Conversion of osteoporotic-like vertebral fracture severity score to osteoporosis T-score equivalent status: A framework study for older Chinese men

Objectives

To define what portion of older community men with what severity of radiographic osteoporotic-like vertebral fracture (OLVF) correspond to what low T-score status.

Methods

There were 755 community Chinese men (age: 76.4 ± 6.7 years) with thoracic and lumbar spine radiographs, and hip and lumbar spine bone mineral density measures. For each vertebra in a subject, a score of 0, -0.5, −1, −1.5, −2, −2.5, and −3 was assigned for no OLVF or OLVF of <20%, ≥ 20–25%, ≥ 2 5%–1/3, ≥ 1/3–40%, ≥ 40%–2/3, and ≥ 2/3 vertebral height loss, respectively. OLVFss was defined as the summed score of vertebrae T4 to L5. OLVFss and T-scores were ranked from the smallest to the largest values.

Results

OLVFss of −2, −2.5, −3, corresponded to a mean femoral neck T-score of −2.297 (range: -2.355∼-2.247), −2.494 (range: -2.637∼ −2.363), and −2.773 (range: -2.898∼-2.643), a mean hip T-score of-2.311 (range: -2.420∼-2.234), −2.572 (range: -2.708∼-2.432), −2.911 (range: -3.134∼-2.708), a mean lumbar spine T-score of −2.495 (range: -2.656∼-2.403), −2.931 (range: -3.255∼-2.664), and −3.369 (range: -3.525∼-3.258). The Pearson correlation value of OLVFss and T-score of femoral neck, hip and lumbar spine was r = 0.21, 0.26, and 0.22 (all P < 0.0001).

Conclusions

A single severe grade radiological OLVF (≥ 40% height loss) or OLVFss ≤ −2.5 suggest the subject is osteoporotic, and a single collapse grade (≥ 2/3 height loss) OLVF or OLVFss ≤ −3 meets osteoporosis diagnosis criterion. The results highlight the difficulty of diagnosing osteoporotic vertebral fractures among Chinese older men.