To compare the efficacy and safety of TDR to that of the fusion for the treatment of lumbar degenerative disc disease (LDDD).

Randomized controlled trials comparing TDR with any other intervention for LDDD were acquired by a comprehensive search in PubMedCentral, MEDLINE, EMBASE, BIOSIS, ClinicalTrials.gov, and the FDA trials register. Methodologic quality was assessed and relevant data were retrieved, and appropriate meta-analysis was performed. Two review authors independently selected studies, extracted data, and assessed risk of bias. Results and upper bounds of confidence intervals were compared with predefined clinically relevant differences.

Six relevant randomized controlled trials (RCTs) involving 1,603 patients were identified and reported two year follow-up results. Patients in TDR group compared with lumbar fusion group demonstrated significant improvements in ODI, VAS scores and complication rates at the two year follow-up. Meanwhile, except for operating time in anterior group, intra-operative blood loss, operating time in posterior group, and reoperation rate were without clinical significance between the two groups. In addition, the range of motion (ROM) was maintained within normal ranges after TDR.

The results showed the TDR has significant safety and efficacy comparable to lumbar fusion at two year follow-up. Although superiority compared to fusion could not be proved, by comparing clinical symptoms relieved, motion preserved, and the low reoperation rate during long-term follow-up on TDR, TDR was considered safe and effective. Therefore, the authors suggest adopting TDR on a large scale; with failure of TDR, interbody fusion would be performed.