What is the recommended management for patients with sensory motor axonal Charcot-Marie-Tooth (CMT) disease?

Management of Sensory Motor Axonal Charcot-Marie-Tooth Disease

The recommended management for sensory motor axonal CMT disease should focus on rehabilitation, orthotic devices, and supportive care, as there are currently no approved disease-modifying therapies that can cure this condition. 1

Diagnostic Assessment

1. Imaging Studies:

   • Perform plain X-rays of foot and ankle, including anteroposterior (AP), medial oblique, and lateral projections
   • Use standing (weight-bearing) radiographs when possible to assess foot deformities and joint instability 2
   • Consider MRI when plain X-rays appear normal but clinical suspicion remains high 2

2. Clinical Evaluation:

   • Assess for peripheral neuropathy signs: distal muscle weakness and wasting, sensory loss in "glove and stocking" distribution, foot deformities, and digit contractures 2
   • Evaluate muscle strength, particularly in distal limbs
   • Assess balance, mobility, and functional capacity 3

Rehabilitation Approach

1. Exercise Program:

   • Implement an intensive rehabilitation protocol including:

     • Strengthening exercises targeting affected muscle groups
     • Stretching to maintain range of motion
     • Core stability training
     • Balance and resistance training
     • Aerobic exercises 4

   • Note: Evidence shows that exercise is effective in improving strength and general fitness, while stretching helps maintain range of motion 5

2. Frequency and Duration:

   • Intensive program: 2-4 hours/day, 5 days/week, for 3 weeks 4
   • Follow-up rehabilitation sessions every 3-4 months to maintain benefits, as improvements may be lost after one year 4

3. Specific Interventions for Functional Symptoms:

   • For functional tremor: Use alternative rhythmic movements, relaxation techniques, and gross rather than fine movements 6
   • For dystonia: Encourage optimal postural alignment, even weight distribution, and therapeutic resting postures 6
   • For functional weakness: Engage in tasks promoting normal movement and good alignment 6

Orthotic Management

1. Foot and Ankle Orthoses:

   • Provide footwear/orthoses that accommodate and support foot shape 2
   • For patients with deformity or joint instability, use below-the-knee customized devices for additional protection 2
   • Avoid below-ankle offloading devices (surgical shoes, postoperative sandals) as they provide inadequate immobilization 2

2. Assistive Devices:

   • Consider assistive devices (crutches, walker) to reduce weight-bearing on affected limbs when necessary 2
   • Use devices that promote mobility while preventing falls

Activity Modifications

1. Exercise Considerations:

   • Avoid high-impact activities that may increase risk of foot trauma 6
   • Consider aquatic exercise, cycle ergometry, or recumbent cycle ergometry to reduce weight-bearing 6
   • Regular inspection of feet for injuries, especially in areas with sensory loss 6

2. Monitoring:

   • Monitor skin temperature (temperatures elevated 4°F compared with the opposite foot may indicate inflammation) 6
   • Restrict activity during periods of inflammation to prevent complications 6

Surgical Interventions

Consider surgical intervention when:

• Foot/ankle joint instability is present
• Deformity with high risk of developing ulcers exists
• Pain cannot be adequately managed with conservative measures 2

Pharmacological Management

1. Not Recommended:

   • No specific pharmacological agents have shown significant benefit in CMT 7
   • Small trials of creatine monohydrate, purified bovine brain ganglioside injections showed no significant benefit 7

2. Supplementation:

   • Evaluate need for vitamin D and calcium supplementation, particularly during healing phases 2

Quality of Life Considerations

• Focus on interventions that improve physical function, as physical component scores are significantly related to leg power 3
• Address falls efficacy, as better scores are significantly related to faster habitual gait speed and strength 3

Monitoring and Follow-up

• Regular assessment of muscle strength, balance, and functional capacity
• Monitor for development of foot deformities and pressure points
• Evaluate for potential complications, including progression of neuropathy and development of ulcers

Important Considerations

• CMT is a genetic condition requiring long-term management strategies, distinct from diabetic Charcot neuropathy 2
• There are currently no curative medical treatments, making rehabilitation and orthotic management the cornerstone of treatment 5, 1
• Patient education about the progressive nature of the disease and importance of adherence to rehabilitation is essential

By implementing this comprehensive management approach, patients with sensory motor axonal CMT can experience improved strength, mobility, and quality of life despite the progressive nature of this condition.