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A cumulative analogue joint involvement scale (CAJIS) for fibrodysplasia ossificans progressiva (FOP)
Frederick S Kaplan1, Mona Al Mukaddam2, Robert J Pignolo3
1Department of Orthopaedic Surgery, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States; Department of Medicine, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States; The Center for Research in FOP and Related Disorders, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, United States.
Background:
Fibrodysplasia ossificans progressiva (FOP) is a catastrophic genetic disorder of progressive heterotopic ossification (HO). Assessment of functional mobility in FOP will be essential to support clinical trials of investigational agents.
Results:
Of necessity, we developed a simple, rapidly-administered, cumulative analogue joint involvement scale (CAJIS) for FOP based on assessments in 144 individuals worldwide with classic FOP.
Conclusions:
CAJIS scores correlated with patient age, activities of daily living, and ambulatory function with excellent inter-rater variability. We show here that the CAJIS score provides an accurate and reproducible snapshot of total body and regional mobility burden in FOP.
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