47: Neuropathic Bone Disease - Frush Flashcards
(18 cards)
define charcot foot
Charcot foot is a progressive condition characterized by joint dislocation, pathological fractures, and severe destruction of the pedal architecture
6 Ds of charcot foot on xray
Destruction Debris Dislocation Distention Disorganization Increased Density (subchondral sclerosis)
most common etiology
diabetes (anything that can cause neuropathy)
presence charcot in diabetics and in neuropathic pts
7.5% in Diabetic patients
29% in neuropathic patients
Mean age is 50.3 years
Neurotraumatic theory
Exaggerated overuse injury coupled with loss of protective sensation
Can be initiated by acute trauma or repetitive microtrauma
Lack of sensation allows continued tissue destruction resulting in fractures and dislocations
neurovascular theory
Vasomotor neuropathy in patients with intact blood flow
Arteriovenous shunting leads to excessive bone resorption and bone weakening
Contributes to fractures and dislocations with continued weightbearing
eichenholtz classification (stages)
0 - x ray normal, but high degree suspicion
I- acute red hot swollen, fragmentation on x ray
II- bony fragmentation becomes more solid
III - swelling gone, residual deformity
brodsky classification (location)
type 1: lisfranc's 2:choparts/subtalar 3A: ankle 3B: calcaneus 4: multiple regions 5: forefoot
s/s charcot
- red, hot, swollen foot
- temp difference (3-6 celsius)
- sensory neuropathy present
- pain doesnt match amount destruction
- bilateral 9-30% of the time
keys for diagnosis of charcot
- red, hot, edematous
- cortical fractures, periosteal reaction, joint debris, deformity, dislocation
- lack of break in skin
gold standard diagnosis osteomyelitis v. charcot
bone biopsy
- bone and cartilage debris embedded in synovium (charcot)
what test has highest sensitivity and specificity in detecting osteo in neuropathic foot
In111
best approach is to do a combined scan
+ Tec99
+ WBC scan
osteomyelitis
+ Tec 99
- WBC scan
charcot
- Tec 99
+ WBC scan
soft tissue infection
MRI for charcot
T1 - decreased
T2 - increased
STIR - high signal marrow edema
being able to probe to bone with metallic instrument is ____ positive for diagnosing osteomyelitis
89%
tx charcot based on stages
I - keep nwb in total contact cast or boot untiil ocnsolidationoccurs and/or temp stabilized
- may take months
II - increase protected weight bearing
III - custom orthotics or braces
