Cranial kyphotic change after multilevel anterior cervical corpectomy and fusion may lead to myelopathy recurrence.

OBJECTIVE: We aimed to determine the characteristic alignment change in patients with myelopathy recurrence after multilevel anterior cervical corpectomy and fusion (m-ACCF). METHODS: Fifty-two patients who underwent m-ACCF, including 20 who underwent revision surgeries for myelopathy recurrence (R-group) and 32 postoperative asymptomatic patients (A-group), were analyzed. Classic alignment parameters (cervical lordosis angle [CL], cervical sagittal vertical axis, and fusion area angle and length) and original alignment parameters (alpha-beta, beta-BG, BG-gamma, and gamma-delta angles) were measured preoperatively, postoperatively, and at follow-up or before revision surgery. The difference in the amount of change in parameters between the groups was analyzed. The relationship between the distribution of restenotic lesions and characteristic alignment change in the R-group was evaluated. RESULTS: The CL, fusion area angle, and fusion area length in the R-group significantly decreased postoperatively compared with those in the A-group (p<0.01, p<0.01, p=0.04, respectively). Compared with those in the A-group, alpha-beta and beta-BG angles in the R-group significantly decreased (p<0.01), indicating kyphotic change on the cranial side. BG-gamma and gamma-delta angles in the R-group significantly increased (p<0.01), indicating lordotic change in the caudal fused area. Restenotic lesions significantly increased on the cranial side in the R-group (cranial side, 19 levels; caudal side, 5 levels; p<0.01). CONCLUSIONS: In patients with myelopathy recurrence after m-ACCF, the cranial side has significant kyphosis and the caudal side has lordosis. Moreover, 79.2% of the restenotic lesions were significantly maldistributed on the cranial side. Surgeons should pay close attention to cranial kyphosis inducing myelopathy recurrence after m-ACCF.