The human knee is a complex biomechnaical unit. The meniscus in the knee joint is one of the most important structures and its movement has become concerns only recently. Brantigan and Voshell first reported that lateral meniscus is relatively
mere mobile than medial meniscus. Recently Thompsom and Fu using 3-dimentional MRI, reported medial meniscus moves 5.1mm in comparision to lateral meniscus moving 11.2mm with a ratio of 1:2.3.
We have studied about the movement of the meniscus as the knee joint undergoes its motion. The authers obtained 5 knee joints from the men aged between 8 and 58 years old, which were amputted above the knee because of vascular insufficiency and
studied on the medial and lateral menisci during the knee joint flexion. The steelballs with the diameter of 2mm were inserted into peripheral margins of the medial and lateral menisci and another steelballs with diameter of 3mm were put into peripheral
margins of the proximal tibia with a regular intervals.
The reontgenogram were taken serially while flexing the knee joint from 0°, 15°, 30°, 45°, 60°, 90°and to 120°and analyzed by computer graphic method.
@ES The results were as follows
@EN 1. Specimen A, C, D & E showed a ratio of movement, medial to lateral meniscus. 1.2 : 1, 1.5 : 1, 1.3 : 1 and 2.7 : 1, respectively exhibiting more mobility in lateral meniscus. But in specimen B, medial meniscus showed more mobility with
ratio
of 1
: 1.3.
2. The longest distance of movement was 12mm by the anterior horn of lateral meniscus while that of medial meniscus was 5.5mm. The shortest distance of movement was 2.8mm by the posterior horn of lateral meniscus while that of medial meniscus
was
1.9mm.
3. The average distance of movement for the anterior and posterior horn of lateral meniscus was 7.2mm and 5.1mm respectively, showing more mobility in the anterior horn.
The average distance of movement for the anterior and posterior horn of medila meniscus was 4.9mm and 3.6mm respectively and also anterior horn of medial meniscus was more mobile.
4. When comparing the movement of the menisci with the knee flexion, early phase of flexion(0°-60°) of all specimens were more mobile than late phase of flexion(60-120°) in both menisci.
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