Answer to the Letter to the Editor of A. Gardner concerning “Loss of apical vertebral derotation in adolescent idiopathic scoliosis: 2-year follow-up using multi-planar reconstruction computed tomography” (by G. Cui, K. Watanabe, Y. Nishiwaki, N. Hosogane, T. Tsuji, K. Ishii, M. Nakamura, Y. Toyama, K. Chiba, M. Matsumoto; Eur Spine J (2012) Jun;21(6):1111–20. doi:10.1007/s00586-012-2633-0)

Abstract

Cobb angle of immediate after surgery and that of postoperative 2 years was 2.5 ± 1.58 [5]. The loss was significant when analyzed using paired t test. However, the change had no clinical impact when evaluated by SRS-22 scores. Based on our previous study, the coefficient of variations for intra-observer measurement was 2.3 % for the MT curve [6] using a digital measurement software on appropriately adjusted X-ray films [7,8], and by selecting the same end vertebra in each patient at different time course [9]. In this study, we also used CT scans to demonstrate the correction loss in the axial plane and, in doing so, we tried to minimize measurement errors caused by patient positioning during CT examination using the relative AVR (rAVR), which was defined as the difference between the axial rotation angle of the upper instrumented vertebra and the apical vertebra. As a result, we also found a small but significant time-interval difference in rAVR.As Dr. Gardner mentioned, some error will occur at the time of taking X-ray caused by positioning of the trunks, which is somewhat unavoidable. However, combining the results of radiographic and CT measurements, we can conclude that some correction loss may occur even if we use biomechanically stable pedicle screw constructs for adolescent idiopathic scoliosis. Although this small correction loss does not have significant clinical impact, we should be aware of this phenomenon.Acknowledgments Finally, we would like to appreciate to Dr. Gardner for his comments again.

Development of Novel System Combining Scanning Tunneling Microscope-Based Cathodoluminescence and Electroluminescence Nanospectroscopies

“…FP induced STM-CL and its collection by FP is reported in detail in our future publication. 30) In order to demonstrate the STM-EL nanospectroscopy, p-AlGaAs/i-GaAs/n-AlGaAs heterostructures were prepared by MOVPE, which contain Zn-doped p-Al x Ga 1Àx As layer, non-doped i-GaAs layer, and Si-doped n-Al x Ga 1Àx As layer (x ¼ 0:48). Figure 3 shows macroscopic EL spectra of p-AlGaAs/i-GaAs/n-AlGaAs double heterostructure (110) cross-section collected by twin-lenses which are measured under different forward bias voltage, V FW , and forward current, I FW .…”

Microstructure and Properties of Forged CoCrMo Alloy for Load Bearing Application

“…Though application of as-cast or annealed CoCrMo alloys are frequently subjected to practical use, there are possibilities of exhibition of insufficient mechanical properties due to coarse microstructure and solidification defects; for instance, microvoids, segregation of solute atoms, and so on. These often lead to premature failure of implants [5,6]. Hence, the improvement of tensile and fatigue properties of this alloy is eagerly anticipated because further mechanical reliability is required for providing long-term use for load bearing application [5].…”

“…These often lead to premature failure of implants [5,6]. Hence, the improvement of tensile and fatigue properties of this alloy is eagerly anticipated because further mechanical reliability is required for providing long-term use for load bearing application [5].…”