Extensor musculature of the cervical spine after laminoplasty - Morphologic evaluation by coronal view of the magnetic resonance image

Study Design. A radiographic study in 22 patients using magnetic resonance imaging was conducted. Objective. To describe the relation between postoperative cervical alignment and morphologic evaluation of the cervical extensor musculature, especially semispinalis cervics in laminoplasty. Summary of Background Data. Cervical laminoplasty has been widely accepted as a treatment for cervical myelopathy. Posterior procedures, however, involve the extensor musculature of the cervical spine. Methods. In this study, 22 patients who underwent laminoplasty for repair of the extensor musculature were reviewed prospectively. The semispinalis cervics was evaluated by coronal view of the magnetic resonance image 1 month, 12 months, and 24 months after surgery. Cervical alignment at last follow-up assessment was compared with preoperative alignment using the lateral view of cervical radiographs. Results. In 18 patients (82%), morphologic repair of semispinalis cervics had been maintained (Group A), but in 4 patients (18%), but it had not been maintained at the last follow-up assessment (Group B). Cervical alignment in Group A had been maintained, but maximum loss of cervical lordosis occurred in Group B. Moreover, Group B consisted of elderly women. Conclusions. The findings from this magnetic resonance imaging study suggest that the degree of semispinalis cervics repair affects postoperative cervical alignment, and significant loss of cervical lordosis tends to occur in elderly women who undergo laminoplasty.