Objective: To assess the effect of modified cervical expansive open-door laminoplasty preserving the posterior extensor musculature inserted into the C2 and C7 spinous process upon maintaining the cervical lordotic alignment and axial syndrome and to determine whether preserving the posterior extensor musculature inserted into C2 and C7 spinous process can reduce the complications.
Methods: Twenty-eight patients undergoing modified cervical expansive open-door laminoplasty preserving the posterior extensor musculature inserted into the C2 and C7 spinous process and 21 patients undergoing conventional C3-C7 cervical expansive open-door laminoplasty were investigated in pre-operative, post-operative and 3-month follow-up. The investigators assessed the effects of two different cervical laminoplasty types in the recovery rate of JOA score, the changes of Cobb angle and Ishihara's index, axial syndrome, operating duration and intra-operative blood loss, analyzed the results in SPSS and tried to find the difference in two operative types.
Results: There were the same results in the recovery rate of JOA score and intra-operative blood loss in modified expansive open-door cervical laminoplasty group and the conventional C3-C7 cervical expansive open-door laminoplasty group. The smaller changes of Cobb angle and Ishihara's index in the follow-up of modified laminoplasty group were found. The modified laminoplasty group had fewer patients suffering the axial syndrome in follow-up. The operating duration was shorter in the modified laminoplasty group.
Conclusion: Preventing muscle injuries in cervical laminoplasty can reduce the incidence of complications. The modified expansive open-door cervical laminoplasty preserving the posterior extensor musculature inserted into C2 and C7 spinous process can protect cervical posterior extensor musculature. This is helpful to maintain the cervical lordotic alignment and reduce the incidence of post-operative axial syndrome.