Abstract
Introduction
The majority of spine patients present with discogenic low back pain, originating from either degenerative disc disease (DDD) or internal disc disruption (IDD). Successful treatment of this patient population relies on obtaining precision diagnosis and careful patient selection, as well as matching the pathology with reliable technology. Total disc replacement (TDR), as an alternative to spinal fusion in the treatment of DDD or IDD, has been studied and reported for several decades in long-term follow-up studies and in several randomized control trials. This prospective study presents a single surgeon experience with two-level CHARITÉ® TDR in 84 consecutive patients, with minimum follow-up of 5 years. The aims of the study were to assess the clinical outcomes of two-level TDR in patients with DDD/IDD. Based on the literature review conducted, this study is considered the largest single surgeon series experience with the two-level CHARITÉ® TDR in the treatment of lumbar DDD, with a minimum follow-up of 5 years reported to date.
Materials and Methods
Between January 1997 and March 2006, n=84 consecutive patients underwent two-level TDR for the treatment of two-level DDD or IDD discogenic axial low back pain with or without radicular pain. All patients completed self-assessment outcome questionnaires pre and postoperatively (3, 6, 12 months, and yearly thereafter), including Oswestry Disability Index (ODI), Roland-Morris Disability Questionnaire (RMDQ) and Visual Analogue Score (VAS) for back and leg pain.
Results
For the n=84 patients, the mean follow-up was 94.34±2.19 months (range = 62–150). The mean age was 49.6±0.94. The mean surgical time was 91±3.16 minutes and the mean blood loss was 207.5±30.62 mls. The main diagnosis was two-level DDD in 63 (76.8%) patients, followed by one-level disc herniation and one-level DDD. Seventy-three (89%) patients underwent L4-5 L5-S1 TDR and 9 (11%) patients underwent L3-4 L4-5 TDR. At all follow-up points, patients demonstrated significant improvement in ODI, RMDQ, and VAS back and leg pain scores compared to pre-operative scores (p < 0.001). The mean improvement between pre-op and last follow-up was 33.3 (66.8%) and 13.23 (74%) for ODI and RMDQ, respectively. Similarly, that was 54.8 (69 %%) and 34.8 (65%) for VAS back and VAS leg pain, respectively. At least 87.8% of the patients rated their satisfaction as good/excellent at any follow-up point. At 5 years follow-up, 54 patients (65.9%) rated their satisfaction as excellent, 19 (23.2%) as good, 7 (8.5%) as satisfactory and 2 (2.4%) as poor. Two patients (2 out of 84, 2.38%) required early revision of one of the prostheses due to failure of indication and/or failure of technique. There has been no device failure. One patient required surgery for adjacent segment disease (1.19%).
Conclusion
This study has shown that statistically significant reductions in pain and functional outcomes can be obtained in patients at a minimum follow-up of 5-years following 2-level TDR for the treatment of multilevel DDD or IDD. The clinical benefits of this procedure is supported by the data, with the outcomes reflecting a precision diagnosis, stringent patient selection criteria, and a standardised surgical technique.
