Effects of age-related changes in trunk and lower limb range of motion on gait.

BACKGROUND: The ability to walk is crucial for maintaining independence and a high quality of life among older adults. Although gait characteristics have been extensively studied in older adults, most studies have investigated muscle activity in the joints of the trunk or the lower limbs without assessing their interactions. Thus, the causes of altered trunk and lower limb movement patterns in older adults remain to explore. Therefore, this study compared the joint kinematic parameters of both trunk and lower limbs between young and older adults to identify kinematic factors associated with changes in gait among older adults. METHODS: In total, 64 older (32 males, aged 68.34 ± 7.38 years; 32 females, aged 67.16 ± 6.66 years) and 64 young (32 males, aged 19.44 ± 0.84 years; 32 females, aged 19.69 ± 0.86 years) healthy adults participated in this study. The range of motion (ROM) of the thorax, pelvis, and trunk in the horizontal plane and of the hip, knee, and ankle joints of the lower limbs in the sagittal plane were measured using a motion capture system with wearable sensors. Two-way analysis of variance assessed differences in ROM by group, sex, and spatio-temporal gait parameters; Pearson correlation analysis assessed the correlation of the trunk and lower limbs. RESULTS: Step length, gait speed, and stride length were greater in young adults (p < 0.001) than in older adults, but older women displayed the fastest gait speed (p < 0.05). ROM values for the pelvis, thorax, trunk, knee joint, and ankle joint of young adults were greater (p < 0.05) than those in older adults. However, hip ROM in older adults was significantly greater than that in young adults (p < 0.05). CONCLUSION: With increasing age, ROM of the lower limbs, especially the ankle joint, decreased significantly, resulting in a significant decrease in gait speed. As ROM of the pelvis decreased, stride length decreased significantly in older adults, who compensate through thoracic rotation. Thus, older adults should enhance muscle strength and increase ROM to improve gait patterns.

Effects of a postural cueing for head and neck posture on lumbar lordosis angles in healthy young and older adults: a preliminary study.

BACKGROUND: Postural rehabilitation plays an important role in the treatment of non-specific low back pain. Although pelvic inclination has been widely used to improve lumbar lordosis, the effect of cervical anterior inclination on lumbar lordosis in young and older adults in sitting and standing posture is still unclear. This preliminary study was designed to examine the influence of changing the cervical anterior angle on the lumbar lordosis angle, through alterations of the head position under the natural sitting and standing conditions, aiming to provide a basis for establishing a new postural rehabilitation strategy. METHODS: Thirty-six young (24.0 ± 2.2 years, 14 females and 22 males) and 38 older (68.4 ± 5.9 years, 36 females and 2 males) healthy adults participated in this study. The four spinal regional angles-cervical anterior angle, thoracic kyphosis angle, lumbar lordosis angle, and pelvic forward inclination angle, were measured in standing and relaxed sitting postures to determine the effects of a postural cueing for the head and neck posture, "inclining head backward and performing chin tuck," on lumbar lordosis angle. RESULTS: In the standing posture, the pelvic forward inclination angle in the older adult group was significantly smaller (P < 0.001, by ANOVA) than that in the young adult group and increased significantly (P < 0.001) in response to the postural cueing. In addition, the thoracic kyphosis angle in the standing (P = 0.001) and sitting (P = 0.003) positions was significantly reduced in response to the postural cueing. However, the lumbar lordosis angle in response to the postural cueing increased significantly in both the standing position (P < 0.001) and sitting position (P < 0.001). CONCLUSION: The results suggest that increasing the cervical anterior angle can increase the lumbar lordosis angle, and the cervical anterior inclination can be used as an alternative to pelvic forward inclination to improve the lumbar lordosis angle. Furthermore, the change in head and neck posture can reduce the thoracic kyphosis angle, making it possible to establish a new noninvasive body posture rehabilitation strategy.