The multiple phenotypes of Arthrogryposis multiplex congenita with reference to the neurogenic variant

Abstract

Arthrogryposis can occur in isolation or as part of a syndrome. Amyoplasia, the commonest type of arthrogryposis, has been well described in literature, but neurogenic arthrogryposis, a rarer but significantly heterogeneous variant, has not. We conducted a single-centre, 10-year retrospective study of all children with arthrogryposis at the Dubowitz Neuromuscular Centre, London, UK to describe the various phenotypes of arthrogryposis with special reference to the neurogenic variant including presentation, associated features and long-term outcome. Twenty-seven children with arthrogryposis were identified (13 males) and 25 survivors followed-up for 6.4 ± 2.32yrs. Perinatal history, presenting clinical features, investigations, final diagnosis and long-term outcomes were recorded. All four limbs were involved in 19 (ankles > wrists > elbows) whilst 8 had isolated upper (UL) or lower limb (LL) involvement. Twelve children had neurogenic arthrogryposis confirmed by a combination of clinical examination, EMG and/or muscle pathology. CK was normal in all children with neurogenic arthrogryposis. Three children in this cohort had abnormal brain MRIs and global developmental delay. Long-term follow up did not show deterioration of muscle power in any of our 12 children with neurogenic arthrogryposis, although contractures lead to temporary worsening of function ability in some ( n = 3). Most children improved with physiotherapy and well-fitted orthoses. Our study suggests that neurogenic arthrogryposis is usually a non-progressive disorder and in the absence of concomitant brain abnormalities, allows the clinician to offer an optimistic prognosis to the family.