173rd ENMC International Workshop: congenital muscular dystrophy outcome measures 5-7 March 2010, Naarden, The Netherlands.

The 173rd ENMC/TREAT-NMDworkshop on congenital muscular dystrophy (CMD) outcome measures is the 9th CMD workshop, beginning in 1993 with the establishment of a CMD consortium. The workshop brought together 22 clinicians and experts from five countries to advance the implementation of suitable clinical outcome measures and endpoints specific for the CMDs to advance CMD clinical trial readiness. The CMDs are a genetically diverse group of early onset disorders of muscle with dystrophic features in the muscle biopsy. The core genetic groups currently subsumed under the CMDs are the collagen VI related myopathies Ullrich and Bethlem, laminin alpha 2 deficient CMD, the alpha-dystroglycan related CMDs (dystroglycanopathies) and SEPN1 related myopathy (Rigid Spine CMD). Despite the genetic heterogeneity, the clinical problems posed by these conditions are sufficiently interrelated to justify developing an integrated diagnostic, management and therapeutic development approach across CMD forms. Such a unified approach for the CMDs has resulted recently in the launch of an international CMD registry (CMDIR) and a parallel effort to delineate CMD consensus care and diagnostic guidelines, as necessary steps towards the implementation of future CMD clinical trials. The workshop focused on three specific goals: to identify clinically relevant functional classes within the individual CMD subtypes that could be combined for the purpose of clinical outcomes; to review currently available motor scales for their suitability for the functional classes and specific subtypes and to outline CMD common data elements