Changes in lower extremity muscle mass among bedridden patients with post-stroke hemiplegia in the acute post-stroke period

The present study analyzed１６patients who were bedridden for one week immediately after onset of post-stroke hemiplegia. We used DXA（dual energy X-ray absorptiometry）to determine changes in muscle mass in the lower extremities on both paralyzed and non-paralyzed sides. The first measurement was conducted ３ to ５ days after the onset, and the second measurement was conducted ７ days after the first. Muscle mass in the lower extremities was reduced by approximately ６００g （９％） on the paralyzed side with and by ２００g on the non-paralyzed side （３％） in the Brunnstrom stage≤II group （n＝５）. Although the decrease of muscle mass in the Brunnstrom stage≥III group（n＝１１, relatively slight degree of functional motion impairment）was not significant, a decrease of approximately ３００g （decrease rate ： ５％）was observed on the paralyzed side and approximately １００g （decrease rate ： １．５％）was seen on the non-paralyzed side. Hence, muscle mass declined on both sides, and this occurred regardless of degree of paralysis. The findings suggested that conventional range of motion exercises, functional position maintenance, and postural changes are inadequate to prevent disuse muscle atrophy in post-stroke patients ; thus, it is necessary to develop a new rehabilitation program which adopts different exercises such as trunk motion, even for patients in the acute stage after stoke onset.