Percutaneous Transforaminal Endoscopic Diskectomy for Lumbar Disk Herniation: Young (Age <60 years) versus Older (Age ≥60 years) Patients

Background We compare the differences in the efficacy of percutaneous transforaminal endoscopic diskectomy (PTED) between the younger (age <60 years) and older (age ≥60 years) patients with lumbar disk herniation (LDH). Methods From December 2016 to December 2017, 128 patients with symptomatic LDH underwent PTED and were followed up. Forty-four 60 years old and above, including 19 males and 25 females with an average age of 68.7 (61–82) years, were classified as the elderly age group. Eighty-four patients younger than 60 years were classified as the young age group, which included 48 males and 36 females with an average age of 44.7 (16–58) years. The visual analog scale (VAS) scores, Japanese Orthopaedic Association (JOA) scores, and satisfaction rates of the two groups before and after surgery were compared. Results The operation was completed successfully in both groups. The average follow-up times of the elderly and young age groups were 18.47 ± 2.62 (12–23) and 17.90 ± 3.27 (12–23) months, respectively. One patient in the young age group had recurrence 7 months after surgery, and the symptoms were relieved after PTED was performed again. Two patients with nerve root injury after surgery in the young age group completely recovered after 2 months of conservative treatment. There were no significant surgical complications in the elderly age group. There was no significant difference in postoperative VAS, JOA, and MacNab scores between the two groups. The MacNab scores in the elderly age group were excellent for 28 patients, good for 10 patients, and fair for 6 patients; the satisfaction rate was 86.3%. In the young age group, scores were excellent for 63 patients, good for 14 patients, fair for 5 patients, and poor for 2 patients; the satisfaction rate was 91.7%. Conclusion The clinical effectiveness of PTED for treatment of LDH in both elderly and young patients is satisfactory. Age is not a predictor of poor outcomes of PTED.

Expression of Estrogen Receptor Alpha and Evaluation of Histological Degeneration Scores in Fibroblasts of Hypertrophied Ligamentum Flavum: A Qualitative Study

The most common spinal disorder in elderly is lumbar spinal stenosis (LSS), resulting partly from ligamentum flavum (LF) hypertrophy. Its pathophysiology is not completely understood. The present study wants to elucidate the role of estrogen receptor α (ER α) in fibroblasts of hypertrophied LF. LF samples of 38 patients with LSS were obtained during spinal decompression. Twelve LF samples from patients with disk herniation served as controls. Hematoxylin & Eosin (H&E) and Elastica stains and immunohistochemistry for ER α were performed. The proportions of fibrosis, loss and/or degeneration of elastic fibers and proliferation of collagen fibers were assessed according to the scores of Sairyo and Okuda. Group differences in the ER α and Sairyo and Okuda scores between patients and controls, male and female sex and absence and presence of additional orthopedic diagnoses were assessed with the Mann–Whitney U test. There was a tendency towards higher expression of ER α in LF fibroblasts in the hypertrophy group (p = 0.065). The Sairyo and Okuda scores were more severe for the hypertrophy group but, in general, not statistically relevant. There was no statistically relevant correlation between the expression of ER α and sex (p = 0.326). ER α expression was higher in patients with osteochondrosis but not statistically significant (p = 0.113). In patients with scoliosis, ER α expression was significantly lower (p = 0.044). LF hypertrophy may be accompanied by a higher expression of ER α in fibroblasts. No difference in ER α expression was observed regarding sex. Further studies are needed to clarify the biological and clinical significance of these findings.

Diagnostic accuracy of color-coded virtual noncalcium reconstructions derived from portal venous phase dual-energy CT in the assessment of lumbar disk herniation

Objectives To investigate the diagnostic accuracy of color-coded contrast-enhanced dual-energy CT virtual noncalcium (VNCa) reconstructions for the assessment of lumbar disk herniation compared to unenhanced VNCa imaging. Methods A total of 91 patients were retrospectively evaluated (65 years ± 16; 43 women) who had undergone third-generation dual-source dual-energy CT and 3.0-T MRI within an examination interval up to 3 weeks between November 2019 and December 2020. Eight weeks after assessing unenhanced color-coded VNCa reconstructions for the presence and degree of lumbar disk herniation, corresponding contrast-enhanced portal venous phase color-coded VNCa reconstructions were independently analyzed by the same five radiologists. MRI series were additionally analyzed by one highly experienced musculoskeletal radiologist and served as reference standard. Results MRI depicted 210 herniated lumbar disks in 91 patients. VNCa reconstructions derived from contrast-enhanced CT scans showed similar high overall sensitivity (93% vs 95%), specificity (94% vs 95%), and accuracy (94% vs 95%) for the assessment of lumbar disk herniation compared to unenhanced VNCa images (all p > .05). Interrater agreement in VNCa imaging was excellent for both, unenhanced and contrast-enhanced CT (κ = 0.84 vs κ = 0.86; p > .05). Moreover, ratings for diagnostic confidence, image quality, and noise differed not significantly between unenhanced and contrast-enhanced VNCa series (all p > .05). Conclusions Color-coded VNCa reconstructions derived from contrast-enhanced dual-energy CT yield similar diagnostic accuracy for the depiction of lumbar disk herniation compared to unenhanced VNCa imaging and therefore may improve opportunistic retrospective lumbar disk herniation assessment, particularly in case of staging CT examinations. Key Points • Color-coded dual-source dual-energy CT virtual noncalcium (VNCa) reconstructions derived from portal venous phase yield similar high diagnostic accuracy for the assessment of lumbar disk herniation compared to unenhanced VNCa CT series (94% vs 95%) with MRI serving as a standard of reference. • Diagnostic confidence, image quality, and noise levels differ not significantly between unenhanced and contrast-enhanced portal venous phase VNCa dual-energy CT series. • Dual-source dual-energy CT might have the potential to improve opportunistic retrospective lumbar disk herniation assessment in CT examinations performed for other indications through reconstruction of VNCa images.

P.218 Patient reported outcomes following surgery for lumbar disk herniation: comparison of a universal and multitier health care system.

Background: Canada has a universal health care system that is funded by the government while the United States utilizes a combined public and private payer system. The purpose of this study is to investigate whether there are differences in clinical outcomes between those surgically treated for lumbar disk herniation in Canada as compared to the United States. Methods: Surgical lumbar disk herniation patients enrolled in the Canadian Spine Outcome Research Network (CSORN) prospective registry. were compared with the surgical cohort enrolled in the Spine Patients Outcome Research Trial (SPORT) study. Spine-related patient reported outcomes (PROs) were compared at 3 months and 1 year. Results: The CSORN cohort consisted of 443 patients and the SPORT cohort was made up of 573 patients. Patients in the CSORN cohort were older (p<0.001), and were more likely to be employed (p=0.003). The CSORN cohort demonstrated significantly greater rates of satisfaction after surgery at 3 months (87.2% vs. 65.5%, p=0.003) and 1 year (85.6% vs. 69.0%, p<0.0001). The CSORN cohort was a significant independent predictor of patient satisfaction at 1 year. Conclusions: Patients undergoing surgical treatment for lumbar disc herniation in Canada reported higher rates of satisfaction at 3 months and 1 year post-operatively compared to the United States.