Bone Quality in Patients with a Congenital Myopathy: A Scoping Review

Background: Congenital myopathies are rare neuromuscular disorders presenting with a wide spectrum of clinical features, including long bone fractures (LBFs) that negatively influence functional prognosis, quality of life and survival. Systematic research on bone quality in these patients is lacking. Objective: This scoping review aims to summarize all evidence on bone quality and to deduce recommendations for bone quality management in congenital myopathies. Methods: Five electronic databases (Pubmed, Embase, Cochrane, Web of Science, CINAHL) were searched. All studies on bone quality in congenital myopathies were included. Decreased bone quality was defined as low bone mineral density and/or (fragility) LBFs. Study selection and data extraction were performed by three independent reviewers. Results: We included 244 single cases (mean: 4.1 +/- 7.6 years; median: 0 years) diagnosed with a congenital myopathy from 35 articles. Bone quality was decreased in 93 patients (37%) (mean: 2.6 +/- 6.8 years; median: 0 years). Low bone mineral density was reported in 11 patients (4.5%) (mean: 10.9 +/- 9.7; median: 11 years). Congenital LBFs were reported in 64 patients (26%). (Fragility) LBFs later at life were described in 24 patients (9.8%) (mean: 14.9 +/- 11.0; median: 14 years). Four cases (1.6%) were reported to receive vitamin D and/or calcium supplementation or diphosphonate administration. Conclusion: LBFs are thus frequently reported in congenital myopathies. We therefore recommend optimal bone quality management through bone mineral density assessment, vitamin D and calcium suppletion, and referral to internal medicine or pediatrics for consideration of additional therapies in order to prevent complications of low bone mineral density.