Frederick S Kaplan1, Mona Al Mukaddam2, Robert J Pignolo3. 1. Department 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. Electronic address: frederick.kaplan@uphs.upenn.edu. 2. 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; Clinical Medicine, Division of Endocrinology, Diabetes and Metabolism, Center for Research in FOP & Related Disorders, Penn Medicine University City, 3737 Market Street, 3rd floor, United States. Electronic address: Mona.AlMukaddam@uphs.upenn.edu. 3. Department of Medicine, Mayo Clinic School of Medicine, Mayo Clinic, Rochester, MN, United States. Electronic address: pignolo.robert@mayo.edu.
Abstract
BACKGROUND: Flare-ups of the hips are among the most feared and disabling complications of fibrodysplasia ossificans progressiva (FOP) and are poorly understood. In order to better understand the nature of hip flare-ups in FOP, we evaluated 25 consecutive individuals with classic FOP (14 males, 11 females; 3-56years old, median age, 17years old) who presented with acute unilateral hip pain. RESULTS: All 25 individuals were suspected of having a flare-up of the hip based on clinical history and a favorable response to a four day course of high-dose oral prednisone. Ten individuals (40%) experienced rebound symptoms of pain and/or stiffness within seven days after discontinuation of prednisone and all ten subsequently developed heterotopic ossification (HO) or decreased mobility of the affected hip. None of the 14 individuals who experienced sustained relief of symptoms following a course of oral prednisone experienced HO or decreased mobility. Incidental radiographic findings at the time of presentation were multifactoral and included osteochondromas of the proximal femur (18/25; 72%), degenerative arthritis (17/25; 68%), developmental hip dysplasia (15/25; 60%), previously existing heterotopic ossification (12/25; 48%), intra-articular synovial osteochondromatosis (8/25; 32%) or traumatic fractures through pre-existing heterotopic bone (1/25; 4%). CONCLUSIONS: Developmental joint pathology may confound clinical evaluation of hip pain in FOP. The most useful modality for suspecting an ossification-prone flare-up of the hip was lack of sustained response to a brief course of oral prednisone. Evaluation of soft tissue edema by ultrasound or magnetic resonance imaging showed promise in identifying ossification-prone flare-ups and warrants further analysis in prospective studies.
BACKGROUND: Flare-ups of the hips are among the most feared and disabling complications of fibrodysplasia ossificans progressiva (FOP) and are poorly understood. In order to better understand the nature of hip flare-ups in FOP, we evaluated 25 consecutive individuals with classic FOP (14 males, 11 females; 3-56years old, median age, 17years old) who presented with acute unilateral hip pain. RESULTS: All 25 individuals were suspected of having a flare-up of the hip based on clinical history and a favorable response to a four day course of high-dose oral prednisone. Ten individuals (40%) experienced rebound symptoms of pain and/or stiffness within seven days after discontinuation of prednisone and all ten subsequently developed heterotopic ossification (HO) or decreased mobility of the affected hip. None of the 14 individuals who experienced sustained relief of symptoms following a course of oral prednisone experienced HO or decreased mobility. Incidental radiographic findings at the time of presentation were multifactoral and included osteochondromas of the proximal femur (18/25; 72%), degenerative arthritis (17/25; 68%), developmental hip dysplasia (15/25; 60%), previously existing heterotopic ossification (12/25; 48%), intra-articular synovial osteochondromatosis (8/25; 32%) or traumatic fractures through pre-existing heterotopic bone (1/25; 4%). CONCLUSIONS: Developmental joint pathology may confound clinical evaluation of hip pain in FOP. The most useful modality for suspecting an ossification-prone flare-up of the hip was lack of sustained response to a brief course of oral prednisone. Evaluation of soft tissue edema by ultrasound or magnetic resonance imaging showed promise in identifying ossification-prone flare-ups and warrants further analysis in prospective studies.
Keywords:
ACVR1; Bone morphogenetic protein (BMP); Bone morphogenetic protein signaling; Fibrodysplasia ossificans progressiva (FOP); Heterotopic ossification
Authors: Anthony Tucker-Bartley; Jordan Lemme; Andrea Gomez-Morad; Nehal Shah; Miranda Veliu; Frank Birklein; Claudia Storz; Seward Rutkove; David Kronn; Alison M Boyce; Eduard Kraft; Jaymin Upadhyay Journal: Neurosci Biobehav Rev Date: 2021-02-10 Impact factor: 9.052
Authors: Robert J Pignolo; Geneviève Baujat; Matthew A Brown; Carmen De Cunto; Maja Di Rocco; Edward C Hsiao; Richard Keen; Mona Al Mukaddam; Kim-Hanh Le Quan Sang; Amy Wilson; Barbara White; Donna R Grogan; Frederick S Kaplan Journal: Orphanet J Rare Dis Date: 2019-05-03 Impact factor: 4.123