Relationship between plantar pressure distribution and sagittal spinal curvatures among handball players: A cross-sectional study.

Background: Handball affects the spinal anterior-posterior curvatures and disturbs the foot plantar pressure which provides insights into alterations in an individual's posture. However, little is known about how the mal-alignment affects the distribution of plantar pressure.

Objective: To investigate the relationship between the thoracic kyphosis angle, and plantar pressure distribution among handball players.

Methods: Sixty male handball players were distributed into two groups based on their thoracic kyphosis angles. Group A: 28 handball players with an angle greater than 44^∘ (kyphotic group), and group B: 32 handball players with an angle equal to or less than 44^∘ (normal group). The Formetric III 4D spine and DIERS Pedoscan devices were used to measure the trunk anthropometry and plantar pressure distribution. The Pearson correlation test was used to explore the relationship between the kyphosis angle and plantar pressure distribution.

Results: Group A was significantly taller, had longer trunk length, greater lumbar lordosis angles, and forefoot plantar pressure (FPP), and less rearfoot plantar pressure (RPP) than group B ( $p<0.05$ ). They showed a highly significant positive correlation between the thoracic kyphosis angle and FPP, and a highly significant negative correlation with the RPP ( $r=0.672$ , $-0.650$ , respectively). There was no correlation between the lumbar lordosis angle and FPP or RPP ( $r=0.025$ , $-0.045$ , respectively).

Conclusion: Handball players with greater thoracic kyphosis angle have greater lumbar lordosis angle. Increasing the thoracic kyphosis angle is strongly associated with increased FPP and decreased RPP. While there is no relationship between the lumbar lordosis angle and FPP or RPP.