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Updated: Aug 22, 2026
Scanning Skeletal Remains for Bone Mineral Density in Forensic Contexts
Published on: January 29, 2018
Changes in bone metabolism and densitometry after metabolic/bariatric surgery: a comparison of pre- and postoperative
Daniel M Felsenreich1, Natalie Vock1, Lea Pedarnig1
1Division of Visceral Surgery, Department of General Surgery, Medical University of Vienna, Vienna, Austria.
Background:
Metabolic and bariatric surgery (MBS) is associated with sustained weight loss and metabolic improvement. However, the understanding of its long-term effects on skeletal health remains incomplete, particularly with respect to different surgical procedures.
Objectives:
This study aimed to evaluate long-term changes in bone metabolism, bone mineral density (BMD), and fracture risk after sleeve gastrectomy (SG), Roux-en-Y gastric bypass (RYGB), and one-anastomosis gastric bypass (OAGB).
Setting:
University hospital.
Methods:
In this retrospective cohort with prospective long-term follow-up, 60 patients (20 RYGB, 20 OAGB, and 20 SG) underwent primary MBS. Dual-energy X-ray absorptiometry-derived bone densitometry and bone metabolism markers were assessed preoperatively and after a mean follow-up of 10.1± 2.5 years. Measurements included BMD, T-score, and z score at lumbar spine and femoral neck. Ten-year fracture probability was estimated using the FRAX (Fracture Risk Assessment tool) score.
Results:
Bone metabolism markers largely remained within reference ranges throughout follow-up. Serum vitamin D levels increased significantly after all procedures reflecting postoperative supplementation. In contrast, significant reductions in femoral BMD was observed after all three procedures (SG: .99 ± .14 to .49 ± .17 g/cm2, P = .03; RYGB: 1.09 ± .80 to .59 ± .17 g/cm2, P = .02; OAGB: 1.11 ± .18 to .53 ± .13 g/cm2, P = .01), whereas lumbar spine BMD showed no significant change. FRAX-estimated 10-year risk for major osteoporosis and hip fractures was elevated at long-term follow-up.
Conclusions:
Despite largely preserved biochemical bone markers, substantial long-term structural bone loss and increased fracture risk were observed after MBS. These findings support the consideration of routine postoperative bone health surveillance following MBS to allow early therapeutic intervention when indicated.
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