Indication of C2-C7 Cervical Laminoplasty with Muscle and Ligament Preservation in Patients with Kyphosis

Abstract

Cervical laminoplasty is generally not indicated in patients with kyphosis because of poor outcomes. Therefore, data on the effectiveness of posterior structure-preserving techniques in patients with kyphosis are limited. This study investigated how laminoplasty with muscle and ligament preservation can benefit patients with kyphosis via risk factor analyses of postoperative complications. Clinicoradiological outcomes of 106 consecutive patients, including patients with kyphosis, who had undergone C2-C7 laminoplasty in a muscle- and ligament-preserving fashion, were retrospectively analyzed. Surgical outcomes, including neurological recovery, were assessed, and sagittal parameters were measured on radiographs. Surgical outcomes of patients with kyphosis were comparable to outcomes of other patients except for axial pain (AP), which was significantly more frequent in patients with kyphosis. Moreover, AP was significantly associated with alignment loss (AL) >0°. Substantial local kyphosis (local kyphosis angle >10°) and greater value of range of motion (ROM) during flexion minus ROM during extension were identified as risk factors for AP and AL >0°, respectively. Receiver operating characteristic curve analysis indicated ROM during flexion minus ROM during extension cutoff value of 0.7° for predicting AL >0° in patients with kyphosis (sensitivity: 77%; specificity: 84%). Substantial local kyphosis combined with ROM during flexion minus ROM during extension >0.7° had 56% sensitivity and 84% specificity for predicting AP in patients with kyphosis. Although patients with kyphosis had a significantly higher incidence of AP, C2-C7 cervical laminoplasty with muscle and ligament preservation may not be contraindicated in selected patients with kyphosis by risk stratification for AP and AL using newly identified risk factors.