寰椎横韧带断裂对枕颈部稳定性的影响

A biomechanical study of occipital-atlanto-axial complex after transverse ligament rupture

寰椎横韧带损伤可导致枕颈部不稳定而产生高位颈髓压迫症。为比较寰椎横韧带损伤对寰枕关节（Ｃ０～Ｃ１）和寰枢关节（Ｃ１～Ｃ２）三维运动范围的影响，本实验对６具新鲜人尸的枕颈部骨韧带标本（Ｃ０～Ｃ３），切断两侧寰椎横韧带，测定Ｃ０～Ｃ１和Ｃ１～Ｃ２的三维运动范围。结果表明：寰椎横韧带在两侧断裂后，对Ｃ０～Ｃ１的影响主要表现为平均侧屈运动范围增大，由正常的７．０９°增至损伤后的１０．１２°，而对伸、屈及旋转运动的影响很小。对Ｃ１～Ｃ２的影响则表现为前屈、侧屈及旋转运动范围显著增大，分别由正常的２０．２５°，８．１７°和４７．８６°增至４０．９１°、１６．０５°和５９．６７°。实验结果提示，寰椎横韧带断裂主要导致Ｃ１～Ｃ２不稳定，特别是前屈运动范围显著增加。因此，寰椎横韧带损伤后，治疗的重点是恢复Ｃ１～Ｃ２的稳定性。

Rupture of transverse ligament of atlas will cause C0-C1-C2-complex instability which will result in acute or chronic high cervical spinal cord myelopathy.In order to demonstrate the range of motion (ROM) of C0～C1 and C1￣C2 after rupture of transverse ligament,six fresh cadaver specimens of C0～C3 were studied.Rilateral transverse ligament rupture was reproduced by surgical operation,and ROM of C0～C1 and C1～C2 was measured quantitatively by biomechanical method.The result indicated that the effect of the transverse ligament rupture on C0～C1 ROM was increase of average lateral bending, from 7. 09°normal to 10. 12° and the effect on ROM of flexion-extension and rotation was little. The effect of transverse ligament rupture on C1～C2 ROM was significant increase of flexion, lateral bending and rotation from 20.25°,8.17° and 47.86° normal to 40.gl°,16.05°,and 59. 67°.There is a significant difference between nomal and transverse ligament rupture ROM in flexion,lateral bending and rotation at C1～C2(P<0.05).The results suggest that the rupture of transverse ligament resulted in an instability of the C1～C2 ,specially an increased ROM of flexion.Therefore,treatment of instability of the C0-C1-C2-complex which result in rupture of transverse ligament should be concerned with increasing the stability of C1￣C2 joint.