Clinical study of vertebral compression fracture caused by primary osteoporosis and multiple myeloma

English Keywords:Primary osteoporosis  Multiple myeloma  Vertebral compression fracture  Differential diagnosis

English Abstract:

  【Abstract】 Objectives: To investigate the clinical characteristics, laboratory results, imaging findings of vertebral compression fractures caused by osteoporosis secondary to primary osteoporosis and multiple myeloma, and to analyze and summarize the differences. Methods: A total of 132 patients with vertebral compression fractures who visited the Department of Spinal and Spinal Cord Surgery of our hospital from January 2013 to January 2021 were retrospectively analyzed, including 38 patients with multiple myeloma(myeloma group) and 94 patients with primary osteoporosis(osteoporosis group) diagnosed by bone marrow aspiration pathological examination. The gender, age, body mass index(BMI), visual analogue scale(VAS) for pain, Oswestry disability index(ODI), hemoglobin content and whether anemia(hemoglobin<100g/L), albumin-globulin ratio(A/G ratio) and whether inverted, β2-microglobulin(β2-MG) content, the number and distribution of diseased vertebral bodies(cervical vertebra, thoracic vertebra, lumbar vertebra), shape(wedge, double concave, flat shape), CT density change, MRI signal(high signal intensity, isointensity, low signal intensity) and whether the pedicle and accessories of diseased vertebral bodies are involved were compared between the two groups. Laboratory tests with P<0.05 were screened and included in binary logistic regression analysis to study their relationship with the occurrence of multiple myeloma, and finally the predictive relationship between each laboratory test and the correlation of multiple myeloma was verified by receiver operating characteristic(ROC) curves. Results: There were 22 males and 72 females in the osteoporosis group, aged 73.35±10.14 years, with a body mass index of 24.20±2.72kg/m2, and 21 males and 17 females in the myeloma group, aged 59.24±10.87 years, with a body mass index of 20.30±2.81kg/m2. There were significant differences in gender, age, and body mass index between the two groups(P<0.05). In osteoporosis group, VAS score was 8.05±0.93 points, ODI score was (72.79±7.17)%, bone mineral density T-score was -3.4±0.29SD; in myeloma group, VAS score was 7.07±0.99 points, ODI was (72.79±7.17)%, bone mineral density T-score was -3.0±0.27SD. There were significant differences in VAS score, ODI and bone mineral density T-value between the two groups(P<0.05). There were 10 cases of inverted ball ratio, 2 cases of anemia, 30 cases of inverted ball ratio in myeloma group, and 33 cases of anemia in osteoporosis group. There were significant differences in inverted ball ratio and anemia between the two groups(P<0.05). β2-MG was 1.73±0.60mg/L in the osteoporosis group and 3.98±1.48mg/L in the myeloma group, and there was a significant difference in β2-MG content between the two groups(P<0.05). There was no significant difference in the distribution of diseased vertebral bodies between the two groups(P>0.05). There was significant difference in wedge and flat change of diseased vertebral body between the two groups(P<0.05), but there was no significant difference in double concave change(P>0.05). There were significant differences in the "worm-like" changes in the CT cross-section of the diseased vertebral body, angulation of the posterior edge of the diseased vertebral body, and There was no significant difference in MRI signal and pedicle involvement of the diseased vertebral body between the two groups(P>0.05). The results of logistic regression analysis showed that hemoglobin content, albumin-to-globulin ratio, and β2-MG content were independent factors for multiple myeloma prediction(P<0.05). The AUC of hemoglobin content was 0.065, the diagnostic sensitivity was 3%, the specificity was 100%, the AUC of albumin-to-globulin ratio was 0.087, the diagnostic sensitivity was 5%, the specificity was 98%, the aera under curve(AUC) of β2-MG content was 0.917, the diagnostic sensitivity was 90%, and the specificity was 97%. Conclusions: Primary osteoporotic vertebral compression fractures are rare in elderly women, and linear hypointense shadows are observed in T1WI of the diseased vertebral body; vertebral compression fractures caused by multiple myeloma occur frequently in middle-aged and elderly men, and "worm-like" dissolution destruction is observed in the CT cross-section of the diseased vertebral body. Laboratory tests often suggest anemia, inverted white/ball ratio and abnormally elevated β2-MG. Serum β2-MG can be used as a sensitive indicator for the diagnosis of multiple myeloma.