Lumbar Disc Arthroplasty versus Fusion for Single-Level Degenerative Disc Disease: Two-Year Results from a Randomized Prospective Study

Arthrodesis of the lumbar spine is associated with lack of pain relief, loss of motion, pseudoarthrosis, sagittal balance malalignment, and adjacent segment disease. Recently, total disc replacement (TDR) has become an alternative to spinal fusion, which may prevent these complications while providing equivalent or improved outcomes. We report the single-surgeon, single-site results from a multicenter, randomized, prospective study comparing lumbar TDR with ProDisc-L with circumferential fusion. Thirty-seven patients met strict inclusion criteria. There were 5 patients in the fusion group (average age 38) and 32 patients in the ProDisc-L group (average age 41). Multiple linear regression analysis revealed that TDR significantly reduced operating times (87 versus 141 minutes, P = 0.01) and length of hospital stay (4.1 versus 5.4 days, P = 0.02). TDR subjects demonstrated equivocal overall patient satisfaction and Oswestry scores throughout 2-year follow-up. VAS scores were significantly higher in fusion patients at 18 months (P = 0.02), while TDR patients had significant improvement in SF-36 at 6 weeks following surgery compared with fusion patients (P = 0.04). TDR patients exhibited significantly increased range of motion at the operative level at 18 months following surgery (P = 0.03), whereas fusion patients demonstrated a trend toward increasing range of motion at the proximal adjacent level over time (P = 0.06). TDR patients had significantly increased anterior disc heights compared with fusion patients at 24 months (P < 0.01). Total disc replacement has emerged as a viable alternative to lumbar spinal fusion. This reflects a growing interest in motion-preservation techniques as a method to prevent adjacent segment disease and other potential complications following fusion.