SCAPULOPERONEAL SPINAL MUSCULAR ATROPHY
OVERVIEW
A scapuloperoneal spinal muscular atrophy(SPSMA) is a rare autosomal dominant genetic motor neuron disease characterized by predominantly motor axonal peripheral neuropathy manifesting with progressive scapuloperoneal spinal muscular atrophy and weakness, laryngeal palsy, congenital absence of muscles, and, in some, skeletal abnormalities. The scapuloperoneal spinal muscular atrophy is caused by heterozygous mutation in the TRPV4 gene on chromosome 12q24.[1] Congenital distal spinal muscular atrophy and hereditary sensory and motor neuropathy are allelic disorders with overlapping features.
INHERITANCE
The transmission pattern of scapuloperoneal spinal muscular atrophy(SPSMA) is consistent with autosomal dominant inheritance.[2]
PREVALENCE
The prevalence of scapuloperoneal spinal muscular arophy(SPSMA) is < 1/1000000.
AGE OF ONSET
Childhood, Infancy, Neonatal.
CLINICAL FEATURES
- Congenital Absence of muscles, weakness and atrophy of the proximal upper and lower muscles
- Progressive scapuloperoneal atrophy
- Laryngeal Palsy resulting in hoarse voice and respiratory stridor
- Progressive distal weakness and amyotrophy
- Torticollis
- Congenital Hip Dysplasia
- Fascial Muscle Paresis, Neck Flexor weakness
- Abducens weakness
- Wide based gait, hyper-lordosis and Gowers sign
- Small hands and one arm or leg shorter than other
- ↑ Deng HX, Klein CJ, Yan J, Shi Y, Wu Y, Fecto F; et al. (2010). "Scapuloperoneal spinal muscular atrophy and CMT2C are allelic disorders caused by alterations in TRPV4". Nat Genet. 42 (2): 165–9. doi:10.1038/ng.509. PMC 3786192. PMID 20037587.
- ↑ DeLong R, Siddique T (1992). "A large New England kindred with autosomal dominant neurogenic scapuloperoneal amyotrophy with unique features". Arch Neurol. 49 (9): 905–8. doi:10.1001/archneur.1992.00530330027010. PMID 1520078.