Effects of a Temperature-sensitive, Anti-adhesive Agent on the Reduction of Adhesion in a Rabbit Laminectomy Model

Abstract

Background: A common cause of failure in laminectomy surgery is when epidural, peridural, or perineural adhesion occurs postoperatively. The technical difficulties presented by epidural fibrosis or adhesion tissue can cause longer operation times, iatrogenic nerve root injury, and dural tears. Consequently, many spinal surgeons utilize classic strategies to reduce or prevent the adhesion, such as the use of biological or nonbiological barrier materials at the end of the laminectomy just before soft tissue closure.

Purpose: The purpose of this study is to examine the efficacy of a temperature-sensitive, anti-adhesive agent (TSAA agent), Guardix-SG®, as a mechanical barrier for the prevention or reduction of peridural scar adhesion in a rabbit laminectomy model.

Materials and Methods: Twenty-six mature New Zealand White rabbits were used for this study. Each rabbit underwent two separate laminectomies at lumbar vertebrae L3 and L6. Each of the two laminectomy sites was treated differently: (1) At the lumbar vertebra L3 laminectomy site, the defect was left empty and covered by a re-approximation of soft tissue and skin (the control group), and (2) at the lumbar vertebra L6 laminectomy site, 2 mL of the TSAA agent was applied to the dura (the experimental group). Six weeks after the operations, the experimental animals were killed. Invasive scar formation or inflammation after laminectomy was quantitatively evaluated by measuring the thickness of the dura, the distance from the surface of dura to the scar tissues, the number of inflammatory cells in the scar tissues at the laminectomy site, and the concentration of collagen in histological sections.

Results: At 6 weeks postsurgery, the dura was significantly thinner in the experimental group than in the control group (p = 0.04), and the distance from the surface of dura to the scar tissues was also significantly greater in the experimental group than in the control group (p = 0.01). The number of inflammatory cells was not significantly different in the two groups (p = 0.08), although the mean number of inflammatory cells was relatively lower in the experimental group than in the control group. In addition, the concentration of collagen was significantly less in the experimental group than in the control group (p = 0.02).

Conclusion: The current study suggests that the TSAA agent, Guardix-SG®, could be useful as an interpositional physical barrier after laminectomy for the prevention or reduction of adhesion. |연구 배경 척추 후궁 절제술 후 경막외 유착은 척추 수술 실패 증후군과 밀접한 관계가 있는 것으로 알려져 있다. 또한 척추 재수술 시, 경막외 유착은 수술의 난이도를 높이고, 수술 중 의인성 신경근 손상 및 경막 손상의 위험성을 증가시킨다. 따라서 많은 외과의들은 경막외 유착을 최소화 하기 위해 노력하고 있으며, 그 중 여러 가지 물질들을 이용한 유착 방지제의 연구가 활발히 진행되고 있다.

목적 본 연구의 목적은 토끼 척추 후궁 절제술 유착 모델을 통해 열감응성 유착 방지제 (temperature-sensitive, anti-adhesive agent; TSAA agent) Guardix-SG® 의 유착 방지 효과에 대해 평가하는 것이다.

대상 및 방법 총 26 마리의 실험용 토끼가 사용되었으며, 각각의 토끼는 요추 3번과 요추 6번에 척추 후궁 절제술을 시행하였다. 대조군으로 요추 3번 척추 후궁 절제술을 시행한 곳은 아무것도 넣지 않았으며, 실험군으로 요추 6번 척추 후궁 절제술을 시행한 곳은 2 mL의 TSAA agent를 투여한 상태로 상처를 봉합하였다. 수술 후 6주 뒤 실험에 사용한 토끼를 안락사 시킨 다음, 척추 후궁 절제술 후 경막외 유착의 정도에 대해 평가하기 위해 조직학적으로 경막의 두께, 경막과 상처 조직간 거리, 염증 정도, 콜라겐 농도를 측정하였다.

결과 척추 후궁 절제술을 시행한 상처 부위의 조직을 관찰한 결과 경막의 두께에서 통계학적으로 유의하게 대조군은 실험군보다 두꺼웠으며, 실험군은 정상과 가까운 경막 두께로 치유가 되는 것을 확인할 수 있었고 대조군에서는 두께가 증가한 것을 알 수 있었다. 경막과 상처 조직간의 거리에서는 대조군이 실험군에 비해 통계학적으로 유의하게 짧았으며 이는 TSAA agent가 경막과 상처 조직간의 거리를 유지시켜주어 유착을 방지해 주는 역할을 하는 것으로 판단된다. 염증 정도는 두 군 사이에 통계학적으로 유의한 차이는 없었으나, 실험군의 평균치가 대조군의 평균치보다 상대적으로 낮았다. 섬유화에 의한 콜라겐 농도의 비교에서 실험군이 대조군에 비해 통계학적으로 유의하게 낮았으며, 대조군에서 좀 더 많은 콜라겐이 형성된 것으로 나타나 실험군에서 섬유화가 덜 진행된 것으로 확인되었다.

결론 본 연구를 통하여 열감응성 유착 방지제 Guardix-SG®는 척추 후궁 절제술 후 경막과 경막 외부의 유착을 방지하는 유착방지제로서 훌륭한 후보재료가 되리라 판단된다.; Background: A common cause of failure in laminectomy surgery is when epidural, peridural, or perineural adhesion occurs postoperatively. The technical difficulties presented by epidural fibrosis or adhesion tissue can cause longer operation times, iatrogenic nerve root injury, and dural tears. Consequently, many spinal surgeons utilize classic strategies to reduce or prevent the adhesion, such as the use of biological or nonbiological barrier materials at the end of the laminectomy just before soft tissue closure.

Purpose: The purpose of this study is to examine the efficacy of a temperature-sensitive, anti-adhesive agent (TSAA agent), Guardix-SG®, as a mechanical barrier for the prevention or reduction of peridural scar adhesion in a rabbit laminectomy model.

Materials and Methods: Twenty-six mature New Zealand White rabbits were used for this study. Each rabbit underwent two separate laminectomies at lumbar vertebrae L3 and L6. Each of the two laminectomy sites was treated differently: (1) At the lumbar vertebra L3 laminectomy site, the defect was left empty and covered by a re-approximation of soft tissue and skin (the control group), and (2) at the lumbar vertebra L6 laminectomy site, 2 mL of the TSAA agent was applied to the dura (the experimental group). Six weeks after the operations, the experimental animals were killed. Invasive scar formation or inflammation after laminectomy was quantitatively evaluated by measuring the thickness of the dura, the distance from the surface of dura to the scar tissues, the number of inflammatory cells in the scar tissues at the laminectomy site, and the concentration of collagen in histological sections.

Results: At 6 weeks postsurgery, the dura was significantly thinner in the experimental group than in the control group (p = 0.04), and the distance from the surface of dura to the scar tissues was also significantly greater in the experimental group than in the control group (p = 0.01). The number of inflammatory cells was not significantly different in the two groups (p = 0.08), although the mean number of inflammatory cells was relatively lower in the experimental group than in the control group. In addition, the concentration of collagen was significantly less in the experimental group than in the control group (p = 0.02).

Conclusion: The current study suggests that the TSAA agent, Guardix-SG®, could be useful as an interpositional physical barrier after laminectomy for the prevention or reduction of adhesion.