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Study Design: Cross-sectional., Objective: To assess the distribution of the ultra-short time-to-echo (UTE) disc sign (UDS) and its association with disc degeneration, other magnetic resonance imaging (MRI) phenotypes, pain, and disability profiles., Summary of Background Data: Disc degeneration has been conventionally assessed by T2-weighted (T2W) signal intensity on MRI; however, its clinical utility has been questionable. UTE MRI assesses short T2 components. The authors have identified a new imaging biomarker on UTE-the UDS., Methods: One hundred eight subjects were recruited. T2W MRI assessed disc degeneration and other phenotypes, and T1-rho MRI values represented quantitative proteoglycan disc profiles of L1-S1. UDS was detected on UTE (i.e., hyper-/hypointense disc band). A UDS score (cumulative number of UDS levels) and T2W summated lumbar degenerated scores (cumulative disc degeneration score) were assessed. Subject demographics, chronic low back pain (LBP), and disability profiles (Oswestry Disability Index: ODI) were obtained., Results: UDS was noted in 39.8% subjects, 61.4% occurred at the lower lumbar spine and 39.5% had multilevel UDS. UDS subjects had significantly greater severity and extent of disc degeneration, and Modic changes (P < 0.05). By disc levels, a higher prevalence of disc degeneration/displacement, Modic changes, and spondylolisthesis were noted in UDS discs than non-UDS discs (P < 0.05). T1-rho values were also lower in UDS discs (P = 0.022). The majority of UDS could not be detected on T2W. The UDS score significantly correlated with worse ODI scores (r = 0.311; P = 0.001), whereas T2W cumulative disc degeneration score did not (r = 0.13; P = 0.19). LBP subjects exhibited more multilevel UDS (P < 0.015) but not on T2W MRI (P = 0.53). The UDS score was significantly related to LBP (P = 0.009), whereas T2W cumulative disc degeneration score was not (P = 0.127)., Conclusion: This is the first study to report "UDS" in humans. UDS is a novel imaging biomarker that is highly associated with degenerative spine changes, chronic LBP, and disability than conventional T2W MRI., Level of Evidence: 2.

Purpose: Fresh frozen intervertebral disc allograft transplantation has been reported to be a viable treatment option for advanced degenerative disc diseases, but rapid degeneration of the postoperative allograft was found. Loss of nutrient supply is believed to be the most likely inducer because the disc allografts have to endure in an ischaemic environment until the nutrient pathway is re-established. The aim of this study was to focus on the revascularisation of the disc allograft after transplantation in goats., Methods: Twenty male goats were used in this study. Intervertebral disc allograft transplantation was performed at L4/L5. Groups of five goats were killed at 1.5, 6 and 12 m postoperatively, respectively. The transplanted segments were harvested, fixed, sagittally cut and decalcified for H&E staining and immunochemistry to observe the blood vessel formation at the endplates, anterior outer annulus, posterior outer annulus, inner annulus and the nucleus. The blood vessel density and the sectional vessel area were measured., Results: Blood vessels were first found in the marrow space of the bony endplate and the outer annulus at 1.5 month postoperatively. Then, they were able to penetrate to reach the cartilaginous endplate and the inner annulus after 6 months. Interestingly, the endplate area possessed the most abundant blood vessels, with the highest level of vessel density and area at the final follow-up. None of these newly formed vessels invaded the nucleus during the observation period., Conclusions: Revascularisation of the postoperative disc allograft has been determined, but its pattern was different from that in adult normal discs, suggesting that the typical nutrient diffusion pattern may be affected after transplantation.

Purpose: Vertebral endplate abnormalities may be associated with disc degeneration and, perhaps, pain generation. However, consensus definitions for endplate findings on spine MRI do not exist, posing a challenge to compare findings between studies and ethnic groups. The following survey was created to characterize the variability among the global spine community regarding endplate structural findings with respect to nomenclature and etiology., Methods: A working group within the International Society for the Study of the Lumbar Spine (ISSLS) Spinal Phenotype Focus Group was established to assess the endplate phenotype. A survey which consisted of 13 T2-weighted sagittal MRIs of the human lumbar spine illustrating the superior and inferior endplates was constructed based on discussion and agreement by the working group. A list of nomenclature and etiological terms with historical precedence was generated. Participants were asked to describe the endplates of each image and select from 14 possible nomenclatures and 10 etiological terms along with the option of free text response. The survey was entered into RedCap and was circulated throughout the ISSLS membership for data capture. Participants' demographics were also noted., Results: The survey was completed by 55 participants (87% males; 85% above 45 years of age, 39 clinicians, and 16 researchers). Sixty-eight percent of researchers and seventy-four percent of clinicians reported more than 16 and 20 years of research and clinical experience. Considerable variation existed in selection of nomenclature, etiology, and degree of severity of the endplate structural findings (reliability coefficients for single measures in each case were 0.3, 0.08, and 0.2, respectively). Sixty-seven percent regarded Modic changes as being a structural endplate finding. Approximately 84 and 80% of clinicians and researchers, respectively, agreed that a standardized endplate nomenclature and understanding the etiology is clinically important and needed., Conclusions: This study found that variations exist with respect to endplate nomenclature and etiology between clinicians and basic scientists, and paves the way for a consensus process to formalize the definitions.

Purpose: Fresh-frozen intervertebral disc (IVD) allograft transplantation has been successfully performed in the human cervical spine. Whether this non-fusion technology could truly decrease adjacent segment disease is still unknown. This study evaluated the long-term mobility of the IVD-transplanted segment and the impact on the adjacent spinal segments in a goat model., Methods: Twelve goats were used. IVD allograft transplantation was performed at lumbar L4/L5 in 5 goats; the other 7 goats were used as the untreated control (5) and for the supply of allografts (2). Post-operation lateral radiographs of the lumbar spine in the neutral, full-flexion and full-extension positions were taken at 1, 3, 6, 9 and 12 months. Disc height (DH) of the allograft and the adjacent levels was calculated and range of motion (ROM) was measured using the Cobb's method. The anatomy of the adjacent discs was observed histologically., Results: DH of the transplanted segment was decreased significantly after 3 months but no further reduction was recorded until the final follow-up. No obvious alteration was seen in the ROM of the transplanted segment at different time points with the ROM at 12 months being comparable to that of the untreated control. The DH and ROM in the adjacent segments were well maintained during the whole observation period. At post-operative 12 months, the ROM of the adjacent levels was similar to that of the untreated control and the anatomical morphology was well preserved., Conclusions: Lumbar IVD allograft transplantation in goats could restore the segmental mobility and did not negatively affect the adjacent segments after 12 months.

Low back pain (LBP) is the world's most disabling condition. Modic changes (MC) are vertebral bone marrow changes adjacent to the endplates as noted on magnetic resonance imaging. The associations of specific MC types and patterns with prolonged, severe LBP and disability remain speculative. This study assessed the relationship of prolonged, severe LBP and back-related disability, with the presence and morphology of lumbar MC in a large cross-sectional population-based study of Southern Chinese.We addressed the topographical and morphological dimensions of MC along with other magnetic resonance imaging phenotypes (eg, disc degeneration and displacement) on the basis of axial T1 and sagittal T2-weighted imaging of L1-S1. Prolonged severe LBP was defined as LBP lasting ≥30 days during the past year, and a visual analog scale severest pain intensity of at least 6/10. An Oswestry Disability Index score of 15% was regarded as significant disability. We also assessed subject demographics, occupation, and lifestyle factors.In total, 1142 subjects (63% females, mean age 53 years) were assessed. Of these, 282 (24.7%) had MC (7.1% type I, 17.6% type II). MC subjects were older (P = 0.003), had more frequent disc displacements (P < 0.001) and greater degree of disc degeneration (P < 0.001) than non-MC subjects. In adjusted models, any MC (odds ratio [OR] 1.48, 95% confidence interval [CI] 1.01-2.18), MC affecting whole anterior-posterior length (OR 1.62, 95% CI 1.04-2.51), and MC affecting 2/3 posterior length (OR 2.79, 95% CI 1.17-6.65) were associated with prolonged severe LBP. Type I MC tended to associate with pain more strongly than type II MC (OR 1.80, 95% CI 0.94-3.44 vs OR 1.36, 95% CI 0.88-2.09, respectively). Any MC (OR 1.47, 95% CI 1.04-2.10), type II MC (OR 1.56, 95% CI 1.06-2.31), MC affecting 2/3 posterior length (OR 2.96, 95% CI 1.27-6.89), and extensive MC (OR 1.95, 95% CI 1.21-3.15) were associated with disability. The strength of the associations increased with the number of MC.This large-scale study is the first to definitively note MC types and specific morphologies to be independently associated with prolonged severe LBP and back-related disability. This proposed refined MC phenotype may have direct implications in clinical decision-making as to the development and management of LBP. Understanding of these imaging biomarkers can lead to new preventative and personalized therapeutics related to LBP.