Natural aging course of paraspinal muscle and back extensor strength in community-dwelling older adults (sarcopenia of spine, SarcoSpine): a prospective cohort study protocol.

Introduction: Sarcopenia in the lumbar paraspinal muscles is receiving renewed attention as a cause of spinal degeneration. However, there are few studies on the precise concept and diagnostic criteria for spinal sarcopenia. Here, we develop the concept of spinal sarcopenia in community-dwelling older adults. In addition, we aim to observe the natural ageing process of paraspinal and back muscle strength and investigate the association between conventional sarcopenic indices and spinal sarcopenia.

Methods And Analysis: This is a prospective observational cohort study with 120 healthy community-dwelling older adults over 4 years. All subjects will be recruited in no sarcopenia, possible sarcopenia or sarcopenia groups. The primary outcomes of this study are isokinetic back muscle strength and lumbar paraspinal muscle quantity and quality evaluated using lumbar spine MRI. Conventional sarcopenic indices and spine specific outcomes such as spinal sagittal balance, back performance scale and Sorenson test will also be assessed.

Ethics And Dissemination: Before screening, all participants will be provided with oral and written information. Ethical approval has already been obtained from all participating hospitals. The study results will be disseminated in peer-reviewed publications and conference presentations.

Trial Registration Number: NCT03962530.