LUMBAR TOTAL DISC REPLACEMENT. CLINICAL RESULTS: WITH A 2 -YEAR MINIMUM FOLLOW UP

Abstract

Objective: To assess the effectiveness of total disc replacement (TDR) (Charité SB III) for treatment of lumbar discopathy and to report the preliminary clinical results after a minimum follow-up period of two years

Materials and Methods: From 49 patients who underwent lumbar TDR, 31 patients fulfilled the criteria for clinical evaluation at least 2 years after surgery. The mean age was 39ys (range 29 – 48). Preoperative diagnosis included degenerative disc disease in 27 patients and 4 patients had post discectomy back pain. 44 disc prosthesis were implanted, 18 patients had a single level disc replacement and 13 patients had two level replacement. All patients were studied prospectively and clinical results evaluated by assessing preoperative and postoperative Oswestry Disability Index questionnaire and Visual Analogue Scale for back pain. Pre and postoperative patients’ work status as well as patient satisfaction were also assessed. The mean postoperative follow up was 3.3years (range 2 – 8 years). Statistical analysis of the results was done with the Wilcoxon Signed Ranks Test.

Results: There were significant improvements of the clinical outcome measures. Mean post operative ODI compared to mean preoperative scores of 19 and 53 respectively (p< 0.0001) and mean postoperative VAS compared to mean preoperative scores of 2.5 and 7.5 respectively (p< 0.0001). Success rates showed 51.6% of patients had an excellent result (relative improvement of ODI score, > 75%), 19.4% had a good result (relative improvement of ODI score, 60% to74%), and 29% had a fair and poor results (relative improvement of ODI score, < 60%). No major or approach related complications were encountered.

Conclusions: TDR is an effective method of treating discopathic low back pain. The medium term results are comparable to those obtained following traditional lumbar arthrodesis. Yet longer term results are still needed to comment on adjacent segment load transfer and progression of degenerative changes.