Effect of Pelvic Tilt on Standing Posture

Abstract

Low back dysfunction is associated in many cases with lumbar lordosis, and tilting the pelvis posteriorly is often recommended for therapeutic purposes. The influence of pelvic tilt on the spinal curves has not been studied. The purpose of this study was to use an objective noninvasive method to determine the effect of the pelvic tilt on the spinal curves in the sagittal plane. Thirty-two healthy subjects and 15 patients with chronic low back dysfunction (CLBD) were studied. Patients with CLBD and healthy subjects were instructed in performing active anterior and posterior pelvic tilt maneuvers, first in the supine and then in the standing position. Comparisons between the Patient Group and the Healthy Group were made for several variables representing the severity of spinal curves, pelvic orientation, hip orientation, and knee orientation. A computerized system, the Iowa Anatomical Position System, was used to obtain coordinates of external body surface landmarks from which pelvic tilt measurements were determined. The results showed that the voluntary pelvic tilt did not alter the thoracic spinal curve. For both the Healthy Group and the Patient Group, the lumbar curve was altered by the pelvic tilt: anterior tilt increased the depth of the lumbar curve and posterior tilt decreased the depth of the lumbar curve. The amount of pelvic tilt was the same whether knees were extended or flexed approximately 10 degrees. Pelvic tilt also tended to influence the orientation of the head and other parts of the body.

Differences in Lower Extremity Anatomical and Postural Characteristics in Males and Females Between Maturation Groups

“…15,32,35,46 Comparison of our findings with previous literature is quite limited, as we were unable to find any other studies comparing pelvic angle during maturation. While comparison of our mean values for mature adolescents (MatGrp 3 , 10.8°) appear to be consistent with angles observed in adults (range, 9°-12°), 3,18,24,25,43,54,71 only 1 of these studies compared values in males and females. 54 In a cohort of 50 females and 50 males (mean SD age,23.3 3.6 years;range,(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34) Nguyen and Shultz 54 reported greater mean SD pelvic angles in females (12.0° 4.6°) compared to males (8.7° 3.8°).…”

“…While comparison of our mean values for mature adolescents (MatGrp 3 , 10.8°) appear to be consistent with angles observed in adults (range, 9°-12°), 3,18,24,25,43,54,71 only 1 of these studies compared values in males and females. 54 In a cohort of 50 females and 50 males (mean SD age,23.3 3.6 years;range,(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31)(32)(33)(34) Nguyen and Shultz 54 reported greater mean SD pelvic angles in females (12.0° 4.6°) compared to males (8.7° 3.8°). While more work is needed in this area, available evidence to date suggests that the sex differences observed in adult pelvic angles are likely not due to structural development, but rather may represent chronic functional adaptations that occur secondary to other factors.…”

Sex Differences in Clinical Measures of Lower Extremity Alignment

“…2,14,19,20,42,73 Of the few studies reporting mean values based on both males and females, sex differences were not examined. 2,20,73 We observed a significant difference between sexes, with females having 3° to 4° greater anterior pelvic angle than males.…”

“…Muscular tightness and shortening of the erector spinae and hip flexors, and elongation and weakening of the abdominals and gluteals have been suggested to result in greater anterior pelvic angle. 27,37 The relationship between pelvic angle and these muscles may potentially explain the sex difference in pelvic angle, as females have been observed to have decreased strength in hip abduction, 7,10,40,53 extension, 10 and external rotation, 10,40 and increased lumbar lordosis 14,16,19,20,37,42 compared to males.…”

Influência da porção extensora do músculo glúteo máximo sobre a inclinação da pelve antes e depois da realização de um protocolo de fadiga

“…The lumbar spine demonstrates several factors which contribute to its stabilization, such as the passive elastic forces of the soft tissues that cross the intervertebral joints and the muscles which are adjacent to these forces, and the ones which are responsible for the stabilization of proximal bone segments 1 . Thus, some observational studies have been performed in relation to lumbar spine movement and the consequent pelvic movement [2][3][4] . These studies associated the anterior and posterior pelvic tilt, respectively, to proportional increases or reductions on the lumbar curvature.…”