The Impact of Degenerative Spinal Changes on the Correlation of Peripheral and Axial Bone Density^[*]

Summary

Results of bone density measurements by quantitative computed tomography of the peripheral skeleton (pQCT) were compared with those of measurements at the axial skeleton with a view to study the effects of degenerative spinal changes on the validity of bone densitometry of the lumbar spine. 556 consecutive patients were examined by dual-energy x-ray absorptiometry (DXA) of the spine and by peripheral quantitative computed tomography (pQCT) of the distal radius. There were significant differences between the bone mineral values at the distal radius and those at the spine, depending on the degree of spinal degeneration. As expected, spinal degenerations showed a highly significant age dependence. With increasing degeneration the correlations between the radius total bone mineral concentration and the bone density of the lumbar spine decreased from r = 0.45 to 0.23 in women and from r = 0.64 to 0.28 in men. We conclude that the value of spinal DXA is reduced in patients with degenerative spinal disease, compared to the pQCT at the peripheral skeleton.

Zusammenfassung

Knochendichtemessungen mit der quantitativen Computertomographie am peripheren Skelett (pQCT) wurden mit Messungen der Knochendichte am Achsenskelett verglichen, um festzustellen, wie degenerative Veränderungen an der Wirbelsäule sich auf die Validität der Knochendichtemessungen an der Lendenwirbelsäule auswirken. 556 aufeinanderfolgende Patienten wurden mit der Zweienergie-Röntgenabsorptiometrie (DXA) an der Wirbelsäule und mit der peripheren quantitativen Computertomographie am Radius untersucht. Wir fanden in Abhängigkeit vom Schweregrad degenerativer Veränderungen signifikante Unterschiede zwischen den Knochendichtewerten am Radius und an der Wirbelsäule. Wie zu erwarten war, zeigten die degenerativen Veränderungen der Wirbelsäule eine hochsignifikante Altersabhängigkeit. Die Korrelationen zwischen der Gesamtdichte am Radius und der Knochendichte der Wirbelsäule nahmen von r = 0,45 auf r = 0,23 bei den Frauen und von r = 0,64 auf r = 0,28 bei den Männern ab. Unsere Ergebnisse zeigen, daß im Vergleich mit der pQCT am peripheren Skelett die DXA bei Patienten mit degenerativen Veränderungen der Wirbelsäule von eingeschränktem Wert ist.

Key words

Dual-energy x-ray absorptiometry (DXA) - peripheral quantitative computed tomography (pQCT) - bone density - spinal degeneration - osteoporosis

Schlüsselwörter

Zweienergie-Röntgenabsorptiometrie (DXA) - periphere quantitative Computertomographie (pQCT) - Knochendichte - Wirbelsäulendegeneration - Osteoporose

• Literatur

• 1 Börner W, Grehn S, Moll E, Rauh E. A ¹²⁵I Profile scanner for measuring bone density in the fingers. German Medical Monthly 1969; 14: 1-12.
• 2 Börner W, Schneider P. Letter to the Editor. DEXA: Diagnostic and Therapeutic Technology Assessment (DATTA). Cole HM. (ed). JAMA 1992; 268: 474-5.
• 3 Cann CE, Rutt BK, Genant HK. Effect of extraosseous calcification on vertebral mineral measurement. Calcif Tissue Int 1983; 35: 667.
• 4 Cummings SR, Black DM, Nevitt MC. et al. Bone density at various sites for prediction of hip fractures. Lancet 1993; 341: 72-5.
• 5 Dequeker J, Goris P, Uytterhoeven R. Osteoporosis and osteoarthritis (osteoarthrosis): anthropometric distinctions. JAMA 1983; 249: 1448-52.
• 6 Dequeker J, Burssens A, Creytens G, Bouillon R. Ageing of bone: its relation to osteoporosis and osteoarthrosis in postmenopausal women. Estrogens in the Postmenopause. Front Horm Res 1975; 3: 116-30.
• 7 Drinka PJ, DeSmet AA, Bauwens SF, Rogot A. The Effect of Overlying Calcification on Lumbar Densitometry. Calcif Tissue Int 1992; 50: 507-10.
• 8 Fischer M, Kempers B. Phantom studies in osteoporosis. Europ J Nucl Med 1993; 20: 434-9.
• 9 Frohn J, Wilken T, Falk S, Stutte HJ, Kollath J, Hör G. Effect of Aortic Sclerosis on Bone Mineral Measurements by Dual-Photon Absorptiometry. J Nucl Med 1991; 32: 259-62.
• 10 Hangartner TN, Johnston CC. Influence of fat on bone measurements with dual-energy absorptiometry. Bone and Mineral 1990; 9: 71-81.
• 11 Hangartner TN, Overton TR. Quantitative Measurement of Bone Density Using Gamma-Ray Computed Tomography. J Comput Assist Tomogr 1982; 6: 1156-62.
• 12 Hopkins A, Zylstra S, Hreshchyshyn MM, Anbar M. Normal and Abnormal Features of the Lumbar Spine Observed in Dual Photon Absorptiometry Scans. Clinical Nuclear Medicine 1989; 14: 410-4.
• 13 Hosie CJ, Hart DM, Smith DAS, Al-Azzawi F. Differential effect of long term estrogen therapy on trabecular and cortical bone. Ma-turitas 1989; 11: 137-45.
• 14 Krolner B, Berthelsen B, Nielsen SP. Assessment of vertebral osteopenia. Acta Radiol Diagn 1982; 23: 517-21.
• 15 Lehmann R, Wapniarz M, Kvasnicka HM, Baedecker S, Klein K, Allolio B. Reproducibility of bone mineral density of the distal radius with a special-purpose computed tomography scanner. Radiologe 1992; 32: 177-81.
• 16 Link J, Zwaan M, Weiss H-D, Borgis KJ, Bätge B. Early results of lumbar dual energy x-ray absorptiometry (DEXA) compared with dual energy quantitative computer tomography (DE-QCT). RöFo 1993; 158: 475-8.
• 17 Orwoll ES, Oviatt SK, Mann T. The Impact of Osteophytic and Vascular Calcifications on Vertebral Mineral Density Measurements in Men. J Clin Endocrinol Metab 1990; 70: 1202-7.
• 18 Overgaard C, Hansen MA, Riis BJ, Christiansen C. Discriminatory Ability of Bone Mass Measurements (SPA) and (DEXA) for Fractures in Elderly Postemenopausal Women. Calcif Tissue Int 1992; 50: 30-5.
• 19 Reid IR, Evans MC, Ames R, Wattie DJ. The influence of Osteophytes and Aortic Calcification on Spinal Mineral Density in Postmenopausal Women. J Clin Endocrinol Metab 1991; 72: 1372-4.
• 20 Reiners C, Arnold A, Brust S, Sonnenschein W. Precision of Bone Mineral Measurement with the new QCT-Scanner Stratec SCT 900. J Nucl Med 1990; 31: 856.
• 21 Reiners C. Quantitative determination of the bony tissue: state of the art. Medizinisch-Orthopädische Technik 1992; 112: 138-46.
• 22 Resnick D, Niwayama G. Degeneration disease of the spine. In: Diagnosis of bone and joint disorders. Resnick D, Niwayama G. (eds). Philadelphia: Saunders; 1981: 1374-80.
• 23 Ross PD, Davis JW, Wasnich RD, Vogel JM. The clinical use of serial bone mass measurements. Bone and Mineral 1991; 12: 189-99.
• 24 Rüegsegger P, Dambacher MA, Rüegsegger E, Fischer JA, Anliker M. Bone Loss in Premenopausal and Postmenopausal Women. Bone J and Surg 1984; 66: 1015-23.
• 25 Schneider P, Börner W. Ability of peripheral QCT at the radius in comparison to DEXA of the spine to diagnose vertebral fractures in postmenopausal women. Christiansen C. and Overgaard (eds). Osteoporosis 1990; 2: 921-4.
• 26 Schneider P, Börner W. Periphere Quantitative Computertomographie zur Knochenmineralmessung mit einem neuen speziellen QCT-Scanner. RÖFO 1991; 153: 61-9.
• 27 Schneider P, Börner W, Rendl J, Eilles C, Schlisske K, Scheubeck M. Significance of Two Different Bone Mineral Measurement Methods in the Assessment of the Peripheral and Axial Skeleton. Z Orthop 1992; 130: 16-21.
• 28 Schneider P, Börner W. Indications for bone density measurements and critical review of recurrent procedures. Der Nuklearmediziner 1990; 13: 83-91.
• 29 Schneider P, Börner W. Letter to the Editor. Bone density for prediction of hip fracture. Lancet 1993; 341: 962-3.
• 30 Schneider P, Mazess RB, Barden H. The relationship of peripheral to axial bone density. Bone and Mineral 1988; 4: 279-87.
• 31 Spitz J, Stöcker M, Ordu Y. Beeinflussung von DPA/DXA-Meßwerten durch degenerative Wirbelsäulenveränderungen. Nucl Med 1992; 31: A89.
• 32 Uebelhart D, Duboef F, Meunier PJ, Del-mas PD. Lateral Dual-Photon-Absorptio-metry: A New Technique to Measure the Bone Mineral Density at the Lumbar Spine. J Bone Min Res 1990; 5: 525-31.
• 33 Valkema R, Verheij LF, Blokland JAK, Zwinderman AH, Bijvoet OLM, Papapou-los SE, Pauwels EKJ. Limited Precision of Lumbar Spine Dual-Photon Absorptiometry by Variations in the Soft-Tissue Background. J Nucl Med 1990; 31: 1774-81.
• 34 Verstraeten A, Van Ermen H, Haghebaert G, Nijs J, Geusens P, Dequeker J. Osteoarthrosis Retards the Development of Osteoporosis. Clinical Orthopaedics 1991; 264: 169-77.