The diabetic foot


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An example of locality guidelines for the management of the diabetic neuropathy and the diabetic foot.

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The diabetic foot

  1. 1. THE DIABETIC FOOT Dr Samer Al-sabbagh Consultant DiabetologistEast & North Hertfordshire NHS Trust
  2. 2. Outline• Epidemiology of Diabetes, foot ulceration and LEA• Foot ulcers and LEA• Risk factors of foot ulceration• Prevention of foot ulceration• The MDT foot team and NICE• Classifications of foot ulcers• Management of diabetic foot ulcers• Charcot’s neuroarthropathy
  3. 3. •Diabetes is one of the biggest healthchallenges facing the UK today•In 2010, 2.3 million people in the UK wereregistered as having diabetes, while thenumber of people estimated as having eithertype 1 or type 2 diabetes was 3.1 million•By 2030 it is estimated that more than 4.6million people will havediabetes (Diabetes UK, 2010)
  4. 4. Major Complications of Diabetes Microvascular Macrovascular A LeadingPeripheral Nervous System Brain and Cerebral Circulation Cause of Death (Cerebrovascular disease)(Neuropathy) Heart and Coronary CirculationKidney (Nephropathy) (Coronary heart disease)Eyes (Retinopathy) Diabetes Lower Limbs (Peripheral vascular disease)Diabetic Foot Diabetic Foot(Ulceration and amputation) Reduced Life (Ulceration and amputation) ExpectancyAmos AF, et al. Diabet Med. 1997;14(Suppl 5):S7-S85. Meltzer S, et al. CMAJ. 1998;20(Suppl 8):S1-S29.
  5. 5. Foot ulceration• Foot ulceration is common and occurs in both type 1 and 2 DM• Approximately 5-10% of patients with diabetes have had past or present foot ulceration, and 1% have undergone amputation• A large community study in the UK showed annual incidence of ulceration of approximately 2%, this rises to 7% in those known diabetic neuropathy
  6. 6. Identifying at risk feet – Deformed toes
  7. 7. • Lower-extremity amputation (LEA) is one of the complications of diabetes that is perhaps most feared by patients with this disease (1) and rightfully so.• These LEAs are generally the end point of a characteristic sequence of events: a foot wound, usually a consequence of peripheral neuropathy, becomes infected and does not respond to treatment (2) – (1) Singh N, Armstrong DG, Lipsky BA Preventing foot ulcers in patients with diabetes. JAMA 2005;293:217–228pmid:15644549 (2) Reiber GE, Pecoraro RE, Koepsell TD Risk factors for amputation in patients with diabetes mellitus: a case-control study. Ann Intern Med 1992;117:97–105pmid:1605439
  8. 8. Patient with Diabetes Risk factors for ulceration?• Peripheral neuropathy• Peripheral vascular disease• Foot deformity• Oedema• Past ulcer history (high incidence up to50%)• Other complication
  9. 9. • Although the factors associated with diabetic people developing a foot ulcer are well defined (1), risk factors for amputation are less clear• Studies have identified independent risk factors that include (in approximate order of odds ratio) -A history of a foot ulcer (6) (1) Singh N, Armstrong DG, Lipsky BA Preventing foot ulcers in patients with diabetes. JAMA 2005;293:217–228pmid:15644549 (6)Krittiyawong S, Ngarmukos C, Benjasuratwong Y,et al Thailand diabetes registry project: prevalence and risk factors associated with lower extremity amputation in Thai diabetics. J Med Assoc Thai 2006;89(Suppl. 1):S43–S48pmid:17715833
  10. 10. – limb ischemia, underlying bone involvement, the presence of gangrene (e.g., a higher Wagner grade), deep wounds– older age, elevated inflammatory markers (7)– Poor glycemic control (8)– A specific ethnicity or geographical region (9,10)– nephropathy (8), and retinopathy (6) (7) Yesil S, Akinci B, Yener S, et al Predictors of amputation in diabetics with foot ulcer: single center experience in a large Turkish cohort. Hormones (Athens) 2009;8:286–295pmid:20045802 (8) Shojaiefard A, Khorgami Z, Larijani B Independent risk factors for amputation in diabetic foot. Int J Diabetes Dev Ctries 2008;28:32– 37pmid:19902045 (9)Chaturvedi N, Stevens LK, Fuller JH, Lee ET, Lu M; WHO Multinational Study of Vascular Disease in Diabetes. Risk factors, ethnic differences and mortality associated with lower-extremity gangrene and amputation in diabetes. Diabetologia 2001;44(Suppl. 2):S65–S71pmid:11587052 (10)Gonsalves WC, Gessey ME, Mainous AG 3rd, Tilley BC A study of lower extremity amputation rates in older diabetic South Carolinians. J S C Med Assoc 2007;103:4–7pmid:17763819
  11. 11. Peripheral neuropathy• All three components of neuropathy; sensory, motor and autonomic can contribute to ulceration• Chronic sensorimotor neuropathy is common, affecting at least one third of older patients in Western Countries• Therefore, assessment of the foot ulcer risk must always include careful foot examination, whatever the history
  12. 12. Distal Symmetric Polyneuropathy is the most common form of neuropathy Prevalence of neuropathy in the Rochester diabetic 100 neuropathy study, 1986 90 80 70 60.4 Patients (%) 60 50 47.3 40 31.7 30 20 10 4.8 0 All Distal Carpal tunnel Autonomic neuropathy polyneuropathy syndrome neuropathy Adapted from Eastman, R.C., Neuropathy in Diabetes in Diabetes in America , pp. 339-348, 2nd Ed., 1995, NIH Publication No. 95-1468
  13. 13. Prevalence of DPNP in Type 2 Diabetes126% of Type 2 patients had DPNP associatedwith decreased quality of life 26% 80% of these patients report moderate to severe painType 2Diabetics1. Davies M, et al. Diabetes Care. 2006;29:1518—22.
  14. 14. NICE guideline for Neuropathic Pain management - DPNP1.11 - For people with painfuldiabetic neuropathy, offer oralduloxetine as first-line treatment. Ifduloxetine is contraindicated, offer 1st Line – Duloxetine *oral amitriptyline.1.13 - For people with painfuldiabetic neuropathy:− if first-line treatment was withduloxetine, switch to amitriptyline orpregabalin, or combine withpregabalin 2nd Line – Switch to Amitriptyline * *− if first-line treatment was with or Pregabalinamitriptyline, switch to or combinewith pregabalin....“1.14 - If satisfactory pain reductionis not achieved with second-linetreatment:• refer the person to a specialist 3rd Line – Refer to specialist Painpain service and/or a condition-specific service” Centre NICE. Neuropathic pain. CG96. London: * If Contraindicated – Use Amitriptyline * * NICE; March 2010 ( ** Not licensed for DPNP
  15. 15. Autonomic neuropathy• Sympathetic autonomic neuropathy affecting the lower limbs results in reduced sweating, dry skin, and development of cracks and fissures.• In the absence of large vessel arterial disease, there may be increased blood flow to the foot, with arteriovenous shunting leading to the warm but at risk foot
  16. 16. Identifying at risk feet –very dry skin
  17. 17. Peripheral Vascular Disease• PVD itself in isolation rarely causes ulceration• Combination of PVD and minor trauma can lead to ulceration• Minor injury and subsequent infection increase the demand for blood supply beyond the circulatory capacity, and ischaemic ulceration and risk of amputation develop• Early identification of PVD is essential
  18. 18. PVD• The presence of a Dorsalis Pedis and Posterior Tibial pulse is the simplest and most reliable indicator of significant ischaemia• Doppler derived ankle pressure can be misleadingly high in longstanding DM• Noninvasive studies together with arteriography often leads to bypass surgery• Distal bypass surgery is often performed with good short term and long term results in limb salvage
  19. 19. Past Foot Ulceration, Foot Surgery & Other Diabetic Complications• More than 50% of patients with new foot ulcers give a past ulcer history• Patients with retinopathy and renal dysfunction are at increased risk for foot ulceration
  20. 20. Callus, Deformity and high foot pressures• Motor neuropathy with imbalance of the flexor and extensor muscles in the foot commonly results in foot deformity with prominent metarsal heads and clawing of the toes• In turn, the combination of the proprioceptive loss due to neuropathy and the prominence of metatarsal heads leads to increases in the loads and pressures under the diabetic foot
  21. 21. Identifying at risk feet –clawed toes
  22. 22. Identifying at risk feet- Plantar Callosity
  23. 23. Prevention of Foot Ulceration and Amputation• The most important message to practitioners is to have the patient remove the shoes and socks and to look at the feet for risk factors ( presence of callus, deformity, muscle wasting, and dry skin)• That diabetic foot ulceration is largely preventable is not disputed; small, mostly single-center studies have shown that relatively simple interventions can reduce amputations by up to 80%
  24. 24. Prevention of foot ulcerationA simple neurologic examination that mightinclude a modified neuropathy disability scoreis recommended; in the large UK communitystudyAbbott CA, Carrington AL, Ashe H, et al:The North-West diabetes foot care study: incidence of, and risk facDiabetic Med 2002; 20:277-384
  25. 25. • this simple clinical exam was the best predictor of foot ulcer risks Absence of the ability to perceive pressure from a 10-g monofilament, inability to perceive a vibrating 128-Hz tuning fork over the hallux, and absent ankle reflexes all have been shown to be predictors of foot ulceration• Bowker JH, Pfeifer MA, ed. Levin & ONeals The Diabetic Foot, 7th ed. St Louis: Mosby; 2006• Boulton AJM, Vileikyte L, Kirsner RS: Neuropathic diabetic foot ulcers. N Engl J Med 2004; 251:48-55• Boulton AJM: The diabetic foot: from art to science. Diabetologia 2004; 47:1343-1353
  26. 26. The Diabetic Foot Care Team• Patients identified as being at high risk for foot ulceration should be managed by a team of specialists with interest and expertise in the diabetic foot. The podiatrist generally takes responsibility for follow-up and care of the skin and nails and, together with the specialist nurse or diabetes educator, provides foot care education
  27. 27. • The orthotist, or shoe fitter, is invaluable for advising about and sometimes designing footwear to protect high-risk feet, and these members of the team should work closely with the diabetologist and the vascular and orthopedic surgeons• Patients with risk factors for ulceration require preventive foot care education and frequent review Boulton AJM: Why bother educating the multidisciplinary team and the patient? The example of prevention of low Patient Educ Counsel 1995; 26:183-188
  28. 28. Diabetic foot problemsInpatient management of diabeticfoot problems
  29. 29. Multidisciplinary foot care teamEach hospital should have a care pathway for patients with diabeticfoot problems who require inpatient care1.The multidisciplinary foot care team should consist ofhealthcareprofessionals with the specialist skills and competenciesnecessary todeliver inpatient care for patients with diabetic foot problems.The multidisciplinary foot care team should normally include adiabetologist, a surgeon with the relevant expertise in managingdiabetic foot problems, a diabetes nurse specialist, a podiatrist anda tissue viabilitynurse, and the team should have access to other specialistservices required to deliver the care outlined in this guideline.
  30. 30. The multidisciplinary foot care team should:assess and treat the patient’s diabetes, which should includeinterventions to minimise the patient’s risk of cardiovascular events,and any interventions for pre-existing chronic kidney disease or anaemia(please refer to ‘Chronic kidney disease’ [NICE clinical guideline 73] and‘Anaemia management in people with chronic kidney disease’ [NICEclinical guideline 114])assess, review and evaluate the patient’s response to initial medical,surgical and diabetes management•assess the foot, and determine the need for specialist wound care,debridement, pressure off-loading and/or other surgicalinterventions•assess the patient’s pain and determine the need for treatmentand access to specialist pain services
  31. 31. •perform a vascular assessment to determine the needfor further interventions•review the treatment of any infection•determine the need for interventions to prevent thedeterioration and•development of Achilles tendon contractures and otherfoot deformities•perform an orthotic assessment and treat to preventrecurrent disease of the foot•have access to physiotherapy•arrange discharge planning, which should include makingarrangements for the patient to be assessed and their caremanaged in primary and/or community care, and followedup by specialist teams.
  32. 32. Initial examination and assessmentRemove the patient’s shoes, socks, bandages and dressingsand examinetheir feet for evidence of:•neuropathy•ischaemia•ulceration•inflammation and/or infection•deformity•Charcot arthropathy.•Document any identified new and/or existing diabetic footproblems.•Obtain urgent advice from an appropriate specialist if any ofthe followingare present:-Fever or any other signs or symptoms of -systemic sepsis.-Clinical concern that there is a deep-seated infection (forexamplepalpable gas).-Limb ischaemia.
  33. 33. Care: within 24 hours of a patient with diabetic footproblems beingadmitted to hospital, or the detection of diabetic footproblems (if thepatient is already in hospital)Refer the patient to the multidisciplinary foot care teamwithin 24 hours ofthe initial examination of the patient’s feet. Transfer theresponsibility ofcare to a consultant member of the multidisciplinary footcare team if adiabetic foot problem is the dominant clinical factor forinpatient care
  34. 34. WAGNER DIABETIC FOOT ULCER CLASSIFICATIONSYSTEMModified from Oyibo S, Jude EB, Tarawneh I,et al: A comparison of two diabetic foot ulcer classification systems: the Wagner and the 2001;24:84-88. Grade Description 0 No ulcer, but high-risk foot (e.g., deformity, callus, insensitivity) 1 Superficial full-thickness ulcer 2 Deeper ulcer, penetrating tendons, no bone involvement 3 Deeper ulcer with bone involvement, osteitis 4 Partial gangrene (e.g., toes, forefoot) 5 Gangrene of whole foot
  35. 35. TABLE 32-15 -- UNIVERSITY OF TEXAS WOUNDCLASSIFICATION SYSTEMModified from Armstrong DG, Lavery LA, Harkless LB.Validation of a diabetic wound classification system. Diabet Med 1998;14:855-859. Stage Grade 0 Grade 1 Grade 2 Grade 3 A Preulcer or Superficial ulcer Deep ulcer to Wound postulcer lesion tendon or penetrating capsule bone or joint No skin break B + Infection + Infection + Infection + Infection C + Ischemia + Ischemia + Ischemia + Ischemia D + Infection and + Infection and + Infection and + Infection and ischemia ischemia ischemia ischemia
  36. 36. Management of diabetic foot ulcersBasically, a diabetic foot ulcer will heal if thefollowing conditions are satisfied • Arterial inflow is adequate. • Infection is treated appropriately. • Pressure is removed from the wound and the immediate surrounding area(1)The most common cause of nonhealing ofneuropathic foot ulcers is the failure to removepressure from the wound and immediatesurrounding area
  37. 37. • The lack of pain permits pressure to be put directly onto the ulcer and results in nonhealing• A patient who walks on a plantar wound without limping must have neuropathy• (2)The next most common error is inappropriate management of infection• (3)Another common error is the failure to appreciate ischemic symptoms• (4)Finally, inappropriate wound debridement is another reason for slow healing or nonhealing of a diabetic foot ulcer
  38. 38. Neuropathic Foot Ulcer without Osteomyelitis(Wagner Grades 1, 2; University of Texas Grades 1a, 2a)• TCC or a removable Scotch cast boot• The TCC was recognized as the gold standard for off- loading a foot wound in the 1999 consensus statement on diabetic foot wounds by the American Diabetes Association• randomized, controlled trial in which Armstrong and colleagues compared three off-loading techniques and found that the TCC was associated with the shortest healing time
  39. 39. • In neuropathic ulcers with a good peripheral circulation, antibiotics are not indicated unless there are clear clinical signs of infection, including prominent discharge, local erythema, and cellulitis• The presence of any of these features in Wagners grade 1 or 2 ulcers would warrant reclassification in the University of Texas system to 1b or 2b. In such cases, deep wound swabs should be taken and broad-spectrum oral antibiotic treatment started Either an Amoxicillin–Clavulanic acid combination (Augmentin) or clindamycin. The antibiotic might need to be altered when sensitivity results become available
  40. 40. Neuroischemic Ulcers (Wagner Grades 1, 2; University of Texas Grades 1c, 1d)• Principles are similar to those for neuropathic ulcers with the following important exceptions:• Total contact casts are not usually recommended for management of neuroischemic ulcers although removable casts and pneumatic cast boots (Aircast) may be used• Antibiotic therapy is usually recommended for all neuroischemic ulcers• Investigation of the circulation (including noninvasive assessment and, when required, arteriography with appropriate subsequent surgical management or angioplasty) is indicated
  41. 41. Osteomyelitis (Wagner Grade 3; University of Texas Grades 3b, 3d)
  42. 42. Osteomyelitis (Wagner Grade 3; University of Texas Grades 3b, 3d)• Osteomyelitis is a serious complication of foot ulceration and may be present in as many as 50% of diabetic patients with moderate to severe foot infections• If the physician can probe down to bone in a deep ulcer, the presence of osteomyelitis is strongly suggested• Plain radiographs are indicated in any nonhealing foot ulcer and are useful in the diagnosis of osteomyelitis in more than two thirds of patients, although it should be kept in mind that the radiologic changes may be delayed
  43. 43. • MRI, bone scans, or an 111In-labeled white blood cell scan can be useful in diagnosing bone infection• Although the treatment of osteomyelitis is commonly surgical and involves resecting the infected bone, there have been reports of successful long-term treatment with antibiotics that treat the underlying bacterium, most commonly Staphylococcus aureus. Thus, agents such as clindamycin (which penetrates bone well) or flucloxacillin are often used• IV Tazocin 4.5g tds for inpatient could be used for severe cases, ciprofloxacin and Clindamycin is an alternative
  44. 44. Infection severity Clinical manifestationUninfected Wound lacking purulence or any manifestations of inflammationMild Presence of 2 or more manifestations of inflammation (purulence, or erythema, pain, tenderness, warmth, or induration), but any cellulitis/erythema extends 2 or less cm around the ulcer, and infection is limited to the skin or superficial subcutaneous tissues; no other local complications or systemic illness.Moderate Infection (as above) in a patient who is systemically well and metabolically stable but which has 1 or more of the following characteristics: cellulitis extending >2 cm, lymphangitic streaking, spread beneath the superficial fascia, deep-tissue abscess, gangrene, and involvement of muscle, tendon, joint or boneSevere Infection in a patient with systemic toxicity or metabolic instability (eg fever, chills, tachycardia, hypotension, confusion, vomiting, leukocytosis, acidosis, severe hyperglycaemia, or azotemia)
  45. 45. East and Antibiotic Usage Flow ChartNorth HertMild PO coamoxiclav 625mg TDS PO Clindamycin (if penicillin allergic) 300mg qds Duration of treatment 7-10 days (initially) Discharge and arrange out patient follow up with the Diabetic Podiatry Clinic (should be seen in the following week)Moderate iv coamoxiclav 1.2 gm TDS (plus clindamycin 600mg qds may be added if there is bone involvement on the advice of Consultant Diabetologist or Consultant Microbiologist) Or (if penicillin allergy) IV teicoplanin 400mg once daily (after 3 loading doses of 400mg 12 hrly) + IV metronidazole 500mg tds Modify antibiotics according to culture results and micro advice Duration of treatment 2-4 weeks, 6 weeks if osteomyelitis Start iv and switch to PO depending on the response If gram negative infection is likely/suspected, add gentamicin (monitor levels and renal functions)Severe IV Tazocin 4.5 g tds plus gentamycin stat IV Or penicillin allergic IV Teicoplanin 400mg od (after 3 loading doses of 400 mg 12 hourly ) + IV gentamycin 5mg/kg + IV metronidazole 500mg tds
  46. 46. Debridement
  47. 47. Gangrene (Wagner Grades 4, 5) It is in this area that the team approach is mostimportant, with close collaboration among the diabetes specialist, the vascular surgeon, and the radiologist
  48. 48. Gangrene (Wagner Grades 4, 5)• Gangrene or areas of tissue death is always a serious sign in the diabetic foot. However, localized areas of gangrene, especially in the toes, without cellulitis, spreading infection, or discharge, can occasionally be left to spontaneously autoamputate• The presence of more extensive gangrene requires urgent hospital admission; treatment of infection, often with multiple antibiotics; control of the diabetes, usually with intravenous insulin; and detailed vascular assessment
  49. 49. Charcots Neuroarthropathy• Charcots neuroarthropathy is a rare and disabling condition affecting the joints and bones of the feet• Permissive features for the development of this condition include the presence of severe peripheral neuropathy, together with autonomic dysfunction, with increased blood flow to the foot• The peripheral circulation is usually intact
  50. 50. • In the Western world, diabetes is the most common cause of a Charcots foot, and increased awareness of this condition can enable earlier diagnosis and treatment to prevent severe deformity and disability• The actual pathogenesis of the Charcot process is poorly understood• the patient with peripheral insensitivity and autonomic dysfunction with increased blood flow to the foot is vulnerable to unrecognized trauma that may be so trivial that the patient cannot recall the event
  51. 51. Diagnosis of Charcot• A unilateral swollen, hot foot is a patient with neuropathy must be considered to be Charcots foot until proved otherwise• Charcots arthropathy can be diagnosed in most patients by plain radiograph and a high index of suspicion. Radiographs might reveal bone and joint destruction, fragmentation, and remodeling
  52. 52. • Management of the acute phase involves immobilization, usually in a TCC• Evidence suggests that treatment with bisphosphonates, which reduce osteoclastic activity, can reduce swelling, discomfort, and bone turnover markers