Louise Wade MSN, RN
According to the American Diabetes Association [ADA] (2013),
Type 2 diabetes involves severe systemic complications, which
occur due to uncontrolled elevated glycemic levels such as
nephropathy, neuropathy, retinopathy, foot complications,
heart disease, stroke and many other devastating health
problems.
Key facts (World Health Organization)
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347 million people worldwide have diabetes
In 2004, an estimated 3.4 million people died from consequences
of high fasting blood sugar
More than 80% of diabetes deaths occur in low- and middleincome countries
WHO projects that diabetes will be the 7th leading cause of death
in 2030 (4).
Healthy diet, regular physical activity, maintaining a normal body
weight and avoiding tobacco use can prevent or delay the onset of
type 2 diabetes.
(who.org, 2013)
What are common consequences of diabetes?
Over time, diabetes can damage the heart, blood vessels, eyes, kidneys, and nerves.
Diabetes increases the risk of heart disease and stroke. 50% of people with diabetes
die of cardiovascular disease (primarily heart disease and stroke).
Combined with reduced blood flow, neuropathy (nerve damage) in the feet
increases the chance of foot ulcers, infection and eventual need for limb
amputation.
Diabetic retinopathy is an important cause of blindness, and occurs as a result of
long-term accumulated damage to the small blood vessels in the retina. One
percent of global blindness can be attributed to diabetes.
Diabetes is among the leading causes of kidney failure.
The overall risk of dying among people with diabetes is at least double the risk of
their peers without diabetes.
High blood sugar (glucose) that circulates in the bloodstream
instead of being absorbed into cells damages nerves and blood
vessels throughout the body and, ultimately, the major organs
such as the kidneys and heart. It has been said that there isn’t a
system in the body that isn’t affected by diabetes.
Peripheral neuropathy is the result of nerve damage from
uncontrolled blood glucose levels and often involves weakness,
numbness and pain of the affected extremity (mayoclinic.org, 2013).
Neuropathy can also lead to a condition known as Charcot foot, which
is a condition affecting the bones, joints, and soft tissue of the foot and
ankle. If not diagnosed correctly during the acute phase, Charcot may
result in amputation of the affected limb; therefore, it is essential for
health care providers to be familiar with the signs and symptoms and
refer to the appropriate specialist (Rogers et al, 2013).
The etiology of neuropathy is the destructive or dysfunction of
peripheral nerves, which are damaged by uncontrolled elevated
blood glucose levels. Peripheral neuropathy causes significant
issues such as nonhealing wounds, major infections,
amputations, and a condition known as Charcot foot that
involves the soft tissue and bones of the foot and ankle and
leads to permanent deformities.
In general, there are three types of neuropathy: sensory,
autonomic and motor. Sensory neuropathy is the most
common, affecting how we perceive temperature, texture and
pain. Autonomic neuropathy affects nerves involved in
involuntary actions in the body such as emptying of the
stomach, intestines and bladder. Motor neuropathy, affecting
the nerves involved in movement, is rare in diabetes.
(virginiamason.org, 2014).
•Distal neuropathy affects the hands and feet and is the most
common form of diabetic neuropathy. It usually affects both
hands or both feet, but may affect only one hand or foot.
Foot problems
Nerve and blood vessel damage – causing a lack of pain sensation and
decreased blood flow – can result in serious foot problems. People with
diabetes are particularly at risk for foot ulcers and infections: they may not
know, for example, that an injury has occurred to the foot. And a lack of
blood flow may slow the healing process. In severe cases, sores may never
heal, leading to gangrene and amputation.
For people with diabetes, it is important always to wear shoes and to
inspect your feet every day, including the bottoms of your feet, for sores
and infections.
CMT is just one kind of neuropathy (also called peripheral
neuropathy). These names simply mean that the peripheral
nerves are damaged. There are many other causes of neuropathy
besides CMT, including the most common cause—diabetes.
Charcot-Marie-Tooth is named after three physicians who were
the first to describe it in 1886: Jean-Martin Charcot, Pierre
Marie, and Howard Henry Tooth (cmtausa.org, 2010).
Charcot foot is a serious and potentially life-threatening
complication associated with diabetes and continues to
challenge the most experienced practitioner. Charcot is
characterized by various degrees of bone, joint, soft tissue, foot
and often ankle involvement and is secondary to underlying
neuropathy, trauma, and perturbations of bone metabolism and
involves inflammation during the acute phase (Rogers et al,
2011). While the exact etiology of Charcot foot is unknown, the
primary causative issue is believed to be the result of diabetic
neuropathy.
•Charcot joint may occur if the bones in the feet develop
fractures and the foot becomes misaligned. The condition can
be painless because nerves were damaged from diabetes before
the fracture developed. The foot or feet may then lose muscle
support, eventually becoming deformed.
Progression of Charcot
Charcot arthropathy most likely results as a combination of the
following two theories:
Neurotraumatic Theory
The process begins with an unperceived trauma or injury to an insensate
joint. The sensory neuropathy renders the patient unaware of the osseous
destruction that occurs with ambulation. This microtrauma leads to
progressive destruction and damage to bone and joints.
Neurovascular Theory
The underlying condition leads to the development of autonomic
neuropathy, causing the extremity to receive increased blood flow. This
results in a mismatch in bone destruction and synthesis, leading to
osteopenia.
Because of the decrease in sensation, the patient usually does
not realize they have the condition. They continue walking on
the untreated foot, ultimately causing the condition to worsen.
Neuropathic patients who have a tight Achilles tendon are also
prone to developing Charcot foot.
Jones Fracture (5th Metatarsal Stress Fracture)
Obesity
 Obesity is a strong risk factor for peripheral
neuropathy Charcot arthropathy of weight-bearing
joints.
Risk Factors Cont’d
 The trigger for Charcot foot can be a sprain or twisted
ankle that goes unnoticed because of reduced feeling
from nerve damage.
 If the person continues to place pressure on the foot
through walking, the injury can worsen and could lead
to dislocation or fractures in one or more bones of the
foot or ankle.
There may be several types of injury
associated with this complication
including subluxation, dislocation and
other deformities but the classic sign is
the midfoot collapse, described as a
“rocker-bottom” foot, which is a
permanent deformity unless surgically
repaired.
"Charcot foot occurs in less than one percent of the entire
diabetes population and in only about one-third of those with
neuropathy” (Frykberg, 2010).
According to the American Diabetes Association, 60–70% of
people with diabetes develop peripheral nerve damage that can
lead to Charcot foot and about 0.5% of these patients develop
the condition. In most cases, onset occurs after the age of 50,
and after the patient has had diabetes for 15 to 20 years (Peng &
Swierzerswki, 2011).
In the most common kinds of CMT, symptoms usually
begin before the age of 20 years. They may include:
•Foot deformity (very high arched feet); May be severe
•Foot drop (inability to hold foot horizontal);
•“Slapping" gait (feet slap on the floor when walking
because of foot drop);
•Loss of muscle in the lower legs, leading to skinny calves;
•Numbness in the feet;
•Difficulty with balance;
•Later, similar symptoms also may appear in the arms and
hands.
Symptoms of Charcot foot include the following:
•Dislocation of the joint
•Heat
•Insensitivity in the foot
•Instability of the joint
•Redness
•Strong pulse
•Swelling of the foot and ankle (caused by synovial fluid
that leaks out of the joint capsule)
•Subluxation (misalignment of the bones that form a
joint)
1.Development (Acute Phase) - Inflammation and radiographic
visibility of changes. Possible debris formation, fragmentation,
subluxation, dislocation, and distention.
2.Coalescence - Decreased inflammation. Absorption of debris
and fusion of fragments. Progression slows and transitions into
remodeling.
3.Remodeling - Remodeling and consolidation. Structural
deformity is likely present and can lead to skin breakdown,
infection, and amputation.
Acute Phase
Coalescence Stage
Remodeling Stage
According to Rogers et al (2011), “the Charcot foot in diabetes
poses many clinical challenges in its diagnosis and
management. Despite the time that has passed since the first
publication on pedal osteoarthropathy in 1883, we have much to
learn about the pathophysiology, and little evidence exists on
treatments of this disorder.”
Charcot foot can cause various complications, including:
•Calluses
•Foot ulcers, especially if the foot is deformed or if the condition
is not caught in its early stages
•Bony protrusions (these have potential to become infected if
rubbed on the inside of the shoe for an extended period)
•Osteomyelitis (bone infection)
•Inflammation of the joint membranes
•Blood vessel and/or nerve compression
•Loss of sensation in the foot
•Loss of function in the foot
Other potential complications include the following:
•Progressive inability to walk from weakness, balance problems,
and/or orthopedic problems;
•Progressive inability to use hands effectively;
•Injury to areas of the body that have decreased sensation
(i.e. Achilles tendon tear or rupture).
Foot Ulcerations
Calluses
Bony Protrusions
Identifying this condition in its early stages is critical to
successful treatment. Patients should see a podiatrist at the
first sign of symptoms. Diagnosis can sometimes be difficult
because this condition can mimic other conditions like cellulitis
or deep venous thrombosis, and because diagnosis of a Charcot
fracture cannot be made definitively until bone changes occur.
“The initial manifestations of the Charcot foot are frequently
mild in nature, but can become much more pronounced with
unperceived repetitive trauma. Diagnostic clinical findings
include components of neurological, vascular, musculoskeletal,
and radiographic abnormalities” (Rogers et al, 2011).
Typical clinical findings include a markedly swollen, warm, and
often erythematous foot with only mild to modest pain or
discomfort. Acute local inflammation is often the earliest
sign of underlying bone and joint injury
Diagnostic recommendations for active Charcot
The diagnosis of active Charcot foot is primarily based on history and
clinical findings but should be confirmed by imaging.
Inflammation plays a key role in the pathophysiology of the Charcot
foot and is the earliest clinical finding.
The occurrence of acute foot/ankle fractures or dislocations in
neuropathic individuals is considered active CN because of the
inflammatory process of bone healing, even in the absence of
deformity.
X-rays should be the initial imaging performed, and one should look
for subtle fractures or subluxations if no obvious pathology is visible.
MRI or nuclear imaging can confirm clinical suspicions in the
presence of normal-appearing radiographs.
CMT usually gets worse, slowly, with age; rapid progression is
rare, and should motivate a prompt re-evaluation. The problems
with weakness, numbness, difficulty with balance, and
orthopedic problems can progress to the point of causing
disability. Pain can be an issue, as a direct result of the
neuropathy (neuropathic pain) and as consequence of
orthopedic problems.
Affected joints may be fully healed within 1-2 years of
treatment, however lifelong care should be taken to prevent
recurrence. This includes preventing injury, noting temperature
changes, checking feet regularly, reporting trauma, and
receiving professional foot care as necessary.
Patients should check feet daily for any changes including
injuries, cracks or dryness, warmth, infections, decreased
sensation, etc.
There are several ways to treat Charcot foot. The main goal is
to stabilize the joints. Although there are no known
treatments that will stop or slow down the progression of CMT,
but the CMTA is funding research to find these treatments.
Recovery times can be up to eight weeks or longer in the acute
stage, during which time patients will be required to be nonweight bearing.
Non-surgical treatment options include:
•Immobilization
•Custom shoes and bracing
•Use of crutches, casts, wheelchair used to protect foot
•Limiting activities that cause the condition
Although surgical treatment is an option, treatment is primarily
nonoperative. Conservative treatment of Charcot arthropathy
relies on halting the destructive phase of progression, and then
protecting and supporting the joints throughout the healing
process.
Physical therapy, occupational therapy, and physical activity
may help maintain muscle strength and improve independent
functioning.
Treatment plans can be broken into two phases, acute and
postacute
Acute Treatment Phase (Onset until Charcot is inactive, 36 months after onset)
Immobilization to prevent further destruction. The medical
treatment of CN is aimed at offloading the foot, treating bone
disease, and preventing further foot fractures.
**Offloading at the acute active stage of the Charcot foot is the
most important management strategy and could prevent the
progression to deformity**
Immobilization usually is accomplished by casting. Total
contact casts have been shown to allow patients to ambulate
while preventing the progression of deformity.
CROW is an acronym for Charcot Restraint Orthotic Walker. This orthosis is prescribed
for patients who have foot ulcers or insensate feet (can’t feel). This is an orthosis that is
clamshell in design and covers the entire foot and calf of the leg, resembling a ski boot
(See Figure 1). While it is somewhat big and bulky, the CROW gives tremendous support
by preventing foot and ankle movement. It is fully padded on the inside. A shoe is not
worn with this orthosis.
Surgical treatment of Charcot arthropathy of the foot and ankle is
based primarily on expert opinion. Surgery has generally been advised
for resecting infected bone (osteomyelitis), removing bony
prominences that could not be accommodated with therapeutic
footwear or custom orthoses, or correcting deformities that could not
be successfully accommodated with therapeutic footwear, custom
ankle-foot orthoses, or a Charcot Restraint Orthotic Walker
Surgery has generally been avoided during the active inflammatory
stage because of the perceived risk of wound infection or mechanical
failure of fixation.
Surgical Repair of Charcot
(End of acute phase through 1-2 years after onset)
Following acute treatment phase, it is necessary to protect
the foot throughout the remainder of the healing process.
Protection methods include:
Accommodative footwear with rigid soles and shanks
Rocker bottoms to relieve stress on plantar ulcers
Accommodative foot orthoses to protect insensate feet
Orthopedic equipment (such as braces, inserts, or
orthopedic shoes) may make it easier to walk.
Custom Fit Orthotics
Although Charcot is a devastating complication of diabetic
peripheral neuropathy and may affect a person’s physical
appearance and their ability to work, it does not have an affect
on their mental capabilities. Patients are often left with feelings
of depression, guilt from financial strains, and isolation.
Referrals for counseling and other resources are to be
considered.
Patients may qualify for social security disability benefits and
should consider applying as soon as they have been diagnosed.
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from http://www.diabetes.org/living-with-diabetes/complications/
Charcot-marie-tooth-association: What is charcot-marie-tooth (cmt)? . (2010,
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70&Itemid=159
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Rogers, L., Frykberg, R., Armstrong, D., Boulton, A., Edmonds, M., Ha Van, G., &
Hartemann, A. (2011). The Charcot foot in diabetes. Diabetes Care, 34(9),
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