Journal Article

Muscle mass and intramuscular fat of the quadriceps are related to muscle strength in non-ambulatory chronic stroke survivors: A cross-sectional study

Okawa, Naomi, Akazawa, Naoki, Harada, Kazuhiro, Tamura, Kimiyuki, Moriyama, Hideki

2018

Overview

Improving muscle mass and intramuscular fat in the mid-thigh increases the muscle strength of the paretic and non-paretic limbs in ambulatory chronic stroke survivors. There is a remarkable decrease in muscle mass and muscle strength and an increase in intramuscular fat in the quadriceps of both limbs of non-ambulatory compared with ambulatory survivors. Therefore, given that paretic lower extremity function does not recover sufficiently in the chronic phase, it may be helpful to improve muscle mass and intramuscular fat to increase muscle strength in the quadriceps of non-ambulatory chronic stroke survivors. However, these relationships remain unclear. The purpose of this study was to clarify the relationships between muscle strength, muscle mass, and intramuscular fat of the quadriceps in non-ambulatory chronic stroke survivors. Study design: A cross-sectional study. Participants: Fifty non-ambulatory chronic stroke survivors. Main outcome measures: Quadriceps muscle strength was measured using a handheld dynamometer. Transverse ultrasound images were acquired using B-mode ultrasound imaging. Muscle mass and intramuscular fat of the quadriceps were assessed based on muscle thickness and echo intensity, respectively. Data analysis: Stepwise multiple regression analyses were used to identify the factors independently associated with the quadriceps muscle strength of the paretic and non-paretic limbs. To avoid multicollinearity, muscle thickness and echo intensity were entered into separate multiple regression models. Muscle thickness or echo intensity of the paretic or non-paretic limbs and other confounding factors were set as the independent variables. Muscle thickness was positively related and echo intensity was negatively related to the quadriceps muscle strength of the paretic and non-paretic limbs. Muscle mass and intramuscular fat of the quadriceps are related to muscle strength in non-ambulatory chronic stroke survivors. Increasing muscle mass and decreasing intramuscular fat of the quadriceps of both limbs may improve muscle strength.

• Publisher: Public Library of Science,Public Library of Science (PLoS)
• Subject: Adipose Tissue - diagnostic imaging / Adipose Tissue - pathology / Adipose Tissue - physiopathology / Aged / Analysis / Biology and Life Sciences / Chronic Disease / Cross-Sectional Studies / Data analysis / Data processing / Echo surveys / Female / Health aspects / Humans / Image acquisition / Independent variables / Limbs / Male / Medicine and Health Sciences / Multiple regression models / Muscle Strength / Muscle Strength Dynamometer / Muscular strength / Musculoskeletal system / NMR / Nuclear magnetic resonance / Older people / Organ Size / Paresis - diagnostic imaging / Paresis - etiology / Paresis - pathology / Paresis - physiopathology / Physical Sciences / Physical therapists / Physical therapy / Quadriceps muscle / Quadriceps Muscle - diagnostic imaging / Quadriceps Muscle - pathology / Quadriceps Muscle - physiopathology / Regression analysis / Regression models / Research and Analysis Methods / Sarcopenia / Stroke / Stroke - complications / Stroke - diagnostic imaging / Stroke - pathology / Stroke - physiopathology / Stroke patients / Thigh / Ultrasonic imaging / Ultrasonography / Ultrasound / Ultrasound imaging