Comparison of the mass and amount of intramuscular non-contractile tissue of the trunk and lower extremity muscles between patients with Parkinson's disease and community-dwelling older adults.

OBJECTIVE: This study compared the masses and amounts of intramuscular non-contractile tissue of the trunk and lower extremity muscles, sagittal spinal alignment, and mobility and balance ability between patients with Parkinson's disease (PD) and older adults. METHODS: This study included 26 older adults (control [CTR] group) and eight patients with PD (PD group). Muscle thicknesses and echo intensities of the trunk and lower extremity muscles were measured using an ultrasound imaging device. Sagittal spinal alignments in the standing and prone positions were assessed using a Spinal Mouse. Mobility capacity was assessed based on the measurements of usual and maximal walking speeds, timed up-and-go (TUG) time, and five-chair-stand time, while balance ability was assessed based on the measurement of one-legged stance (OLS) time. RESULTS: Our results showed significantly lower gluteus maximus and tibialis anterior muscle thicknesses, higher thickness of the short head of the biceps femoris muscle, and higher echo intensity of the gluteus maximus muscle in the PD group than in the CTR group. Lumbar lordosis angle in the standing position, usual and maximal walking speeds, and OLS time were significantly lower, while the TUG and five-chair-stand times were significantly higher in the PD group than in the CTR group. The other factors did not differ significantly between groups. CONCLUSIONS: Our results revealed lower masses of the gluteus maximus and tibialis anterior muscles, higher mass of the short head of the biceps femoris muscle, and higher amounts of intramuscular non-contractile tissue of the gluteus maximus muscle in patients with PD.

Association of mobility capacity with the masses and amounts of intramuscular non-contractile tissue of the trunk and lower extremity muscles in community-dwelling older adults.

We examined the association of mobility capacity with muscle thicknesses and echo intensities of the trunk and lower extremity muscles measured using an ultrasound imaging device in community-dwelling older adults. The participants were 57 community-dwelling older adults. Mobility capacity was assessed based on the measurement of usual and maximal walking speeds and timed up-and-go (TUG) time. Muscle thickness and echo intensity of the trunk and lower extremity muscles were measured using an ultrasound imaging device. Finally, sagittal spinal alignment was assessed based on the measurement of thoracic kyphosis, lumbar lordosis, and sacral anterior inclination angles in the standing position using a Spinal Mouse. Stepwise regression analysis showed that the tibialis anterior muscle thickness, tibialis posterior muscle echo intensity, and body weight were significant and independent factors of usual walking speed, with a coefficient of determination (R2) of 0.25. The thicknesses of the thoracic erector spinae and obliquus externus abdominis muscles were significant and independent factors of maximal walking speed (R2 = 0.26). Moreover, only age was a significant and independent factor for TUG time (R2 = 0.10). The results of this study suggested associations 1) between slow usual walking speed and low tibialis anterior muscle thicknesses and high echo intensity of the tibialis posterior muscle and 2) between slow maximal walking speed and low thoracic erector spinae and obliquus externus abdominis thicknesses in community-dwelling older adults.