BackgroundWater pressure and muscle contraction may influence bone mineral density (BMD) in a positive way. However, divers experience weightlessness, which has a negative effect on BMD. The present study investigated BMD difference in normal controls and woman free-divers with vertebral fracture and with no fracture.MethodsBetween January 2010 and December 2014, traditional woman divers (known as Haenyeo in Korean), and non-diving women were investigated. The study population was divided into osteoporotic vertebral fracture and non-fracture groups. The BMD of the lumbar spine and femoral neck was measured. The radiological parameters for global spinal sagittal balance were measured.ResultsThirty free-diving women and thirty-three non-diving women were enrolled in this study. The mean age of the divers was 72.1 ± 4.7 years and that of the controls was 72.7 ± 4.0 years (P = 0.61). There was no statistical difference in BMD between the divers and controls. In divers, cervical lordosis and pelvic tilt were significantly increased in the fracture subgroup compared to the non-fracture subgroup (P = 0.028 and P = 0.008, respectively). Sagittal vertical axis was statistically significantly correlated with cervical lordosis (Spearman's rho R = 0.41, P = 0.03), and pelvic tilt (Spearman's rho R = 0.46, P = 0.01) in divers.ConclusionBMD did not differ significantly between divers and controls during their postmenopausal period. When osteoporotic spinal fractures develop, compensation mechanisms, such as increased cervical lordosis and pelvic tilt, was more evident in traditional woman divers. This may be due to the superior back muscle strength and spinal mobility of this group of women.

Cationic cotton was prepared with Girard's Reagent T through interconnecting dialdehyde linkages using glyoxal or glutaraldehyde. The presence of Girard's Reagent T in the treated cotton cellulose was confirmed by various analytical methods. Enhanced dyeability of cationized cotton was confirmed by K/S value evaluation after dyeing with acid and reactive dyes. Crosslinking was corroborated by wrinkle recovery angle measurements. The results verified different reactivities of the two dialdehydes toward cellulose and Girard's Reagent T; glyoxal was a more effective interconnecting linker than glutaraldehyde. Therefore, simultaneous treatment with dialdehyde and Girard's Reagent T provided cationic cotton, resulting in enhanced dyeability, hydrophilicity, antibacterial properties, and resilience. This process was rapid and efficient, and used non-formaldehyde reagents.

Study Design: A retrospective cross-sectional study. Objectives: The purpose of this study was to investigate osteoporosis and global sagittal alignment in the traditional women divers of Jeju Island. Summary of the Literature Review: Physical activity is beneficial to bone mineral density (BMD). Water pressure and muscle contraction may influence BMD in a positive way. However, divers experience weightlessness, which has a negative effect on BMD. Materials and Methods: Between January 2010 and December 2014, traditional women divers (known as Haenyeo in Korean), and non-diving women were investigated. The study population was divided into osteoporotic vertebral fracture and non-fracture groups. The BMD (in g/cm2) of the lumbar spine (L1–4) and femoral neck was measured using dual-energy X-ray absorptiometry. As part of the radiological assessment for global spinal sagittal balance, sagittal vertical axis, sacro-femoral distance, sagittal vertical axis to sacro-femoral distance ratio, and spino-sacral angle were measured. Results: Thirty women divers and thirty-three non-diving women were enrolled in this study. The mean age of the divers was 72.1 ± 4.7 years and that of the controls was 72.7 ± 4.0 years (P = 0.61). There was no statistical difference in BMD between the divers and controls. In the divers, there was a bigger positive sagittal balance in the fracture group compared to the non-fracture group (P = 0.001). Also in the divers, cervical lordosis and pelvic tilt were significantly increased in the fracture group compared to the non-fracture group (P = 0.028 and P = 0.008, respectively). Conclusions: Bone mineral density did not differ statistically between divers and controls during their postmenopausal period. When osteoporotic spinal fractures develop, compensation mechanisms, such as increased cervical lordosis and pelvic tilt, was more evident in traditional women divers. This may be due to the superior back muscle strength and spinal mobility of this group of women.