BACKGROUND Treatment of severe rigid 360 degrees fused cervical kyphosis (CK) is challenging and often requires a combined approach for ankylosis release, establishment of sagittal balance, and fixation with fusion. OBSERVATIONS Four patients with iatrogenic 360 degrees fused severe rigid CK (Cobb angle >= 40 degrees) were enrolled for this retrospective analysis. All patients in the case series were female, with an average age of 27 years. All patients previously underwent posterior laminectomy/laminoplasty and cervical tumor resection when they were children (13-17 years). They underwent correction surgery with a 540 degrees posterior-anterior-posterior approach. Preoperative and final follow-up radiography and computed tomography (CT) were used to evaluate kyphosis correction, internal fixation implants, and bone fusion. The preoperative and final follow-up average C2-7 Cobb angles were -32.4 degrees +/- 12.0 degrees and 5.3 degrees +/- 7.1 degrees, respectively. Preoperative and final follow-up CK angles averaged -47.2 degrees +/- 7.4 degrees and -0.9 degrees +/- 16.1 degrees, respectively. The mean correction angle was 46.3 degrees +/- 9.6 degrees. At final follow-up, CT showed stable fixation and solid bone fusion. LESSONS The rare iatrogenic severe kyphosis with 360 degrees ankylosis requires a combined approach. The 540 degrees posterior-anterior-posterior approach can completely release the bony fusion, and the CK can be corrected using an anterior plate. This technique can achieve good results and is an effective strategy.