For assessment of bone remodelling around total hip arthroplasty using dual-emission X-ray absorptiometry (DEXA), a variety of different systems to identify regions of interest (ROI) have been used, making comparisons between stem designs difficult. The Gruen zones are now widely used for this purpose. We present the results of a randomised clinical trial comparing 2 uncemented stem designs with proximal coating, using a modification of the Gruen zones to allow improved representation of the effect of the implant on bone mineral density (BMD) over time.
DEXA-data were used in a randomised trial with 2 years follow up, comparing the uncemented Symax™ (n=25) and Omnifit® (n=24) stems. The effect on BMD was determined using the ‘standard’ adapted Gruen zones, and a modification which studied an equal length and position for zones 1 and 7 around both stems, assuring that the same regions in terms of cancellous and cortical bone were compared.
The ‘modified’ regions of interest give lower BMD values around the Omnifit® than using the ‘standard’ Gruen zones (3.6 % in zone 7, p<0.05). The difference with the Symax™ BMD values, which had been concealed using the standard Gruen zones, became statistically significant in favour of the Symax™ implant.
This adaptation can detect a statistically significant difference in bone preservation in zone 7 between stems that would otherwise not have been revealed. We recommend the use of ‘modified’ Gruen zones for more valid comparison of remodelling caused by different implant designs.
References
- 1.McCarthy C.K., Steinberg G.G., Agren M., Leahey D., Wyman E., Baran D.T. Quantifying bone loss from the proximal femur after total hip arthroplasty. J Bone Joint Surg Br 1991; 73: 774–8. [DOI] [PubMed] [Google Scholar]
- 2.Kilgus D.J., Shimaoka E.E., Tipton J.S., Eberle R.W. Dual-energy X-ray absorptiometry measurement of bone mineral density around porous-coated cementless femoral implants. J Bone Joint Surg Br 1993; 75: 279–87. [DOI] [PubMed] [Google Scholar]
- 3.Trevisan C., Bigoni M., Cherubini R., Steiger P., Randelli G., Ortolani S. Dual X-ray absorptiometry for the evaluation of bone density from the proximal femur after total hip arthroplasty: analysis protocols and reproducibility. Calcif Tissue Int 1993; 53: 158–61. [DOI] [PubMed] [Google Scholar]
- 4.Kiratli B.J., Heiner J.P., McBeath A.A., Wilson M.A. Determination of bone mineral density by dual X-ray absorptiometry in patients with uncemented total hip arthroplasty. J Orthop Res 1992; 10: 836–44. [DOI] [PubMed] [Google Scholar]
- 5.Cohen B., Rushton N. Accuracy of DEXA measurement of bone mineral density after total hip arthroplasty. J Bone Joint Surg Br 1995; 77: 479–83. [PubMed] [Google Scholar]
- 6.Ang K.C., Das De S., Goh J.C.H., Low S.L., Bose K. Periprosthetic bone remodelling after cementless total hip replacement. J Bone Joint Surg Br 1997; 79: 675–9. [DOI] [PubMed] [Google Scholar]
- 7.Ohta H., Kobayashi S., Saito N., Nawata M., Horiuchi H., Takaoka K. Sequential changes in periprosthetic bone mineral density following total hip arthroplasty: a 3-year follow-up. J Bone Miner Metab 2003; 21: 229–33. [DOI] [PubMed] [Google Scholar]
- 8.Herrera A., Panisello J.J., Ibarz E., Cegoñino J., Puértolas J.A., Gracia L. Long-term study of bone remodelling after femoral stem: A comparison between dexa and finite element simulation. J Biomech 2007; 40: 3615–25. [DOI] [PubMed] [Google Scholar]
- 9.Theis J.C., Beadel G. Changes in proximal femoral bone mineral density around a hydroxyapatite-coated hip joint arthroplasty. J Orthop Surg 2003; 11: 48–52. [DOI] [PubMed] [Google Scholar]
- 10.Gruen T.A., McNeice G.M., Amstutz H.C. “Modes of failure” of cemented stem-type femoral components: a radiographic analysis of loosening. Clin Orthop Relat Res 1979; 141: 17–27. [PubMed] [Google Scholar]
- 11.Zerahn B., Storgaard M., Johansen T., Olsen C., Lausten G., Kanstrup I-L. Changes in bone mineral density adjacent to two biomechanically different types of cementless femoral stems in total hip arthroplasty. Int Orthop 1998; 22: 225–9. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 12.Nishii T., Sugano N., Masuhara K., Shibuya T., Ochi T., Tamura S. Longitudinal evaluation of time related bone remodeling after cementless total hip arthroplasty. Clin Orthop Relat Res 1997; 339: 121–31. [DOI] [PubMed] [Google Scholar]
- 13.Aldinger P.R., Sabo D., Pritsch M. et al. Pattern of periprosthetic bone remodelling around stable uncemented tapered hip stems: A prospective 84-month follow-up study and a median 156-month cross-sectional study with DXA. Calcif Tissue Int 2003; 73: 115–21. [DOI] [PubMed] [Google Scholar]
- 14.Sabo D., Reiter A., Simank H.G., Thomsen M., Lukoschek M., Ewerbeck V. Periprosthetic mineralization around cementless total hip endoprosthesis: Longitudinal study and cross-sectional study on titanium threaded acetabular cup and cementless Spotorno stem with DEXA. Calcif Tissue Int 1998; 62: 177–82. [DOI] [PubMed] [Google Scholar]
- 15.Karachalios T., Tsatsaronis C., Efraimis G., Papadelis P., Lyritis G., Diakoumopoulos G. The long-term clinical relevance of calcar atrophy caused by stress shielding in total hip arthroplasty. J Arthroplasty 2004; 19: 469–75. [DOI] [PubMed] [Google Scholar]
- 16.Bodén H., Adolphson P., Öberg M. Unstable versus stable uncemented femoral stems: a radiological study of periprosthetic bone changes in two types of uncemented stems with different concepts of fixation. Arch Orthop Trauma Surg 2004; 124: 382–92. [DOI] [PubMed] [Google Scholar]
- 17.Okano T., Hagino H., Otsuka T. et al. Measurement of periprosthetic bone mineral density by dual-energy X-ray absorptiometry is useful for estimating fixation between the bone and the prosthesis in an early stage. J Arthroplasty 2002; 17: 49–55. [DOI] [PubMed] [Google Scholar]
- 18.Tanzer M., Kantor S., Rosenthall L., Bobyn J.D. Femoral remodelling after porous-coated total hip arthroplasty with and without hydroxyapatite-tricalcium phosphate coating. J Arthroplasty 2001; 16: 552–8. [DOI] [PubMed] [Google Scholar]
- 19.Rosenthall L., Bobyn J.D., Tanzer M. Bone densitometry: influence of prosthetic design and hydroxyapatite coating on regional adaptive bone remodelling. Int Orthop 1999; 23: 325–9. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 20.Kröger H., Venesmaa P., Jurvelin J., Miettinen H., Suomalainen O., Alhava E. Bone density at the proximal femur after total hip arthroplasty. Clin Orthop Relat Res 1998; 352: 66–74. [PubMed] [Google Scholar]
- 21.Muller S., Irgens F., Aamodt A. A quantitative and qualitative analysis of bone remodelling around custom uncemented femoral stems: a five-year DEXA follow-up. Clin Biomech 2005; 20: 277–82. [DOI] [PubMed] [Google Scholar]
- 22.Rahmy A.I., Gosens T., Blake G.M., Tonino A., Fogelman I. Periprosthetic bone remodelling of two types of uncemented femoral implant with proximal hydroxyapatite coating: a 3-year follow-up study addressing the influence of prosthesis design and preoperative bone density on periprosthetic bone loss. Osteoporos Int 2004; 15: 281–9. [DOI] [PubMed] [Google Scholar]
- 23.Rodan G.A. Introduction to bone biology. Bone 1992; 13: 3–6. [DOI] [PubMed] [Google Scholar]
- 24.Becker P., Zeggel P., Lüthen F., Nebe B., Rychly J., Neumann H-G. Resorbable calcium phosphate composite coatings. Bioceramics 2002; 14: 653–6. [Google Scholar]
- 25.Becker P., Neumann H.G., Nebe B., Lüthen F., Rychly J. Cellular investigations on electrochemically deposited calcium phosphate composites. J Mater Sci Mater Med 2004; 15: 437–40. [DOI] [PubMed] [Google Scholar]
- 26.Cigada A., Cabrini M., Pedeferri P. Increasing of the corrosion resistance of the Ti6Al4V alloy by high thickness anodic oxidation. J Mater Sci Mater Med 1992; 3: 408–12. [Google Scholar]
- 27.Becker P., Baumann A., Lüthen F. et al. Spark anodization on titanium and titanium alloys. Proceedings of the 10thWorld Conference on Titanium, Hamburg, Germany 2003; Vol V: 3339–44. [Google Scholar]
- 28.Broeke ten R.H.M., Alves A., Baumann A., Arts J.J.C., Geesink R.G.T. Bone reaction to a biomimetic third-generation hydroxyapatite coating and new surface treatment for the Symax hip stem. J Bone Joint Surg Br 2011; 93: 760–8. [DOI] [PubMed] [Google Scholar]
- 29.Engh C.A., Bobyn J.D., Glassman A.H. Porous coated hip replacement. The factors governing bone ingrowth, stress shielding, and clinical results. J Bone Joint Surg Br 1987; 69: 45–55. [DOI] [PubMed] [Google Scholar]
- 30.Martin R.B. The effects of geometric feedback in the development of osteoporosis. J Biomechanics 1972; 5: 447–55. [DOI] [PubMed] [Google Scholar]
- 31.Miller J.D., McCreadie B.R., Alford A.I., Hankenson K.D., Goldstein S.A. Form and function of bone. In: Einhorn T.A., O'Keefe R.J., Buckwalter J.A., eds. Orthopaedic Basic Science. 3rd ed. Chapter 8. Rosemont, Illinois: American Academy of Orthopaedic Surgeons; 2007; 129–59. [Google Scholar]