Lumbar Microdiscectomy with Preservation of Ligamentum Flavum as A Means of Preventing Epidural Fibrosis

Background: Postoperative scarring stands as the prevailing cause of failure after lumbar microdiscectomies. To avoid the formation of epidural fibrosis, several preventive measures have been recommended, including the application of fat, hemostatic sponges, amniotic membrane, and various anti-scarring barrier materials on the resection window and epidural space, as well as the use of drainage. In terms of surgical tactics, the preservation of the Ligamentum Flavum (LF) during microdiscectomy is recommended to prevent the development of fibrosis.

Objective: The aim of the research was to determine:

a) Would preserving the LF reduce the development of postoperative epidural fibrosis?

b) and whether the results of lumbar microdiscectomies with preserved LF would be improved compared to classic microdiscectomy.

Methods: Overall, 108 patients diagnosed with lumbar discogenic radiculopathy were selected from 2020 to 2022. They were randomly divided into two equal groups. The patients in Group A underwent classic microdiscectomy with preservation of the LF, while the patients in Group B underwent classic microdiscectomy. Patients were assessed with the Visual Analogue Pain Scale (VAPS) and the Oswestry Disability Index (ODI) before the surgery and 12 months after the surgery. The degree of postoperative epidural fibrosis was assessed 12 months after surgery by instrumental studies (MRI).

Results: In both groups, clinical data improved significantly 12 months after the surgery. According to ODI, pre-operative scores in Group A were 87.4 and postoperative scores were 13.2 (P 0.05); VAPS scores before the surgery were 8.4 and 1.7 after the surgery (P 0.05). In Group B, the ODI scores before the surgery were 89.1 and after the surgery were 23.1 (P 0.05); the VAPS scores before the surgery were 8.9 and after the surgery were reduced to 3.4 (P 0.05). The degree of scarring was less in Group A than in Group B.

Conclusion: The clinical results demonstrated in both groups were satisfactory. However, the group where LF was preserved revealed significantly fewer local scarring processes 12 months after surgery. The provided surgical method can be considered tissue sparing, reducing the complications caused by postoperative fibrosis and ultimately leading to a better clinical result after microdiscectomy.

Keywords:Epidural fibrosis; Ligamentum flavum; Microdiscectomy; Tissue-sparing surgery