Neuromuscular Diseases and Bone

Abstract

Neuromuscular diseases (NMDs) are inherited or acquired conditions affecting skeletal muscles, motor nerves, or neuromuscular junctions. Most of them are characterized by a progressive damage of muscle fibers with reduced muscle strength, disability, and poor health-related quality of life of affected patients. In this scenario, skeletal health is usually compromised as a consequence of modified bone–muscle cross-talk including biomechanical and bio-humoral issues, resulting in increased risk of bone fragility and fractures. In addition, NMD patients frequently face nutritional issues, including malnutrition due to feeding disorders and swallowing problems that might affect bone health. Moreover, in these patients, low levels of physical activity or immobility are common and might lead to overweight or obesity that can also interfere with bone strength features. Also, vitamin D deficiency could play a critical role both in the pathogenesis and in the clinical scenario of many NMDs, suggesting that its correction could be useful in maintaining or enhancing bone health, especially in the early phases of NMDs. Last but not least, specific disease-modifying drugs, available for some NMDs, are frequently burdened with adverse effects on bone tissue. For example, glucocorticoid therapy, standard of care for many muscular dystrophies, prolongs long-term survival in treated patients; nevertheless, high dose and/or chronic use of these drugs are a common cause of secondary osteoporosis. This review addresses the current state of knowledge about the factors that play a role in determining bone alterations reported in NMDs, how these factors can modify the biological pathways underlying bone health, and which are the available interventions to manage bone involvement in patients affected by NMDs. Considering the complexity of care of these patients, an interdisciplinary and multimodal management strategy based on both pharmacological and non-pharmacological interventions is recommended, particularly targeting musculoskeletal issues that are closely related to functional independence as well as social implications.

Effects of Teleassistance on the Quality of Life of People With Rare Neuromuscular Diseases According to Their Degree of Disability

“…Despite their complexity, they tend to share a number of characteristics, such as their chronicity and progressiveness, which may also be accompanied by dependency or disability, highlighting their chronicity. These diseases usually cause people who suffer them to require specialized, long-term care ( ASEM, 2008 ; Amayra et al, 2014 ; Dowling et al, 2018 ; Iolascon et al, 2019 ).…”

Skeletal Effects of Bone-Targeted TGFbeta Inhibition in a Mouse Model of Duchenne Muscular Dystrophy

“…Apart from the primary muscle defect, the bone disease is a frequent clinical problem in DMD [8,9]. Boys with DMD have multiple risk factors for developing secondary Life 2021, 11, 791 2 of 10 osteoporosis, including muscle weakness, reduced mobility as well as glucocorticoid therapy [10][11][12].…”

“…Boys with DMD have multiple risk factors for developing secondary Life 2021, 11, 791 2 of 10 osteoporosis, including muscle weakness, reduced mobility as well as glucocorticoid therapy [10][11][12]. Osteoporosis in boys with DMD leads to fractures of the extremities and vertebral bodies [8,9]. Overall, 30% of boys with DMD have extremity fractures and more than half will eventually have a vertebral fracture [11,12].…”

“…Fractures in boys with DMD can lead to premature loss of ambulation and even death [ 13 , 14 ]. Thus, approaches to prevent and treat osteoporosis are an important component of DMD care [ 8 , 9 ].…”

Exercise-Related Oxidative Stress as Mechanism to Fight Physical Dysfunction in Neuromuscular Disorders

“…Neuromuscular disease (NMD) is a quite broad nosographic term, which refers to different disorders either affecting the spinal cord anterior motoneuron horn cell, the peripheral nervous system, or neuromuscular junction and skeletal muscle (Iolascon et al, 2019), i.e., the components of what is termed the motor unit, an anatomic-physiological entity fundamental to realize the voluntary movement. In the case of conditions affecting the peripheral nervous system, also the sensitive pathways are involved in the pathological process, accordingly enriching clinical appearance with additional specific features.…”