After bariatric surgery, hip bone loss reflects skeletal unloading and cortical bone loss reflects secondary hyperparathyroidism. This study highlights deterioration of cortical bone loss as a novel mechanism for bone loss after bariatric surgery.

At the tissue level, premenopausal women with more central adiposity had inferior bone quality and stiffness and markedly lower bone formation. Given the rising levels of obesity, these observations require further investigation.

Teriparatide was associated with increased spine and hip BMD and improved trabecular microarchitecture and stiffness at the iliac crest in the majority of women with IOP.

Higher marrow adiposity and the absence of expected relationships between marrow adiposity and bone microstructure and remodeling in women with IOP or ILBMD suggest that the relationships between fat and bone are abnormal; excess marrow fat may not arise from a switch from the osteoblast to the adipocyte lineage in this disorder. Whether excess marrow fat contributes to the pathogenesis of this disorder remains unclear.

In premenopausal women with IOP, 18 months of teriparatide was associated with increases in trabecular volumetric BMD, improved trabecular microarchitecture, and estimated bone strength at both the radius and tibia.