Three- to six-year follow-up of stand-alone BAK cages implanted by a single surgeon.

ABSTRACT

BACKGROUND CONTEXT Multiple studies involving the outcomes of anterior interbody cages have been published, but the majority were by authors who designed the cage. No outcome studies with Bagby and Kuslich (BAK) cages implanted by a single-surgeon have either 3 years of follow-up or at least 25 patients. PURPOSE: To determine the 3- to 6-year clinical outcomes, including fusion rate, revision rate, complications and functional status of patients who underwent placement of anterior, stand-alone BAK cages by a single surgeon. STUDY DESIGN: This is a retrospective cohort study of patients who underwent anterior, stand-alone BAK cage placement by a single surgeon with a minimum of 3 years of follow-up. PATIENT SAMPLE A total of 46 consecutive patients who underwent placement of anterior BAK cages from 1997 to 1999 were the study group. OUTCOME MEASURES: Complications, fusion rate, revision rate, Prolo scores, Oswestry scores, pain scores, patient satisfaction. METHODS: A retrospective review of charts of patients undergoing anterior stand-alone placement of BAK cages over the study period were reviewed. Demographic data were collected, and postoperative radiographs and clinic notes were reviewed. Patients were then contacted to complete a survey to determine Prolo and Oswestry scores, workers' compensation status and general satisfaction with the procedure. Patients were also asked to undergo repeat radiographs of their lumbar spine to determine if the operative levels had fused. RESULTS: Follow-up was available on 33 of 46 patients (72%). At least 10 patients (22%) required revision surgery. Ten patients (22%) had 14 total complications not requiring revision surgery. Seventy percent of patients had a fair or poor outcome as assessed by the Prolo rating system, and 58% of patients had at least "severe disability" according to the Oswestry outcome scale. Fifty percent of patients were satisfied with their surgery. CONCLUSIONS: This single-surgeon series of stand-alone BAK cages demonstrates significantly worse clinical outcomes than has been previously reported. The use of stand-alone BAK cages for degenerative disc disease should be reconsidered given the large number of patients with unacceptable outcomes.