Lee C, Woodring J H
Department of Diagnostic Radiology, University of Kentucky Medical Center, Lexington 40536-0084.
AJNR Am J Neuroradiol. 1991 Nov-Dec;12(6):1105-10.
We retrospectively reviewed the plain films and CT scans of 11 unstable atlas fractures from a series of 72 atlas fractures to better characterize these injuries and to determine if the correct diagnosis could have been made. These 11 atlas fractures were unstable because either the anterior bony ring was disrupted (six cases), the posterior longitudinal ligament was torn (one case), or both the anterior bony ring and the posterior longitudinal ligament were disrupted (four cases), allowing C1-C2 subluxation to occur. Although all the fractures were potentially unstable, only eight demonstrated subluxation on the lateral radiography. Despite the abnormal open mouth view in all cases, the plain films showed minimal abnormalities, requiring CT for definitive diagnosis. Less than half (five of 11) of the patients had other levels of spine injury or associated transverse ligament tear. Three of the 11 patients were quadriplegic, and two died as a result of their spinal cord injury. These unstable atlas fractures were similar to the classical Jefferson fracture in appearance and mechanism, except that they had fewer than four breaks in the atlas ring and were associated with severe neurologic injury and lower level spine injuries. The pattern of bilateral anterior arch fractures was associated more often with neurologic injury. Because of these differences, we chose to refer to them as Jefferson variant fractures to distinguish them from the classical Jefferson fracture and to emphasize the seriousness of this injury.
我们回顾性分析了72例寰椎骨折中的11例不稳定型寰椎骨折的X线平片和CT扫描结果，以更好地描述这些损伤，并确定是否能做出正确诊断。这11例寰椎骨折不稳定，原因是前骨环断裂（6例）、后纵韧带撕裂（1例）或前骨环和后纵韧带均断裂（4例），从而导致C1-C2半脱位。尽管所有骨折都有潜在的不稳定性，但只有8例在侧位X线片上显示半脱位。尽管所有病例的张口位片均异常，但X线平片显示的异常很轻微，需要CT才能明确诊断。不到一半（11例中的5例）的患者有其他节段的脊柱损伤或伴有横韧带撕裂。11例患者中有3例四肢瘫痪，2例因脊髓损伤死亡。这些不稳定型寰椎骨折在外观和机制上与典型的Jefferson骨折相似，只是寰椎环的骨折少于4处，且伴有严重的神经损伤和较低节段的脊柱损伤。双侧前弓骨折的模式更常与神经损伤相关。由于这些差异，我们选择将它们称为Jefferson变异型骨折，以将其与典型的Jefferson骨折区分开来，并强调这种损伤的严重性。
