Correlations of the Laminectomy Width and C5 Palsy After Open-Door Cervical Laminoplasty.

Aim: To examine the risk factors for postoperative C5 palsy, particularly an association between the laminectomy width and C5 palsy after open-door cervical laminoplasty (CLP).

Material and methods: This single-center study analyzed data from 132 adult patients who underwent open-door CLP for degenerative diseases. C5 palsy developed in 8 (6.1%) patients, although seven of them made a full recovery. The demographic and radiographic findings of the C5 palsy group were compared with those of the non-C5 palsy group.

Results: The laminectomy width did not correlate with the incidence of C5 palsy (C5 palsy group, 19.39 ± 1.86 mm; non-C5 palsy group, 20.77 ± 2.61 mm, p > 0.05). The preoperative T2-high lesion in the spinal cord on magnetic resonance imaging was present in 62.5% of the patients in the C5 palsy group, whereas it was positive in 20.3% in the non-C5 palsy group (p = 0.021). The mean C4/5 foraminal minimal distances on the open side were 2.42 and 3.58 mm in the C5 and non-C5 palsy groups, respectively (p = 0.001). These variables might be risk factors for C5 palsy.

Conclusion: The laminectomy width was not associated with the incidence of C5 palsy. The risk factors for C5 palsy were the preoperative T2-high lesion in the spinal cord and C4/5 foraminal stenosis on the open side after open-door CLP.