Valoracion del plano sagital del raquis, el morfotipo sagital integral y la extensibilidad isquiosural en escolares de 3 a 12 años de edad

Abstract

Introduction. The sagittal spinal morphology presents 4 physiological curvatures that increase endurance to axial compression forces and allow adequate postural balance. These curves must remain within normal ranges to achieve a static and dynamic balance, a correct functioning of the muscles and an adequate distribution of the loads, and thus minimize the injury risk. The sagittal spinal misalignments may appear due to an increase (hyperkyphosis, hyperlordosis, and kyphotic-lordotic posture), decrease (flat-back, hypolordosis, and hypokyphosis) or inversion (thoracic lordosis and lumbar kyphosis) of one or both curves or when the normal spine topography is modified (thoracic-lumbar kyphosis, cervical-thoracic kyphosis). Objetives. The main objective of the present study was to categorize the sagittal spinal alignment according to the different morphotypes obtained for each curve in standing, slump sitting, and trunk forward bending positions in schoolchildren. Furthermore, the extensibility of the hamstring muscles was assessed with the sit and reach test and the lumbo-horizontal angle in flexion test. Material and methods. It was a cross-sectional study. Sagittal spinal curvatures and hamstring extensibility were assessed in 422 students from 3 pre-school and elementary schools (age: 8,83±2,27 years, height: 135,91±14,32 cm, weight: 35,81±13,79 kg). The measuring protocol of the “Sagittal Integral Morphotype”, described by Santonja for the complete evaluation of sagittal spinal curvatures (dorsal and lumbar), consists of the sagittal assessment in a relaxed standing position, in a slump sitting position, as well as in trunk forward bending position. The idea of this protocol is to assess the main positions that you can use and adopt in daily and sports activities. Essentially, posture characteristics that can have clinical relevance are quantified using a screening protocol with clinical applicability and are incorporated into a consistent system in which the clinical relevance of the identified posture types is appreciated in terms of their association with the risk of spinal pain and spinal injury. Results. Mean values of thoracic kyphosis were 39.7°+8.8° in standing, 63°+10.5° in maximum trunk flexion and 41.9°+11.3° in seated positions. For the lumbar curve mean values were -32.2°+8.2° in standing, 28.4°+8.9° in maximum trunk flexion and 12°+11.7° in seated positions. In the sagittal standing position assessment, 74.9% and 84.6% of schoolchildren presented a "normal" morphotype for both dorsal and lumbar curves, respectively. After the application of the "Sagittal Integral Morphotype" protocol according to the morphotypes obtained in the three positions assessment (standing, slump sitting, and trunk forward bending), it was observed how the frequency of normal morphotypes for the dorsal and lumbar curve decreased considerably (only 27.2% and 38.9% of children obtained a "normal sagittal integral morphotype" for the thoracic and lumbar curvatures, respectively). In relation with the hamstring extensibility, the results of the present study demonstrate that a low percentage of the students had a normal level of extensibility. Regarding gender, significant differences were observed, where 64.7% of the girls presented normal values and only 25.3% of the boys. Conclusions. These results show how it is necessary to include the slump sitting and trunk forward bending assessment as part of the protocol to define the "integral" sagittal alignment of the spine and establish a correct diagnosis. The use of the diagnostic classification presented in this study will allow early detection of misalignment not identified with the assessment of standing position.