| Malmivaara, et al. (18), 2007 |
50 |
Multicenter randomized controlled trial assessing conservative management versus single- and multi-level decompression and transpedicular fusion with 2-year follow-up |
Patients in both groups improved, but the surgical intervention group had greater reductions in pain and disability |
| Kim, et al. (19), 2010 |
128 |
Single-center retrospective study of four patient cohorts undergoing mini-anterior lumbar interbody fusion (ALIF, 86), or mini-transforaminal lumbar interbody fusion (TLIF, 42) procedures at two levels with PEEK cages and >2-year follow-up |
Significant improvements were seen in all cohorts with no differences in pain or disability |
| Sys, et al. (20), 2011 |
38 |
Single-center prospective randomized controlled trial assessing the clinical effectiveness of using platelet-rich plasma (PRP) and iliac crest bone (ICB) chips with carbon-fiber reinforced PEEK cages (CFRP) versus the same materials excluding the use of PRP for 2-year follow-up |
Addition of PRP in posterior lumbar interbody fusion did not lead to a substantial improvement or deterioration when compared with autologous bone only |
| Nemoto, et al. (21), 2014 |
48 |
Retrospective review of prospectively collected data at a single center comparing 23 and 25 single-level TLIF cases using either Ti or PEEK cages, respectively, with 2-year follow-up |
The superiority of PEEK over Ti was not demonstrated. There were unfavorable radiographic findings for PEEK associated with nonunion |
| Buttermann, et al. (22), 2015 |
50 |
Single-center prospective randomized controlled and blinded trial comparing midline and paraspinal approaches for two-level fusion using allograft cortical rings and ICB with >5 years follow-up |
Midline and paraspinal approaches resulted in similar outcomes for two-level spinal fusion |
| Fei, et al. (23), 2015 |
176 |
Single-center prospective study assessing clinical outcomes for single- and multilevel degenerative disc disease treated using either posterior dynamic stabilization (PDS) with polycarbonate urethane spacers or posterior lumbar intervertebral fusion (PLIF) with an unspecified cage and autologous bone graft and 3-year follow-up |
Compared with PLIF, PDS had advantages for blood loss, length of hospital stays, radiographic outcomes, and total cost; but there were no statistically significant differences in back or leg VAS pain or Oswestry disability index (ODI) scores |
| Lattig, et al. (24), 2015 |
89 |
Single-center retrospective study examining clinical outcomes for single-level decompression alone or decompression with fusion (D&F) where facet effusion was a sign of degenerative spondylolisthesis for 2-year follow-up. Only D&F cases with or without effusion were included in this analysis. The fusion method and spacer or cage was not specified |
There were no significant differences in outcomes based on the presence or absence of facet effusion or surgical treatment. The effusion sign alone is not an indication for adding fusion to decompression in the treatment of lumbar degenerative spondylolisthesis. |
| Siepe, et al. (25), 2015 |
71 |
Single-center prospective study assessing mid-term (35.1 months) follow-up for a single-level stand-alone PEEK/Ti intervertebral lumbar spinal fusion cage |
Overall, there was a significant improvement from baseline VAS and ODI scores and 77.5% of patients reported highly satisfactory outcomes |
| Försth, et al. (26), 2016 |
111 |
Multicenter randomized controlled trial assessing clinical effectiveness for single- and two-level decompression or decompression with fusion surgery for patients with lumbar spinal stenosis at 2- and 5-year follow-up. Only D&F cases were included in this analysis. The D&F method and spacer or cage materials were not specified. They were determined solely by the surgeon |
Decompression and fusion surgery did not result in improved clinical outcomes at 2- and 5-year compared to decompression surgery alone |
| Hoff, et al. (27), 2016 |
24 |
Single-center prospective randomized controlled trial assessing two-level hybrid stand-alone ALIF at L5/S1 with total disc replacement (TDR) at L4/L5 as an alternative to two-level circumferential TLIF at L4-S1 using a PEEK cage at 37 months follow-up. Only the TLIF data are included in this analysis |
Both cohorts demonstrated significant clinical improvement at the final follow-up compared to their preoperative conditions. However, pain scores for hybrid cases were significantly lower at the final follow-up than the TLIF patients |
| Kim, et al. (28), 2016 |
50 |
Multicenter retrospective review of prospectively acquired patient data assessing the clinical effectiveness of an expandable TLIF PEEK/Ti composite cage at ≥12 months follow-up |
The expandable interbody cage led to significant improvement in clinical and radiographic outcomes, including disc height restoration, fusion, and minimal device-related complications |
| Lee, et al. (29), 2016 |
74 |
Multicenter prospective randomized single-blinded controlled study evaluating the clinical effectiveness of a single-level PLIF using either a CaO-SiO2-P2O5-B2O3 bioactive glass ceramic spacer or a traditional Ti cage for 1-year follow-up |
Patients receiving the bioactive glass ceramic spacer or the Ti cage had similar fusion rates and clinical outcomes. There were no significant differences between the cohorts |
| Rickert, et al. (30), 2017 |
38 |
Single-center prospective randomized clinical pilot trial comparing clinical and radiological outcomes for one and two level TLIF using a PEEK cage with and without a Ti-coating at 12 months follow-up |
Identical outcomes with high rates of fusion were seen in both groups. The Ti-coating appeared to have no safety or efficacy issues at 12 months follow-up |
| Kim, et al. (31), 2018 |
78 |
Single-center prospective, randomized, controlled trial comparing robot-assisted versus free-hand PLIF with an unspecified interbody cage for ≥1-year follow-up |
Clinical outcomes including VAS and ODI scores did not differ between the two cohorts |
