[Prevention of dura adherence in spinal canal after microendoscopic discectomy by different methods: a clinical study of 165 cases].

Objective: To evaluate the effects of different methods in prevention of post-operational scar formation and dura adherence in the spinal canal after microendoscopic discectomy (MED).

Methods: 165 patients undergoing MED were randomly divided into 3 equal groups: Group A, with the yellow ligament dissected and with the space between vertebral laminae sprinkled with sodium hyaluronate before the closing of the incision; Group B, with the yellow ligament reserved; and Group C, with the yellow ligament reserved and with the space between vertebral laminae sprinkled with sodium hyaluronate before the closing of the incision. All the patients were followed up 2, 4, and 8 weeks, and 1 and 2 years after the operation. Japanese Orthopedic Association (JOA) scoring system was used to evaluate the outcomes.

Results: The JOA scores 2 weeks after MED were not significantly different among the 3 groups; and from then on the JOA scores of Groups B and C were all higher than those of group A (A and B: t(4w) = 0.602, t(8w) = 0.701, t(1y) = 0.623, t(2y) = 0.654; A and C: t(4w) = 0.833, t(8w) = 0.759, t(1y) = 0.714, t(2y) = 0.771, all P < 0.05), however, there were not significantly differences at all time points between Groups B and C (B and C: t(2w) = 0.041, t(4w) = 0.135, t(8w) = 0.980, t(1y) = 0.530, t(2y) = 0.103, all P > 0.05). CT showed that a great amount of scar was seen, surrounding the dura mater sac and nerve roots in Group A, and there was a great amount of scar outside the yellow ligament and no remarkable compression of dura mater sac and nerve roots in Groups B and C.

Conclusion: Reservation of yellow ligament effectively prevents scar adhesion inside the vertebral canal after MED. Sprinkling of sodium hyaluronate is also effective, however, its effect only lasts a short time.