5. The ankle-brachial index (ABI) is a useful noninvasive screening tool that is predictive of wound healing. A normal ABI is 0.9 to 1.2 while values over 1.3 suggest noncompressible vessels due to calcification. An ABI of less than 0.5 suggests that an ulcer is unlikely to heal without vascular intervention
- 6. A difference in ABI of more than 0.15 between extremities is a significant finding and should be further investigated.
- 7. Absolute toe pressures should be higher than 70 mmHg, and a normal toe/brachial index of more than 0.7 is normal. Toe pressures of more than 40 mmHg are associated with wound healing.
- 8. A neurologic examination evaluates for the presence or absence of peripheral neuropathy.
- 9. Semmes-Weinstein monofilament The inability to feel the 10 g of pressure from this monofilament is one of the most predictive risk factors for development of foot morbidity. Typical screening involves 10 g monofilament testing of 10 sites on the foot
- 11. equivalent results can be obtained more quickly using a 4.5 g monofilament beneath both first metatarsal heads. Decreased perception of the vibration of a 128 Hz tuning fork at the tip of the great toe also is used in clinical practice.
- 12. ULCER CLASSIFICATION Ince et al. found that of 410 diabetic foot ulcers, 96% of those less than 1-2 cm in dimension eventually healed without any form of amputation, while only 72% of ulcers larger than 2-3 cm did so
- 20. LABORATORY EVALUATION Patients with hemoglobin A1c levels higher than 7% or preoperative glucose levels of more than 200 mg/dL before ankle or hindfoot arthrodesis have a higher rate of complications, including nonunion, infection, and wound healing problems.
- 21. If infection is suspected clinically: complete blood count(CBC) erythrocyte sedimentation rate (ESR) C-reactive protein (CRP)
- 23. TREATMENT The primary goals of treatment of diabetic foot ulcers are : healing of the ulcer prevention of secondary infection recurrence avoidance of amputation
- 24. The most standard treatments are debridement and off-loading of the affected area
- 25. Because of the complexities of treating diabetic feet, including : impaired blood supply osteoporotic bone neuropathy a multidisciplinary approach is most beneficial
- 26. Expertise often is needed from subspecialists in orthopaedics, vascular Surgery , infectious disease , endocrinology, and wound nursing.
- 27. Vascular consultation should be considered when rest pain , claudication , or ischemic ulcers are present.
- 28. Endocrinology may assist if blood glucose levels cannot be controlled by the primary care practitioner or if the patient shows unusual response to standard glycemic control measures.
- 29. Infectious disease consultation may be helpful when a patient fails to respond to empiric antibiotic therapy.
- 30. Systemic factors, including glucose control , smoking, and diet, should be controlled to optimize the wound-healing environment
- 31. Using the Wagner classification of foot ulcers: grade 0 ulcers should be treated with serial examinations, patient education, accommodative footwear. Grade I ulcers can be treated with debridement in the clinic and off-loading total contact cast, walking brace, or other custom footwear.
- 32. Grade II ulcers require surgical debridement culture-specific antibiotics off-loading with total anesthetic.
- 33. Grade III ulcers require surgical debridement or partial amputation with off-loading and culture specific antibiotics.
- 34. Grades IV and V ulcers require local or larger amputation based on the extent of infection.
- 35. In the ischemic classification of Brodsky et al : type B ischemia should be considered for noninvasive vascular testing and reconstruction with bypass or angioplasty.
- 36. Type C involvement may require reconstructive vascular surgery with partial amputation
- 37. while type D requires thorough vascular evaluation and likely major extremity amputation.
- 38. Negative pressure wound therapy(NPWT) devices are another option to assist in ulcer healing. The exact mechanism of action of NPWT is unknown;however, studies have shown that it may increase local blood flow, decrease edema, and increase the concentration of growth factors in the local wound fluid
- 39. Cultures of the ulcer generally are not recommended because the sensitivity in isolating the causative organism is low
- 40. Most ulcers are colonized with bacteria that has not invaded the deep tissue and do not require antibiotics. When wound cultures are obtained , this should be done after thorough debridement of the wound
- 41. Harsh chemicals such as hydrogen peroxide and betadine should not be applied because these can damage the viable tissue in the ulcer and further delay healing.
- 42. Routine nail care may be provided by the physician or nurse if the patient is unable to do so. A straight nail clipper should be used to transversely cut the nail to avoid any skin overgrowth at the medial and lateral borders, which may increase the chance of developing an ingrown nail.
- 43. Hyperbaric oxygen (HBO) has been used as a treatment for diabetic foot ulcers, and randomized trials have shown 54% healing using HBO compared with 25% for standard methods.
- 44. PATIENT EDUCATION Patient education for diabetic patients has been shown to be cost-effective, improve patient quality of life, and reduce the risk of lower extremity amputation by 50% to 85%.
- 45. Patients should be reminded to wear shoes at all times. Feet should be inspected daily, and any signs of erythema, ulceration, or nail problems should be brought to the attention of the care provider.
- 46. Feet should be bathed daily with mild soap and a soft brush for the areas around the nails.
- 47. When drying the feet, attention should be paid to the web spaces because these areas often trap moisture. If the web spaces remain overly moist, lamb’s wool may be placed in between the toes to avoid maceration.
- 48. TOTAL CONTACT CASTING Reducing pressure on plantar ulcers is crucial to aid healing. Forefoot pressures can be reduced with prefabricated shoes more easily than midfoot or hindfoot ulcers.
- 49. Total contact casting is more effective than prefabricated shoes for the midfoot and hindfoot (Fig. 85-11).
- 52. A total contact cast redistributes forces from the plantar surface of the foot to the leg , which reduces the force on the foot even with weight- Bearing activity.
- 53. Total contact casting also is beneficial in that it reduces edema in the extremity, which is why the cast must be changed regularly to prevent loosening that can lead to further ulceration.
- 54. Total contact casting for plantar ulcers showed significantly better healing (89.5%) than removable prefabricated walking boots (65%) or shoes (58%).
- 56. This is similar to the 88% healing rate reported at 41 days with total contact casting alone in a study comparing casting alone to casting with percutaneous Achilles lengthening.
- 57. Patients have been shown to decrease their activity over the course of a day in a total contact cast, which reduces the stress on the foot.
- 58. Total contact casting is not a benign treatment, however; it has been shown to have a 6% to 17% occurrence of new ulcer formation and a 0.25% rate of permanent sequelae
- 59. Contraindications of Total contact cast absolute: active or acute deep infection,gangrene(wagner grade 3-5) deep tissue infection osteomyelitis exposed tendone , joint and bone arterial insufficiency/gangrene
- 60. Relative: severe obesity ulcer depth greater than ulcer width fragile skin fluctuating edema patient unwilling to have cast on limb patient unable to comply with follow up visit Doppler ABI less than ./4
- 61. SURGICAL MANAGEMENT Indications for surgical management are grossly contaminated wounds, unbraceable deformity, gastrocnemius contracture, underlying bone prominence that impedes wound healing, and failure of conservative management.
- 62. Prophylactic surgery may be considered in patients who are at risk for wound breakdown because of joint instability or bony prominence.
- 63. Flexor tenotomy as treatment for isolated toe ulcerations showed over 90% healing rates in a mean of 40 days, with a 12% recurrence rate at 2-year follow up.
- 64. Ulcerations at the medial interphalangeal joint of the hallux can be treated by resection of the medial condyles of the proximal and distal phalanges.
- 65. Plantar metatarsophalangeal joint ulcerations are common, difficult to heal, and associated with a high risk of amputation.
- 66. Achilles tendon lengthening and/or gastrocnemius recession should be considered for patients with forefoot ulcers in whom conservative management has failed and contractures have developed.
- 68. Exostectomy may be required in patients with bony deformity and ulceration. A sufficient period of off-loading with total contact casting should be completed before surgery.
- 69. For patients in whom other surgical management fails , who have non reconstructable vascular disease, or in whom infection is uncontrollable, amputation is the last surgical option.
- 70. The National Diabetes Advisory Board estimates that approximately 5% to 15% of diabetic patients will require a lower-extremity amputation in their lifetime.
- 71. The level of amputation depends on the location of infection and likelihood of healing of the surgical wound.
- 72. One-year mortality after transtibial amputation is 20%, with a 5-year mortality of 65%. Preservation of a portion of the foot gives the patient an end-bearing limb that facilitates ambulation without a prosthesis and improves Functional outcome.
- 73. In the forefoot, ray resection or transmetatarsal amputation may be sufficient in a patient with palpable pulses; however, the same wound in a patient with vascular pathology may require transtibial amputation
- 74. In the midfoot,a talonavicular-calcaneocuboid disarticulation (Chopart) or syme amputation may allow ambulation without prosthesis. A viable heel pad is required for a Syme amputation
- 78. Syme Amputation
- 81. Boyd Amputation
- 82. The single most important factor predicting success of a partial foot amputation is the hemoglobin A1C level at time of surgery, with some authors recommending no elective or trauma surgery for a diabetic patient with an A1C level of more than 8% unless necessary to save life or limb.
- 83. CHARCOT ARTHROPATHY Diabetes is the most common cause of Charcot arthropathy today, but other etiologies include syphilis, heavy metal poisoning, alcoholic or congenital neuropathy, leprosy, rheumatoid arthritis, and idiopathic causes
- 84. The neurovascular, or French, theory was first proposed by Charcot and suggests that neurologic damage precedes and is responsible for the destructive changes. It proposes that damage to the nervous system causes autonomic dysfunction, which increases local blood flow due to arteriovenous shunting and leads to bone resorption
- 85. The neurotraumatic, or German, theory supported by Virchow and Volkman suggests that repetitive microtrauma causes the bony changes due to absent protective mechanisms.
- 86. CLASSIFICATION Type 1 involving the tarsometatarsal and naviculocuneiform joints is most common (60%). Midfoot involvement, specifically the tarsometatarsal joints characterized by hindfoot valgus as a result of forefoot abduction with a contracted gastrocsoleus complex
- 87. Type 2 is the second most common type (25%) and primarily involves the hindfoot, including the subtalar, talonavicular, and calcaneocuboid joints, and may also progress to a rocker-bottom deformity
- 89. Type 3A (10%) involves the ankle and often results in ulcerations over the prominent malleoli. Ankle involvement generally requires operative intervention because of marked instability. Type 3B (5%) presents as a pathologic fracture of the calcaneal tuberosity from avulsion
- 92. TREATMENT Stage 1 disease is treated with a total contact cast, which offloads the involved region and provides stability and alignment through the healing phases.
- 93. stage 2 , patients can be transitioned into a prefabricated boot or a custom- molded ankle-foot-orthosis.
- 94. When consolidation is complete and swelling resolves completely (stage 3) intensive treatment, up to 50% may require surgical intervention
- 95. Vitamin D supplementation should be considered for all patients because research has shown frequent hypovitaminosis D in diabetic patients and clarified its role in the pathogenesis and treatment of Charcot arthropathy.
- 96. The primary goals of surgical intervention are to prevent ulceration, infection, and amputation by decreasing sites of underlying pressure and improving alignment and stability of the foot.
- 97. Exostectomy is most beneficial in Brodsky type 1 deformities in which tarsometatarsal destruction leads to rockerbottom deformity and increased midfoot plantar pressures
- 98. Patients with instability and resultant pain or ulceration may be best treated with arthrodesis
- 99. Type 1 deformities generally require midfoot arthrodesis, while type 2 deformities require triple arthrodesis
- 100. In patients with uncontrollable infection or failed operative treatment, amputation preserving as much length as possible may be the best option
- 101. An estimated 2% to 3% of patients with Charcot arthropathy have amputations