Ulcerated 3

Skin & Subcutaneous Tissue

{"ops":[{"insert":"Diagnosis and reasoning"},{"insert":"\n","attributes":{"header":1}},{"insert":"This middle aged man has presented with a chronic foot ulcer. Given the history of diabetes, this is very likely neuropathic, ischemic, or neuro-ischemic in origin. A through clinical evaluation is key to determining the exact etiology. \n\nThe first step should be careful inspection of the ulcer. This shows the ulcer to be painless, with a \u0027punched out\u0027 morphology; and most importantly, it is located over a pressure point of the foot. This strongly favors a neuropathic origin. Note also that ischemic ulcers are painful, tender, and often superficial; in addition, the surrounding skin typically appears unhealthy.\n\nThe next step should be examination of the affected extremity with regard to neurological and vascular status. This patient shows a \u0022stocking\u0022 distribution of sensory impairment in both lower limbs, with loss of ankle reflexes. This is strongly suggestive of distal symmetric polyneuropathy (a form of diabetic peripheral neuropathy). The arterial system appears to be normal, as all peripheral pulses are present, and the ankle-brachial pressure index (ABI) is within normal parameters.\n\nThus, the clinical diagnosis is a neuropathic ulcer. \n\nThe presence of peripheral (large fibre) neuropathy can be established by the 10g Semmes-Weinstein Monofilament test. Inability to perceive the monofilament in 4 or more sites out of 10 (as in this patient) is indicative of loss of protective sensation.\n\nNeuropathic ulcers are typically deep, potentially extending down to the level of the foot bones. Thus, screening him for underlying osteomyelitis via a foot x-ray is justifiable (but negative in this case). \n\nEvaluation of vascular status is not indicated, as there are no clinical findings suggestive of arterial insufficiency. In addition, wound cultures are not routinely recommended, as all ulcers are contaminated with commensals.\n\nProper debridement and saline dressings will aid the healing process. Antibiotics are only indicated if wound infection is present. Note also that graduated pressure stockings are used in the treatment of venous ulcers.\nDiscussion"},{"insert":"\n","attributes":{"header":1}},{"insert":"Up to 15% of patients with diabetes will develop a foot ulcer at some point in their lives. In addition, nonhealing foot ulcers precede almost 85% of lower-limb amputations.\n\nDiabetic neuropathy is the most common underlying etiology. Sensory neuropathy causes loss of protective sensation, resulting in repetitive stress that eventually leads to ulcer formation; autonomic neuropathy results in reduced sweating, thereby causing dry skin and fissure formation, and predisposing the skin to infection. Ischemia secondary to peripheral vascular disease may also result in ulceration, although this is more often a contributory factor than the sole cause. Foot deformities such as bunions, calluses and hammertoes (which are common in diabetic patients) may lead to focal areas of high pressure, thereby contributing to ulcer formation.\n\nIn most cases, the causative etiology or etiologies can be determined clinically. The investigative workup should be tailored to the clinical findings, and include neurological, circulatory and radiological assessment as necessary.\n\nThe neurological assessment should include determination of vibration thresholds by means of a 128-Hz tuning fork, and detection of protective sensation via a 10 gauge monofilament An x-ray should be ordered in all ulcers which are deep, infected, or non-healing, to exclude osteomyelitis. CT and MRI scans may be considered if a plantar abscess is suspected.\n\nThe principles of management include treatment of the ulcer, treatment of the underlying etiology, and prevention of further ulcer formation. \n\nWound debridement is the first step in treating the ulcer. This involves removal of all necrotic tissue, peri-wound callus, and foreign bodies, until viable tissue remains. This will decrease the risk of infection and reduce peri-wound pressure (which can otherwise impair healing and normal wound contraction). Following debridement, a moist dressing should be applied in order to promote wound healing. Note that dressings should not be changed overly frequently, as this will impede wound healing.\n\nAs neuropathic ulcers frequently occur at pressure points, offloading (i.e. effective redistribution and relief of pressure) is a critical element of the management. Techniques in this regard include the use of casts or boots, and felted foam dressings. In certain patients, skin grafting may be considered once the ulcer has healed, and healthy granulation tissue is present. Note that the effectiveness of skin replacement therapy in the management of diabetic ulcers is still unestablished.\n\nAntibiotics should be prescribed if the ulcer appears to be infected. If underlying osteomyelitis is present, aggressive resection of infected bone and joints followed by 4 to 6 weeks of culture-directed antibiotic therapy may be required.\n\nTreatment of contributory conditions includes proper glycemic control and detection and treatment of ischemia, if present. Most ulcers with an ischemic component will not heal completely until the ischemia has resolved. In certain patients, amputation may have to be performed as a last resort, especially if the combination of deep infection and ischemia is present.\n\nOnce the ulcer has healed, it is important to maintain skin integrity in order to prevent recurrence. This is done by recognition of risk factors, and educating the patient about proper foot care. Important elements with regard to foot care include daily foot inspection, gentle soap and water cleansing, application of skin moisturizer and proper trimming of nails. It is also critical to educate the patient about proper footwear. Their shoes should protect the feet, fit well and be deep and wide enough to prevent rubbing.\nTake home messages"},{"insert":"\n","attributes":{"header":1}},{"insert":"1. While diabetic foot ulceration is predominantly neuropathic in origin, there is often a contributory ischemic component.\n2. A deep or non-healing ulcer should raise suspicion of underlying osteomyelitis.\n3. Proper foot care, footwear, and patient education are essential to prevent dire sequelae such as amputation.\nReferences"},{"insert":"\n","attributes":{"header":1}},{"insert":"ARMSTRONG DG, BOULTON AJM, BUS SA. Diabetic Foot Ulcers and Their Recurrence. N Engl J Med [online] 2017 Jun 15, 376(24):2367-2375. Available from: http:\/\/www.ncbi.nlm.nih.gov\/pubmed\/28614678"},{"insert":"\n","attributes":{"list":"ordered"}},{"insert":"BRENNAN MB, HESS TM, BARTLE B, COOPER JM, KANG J, HUANG ES, SMITH M, SOHN MW, CRNICH C. Diabetic foot ulcer severity predicts mortality among veterans with type 2 diabetes. J Diabetes Complications [online] 2017 Mar, 31(3):556-561. Available from: http:\/\/www.ncbi.nlm.nih.gov\/pubmed\/27993523"},{"insert":"\n","attributes":{"list":"ordered"}},{"insert":"JEFFCOATE WJ, VILEIKYTE L, BOYKO EJ, ARMSTRONG DG, BOULTON AJM. Current Challenges and Opportunities in the Prevention and Management of Diabetic Foot Ulcers. Diabetes Care [online] 2018 Apr, 41(4):645-652. Available from: http:\/\/www.ncbi.nlm.nih.gov\/pubmed\/29559450"},{"insert":"\n","attributes":{"list":"ordered"}},{"insert":"LIM JZ, NG NS, THOMAS C. Prevention and treatment of diabetic foot ulcers. J R Soc Med [online] 2017 Mar, 110(3):104-109. Available from: http:\/\/www.ncbi.nlm.nih.gov\/pubmed\/28116957"},{"insert":"\n","attributes":{"list":"ordered"}},{"insert":"BOULTON ANDREW J.M.. The diabetic foot. Medicine [online] 2019 February, 47(2):100-105. Available from: doi:10.1016\/j.mpmed.2018.11.001"},{"insert":"\n","attributes":{"list":"ordered"}},{"insert":"BARWELL ND, DEVERS MC, KENNON B, HOPKINSON HE, MCDOUGALL C, YOUNG MJ, ROBERTSON HMA, STANG D, DANCER SJ, SEATON A, LEESE GP, SCOTTISH DIABETES FOOT ACTION GROUP.. Diabetic foot infection: Antibiotic therapy and good practice recommendations. Int J Clin Pract [online] 2017 Oct. Available from: http:\/\/www.ncbi.nlm.nih.gov\/pubmed\/28892282"},{"insert":"\n","attributes":{"list":"ordered"}},{"insert":"TONE A, NGUYEN S, DEVEMY F, TOPOLINSKI H, VALETTE M, CAZAUBIEL M, FAYARD A, BELTRAND \u00c9, LEMAIRE C, SENNEVILLE \u00c9. Six-week versus twelve-week antibiotic therapy for nonsurgically treated diabetic foot osteomyelitis: a multicenter open-label controlled randomized study. Diabetes Care [online] 2015 Feb, 38(2):302-7. Available from: http:\/\/www.ncbi.nlm.nih.gov\/pubmed\/25414157"},{"insert":"\n","attributes":{"list":"ordered"}},{"insert":"NELSON EA, O\u0027MEARA S, GOLDER S, DALTON J, CRAIG D, IGLESIAS C, DASIDU STEERING GROUP.. Systematic review of antimicrobial treatments for diabetic foot ulcers. Diabet Med [online] 2006 Apr, 23(4):348-59. Available from: http:\/\/www.ncbi.nlm.nih.gov\/pubmed\/16620262"},{"insert":"\n","attributes":{"list":"ordered"}},{"insert":"L\u00e1ZARO-MART\u00edNEZ JL, ARAG\u00f3N-S\u00e1NCHEZ J, GARC\u00edA-MORALES E. Antibiotics versus conservative surgery for treating diabetic foot osteomyelitis: a randomized comparative trial. Diabetes Care [online] 2014, 37(3):789-95. Available from: http:\/\/www.ncbi.nlm.nih.gov\/pubmed\/24130347"},{"insert":"\n","attributes":{"list":"ordered"}}]}

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