4. Relevance to physical therapy

7.2 5.1, and 25.9 7.6, respectively (Table 2). The range of pelvic motion in the stand-unable group was significantly smaller in comparison to the stand-able and control groups (Table 2).

Table 2. The mean and standard deviation of the pelvic in the stand-able, stand-unable, and control groups [45].

Stand-able group (n = 18)

Maximum pelvic Mean SD 1.2 2.8 12.4 6.1a,b 1.6 5.0 anteversion angle (º) Range (max–min 5 to 4 5 to 22 10 to 13 Maximum pelvic Mean SD 18.5 5.6<sup>b</sup> 19.6 4.6<sup>b</sup> 27.6 8.1 retroversion angle (º) Range (max–min) 30 to 10 27 to 10 46 to 10 Range of pelvic motion Mean SD 19.7 5.1<sup>b</sup> 7.2 5.1b 25.9 7.6 (º) Range (max–min) 28 – 10 15 – 0 49 – 9

Stand-unable group

Control group (n = 50)

(n = 14)

The hypotheses that the maximum pelvic anteversion angle and the range of pelvic motion in the stand-able group would be significantly larger in comparison to the stand-unable group were confirmed. It is noteworthy that there was a cut-off value maximum pelvic anteversion angle that could divide stroke patients into the stand-able and stand-unable groups. The data suggest that, in order for stroke patients to perform the sit-to-stand movement, the maximum

To smoothly execute the sit-to-stand movement, the pelvis is anteverted to flex the hip joint and the trunk to perform the hip extension moment, reduce the knee extension moment, and project the center of gravity into the base of support [38–43]. The sitting position stability of stroke patients has been shown to be worse than that in age-matched healthy subjects [5, 11, 12]. It has been shown that stroke patients cannot sufficiently flex the hip joint when it is necessary to activate the trunk extensor muscles during sitting [33]. Stroke patients usually sit with kyphosis and pelvic retroversion to avoid falling backward due to insufficient function of the abdominal muscles. Thus, when performing the sit-to-stand movement, stroke patients may need to lean the trunk further forward to shift the center of gravity into the base of support using their feet due to the increased kyphosis and pelvic retroversion. Lecours et al. observed that, when performing the sit-to-stand movement, the trunk angle during forward leaning in stroke patients was larger than that in healthy subjects [35]. Hesse et al. reported that the average center of gravity projection in the base of support in stroke patients was 3 cm behind that of healthy subjects during the seat off phase in the sit-to-stand movement [49]. In addition, when the trunk is flexed, the hip extension moment becomes insufficient due to the lack of pelvic anteversion; thus, stroke patients may depend primarily on the knee extension

Some studies have reported a high correlation between pelvic inclination in the sitting position and the degree of lumbar lordosis [5] and a strong relationship between the sacral angle of inclination and the degree of lumbar lordosis [46, 47]. Hence, pelvic inclination (anteversion and retroversion) reflects lumbar movement (lordosis and kyphosis). The range of pelvic

pelvic anteversion angle should be greater than 5.

<sup>a</sup> Significant difference from the stand-able group. <sup>b</sup> Significant difference from control group.

50 Clinical Physical Therapy

movement to stand up.

This session demonstrated that the pelvic range of motion was affected by aging, particularly in the anteversion angle, and that the maximum pelvic anteversion angle and the range of pelvic motion in the stand-able group were significantly larger than those in the stand-unable group. Notably, if these patients are to be able to perform the sit-to-stand movement, it is important that they acquire a pelvic anteversion angle of greater than 5.

The mobility of the lumbar spine, which is associated with the strength and coordination of the trunk and the lower limbs, should be considered as the background of these results. The physical therapy program described below would help as an initial step for improving the physical function of elderly individuals and stroke patients—especially with regard to improving their sit-to-stand movement.

For elderly individuals: (1) pelvic anteversion and retroversion—the patient should maintain a seated position with their feet contacting the floor in a parallel position and move slowly, alternating the pelvis from maximum anteversion to maximum retroversion. They should maintain the same shoulder anteroposterior position throughout the pelvic inclination movements in order to avoid anteroposterior movement of the trunk. (2) Leaning the trunk forward with pelvic anteversion—the patient should lean their trunk forward maintaining pelvic anteversion in a seated position with their feet contacting to the floor. This movement should be performed slowly and repeated. It is important to perceive the increasing load to the lower limb during the leaning of the trunk.

For stroke patients: as soon as the stroke patient has obtained an independent sitting position, the treatment should focus on the mobility of the trunk and weight transfer to the lower limbs, using the same methods as for elderly individuals.
