An In Vitro Biomechanical Study of the Ectopic Functional Reconstruction of the Transverse Ligament of Atlas.

OBJECTIVE

To evaluate the stability and function of the C1-C2 joint after ectopic functional reconstruction (EFR) of the C1 transverse ligament.

METHODS

Eight human cadaveric cervical spines (C0-C4) were subjected to in vitro biomechanical test with moment control. Spine specimens were tested under the following conditions: 1) left intact; 2) destabilized by severing the transverse ligament of atlas; 3) after EFR of the transverse ligament. Range of motion was measured in flexion, extension, lateral bending, and axial rotation.

RESULTS

Destabilization significantly increased range of motion in all directions compared with the intact status (P < 0.001). However, after EFR of the transverse ligament, range of motion in all directions was restored to the intact state. Meanwhile, coupling motions were reproduced in the axial rotation.

CONCLUSIONS

EFR of the transverse ligament virtually recovers all the physiological functions of the native transverse ligament and might be a promising alternative for the treatment of anterior atlantoaxial dislocation. Further studies are warranted before clinical application of EFR of the transverse ligament.