Dienst Michael, Seil Romain, Gödde Stefan, Brang Michael, Becker Kurt, Georg Thomas, Kohn Dieter
Department for Orthopedic Surgery, University Hospital, Homburg/Saar, Germany.
Arthroscopy. 2002 Oct;18(8):865-71. doi: 10.1053/jars.2002.36120.
To quantify the effects of traction alone and in combination with distension of air in different joint positions in order to find out the conditions for adequate distraction of the hip joint with minimal traction force.
Experimental cadaver study.
Eight cadaver hip joints were studied. The cadavers were placed supine on a fracture table and traction was applied in different joint positions for flexion and abduction with and without distension using air. For the measurement, the joint space between the acetabulum and femoral head was separated by 4 different lines characterizing the lateral margin of the acetabulum, the superior portions of the lunate cartilage, and the acetabular fossa.
At all measurement lines, distraction of the hip was significantly better when traction and distension were combined. At traction forces from 250 to 300 N, traction plus distension resulted in a 1.59- to 2.25-fold increase of joint distraction compared to traction alone. The maximum effect of distension was achieved between 200 and 250 N. Up to traction forces of 250 N, the joint vacuum force counted for more than half of the total resistance. The effects of flexion and abduction on distraction of the hip were smaller. A trend for better distraction was found for 20 degrees of flexion and a significantly better distraction by avoiding abduction.
High traction forces by breakage of the joint seal can be avoided by distension using air. The passive resistance of the soft tissues increases at higher traction forces. Slight flexion without abduction showed further increase of joint distraction. Reducing the amount of traction may possibly reduce the risk of soft tissue perineal and neurologic injuries.
量化单纯牵引以及牵引与不同关节位置的空气扩张相结合的效果，以找出用最小牵引力实现髋关节充分牵张的条件。
实验性尸体研究。
对八个尸体髋关节进行研究。尸体仰卧于骨折台上，在不同关节位置进行牵引，包括有空气扩张和无空气扩张时的屈曲和外展。测量时，髋臼与股骨头之间的关节间隙由4条不同的线分隔，这些线表征髋臼的外侧缘、半月软骨的上部以及髋臼窝。
在所有测量线上，牵引与扩张相结合时髋关节的牵张明显更好。在250至300N的牵引力下，与单纯牵引相比，牵引加扩张导致关节牵张增加1.59至2.25倍。在200至250N之间实现了扩张的最大效果。在牵引力达到250N之前，关节真空力占总阻力的一半以上。屈曲和外展对髋关节牵张的影响较小。发现屈曲20度时有更好牵张的趋势，通过避免外展可实现明显更好的牵张。
通过空气扩张可避免因关节密封破裂而产生的高牵引力。在较高牵引力下软组织的被动阻力增加。轻微屈曲而不外展显示关节牵张进一步增加。减少牵引量可能会降低软组织会阴和神经损伤的风险。
