NMR spin–spin coupling constants (scalar couplings, J-couplings) are highly abundant in saccharides, with multiple values often reporting on the same structural domain (redundancy). While conventional analyses of J-couplings typically involve studies of these parameters in relation to individual structural elements, future treatments are more likely to involve simultaneous analyses of large numbers of redundant (and in some cases correlated) J-couplings sensitive to multiple structural domains, providing a more complete appraisal of local molecular structure in solution. These analyses require quantitative relationships between J-couplings and saccharide structure. This chapter provides a detailed look at structural information encoded in one-bond (1J), two-bond (2J), three-bond (3J), four-bond (4J), and dual pathway (2+3J, 3+3J) scalar couplings involving hydrogen and carbon as coupled nuclei in saccharides. Experimental and computational data are integrated to illustrate correlations between saccharide structure, J-coupling magnitude and J-coupling sign. Topics ranging from selective isotopic labeling to enable J-coupling measurements, experimental methods to determine J-coupling magnitudes and signs, and the effects of specific types of molecular motions on the behaviors of saccharide J-couplings are treated. While work published over the past fifteen years comprise the main discussion, new data are included to augment or refine prior findings, notably on long-range 4JHH values in aldopyranosyl rings and across O-glycosidic linkages, and J-couplings pertinent to conformational analyses of glycosidic linkages.

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Study Design: Retrospective radiographic review. Objectives: Investigate and quantify transverse pedicle angle (TPA), the medial-to-lateral pedicle angulation, and its potential association with pelvic incidence (PI) in patients with isthmic lumbar spondylolisthesis (ISLS) and compare to those with degenerative lumbar spondylolisthesis (DSLS) and controls. Methods: A total of 200 patients (64 ISLS, 70 DSLS, 66 control) were included. TPA was calculated at the L3-5 vertebral levels using axial computed tomography slices. PI was measured on lateral radiographs. Two independent observers completed the measurements. As a sensitivity analysis, TPA was also measured at the most cranial and caudal aspects of the L3-5 vertebral levels of a subset of participants (29 ISLS, 31 DSLS, 35 control) and the cranial to caudal change (ΔTPA) was calculated. Results: TPA values (mean ± SD) at L4 and L5 for ISLS (L4: 17.3° ± 3.7°, L5: 26.0° ± 5.2°) were significantly higher than those for the DSLS (L4: 14.3° ± 3.8°, L5: 22.2° ± 5.0°) and control (L4: 14.5° ± 3.9°, L5: 20.7° ± 3.8°) groups. TPA in the DSLS group was significantly higher than controls at L5, but not L4. High PI predicted wider TPA at L5 in both DSLS and ISLS. ΔTPA (mean ± SD) increased sequentially proceeding through the L3-5 spinal levels for the ISLS (L3: 6.8° ± 4.4°, L4: 8.7° ± 5.2°, L5: 15.6° ± 9.0°), DSLS (L3: 8.2° ± 6.0°, L4: 8.3° ± 5.9°, L5: 18.3° ± 7.2°), and control (L3: 6.8° ± 4.4°, L4: 8.2° ± 4.7°, L5: 17.7° ± 7.0°) groups. Conclusions: TPA was significantly increased in ISLS compared with DSLS and controls. High PI significantly predicted high TPA at the L5 vertebral level in ISLS and DSLS. ΔTPA increased sequentially proceeding through the lumbar spine across groups.