Donaldson W F, Lauerman W C, Heil B, Blanc R, Swenson T
Department of Orthopaedic Surgery, University of Pittsburgh Medical Center, Pennsylvania, USA. wdonaldsuoi.upmc.edu
Spine (Phila Pa 1976). 1998 Aug 15;23(16):1729-32; discussion 1732-3. doi: 10.1097/00007632-199808150-00003.
Video fluoroscopy was used to evaluate the motion in an unstable spine during helmet and shoulder pad removal.
To observe the amount of motion that occurs during the removal of helmet and shoulder pads in an injured spine.
Removal of shoulder pads and helmet from a football player with suspected cervical spine injury can be particularly hazardous. How much flexion occurs at the unstable level during removal of equipment is unknown.
Six fresh cadavers were used in the study. In three, an unstable C1-C2 segment was created by transoral osteotomy of the base of C2. In the remaining three, instability was created at C5-C6 by a posterior release. Under fluoroscopic recording, the helmets were removed by first removing the chin strap, face mask, and ear pieces. With the neck stabilized, the helmet was carefully removed. The shoulder pads were carefully removed, with the head stabilized. Angulation, distraction, and space available for the cord were measured at C1-C2. Translation, angulation, distraction, and change in disc height were measured in the specimens with unstable C5-C6.
In cadavers with C1-C2 instability, the mean change in angulation was 5.47 degrees, and space available for the cord was 3.91 mm. Shoulder pads were removed while the head was stabilized. The mean change in angulation at C1-C2 was less during removal of shoulder pads than during helmet removal at 2.9 degrees. Space available for the cord was 2.64 mm. Distraction was also greater during helmet removal (2.98 mm) than during shoulder pad removal (1.76 mm). In the unstable spine, the change in displacement in translation was greater during shoulder pad removal (3.87 mm), than during helmet removal (0.41 mm). Disc height change was similar. Distraction of the spinous processes was greater during helmet removal (3.68 mm) than during shoulder pad removal (1.37 mm). Angulation was similar in both maneuvers.
Helmet and shoulder pad removal in the unstable cervical spine is a complex maneuver. In the unstable C1-C2 segment, helmet removal causes more angulation in flexion, more distraction, and more narrowing of the space available for the cord. In the lower cervical spine (C5-C6), helmet removal causes flexion of 9.32 degrees, and during shoulder pad removal the neck extends 8.95 degrees, a total of approximately 18 degrees. Disc height changes from 1.24 mm of distraction to 1.06 mm of compression during helmet removal and shoulder pad removal for a total 2.3-mm change. Translation, which correlates with the change in the space available for the cord, is greater at C5-C6 during shoulder pad removal. Because most of the cadavers had C5 anteriorly displaced on C6 to begin with, the extension force during shoulder pad removal caused a 3.87-mm change in reduction of C5 on C6. Because of the motion observed in the unstable spine, helmet and shoulder pad removal should be performed in a carefully monitored setting. They should be removed together by at least three, preferably four, trained people.
采用视频荧光透视法评估在摘除头盔和肩垫过程中不稳定脊柱的运动情况。
观察在受伤脊柱上摘除头盔和肩垫时发生的运动量。
从疑似颈椎损伤的橄榄球运动员身上摘除肩垫和头盔可能特别危险。在摘除装备过程中不稳定节段会发生多少屈曲尚不清楚。
本研究使用了6具新鲜尸体。其中3具，通过C2椎体基部经口截骨术制造C1-C2节段不稳定。其余3具，通过后路松解术在C5-C6节段制造不稳定。在荧光透视记录下，首先取下颏带、面罩和耳塞，然后摘除头盔。颈部保持稳定，小心地取下头盔。头部保持稳定，小心地摘除肩垫。在C1-C2节段测量成角、牵张以及脊髓可用空间。在C5-C6不稳定的标本中测量平移、成角、牵张和椎间盘高度变化。
在C1-C2不稳定的尸体中，平均成角变化为5.47度，脊髓可用空间为3.91毫米。头部保持稳定时摘除肩垫。摘除肩垫时C1-C2节段的平均成角变化（2.9度）小于摘除头盔时。脊髓可用空间为2.64毫米。摘除头盔时的牵张（2.98毫米）也大于摘除肩垫时（1.76毫米）。在不稳定脊柱中，摘除肩垫时平移位移变化（3.87毫米）大于摘除头盔时（0.41毫米）。椎间盘高度变化相似。摘除头盔时棘突间的牵张（3.68毫米）大于摘除肩垫时（1.37毫米）。两种操作中的成角相似。
在不稳定颈椎上摘除头盔和肩垫是一项复杂的操作。在不稳定的C1-C2节段，摘除头盔会导致更多的屈曲成角、更多的牵张以及脊髓可用空间更狭窄。在下颈椎（C5-C6），摘除头盔导致9.32度的屈曲，而摘除肩垫时颈部伸展8.95度，总共约18度。摘除头盔和肩垫过程中椎间盘高度从牵张1.24毫米变为压缩1.06毫米，总共变化2.3毫米。与脊髓可用空间变化相关的平移在C5-C6节段摘除肩垫时更大。由于大多数尸体最初C5相对于C6向前移位，摘除肩垫时的伸展力导致C5相对于C6复位变化3.87毫米。由于在不稳定脊柱中观察到运动，摘除头盔和肩垫应在仔细监测的环境中进行。应由至少三名，最好是四名经过培训的人员一起摘除。
