Gender differences in degenerative lumbar scoliosis spine flexibilities

Objectives: The incidence of adolescent idiopathic scoliosis is higher in girls, but spine deformities are more severe in boys. We aimed to identify gender differences of mechanical factors involved in adult degenerative scoliosis (DS). Methods: 20 male (60.35 +/- 6.77 years) and 19 female (58.89 +/- 9.15 years) specimens of cadaveric lumbar spines were divided into 3 groups comprised of a Cobb angle >10 degrees (DS), a Cobb angle <10 degrees but >3 degrees (pre-degenerative scoliosis (PS)) and intervertebral disc angles <3 degrees in which the Cobb angle could not be measured (non-degenerative scoliosis (NS)), respectively. Spine data were collected for flexion/extension (FE), lateral bending (LB), axial torsion (AT), range of motion (ROM), neutral zone (NZ) and the neutral zone ratio (NZR). Results: There was no significant difference regarding the severity of DS between male and female specimens. Only in males were ROMAT (P=0.001), NZ(AT) (P<0.001), NZ(FE) (P=0.045), NZ(LB) (P=0.002) as well as NZR(AT) (P<0.001) and NZR(LB) (P=0.001) values significantly lower in right compared to left scoliosis. With the exception of ROMAT in DS specimens, ROMAT, ROMFE and ROMLB values were significantly higher in females than those in males for the DS, PS and NS specimens. NZ(AT), NZ(FE) and NZ, values were significantly higher in PS and NS female specimens. NZR(AT) was significantly lower in female DS specimens (P=0.031) and significantly higher in female PS specimens (P=0.031) compared to that in male specimens. Conclusions: In lumbar scoliosis specimens, the rigidness of spines was higher in males than in females and more pronounced in right than in left scoliosis, but only in males.

Automated summary

The study found no significant differences between male and female specimens with adult degenerative scoliosis. The rigidity of spines was higher in males than in females, especially in right scoliosis.