Joint contractures sometimes develop and patients can be wheelchair-bound by the second decade. Dysarthric speech is common. No dysmorphic facial features are present.
[disorders.eyes.arizona.edu]
This is a slow, progressive disorder but most patients become wheelchair bound within 10-20 years after onset.
[bcm.edu]
At 22, he was wheelchair-bound. Neurological examination revealed bilateral plantar extensor responses, abolished Achilles reflexes, and finger to nose dysmetria.
[karger.com]