Diagnosis of Osteosarcopenia – Clinical

Abstract

Over the last two decades several authors have been demonstrating the existence of a wide and complex interaction between muscle and bone, which goes beyond mechanostatic action. Muscle performance as well as osteokines and myokines secreted by both bone and muscle, (respectively) and systemic hormones regulate the growth and performance of both tissues. The dysfunctional interaction between muscle and bone translates into clinical practice in a phenotype of greater risk for falls, physical functional loss and more fractures. In 2009, Binkley et al. call the attention to the individuals who would be the carriers of this phenotype, which would be identified by the association between low bone mass and low muscle mass, then referred to as “sarco-osteopenic or sarco-osteoporotic”. In the following years, the term “osteosarcopenia” arises as a way to encompass the two previous concepts. However, the difficulty in conceptualizing osteosarcopenia increased and, consequently, the variety of diagnostic criteria, which became one of the main challenges for the epidemiological studies and the clinical characterization of these patients. The clinical manifestations of osteosarcopenia include, in part, the same as those observed in subjects with isolated sarcopenia or osteoporosis, however, there are some characteristics that are more specific and that may help the clinician in the identification of these patients. It is important to note that osteosarcopenia is a clinical syndrome due to the physiological and functional deterioration of the musculoskeletal system, which is strongly related to the aging process and differs from isolated osteoporosis and sarcopenia, being associated with worse musculoskeletal outcomes. The other chapters of this book will describe the complexity of this syndrome, which is not limited to the mere association between sarcopenia and osteoporosis, but rather a phenotype of greater clinical vulnerability. In this chapter, we will discuss the most frequent and specific clinical manifestations, based on the compilation of several epidemiological studies.