Pain after osteoporotic fractures using mouse models and patient samples

Area of Science:

• Biomedical research
• Pain mechanisms
• Osteoporosis research

Background:

• Osteoporosis is linked to chronic pain, but underlying mechanisms remain unclear.
• Investigating pain behaviors and molecular markers in osteoporosis and fracture models is crucial.

Purpose of the Study:

• To explore pain behaviors and nociceptive marker expression in mouse models of osteoporosis and fracture.
• To quantify nerve markers in serum of osteoporotic patients with or without fractures and pain.

Main Methods:

• Ovariectomy (OVX) or sham surgery in mice, followed by femoral osteotomy or sham osteotomy.
• Assessment of pain behaviors, gene expression (RT-PCR) in bone and dorsal root ganglia (DRGs).
• Quantification of serum nerve markers in osteoporotic patients using ELISAs.

Main Results:

• Ovariectomy alone did not alter pain behaviors or nociceptive gene expression.
• Osteotomy and sham osteotomy affected pain behaviors, but not significantly gene expression.
• OVX prior to osteotomy worsened weight-bearing in mice.
• No correlation found between serum nerve markers and fracture pain in osteoporotic patients.

Conclusions:

• Ovariectomy and bone loss are insufficient to induce pain behaviors in mice but can exacerbate pain post-fracture.
• Clinical analysis revealed no correlation between circulating nerve markers and patient-reported fracture pain.
• Potential sex differences in pain markers warrant further investigation.