Monarch Disease Ontology id MONDO_0018419 (autosomal recessive spastic paraplegia type 67) is an extremely rare, complex hereditary spastic paraplegia characterized by an infancy or childhood onset of global developmental delay and progressive spasticity with tremor in the distal limbs, increased deep tendon reflexes and extensor plantar responses, which may be associated with mild intellectual disability. Additional features include muscle wasting and cerebellar abnormalities. Also known as: SPG67.