가토의 슬관절 외측 측부 인대 복원후 조기운동이 관절 안정도에 미치는 영향

Abstract

[한글]

슬관절의 인대 손상을 받았을 때 조기에 적절한 치료를 시행하지 않으면 관절 불안정성이 야기됨으로서 이차적으로 골관절염이 속발된다는 사실이 실험적으로나 임상적으로 입증되고 있다.

슬관절의 심한 인대 손상은 조기에 수술적으로 손상인대를 복원하여 주는 것이 최상의 치료법으로 권장되고 있다.

대부분의 경우 수술후 처치로서 복원된 조직의 충분한 치유를 위해 약 6주간의 외고정을 시행함이 보편화되어 실시되고 있으나, 이에는 기타 골-인대 복합체의 전반적인 약화가 초래된다는 사실이 실험적으로나 임상적으로 밝혀져 있고 또한 대퇴사두근의 근력약화

및 관절강직등의 후유증을 유발시키는 단점이 수반되며, 단지 4주만의 관절 고정후에도 관절연골 및 연골하골부에 초기 관절염의 변화가 나타나기 시작한다는 결과가 보고되고 있다. 따라서 복원된 손상인대의 치유과정을 저해시키지 않는 범위에서 관절의 조기운동

의 필요성이 현재 강조되고 있는 실정이다.

저자는 이러한 모든 점을 참작하여 실험적으로 가토의 외측 측부 인대에 손상을 가하고 수술적으로 복원한 후 조기운동을 시행함으로 이로 인한 인대의 치유과정과 슬관절의 안정도에 미치는 영향을 밝힘으로서 임상응용으로의 진일보를 도모하기 위한 목적하에 본 실험에 착수한 바 몇 가지 결과를 얻었기에 이에 보고하는 바이다.

50마리의 성숙가토의 우측 외측 측부 인대를 사용하였으며, 각 10마리씩 5군으로 나누어 실험하였고, 좌측 슬관절은 상관된 대조군으로서 건전한 상태로 남겨 두었다.

제 1군 : 외고정없이 8주간 사육장내 활동

제 2군 : 1주 석고고정후 7주간 사육장내 활동

제 3군 : 2주 석고고정후 6주간 사육장내 활동

제 4군 : 3주 석고고정후 5주간 사육장내 활동

제 5군 : 4주 석고고정후 4주간 사육장내 활동

실험결과

1. 수술적 복원후 고정기간이 길수록 슬관절의 운동장애, 주위 근육의 위축이 심하였다.

2. 복원 인대의 치유는 전체 실험군에서 염증세포를 포함한 육아조직의 침윤이 거의 없어지고 교원섬유의 성숙을 보여 주었다.

3. 내반력을 가한 방사선촬영상 측방 불안정도는 대조군에서 슬관절의 최대신전시 5.83°±1. 76°, 30°굴곡시에는 6.30°±1, 64°였으며, 각 실험군에서는 대조군에 비하여 현저한 측방 불안 정성을 보여 주었으나(p<0.001), 각 실험군간에는 통계적으로 유의한

차는 없었다.

4. 생역학적 검사상 대조군에 비하여 각 실험군에서 최대부하의 감소(37%∼43%), 에너지흡수의 감소(40%∼45%) 및 탄성도의 증가가 나타났고 강성도는 상당히 낮았다. 그러나 각 실험군간에는 통계적으로 유의한 차는 없었다.

5. 장력계에 의한 인대파열의 발생빈도가 제일 높은 부위는 대조군에서는 대퇴골 부착부(42%)였고, 실험군에서는 인대 실질부(52%)였다.

6. 대퇴골 관절연골의 퇴행성 변화는 인대 복원술후 석고고정 기간에 비례하여 관절연골의 퇴행성 변화가 심하였다.

이상의 소견을 종합하여 보면 가토의 외측 측부 인대 복원술후 사육장내에서의 조기운동은 인대의 치유과정을 방해하지 않고 또한 관절의 불안정성을 초래하지도 않으며 슬관절 운동 범위와 빠른 회복과 관절연골의 퇴행성 변화를 감소시킬 수 있을 것으로 사료된다.

Influence of Early Mobilization on Joint Stability of the Repaired Lateral

Collateral Ligament of the Knee in Rabbits

Min Lee

Department of Medical Science The Graduate School, Yonsei University

(Directed by Prof. Byeong Mun Park, M.D. )

Generally extensive ligamentous damage at the knee is best managed by early

surgical intervention, but there is disagreement in the literature concerning the

postoperative management of these injuries.

Many surgeons use external immobilization for 6 weeks to allow sufficient tissue

healing. However, it has been demonstrated in experimental animals that immobility

leads to significant weakening of the bone-ligament complex. Furthermore,

osteoarthritic changes in cartilage and subchondral bone were reported after as

little as 4 weeks of immobilization. In an effort to minimize ligament weakening

subsequent to immobilization and to promote early healing, some authorities

advocate early mobilization.

The purpose of this study was to evaluate the effect of early postoperative

mobilization on the knee joint stability after repair of the lateral collateral

ligaments in rabbits.

Fifty adult healthy rabbits were used. One hundred knee specimens (fifty left

knees, control group; fifty right knees, experimental groups) were analyzed with

regard to their mechanical behavior.

The lateral collateral ligament unit was chosen for study. The experimental

period for most groups was 8 weeks.

The animals were divided into five groups, as follows:

Group Ⅰ: Transection of the lateral collateral ligament; repair of ligament and

8 weeks cage activity

Group Ⅱ: Repaired and immobilized in plaster cast for 1 week, 7 weeks cage

activity

Group Ⅲ: Repaired and immobilized for 2 weeks, 6 weeks cage activity

Group Ⅳ: Repaired and immobilized for 3 weeks, 5 weeks cage activity

Group Ⅴ: Repaired and immobilized for 4 weeks, 4 weeks cage activity

The results are summarized as follows:

1. The immobilized knees seemed stiffer. All muscle groups appeared more severely

atrophied than the early mobilized knees after removal of cast but joint stiffness

was overcome after cage activity.

2. Grossly, at 8 weeks the lateral collateral ligament healed without excessive

external proliferation or adhesions to adjacent structures. The repair site showed

microscopic evidence of early mature collagen formation by 8 weeks, but there was

still minimum residual fibroblastic activity at this time.

3. Varus laxity of control animals averaged 5.83° 1.76° in full extension and

6.30° 1.64° in 30° flexion. Experimental knees showed an increased varus laxity

in comparison to control specimens but there was no statistical difference among

each of the experimental animals.

4. In the experimental group, the experimental unit showed a statistically

significant decrease in the maximum failure load (37%∼43%) and energy absorbed to

failure(40%∼45%)in comparison to control animals. There was a statistically

significant decrease in stiffness of the ligament unit which may also be expressed

as an increased in ligament compliance. Statistical comparison of the five

experimental groups showed no difference in the mechanical properties of the

ligaments.

5. In the control group, 42% of the specimens showed an avulsion type of failure,

where-as 52% failed by a ligamentous type in the experimental groups. The

difference in mode of failure between the control and experimental grouts was

statistically significant(p<0.05).

6. Degenerative cartilage changes were present on the femoral condyles of each

groups. These changes were more numerous and severe in the immobilized knees.

These results support the concept that in rabbits early mobilization after knee

ligament repair does not seem to compromise ligament healing or result in undue

ligament laxity. Early excercise is accepted as beneficial in preventing muscle

atrophy, maintaining joint motion, and lessening the damage to the articular

cartilage.

[영문]

Generally extensive ligamentous damage at the knee is best managed by early surgical intervention, but there is disagreement in the literature concerning the postoperative management of these injuries.

Many surgeons use external immobilization for 6 weeks to allow sufficient tissue healing. However, it has been demonstrated in experimental animals that immobility leads to significant weakening of the bone-ligament complex. Furthermore, osteoarthritic changes in cartilage and subchondral bone were reported after as little as 4 weeks of immobilization. In an effort to minimize ligament weakening subsequent to immobilization and to promote early healing, some authorities advocate early mobilization.

The purpose of this study was to evaluate the effect of early postoperative mobilization on the knee joint stability after repair of the lateral collateral ligaments in rabbits.

Fifty adult healthy rabbits were used. One hundred knee specimens (fifty left knees, control group; fifty right knees, experimental groups) were analyzed with regard to their mechanical behavior.

The lateral collateral ligament unit was chosen for study. The experimental period for most groups was 8 weeks.

The animals were divided into five groups, as follows:

Group Ⅰ: Transection of the lateral collateral ligament; repair of ligament and 8 weeks cage activity

Group Ⅱ: Repaired and immobilized in plaster cast for 1 week, 7 weeks cage activity

Group Ⅲ: Repaired and immobilized for 2 weeks, 6 weeks cage activity

Group Ⅳ: Repaired and immobilized for 3 weeks, 5 weeks cage activity

Group Ⅴ: Repaired and immobilized for 4 weeks, 4 weeks cage activity

The results are summarized as follows:

1. The immobilized knees seemed stiffer. All muscle groups appeared more severely atrophied than the early mobilized knees after removal of cast but joint stiffness was overcome after cage activity.

2. Grossly, at 8 weeks the lateral collateral ligament healed without excessive external proliferation or adhesions to adjacent structures. The repair site showed microscopic evidence of early mature collagen formation by 8 weeks, but there was still minimum residual fibroblastic activity at this time.

3. Varus laxity of control animals averaged 5.83° 1.76° in full extension and 6.30° 1.64° in 30° flexion. Experimental knees showed an increased varus laxity in comparison to control specimens but there was no statistical difference among each of the experimental animals.

4. In the experimental group, the experimental unit showed a statistically significant decrease in the maximum failure load (37%∼43%) and energy absorbed to failure(40%∼45%)in comparison to control animals. There was a statistically significant decrease in stiffness of the ligament unit which may also be expressed as an increased in ligament compliance. Statistical comparison of the five experimental groups showed no difference in the mechanical properties of the ligaments.

5. In the control group, 42% of the specimens showed an avulsion type of failure, where-as 52% failed by a ligamentous type in the experimental groups. The difference in mode of failure between the control and experimental grouts was statistically significant(p<0.05).

6. Degenerative cartilage changes were present on the femoral condyles of each groups. These changes were more numerous and severe in the immobilized knees.

These results support the concept that in rabbits early mobilization after knee ligament repair does not seem to compromise ligament healing or result in undue ligament laxity. Early excercise is accepted as beneficial in preventing muscle

atrophy, maintaining joint motion, and lessening the damage to the articular cartilage.