de Groot L, Hopkins B, Touwen B
Faculty of Human Movement Sciences, Free University, Amsterdam, The Netherlands.
Early Hum Dev. 1995 Aug 30;43(1):37-46. doi: 10.1016/0378-3782(95)01661-l.
Discrepancies between active and passive muscle power are often seen in pre-term infants over the first year. Generally of a transient nature, they are most obvious in the extensor muscles of the trunk where there is a high active muscle power relative to the passive component. While high active muscle power may not be a sign of cerebral palsy, it is our contention that it will impair functions such as unsupported sitting and the ability to rotate in this position. In this study, 20 full-term and 37 healthy pre-term infants were assessed at the (corrected) ages of 39 and 52 weeks for muscle power in the trunk, sitting unsupported and rotation around the body axis while seated. At the age of 39 weeks, all full-term infants could sit without support. In contrast half of the pre-term infants could not sit without support and the majority of them could not rotate the trunk in this position. At 52 weeks the majority of pre-term infants could sit without support, despite having higher active muscle power in the trunk. However this deviant muscle power prevented rotatory movements of the trunk during sitting. The origin of this deviance may reside in the positioning to which pre-term infants are subjected after birth and thus postural management should be directed towards avoidance of extensor positions.
在出生后的第一年，早产婴儿经常出现主动肌力量和被动肌力量之间的差异。一般来说，这种差异是暂时的，在躯干伸肌中最为明显，相对于被动成分，主动肌力量较高。虽然高主动肌力量可能不是脑瘫的迹象，但我们认为它会损害诸如无支撑坐立以及在此位置旋转的能力等功能。在这项研究中，对20名足月儿和37名健康早产儿在（矫正）39周和52周龄时进行了躯干肌肉力量、无支撑坐立以及坐位时身体轴旋转方面的评估。在39周龄时，所有足月儿都能无支撑坐立。相比之下，一半的早产儿不能无支撑坐立，并且其中大多数在这个位置不能转动躯干。在52周龄时，大多数早产儿能够无支撑坐立，尽管他们躯干的主动肌力量较高。然而，这种异常的肌肉力量妨碍了坐位时躯干的旋转运动。这种偏差的根源可能在于早产儿出生后所处的体位，因此姿势管理应旨在避免伸展体位。
