Biomechanical evaluation of different annulus fibrosus closure techniques

English Keywords:Annulus fibrosus  Suture  Intradiscal pressure  Biomechanics

English Abstract:

  【Abstract】 Objectives: To evaluate the efficacy of different techniques of repairing annulus fibrosus through biomechanical testing method. Methods: 50 lumbar spinal segments were obtained from calves, and one 10mm incision was made in each segment. Segments were randomly assigned into 5 groups according to their respective anulus closure methods: cyanoacrylate glue(group A, DermaBond), simple suture(group B, "U" suture), MPSS suture(group C, modified purse-string suture), cyanoacrylate glue+simple suture(group D) and cyanoacrylate glue+MPSS suture(group E). Quantitative discomanometry and cyclic fatigue loading were then applied to compare their leakage pressure and loading cycles, as well as the parameter of disk integrity. Results: The leakage pressure in group A-E was 0.76±0.11MPa, 1.66±0.11MPa, 1.84±0.15MPa, 1.88±0.13MPa and 2.16±0.24MPa respectively, group E was significantly higher than the other groups(P＜0.05). The number loading cycles in group A-E was 4.42±0.59, 8.06±0.75, 8.44±1.01, 9.76±0.23 and 9.88±0.21 ten thousand times respectively, except for group D, the difference between group E and the other groups was significant(P<0.05). Conclusions: Closing the anulus incision with suture or fibrin glue alone may not be appropriate, the best method is cyanoacrylate glue with MPSS suture.