Diagnosis of Charcot-Marie-Tooth Disease (CMT)
A physical examination may confirm a high arch, claw toes, and muscle weakness. The Achilles (above the heel) and patellar (knee) tendon reflexes are weak or absent. Muscle strength testing can reveal atrophy and can be used to establish a baseline from which disease progression can be tracked.
Examining and testing several family members for signs of neuropathy can help establish a diagnosis of CMT.
Tests to Diagnose Charcot-Marie-Tooth Disease
Several tests are used to determine reduced muscle responses and nerve damage.
- A nerve conduction velocity (NCV) study measures the speed of nerve signal conduction. A patient with CMT1 has slower than normal NCV readings due to myelin deterioration.
- Electromyography (EMG) records muscle activity during voluntary contractions and when electrically stimulated. It also determines if muscles are receiving neurological stimulation.
- Magnetic resonance imaging (MRI scan) establishes whether the nerves in the spinal cord have been affected (rare).
- A DNA blood test can identify some types of the disorder.
EMG and NCV tests, which can be used in combination, are often referred to as EMG/NCV studies.
Treatment for Charcot-Marie-Tooth Disease
Treatment for CMT depends on the severity of symptoms and the age of the patient. The goal is to make the patient comfortable and increase the ability to perform daily activities.
Orthotics to Treat Charcot-Marie-Tooth Disease
Orthotics may be prescribed to improve mobility and gait, provide support, and decrease risk of injury.
In the early stages of CMT, foot deformities can be corrected with braces that help maintain proper foot and leg alignment and reduce the risk of sprains. Splints are used on the forearm and hand.
If muscle weakness in the leg causes the foot to drag while walking, the patient can be fitted with a special brace that holds the foot at a 90-degree angle to the leg. If the entire lower leg is severely weakened, braces that extend above the knee and attach to the stronger muscles of the upper leg can provide adequate support.
Custom-made shoes and/or inserts can improve gait and redistribute the weight of the body on the foot.
Physical Therapy to Treat Charcot-Marie-Tooth Disease
Physical therapy helps maintain muscle strength and endurance in the affected limbs.
Surgery for Charcot-Marie-Tooth Disease
If rigid foot deformity prevents the foot from being manipulated into proper alignment with a brace, surgery may help. The goal of surgery is to help the foot and leg function as normally as possible, so the patient can walk with minimal difficulty. When foot muscles are too weak to hold the bones in proper position, the foot bones can be surgically fused to provide stability and support.
Charcot-Marie-Tooth Disease Prognosis
Foot and hand deformity and walking problems are lifelong disabilities. Mental function and longevity usually are not affected, however, and most people with CMT lead productive lives.