CMT is a major focus for our practice at Cornell O&P. Ken Cornell CO has been a researcher/presenter for Orthotic management of CMT for over 20 years. In that time we have we have discovered many effective strategies for managing the unique issues for our CMT patients.
The disease itself:
CMT is officially HMSN, (hereditary motor sensory neuropathy) and there have been over 50 types identified so far. There are 3 common types and most are rare. 50% of patients will inherit type 1A, 20%-40% will inherit Type 2, and 10% will inherit Type X.
- Type 1A is progressive demyelinating disease characterized by slow motor conduction velocities.
- Type 2 patients undergo progressive axonal degeneration with low conduction amplitudes.
- Type X patients undergo axonal degeneration with secondary myelin changes (as males have only one X chromosome, they are more severely affected than females).
No matter which type you have, all patients with CMT undergo a very specific sequence of motor loss which creates the unique weaknesses and muscle imbalances that in turn create the deformities classic to CMT. Sensory deficits are always glove and stocking and eventually affect balance.
As for deformities, you are probably familiar with:
High arches for 80 % of you and low arches for 20% of you (both have plantar flexed first rays).
Ankles that roll out (hind foot inversion, calcaneal varus).
Painful calluses from weight bearing on mal-aligned skeletal segments.
Common issues for our CMT patients are:
- Poor balance.
- Chronic lateral ankle sprains.
- Foot drop.
- Progressing skeletal mal-alignment.
- Painful calluses and skin breakdown.
- Fatigue, as it takes much more energy to accomplish daily tasks.
- Most all CMT parents are very concerned about the outlook for their children and how the effects can be mitigated for them.