Osteoporosis and cement usage in total hip arthroplasty

Cement usage in total hip arthroplasty (THA) is increasingly common. However, osteoporosis-related fracture risk in cemented vs uncemented THA patients is poorly characterized. We aim to analyze the usage of metabolic bone care and osteoporosis fracture risk in cemented vs uncemented THA patients using FRAX and radiographic bone measurements.

Chart review on 250 THA patients was performed retrospectively. Demographics, FRAX scores, hip radiograph measurements, osteoporosis diagnosis, treatment and screening were compared between cemented and uncemented THA patients. Logistic regression model was used to analyze factors influencing cement usage.

Cemented THA patients have significantly higher osteoporosis-related fracture risk as measured by FRAX major (20% vs 13%) and FRAX hip (8% vs 5%). There is no significant difference in osteoporosis treatment, vitamin D / calcium supplementation, or metabolic bone disease screening based on patients’ cement status. Female sex and rheumatoid arthritis status significantly predict cement usage, but FRAX scores do not predict cement usage. Additionally, 50% (10/20) of patients with Dorr C classification were uncemented.

Although some patients undergoing THA with high osteoporosis-related fracture risk were identified and cemented, some risk factors including poor proximal femur shape (by Dorr classification) and poor bone quality (as measured by FRAX score) were potentially overlooked. Cemented patients had an increased risk for fractures but did not receive appropriately increased osteoporosis screening or treatment.

III