Musculoskeletal and dermatological manifestations of Diabetes Flashcards
What is the most common dermatological and MSK complication of diabetes
Diabetic foot ulcer
What is the lifetime risk of a diabetic foot ulcer
up to 25%
How do diabetic foot problems arise
secondary to neuropathy and peripheral arterial disease
What is the usual precipitating event for diabetic foot ulcers
trauma
How can sensory neuropathy be detected
10g monofilament
How is the filament used
it is pressed against the plantar aspects of the first ad fifth toes, the first, third and fifth metatarsal heads and the plantar surface of the heel
When should peripheral arterial disease be suspected
in patients with intermittent claudication
cool temperature
absence of hair and
presence of foot ulcers
What is the normal ABPI
1.0-1.3
How do we calculate ankle-brachial pressure index
Measuring the systolic blood pressure in the brachial, posterior tibial and doornails pedis arteries. The highest of four measurements in the ankle and feet is divided by the highest of the brachial measurements
What does an ABPI over 1.3 suggest
the presence of calcified vessels which is common in diabetes
How are diabetic foot infections diagnosed
At least two of the following: erythema, warmth, swelling, tenderness
Pus coming out of an ulcer site or a nearby sinus tract
What is a mild infection
involvement of the skin or superficial subcutaneous tissues
erythema, warmth, swelling, tenderness,
purulence and cellulitis extending for less than 2cm around the ulcer
What is a moderate infection
more extensive infection or involvement of deeper tissues
cellulitis extending >2cm around an ulcer, lymphangitic streaking, deep tissue abscess, gangrene (necrosis) or involvement of muscle, tendon, joint or bone
What is a severe infection
signs of systemic toxicity or metabolic instability
fever, chills, tachycardia, tachypnoea, hypotension, confusion, vomiting and blood tests showing severe hyperglycaemia, leukocytosis, metabolic acidosis and raised urea and creatinine
What causes gangrene (necrosis)
Ischaemia and is classified as wet or dry
What causes ischaemia in wet gangrene
septic vasculitis associated with soft tissue infection
Tissues are black, brown or grey, moist and often malodorous
What causes ischaemia in dry gangrene
peripheral arterial disease
Tissues are black , hard and mummified
Clear line between necrosis and viable tissue
What do a lot of patients with diabetic foot ulcers also have
osteomyelitis
What factors increase the likelihood of osteomyelitis in patients with diabetic foot ulcers
Visible bone or the ability to probe to bone
ulcer size >2x2cm
ulcer depth >3mm
Ulcer duration longer than 1-2 weeks
What should blood tests include
FBC U&E ESR CRP Blood glucose HbA1c
What are often the causative organisms of superficial ulcers
aerobic Gram positive cocci: staph aureus strep agalaciae strep pyogenes coagulase negative staphylococci
What are often the causative organisms of deep, chronic ulcers
gram-negative bacilli:
pseudomonoas aureginosa
proteus mirabilis
If an ulcer has extensive local inflammation and signs of systemic toxicity, what should be presumed
anaerobic organisms as well as pathogens in deep chronic ulcers
What imaging must be performed in diabetic foot infections and why
Foot radiograph to look for osteomyelitis
What should be performed in patients with one or more of the risk factors for osteomyelitis and whose radiographs are indeterminate for osteomyelitis
MRI
What can be seen in radiograph for chronic osteomyelitis
cortical erosion periosteal reaction mixed bony lucency sclerosis sequestra
What does MRI identify in osteomyelitis
bone marrow oedema
soft tissue inflammation
cortical destruction
What does a duplex US allow
anatomical localisation of arterial stenoses and assessment of blood flow haemodynamics
What is the gold standard of diagnostic evaluation for peripheral arterial disease
angiography
What does the management of a diabetic foot ulcer include
Attentive wound management and debridement antibiotic therapy relief of pressure on the ulcer revascularisation glycaemic control
When should prompt surgical debridement occur
in the presence of a large area of infected sloughy tissue
infections complicated by abscess
crepitus with gas in the soft tissues on Xray
purplish discolouration of the skin
extensive bone or joint involvement
What sort of devices can be used to relieve pressure on the ulcer
removable cast walkers
half shoes
total contact casts
What are some factors that have been suggested to contribute to the pathogenesis of neuropathic arthropathy
peripheral neuropathy and lack of proprioception may result in ligamentous laxity
Autonomic neuropathy results in vasomotor changes
Exaggerated local inflammatory response to trauma
How might patients with Charcot arthropathy present
a sudden onset of unilateral warmth, redness and oedema over the foot or ankle
slowly progression arthropathy with insidious swelling over months or years, collapse of the arch of the midget and bony prominences and deformities
What are some abnormalities that might be seen on a good radiograph
Soft tissue swelling
loss of joint space
osteopenia
forefoot: osteolysis of the phalanges, bone resorption, partial or complete disappearance of the metatarsal head
midfoot and hindfoot: osseous fragmentation, sclerosis, new bone formation, subluxation and dislocation
What might a radioisotope scan show in Charcot arthropathy
Increased uptake in neuropathic arthropathy
How is acute onset Charcot arthropathy treated
avoidance of weight bearing on the affected joint until oedema and erythema have resolved (minimum of 8 weeks)
What is limited joint mobility commonly associated with
thickening and waxiness of the skin on the dorsal surface of the fingers
What does the prayer sign test help to identify
contractures in the metacarpophalangeal proximal and distal interphalangeal joints
How can limited joint mobility be treated
Tight glycaemic control
physio
stop smoking
injection of corticosteroid into the palmar tendon sheath
What is diabetic muscle infarction characterised by
an acute or subacute onset of muscle pain, swelling and tenderness, usually in the muscles of the thigh and calf
What does a definitive diagnosis of diabetic muscle infarction require
biopsy of the affected area of muscle to demonstrate ischaemic encores and exclude infection
What are the most common dermatological manifestations of diabetes
protracted wound healing and skin ulcerations
How does diabetic dermopathy begin
erythematous areas that evolve into areas of circular hyper pigmentation
Who are more likely to develop diabetic dermopathy
elderly men
What is a dermatological sign of insulin resistance
acanthosis nigricans
What is diabetic sclerodactyly characterised by
thickening and waxiness of the skin on the doors of the gingers and may be associated with limited joint mobility
