Validity and Reproducibility of the Measurements Obtained Using the Flexicurve Instrument to Evaluate the Angles of Thoracic and Lumbar Curvatures of the Spine in the Sagittal Plane

Abstract

Objective. to verify the validity and reproducibility of using the flexicurve to measure the angles of the thoracic and lumbar curvatures. Method. 47 subjects were evaluated by: (1) palpation and marking of the spinous processes using lead markers, (2) using X-rays in the sagittal plane to measure the Cobb angles, (3) molding the flexicurve to the spine, and (4) drawing the contour of the flexicurve onto graph paper. The angle of curvature was determined with the flexicurve based on a 3rd order polynomial. Results. No differences were found between the Cobb angles and the angles obtained using the flexicurve in thoracic and lumbar curvatures (P > 0.05). Correlations were strong and significant for the thoracic (r = 0.72, P < 0.01) and lumbar (r = 0.60, P < 0.01) curvatures. Excellent and significant correlations were found for both the intraevaluator and interevaluator measurements. Conclusion. The results show that there is no significant difference between the values obtained using the flexicurve and those obtained using the X-ray procedure and that there is a strong correlation between the two methods. This, together with the excellent level of inter- and intraevaluator reproducibility justifies its recommendation for use in clinical practice.

Combined Effects of Postural Education, Therapeutic Massage, Segmental Stretching, and Motor Control Exercise in a 19-Year-Old Male with Chronic Back Pain and Kypholordotic Posture: A Case Report

“…Spine alignment (LLC and TKC) in sagittal plane was measured using a flexible ruler as described by De Oliveira et al (11). The flexible ruler method was shown to be reliable and valid for measuring both LLC and TKC (11).…”

“…The flexible ruler method was shown to be reliable and valid for measuring both LLC and TKC (11). Pain intensity was assessed using a visual analogue scale (VAS; 0 -100 mm) with higher scores indicating higher levels of pain intensity (12).…”

Kyphosis index obtained in X-ray and with flexicurve assessment in children and young people

“…[1][2][3][4][5] Nevertheless, these exams are contraindicated in some population, as for people with cancer, pregnant women 6 and children in the development phase, 7 in addition to being a high cost procedure for underdeveloped and developing countries. 8 Thus, techniques for assessing noninvasive spine have been proposed as they are considered to be of low complexity and low cost. In this context, instruments such as the photogrammetry associated to softwares 9 the arcometer 10 and the flexicurve 8 have driven to new researches on postural assessment in order to promote the use of these low complexity systems.…”

“…8 Thus, techniques for assessing noninvasive spine have been proposed as they are considered to be of low complexity and low cost. In this context, instruments such as the photogrammetry associated to softwares 9 the arcometer 10 and the flexicurve 8 have driven to new researches on postural assessment in order to promote the use of these low complexity systems. The flexicurve already well documented in the literature, consists of a straight ruler, made of plastic-coated metal, which is molded on the back of the individual in order to illustrate the outline of the vertebral column, allowing a quick and cheap assessment of the curvatures of the vertebral column in the clinical environment, and also in study fields or with a big population.…”

“…The flexicurve already well documented in the literature, consists of a straight ruler, made of plastic-coated metal, which is molded on the back of the individual in order to illustrate the outline of the vertebral column, allowing a quick and cheap assessment of the curvatures of the vertebral column in the clinical environment, and also in study fields or with a big population. 8 Therefore, the flexicurve can constitute of a useful tool, especially in monitoring the children and young people's postural treatment, which requires frequent assessments because they are in the development stage 7 and they should not be exposed repeatedly to the deleterious effects of Xray examinations. 6,7 Considering the contour assessment of the vertebral column, the flexicurve can provide angular and linear measurements representing the curvatures.…”