Introduction: Discectomy of herniated intervertebral discs (IVDs) successfully alleviates associated neurological symptoms but fails to repair the underlying degenerative disc process. Persistent annular defect post discectomy is associated with increased risk of reherniation, progressive IVD degeneration, and chronic low back pain [1-7]. Recently, we demonstrated the ability of riboflavin crosslinked high-density collagen gels (HDC) to facilitate annular repair in vivo [8,9]. In this study, AF fibrochondrocytes were seeded in the HDC gel to enhance the reparative process at the site of annular defect.
Methods: 36 athymic rats, punctured with an 18-gauge needle in the tail disc, were divided into three groups: 1) untreated (n=6); 2) injected with crossliked HDC (n=15); 3) injected with fibrochondrocyte-laden crosslinked HDC (n=15). Sheep AF fibrochondrocytes at a concentration of 106 cells/ml were mixed with HDC gels prior to injection. Quantitative analysis using X rays and MRIs [10] as well as qualitative histological assessments were performed.
Results: 36 athymic rats, punctured with an 18-gauge needle in the tail disc, were divided into three groups: 1) untreated (n=6); 2) injected with crossliked HDC (n=15); 3) injected with fibrochondrocyte-laden crosslinked HDC (n=15). Sheep AF fibrochondrocytes at a concentration of 106 cells/ml were mixed with HDC gels prior to injection. Quantitative analysis using X rays and MRIs [10] as well as qualitative histological assessments were performed.
Conclusions: In vivo studies on the cell-based annular repair are few in number. Our preliminary findings suggest that fibrochondrocytes can potentially improve HDC gel-based annular repair. Long term study with sufficient sample size are necessary to confirm these results.
Patient Care: By the conclusion of this session, participants should be able to: 1) Describe the importance of developing a novel treatment for annular defect, 2) Discuss, in small groups, therapeutic strategies using cells and scaffolds 3) Identify an effective treatment for lumbar disc hernia and subsequent degenerative disc diseases.
Learning Objectives: By the conclusion of this session, participants should be able to: 1) Describe the importance of developing a novel treatment for annular defect, 2) Discuss, in small groups, therapeutic strategies using cells and scaffolds 3) Identify an effective treatment for lumbar disc hernia and subsequent degenerative disc diseases.
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Grunert P1, Borde BH2, Towne SB1, Moriguchi Y1, Hudson KD2, Bonassar LJ3, Härtl R4. Riboflavin crosslinked high-density collagen gel for the repair of annular defects in intervertebral discs: An in vivo study. Acta Biomater. 2015 Jun 23. pii: S1742-7061(15)00271-8. doi: 10.1016/j.actbio.2015.06.006. [Epub ahead of print]
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