Quantitative bone single-photon emission computed tomography imaging for uninfected nonunion: comparison of hypertrophic nonunion and non-hypertrophic nonunion

Abstract

Background Recently, a standardized uptake value (SUV) has been used to evaluate bone single-photon emission computed tomography (SPECT). The aim of this study was to investigate quantitative SPECT imaging of uninfected nonunion to compare hypertrophic nonunion and non-hypertrophic nonunion using volume-based parameters. Methods We evaluated 23 patients with uninfected nonunion who underwent SPECT acquisition 3 h after an injection of 99mTc-hydroxymethylene diphosphonate or 99mTc-methylene diphosphonate from April 2014 to November 2019. We reconstructed the acquired data and performed voxel-based quantitative analysis using the GI-BONE software. Quantitative parameters, maximum SUV (SUVmax), peak SUV (SUVpeak), and mean SUV (SUVmean) in the high and low uptake areas of nonunion were compared between hypertrophic nonunion and non-hypertrophic nonunion. The contralateral limb was used as a control, and the ratios of the quantitative parameters were calculated. Results The values for the quantitative parameters (high uptake area/low uptake area, respectively), SUVmax control ratio (12.13 ± 4.95/6.44 ± 4.71), SUVpeak control ratio (11.65 ± 4.58/6.45 ± 4.64), and SUVmean control ratio (11.94 ± 5.03/6.28 ± 4.95) for hypertrophic nonunion were higher than those for non-hypertrophic nonunion (7.82 ± 4.76/3.41 ± 2.09 (p = 0.065/0.12), 7.56 ± 4.51/3.61 ± 2.23 (p = 0.065/0.22), and 7.59 ± 5.18/3.05 ± 1.91 (p = 0.076/0.23)). Conclusions SUVmax, SUVpeak, and SUVmean control ratios obtained from bone SPECT images can quantitatively evaluate the biological activity of nonunions and may be an effective evaluation method for treatment decisions, especially the necessity of autologous bone grafting.

Human Non-Hypertrophic Nonunion Tissue Contains Osteoblast Lineage Cells and E-BMP-2 Activates Osteogenic and Chondrogenic Differentiation

“…The results suggested that the NHNCs have characteristics similar to those of cells from both hypertrophic nonunion and pseudoarthrosis tissues, which have been shown to resemble BMSCs [ 6 , 7 ]. However, the results of Alizarin Red S staining compared with the RIA-derived cells revealed that the NHNCs were less calcified than the BMSCs, which might explain why NHNCs do not show callus formation on X-ray findings [ 5 ]. Based on the results of the real-time RT-PCR, we consider that this might also occur because the expression of OSX , BSP , and OCN is not upregulated.…”

“…Non-hypertrophic nonunion was defined as nonunion without radiological callus formation including oligotrophic, comminuted (torsion-wedge, dystrophic, and necrotic), defect, and atrophic types in the Weber and Cech classification and was confirmed by three senior orthopedic trauma surgeons [ 3 , 5 ]. Five patients with non-hypertrophic nonunion surgically treated in our institution were enrolled ( Table 1 ).…”

“…Recently, considering the ease of judgment in clinical settings, we defined nonunion without radiological callus formation including oligotrophic, comminuted (torsion-wedge, dystrophic, and necrotic), defect, and atrophic types in the Weber and Cech classification as non-hypertrophic nonunion [ 3 , 4 ]. Furthermore, we previously reported that the standardized uptake value on bone single-photon emission computed tomography is lower in non-hypertrophic than in hypertrophic nonunion [ 5 ].…”

Influence of Metal Implants on Quantitative Evaluation of Bone Single-Photon Emission Computed Tomography/Computed Tomography

“…The presence of marked callus formation around the nonunion site typically indicates biological activity; however, in cases without callus formation, it is very difficult to determine the existence of biological activity using only X-ray findings. We previously quantified nonunion fracture repair in terms of the standardized uptake value (SUV) of single-photon emission computed tomography (SPECT) in hypertrophic and non-hypertrophic nonunions [6]. We found high SUVs in cases of non-hypertrophic nonunion, which usually exhibit poor biological activity.…”

“…This finding suggests the existence of biological activity. Therefore, we believe that bone SPECT quantification will be useful in autologous bone grafting during nonunion surgery [6,7].…”