Canal-to-Bone Ratio as an Independent Predictor of Hip Bone Mineral Density Scores: A Retrospective Analysis

Hip fractures are a major consequence of osteoporosis. While dual-energy X-ray absorptiometry (DXA) is the gold standard for bone mineral density (BMD), radiographic indices may complement DXA. The canal-to-bone ratio (CBR)-the intramedullary canal diameter divided by the outer cortical diameter on plain radiographs-may reflect bone quality. We examined the relationship between CBR and BMD and whether CBR independently predicts hip T- and Z-scores.

The study retrospectively analyzed 90 patients with femoral radiographs and DXA. Canal-tobone ratio was measured 7 cm distal to the lesser trochanter. Lumbar and hip T-/Z-scores were recorded. Associations were tested with Pearson/Spearman correlations and linear regression; multivariable models adjusted for age.

Canal-to-bone ratio correlated negatively with hip BMD (T-score r = -0.63, P = .005; Z-score r = -0.65, P = .004), but not with lumbar scores (P > .20). Each 0.1 increment in CBR was associated with a 0.67-unit decrease in hip T-score and a 0.59-unit decrease in hip Z-score. After adjusting for age, CBR remained an independent predictor of hip T-score (β = -6.09, P = .012, R2 = 0.44) and hip Z-score (β = -5.59, P = .009, R2 = 0.43).

Canal-to-bone ratio shows a strong, independent association with hip BMD. As a simple metric obtainable from routine radiographs, CBR may serve as a surrogate marker of hip bone quality and fracture risk, particularly in settings with limited DXA access.   Cite this article as: Kaya S. Canal-to-bone ratio as an independent predictor of hip bone mineral density scores: A retrospective analysis. Eurasian J Med. 2026, 58(1), 1164, doi: 10.5152/eurasianjmed.2026.251164.