gms | German Medical Science

Objective: The aim of this study was to compare the sagittal thoracic and lumbar spinal curvatures and pelvic inclination in relaxed standing, slumped sitting and on the canoe in young canoeists.

Material/Methods: A total of 37 young highly-trained canoeists (mean age: 14.91 ± 0.71 years) were recruited. The Spinal Mouse system (Idiag, Fehraltdorf, Switzerland), a hand-held, computer-assisted electromechanical-based device, was used to measure sagittal spinal curvatures and pelvic inclination in relaxed standing, slumped sitting, in the base position (kneeling on one knee in the canoe) and in the catch phase of the stroke. The measurements were made in a randomized order. For each position, the thoracic (T1-2 to T11-12) and lumbar (T12-L1 to the sacrum) spine and the pelvic inclination (difference between the sacral angle and the vertical) were recorded. In the lumbar curve, negative values corresponded to lumbar lordosis (posterior concavity). With respect to the pelvic inclination, a positive value reflected an anterior pelvic tilt while a negative value reflected a posterior pelvic tilt. The classification proposed by Mejia et al. [1] and Tüzün et al. [2] were used to classify the posture in categories for thoracic kyphosis and lumbar lordosis.

Results: The mean thoracic kyphosis in standing, slumped sitting, base position and catch phase in the canoe were 44.42 ± 7.75º, 46.17 ± 9.41º, 38.86 ± 9.42º, and 28.22º ± 10.61, respectively. In the lumbar curve, the mean values were -29.56 ± 8.14º, 21.33 ± 9.94º, -23.69 ± 6.74º, and -13.06 ± 10.84º, respectively. With regard to pelvic inclination, the mean values were 13.89 ± 6.74º, -16.72 ± 8.35º, 14.47 ± 4.08º, and 36.67 ± 6.03º, respectively. The ANOVA revealed significant differences for the main effects of thoracic and lumbar curves and pelvic inclination (p<0.001). Post hoc analysis with Bonferroni correction showed significant differences between all pair-wise comparisons for thoracic kyphosis (p<0.001) (except between standing and slumped sitting), lumbar lordosis (p<0.001), and pelvic inclination (p<0.001) (except between standing and base position). A higher percentage of hyperkyphotic postures in standing (43.2%) than in the canoe was found (29.5% in the base position and 6.8% in the catch phase), while thoracic hypokyphosis increased in the catch phase of the stroke (18.2% in the catch phase and 0% in standing and base position). As regards the lumbar curve, the percentage of hypolordosis postures in the base position was higher than when standing (20.5% vs 9.1%). Lumbar kyphotic postures were only found in the catch phase (13.6%). Hyperlordotic postures were only shown in standing (11.4%).

Conclusion: A higher percentage of hyperkyphotic postures in standing than in the canoe was found, while thoracic hypokyphosis increased in the catch phase of the stroke. The standing thoracic hyperkyphosis in young canoeists may be related to factors other than the posture and movement in the canoe. The canoeists adopted a lumbar flexed posture at the catch phase of the stroke, although this position may not affect the sagittal configuration of lumbar spine in standing. Postural training should be included in the systematic training to improve the thoracic posture in standing.