Sexual Receptivity Signal of Lordosis Posture and Intra-Sexual Competition in Women

Previous research has shown that women may use self-enhancement strategies to compete with one other. Lumbar curvature in women is considered to enhance a woman′s attractiveness, potentially due to its role in bipedal fetal load and sexual receptiveness. The current study investigated the role of lumbar curvature on women’s perceptions of sexual receptiveness as well as its role in women’s intrasexual competitiveness. Study 1 (N = 138) tested and confirmed that women’s intrasexual competition influences their perception of sexual receptivity of women as a function of lordosis posture depicted in a standing posture. Study 2 (N = 69) replicated these results and extended them to other postures, namely, the quadruped and supine positions. Study 3 (N = 106), using a two-alternative forced-choice task, revealed that other women perceive relatively larger arched-back postures as more threatening to their relationship and frequently as being more attractive. Collectively, this work suggests that women consider a lordotic posture in other women as a signal of sexual receptivity and perceive it as a threat to their relationship. This research provides robust support for the sexually receptivity hypothesis of lumbar curvature, questioning the alternative morphological vertebral wedging hypothesis.

Effects of a Verbal Intervention 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-eight older (68.4 ± 5.9 years old) and 36 young (24.0 ± 2.2 years old) healthy adults participated in this study. The four spinal regional angles - cervical anterior angle, thoracic kyphosis angle, lumbar lordosis angle, and pelvic foreword inclination angle were measured in standing and relaxed sitting postures to determine the effects of a postural cueing, “inclining head backward and performing chin tuck”, for the head and neck posture on lumbar lordosis angle.Results In the standing posture, the pelvic foreword inclination angle in the older group was significantly smaller (P <0.001) than that in the young group, and increased significantly (P <0.001) post the postural cueing. In addition, the thoracic kyphosis angle in the standing (P = 0.001) and sitting (P = 0.003) positions was significantly reduced post the postural cueing. However, the lumbar lordosis angle post 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 indeed increase the lumbar lordosis angle, and the cervical anterior inclination can be used as an alternative to pelvic foreward inclination to improve the lumbar lordosis angle. Furthermore, the change of head and neck posture can reduce the thoracic kyphosis angle, making it possible to establish a new non-invasive body posture rehabilitation strategy.(approval number TJUS2019032)

Evaluation of Hindlimb Deformity and Posture in Dogs with Grade 2 Medial Patellar Luxation during Awake Computed Tomography Imaging while Standing

Objective The aim of this study was to determine the degree of bone deformities and hindlimb postural abnormalities in a standing position in awake Toy poodles with and without grade 2 medial patellar luxation (MPL) using high speed 320-row computed tomography (CT). Methods The limbs with grade 2 MPL (MPL-G2 group) and without any orthopaedic disorders (control group) were imaged in a standing position, without sedation or anaesthesia, using CT. In MPL-G2 group, images were obtained when the patella was luxated (G2-L group) and reduced (non-luxation, G2-NL group). Bone morphologies of the femur and tibia were quantified three-dimensionally. Hindlimb standing posture was evaluated by measuring femoral rotation and abduction angles, tibial rotation angle, metatarsal rotation angle, foot rotation angle, angle between the femoral anatomical axis and the mechanical axis of hindlimb and stifle joint line convergence angle. Results There were no significant differences in bone morphologic parameters between the MPL-G2 group (5 limbs) and the control group (6 limbs). In the G2-NL group, there were no significant hindlimb postural abnormalities. In contrast, in the G2-L group, significant hindlimb postural abnormalities including external rotation of femur, internal rotation of tibia and foot, external rotation of tarsal joint, large stifle joint convergence angle, genu varum and toe-in standing were observed. Conclusion Dogs with grade 2 MPL have no bone deformities but show abnormal standing posture when the patella is luxated.

Analysis of Light Grip Influence on Standing Posture

Upright posture control and gait are essential for achieving autonomous daily living activities. Postural control of upright posture relies, among others, on the integration of various sensory information. In this context, light touch (LT) and light grip (LG) of a stationary object provide an additional haptic sensory input that helps to reduce postural sway. When LG was studied through the grasp of a cane, the sensory role of this assistive tool was often limited to a mediation interface. Its role was restricted to transmit the interaction forces between its tip and the ground to the hand. While most studies involve participants standing in an unstable way, such as the tandem stance, in this paper we study LG from a different perspective. We attached a handle of a cane firmly to a stationary support. Thus, we can focus on the role of the hand receptors in the LG mechanism. LG condition was ensured through the tactile information gathered by FSR sensors placed on the handle surface. Moreover, participants involved in our study stood in a usual way. The study involved twelve participants in an experiment composed of two conditions: standing relaxed while lightly gripping an equipped handle attached to the ground, and standing in the same way without gripping the handle. Spatial and frequency analyses confirmed the results reported in the literature with other approaches.

Effects of Galvanic Vestibular Stimulation on Visual Verticality and Standing Posture Differ Based on the Polarity of the Stimulation and Hemispheric Lesion Side in Patients With Stroke

Introduction: There is growing evidence supporting the relationship of vertical misperception and poor balance control with asymmetrical standing posture in patients with stroke. Although the vestibular system has been shown to be responsible for vertical misperception and balance disorders, the effect of galvanic vestibular stimulation (GVS) on both vertical misperception and postural asymmetry after stroke remains elusive. The aim of this study was to investigate the effects of GVS on visual verticality and postural asymmetry after stroke and to clarify whether the effects differ depending on the polarity of the stimulation and hemispheric lesion side.Methods: We measured the subjective visual vertical (SVV) and body weight distribution on each foot in an upright stance in 24 patients with a hemispheric stroke (10 with a left hemisphere lesion and 14 with a right hemisphere lesion) and nine age-matched healthy controls. During the measurements, bipolar GVS (1.5 mA) was applied over the bilateral mastoid processes in three stimulation conditions: contralesional-anodal and ipsilesional-cathodal vestibular stimulation, ipsilesional-anodal and contralesional-cathodal vestibular stimulation, and no stimulation. To examine whether GVS modulates visual verticality and standing posture, SVV and weight-bearing in the three conditions were analyzed.Results: During no stimulation, the SVV deviated to the contralesional side in patients with a right hemisphere lesion, while more weight-bearing was observed on the ipsilesional limb than on the contralesional limb in both patient groups than in the controls. The SVV was modulated by reversing the polarity of GVS in all the groups when the cathodal stimulus side was either ipsilateral or contralateral to the lesion while the ipsilesional-cathodal vestibular stimulation reduced weight-bearing asymmetry in only the patients with a right hemisphere lesion.Conclusions: These findings demonstrate that the effects of GVS on the SVV and standing posture differ depending on the polarity of GVS and the hemispheric lesion side. Patients with a right hemisphere lesion have difficulty maintaining their preferred standing posture under visual verticality modulation evoked by GVS. The application of GVS may clarify whether the vestibular system has neural redundancy after stroke to suppress any effects of the stimulation, including modulation of the visual verticality, on balance.

Sling suspension therapy is an effective treatment method of juvenile spinal osteochondrosis in adolescent girls

BACKGROUND: Juvenile spinal osteochondrosis (JSO) affects vertebral endplates and may cause intervertebral discs alterations. The condition is typically related to pain, and weakness and shortening of trunk muscles. Sling suspension therapy (SST) has been shown to reduce lumbar pain effectively. It is, however, unclear whether SST is superior to other treatment methods in reducing pain, correcting posture, and activating trunk stabilizers in JSO. OBJECTIVE: In this study, we intended to compare the effectiveness of two different exercise modalities; Sling Suspension Therapy and Gym Ball Exercise in the treatment of JSO in adolescent girls. METHODS: A randomised controlled single centre clinical trial was carried out in an inpatient rehabilitation unit at a sanatorium. Forty adolescent girls (age 16.3 ± 0.47 yrs.), who were diagnosed with JSO (according to ICD-10 Version: 2016 – M 42.0) were randomly assigned into two groups: Group 1 – Sling suspension therapy (SST), Group 2 – Gym ball exercises (GBE). Both groups received interventions for 3 weeks, 15 sessions, and 30 minutes a day for 5 consecutive days a week. Back pain, endurance of trunk muscles and standing posture were evaluated pre- and post-interventions. RESULTS: Both groups demonstrated significant improvement in all measured outcomes. SST was more effective in reducing pain (p< 0.05), increasing the endurance of trunk muscles (p< 0.05) and improving the standing posture (p< 0.05) compared to GBE (p< 0.05). CONCLUSIONS: Sling suspension therapy is more effective compared with Gym ball exercises in the treatment of juvenile spinal osteochondrosis in adolescent girls in terms of back pain, posture and endurance of trunk muscles.