Table 2. Characteristics of All Included Comparative Observational Studies.
| Studies | Study design, year published, year enrollment, intervention | Comparison group | N | Age (yr) | Gender Male (%) | Fusion level | Diagnoses (number of patients in percutaneous group, open group) | Instrumentations including cage and pedicle screw | Bone graft | Follow-up (month) |
|---|---|---|---|---|---|---|---|---|---|---|
| Parker, et al.19 | Prospective cohort study, 2014, NR, Single-level TLIF | Minimally invasive group | 50 | 53.5±12.5 | 16 (32) | L3–4; 4 | Degenerative spondylolisthesis grade I (50, 50) | A single PEEK interbody cage and percutaneous pedicle screw system (implants NR) | Local autogenous bone with or without bone extensors (i.e., DBM) | 24, % followed: NR |
| L4–5; 32 | ||||||||||
| L5–S1; 14 | ||||||||||
| Open group | 50 | 52.6±11.6 | 18 (36) | L3–4; 3 | A single PEEK interbody cage and conventional pedicle screw system (implants NR) | Local autogenous bone with or without bone extensors (i.e., DBM) | 24, % followed: NR | |||
| L4–5; 30 | ||||||||||
| L5–S1; 17 | ||||||||||
| Gu, et al.21 | Prospective cohort study, 2013, 2010–2011, Two-level TLIF | Minimally invasive group | 44 | 66.4±6.7 | 19 (43.2) | L3–5; 13 | Degenerative disc disease (15, 11) Spinal stenosis (18, 14) Spinal stenosis with segmental instability (11, 13) |
A single PEEK interbody cage (Capstone; Medtronic, Memphis, TN, USA) and percutaneous pedicle screw system (Sextant; Medtronic) | Local autologous bone | 20.6±4.5, % followed: NR |
| L4–S1; 31 | ||||||||||
| Open group | 38 | 64.1±7.8 | 15 (39.5) | L3–5; 14 | NR | NR | 20.0±3.3, % followed: NR | |||
| L4–S1; 24 | ||||||||||
| Lee, et al.22 | Prospective cohort study, 2012, 2002–2008, Single-level TLIF | Minimally invasive group | 72 | 52.2±13.8 | 20 (27.8) | L3–4; 6 | Spondylolisthesis (Grade 1 and 2) Recurrent disc herniation Spinal stenosis requiring resection of more than 50% of either facet joint |
A single PEEK interbody cage (Capstone; Medtronic) and percutaneous pedicle screw system (Sextant; Medtronic) | Local autogenous bone with DBM (Osteofil; Medtronic) | 24, 95.8% (69/72) followed for 24 months |
| L4–5; 49 | ||||||||||
| L5–S1; 17 | ||||||||||
| Open group | 72 | 56.6±14.6 | 22 (30.6) | L3–4; 4 | Degenerated collapsed disc requiring disc-space height restoration (Specific number; NR) | A single PEEK interbody cage (Capstone; Medtronic) and conventional pedicle screw system (implants NR) | Local autogenous bone with DBM (Osteofil; Medtronic) and one case with rhBMP-2 (Infuse; Medtronic) | 24, 91.7% (66/72) followed for 24 months | ||
| L4–5; 54 | ||||||||||
| L5–S1; 14 | ||||||||||
| Mobbs, et al.23 | Prospective cohort study, 2011, 2006–2010, Single- or multi-level PLIF | Minimally invasive group | 37 | 68.56±12.99 | 19 (51.4) | T11–12; 0 | Isthmic spondylolisthesis (4, 9) Degenerative spondylolisthesis (18, 9) Degenerative scoliosis (1, 4) Degenerative disc disease with foraminal stenosis (14, 8) |
A single rotatable interbody cage (implants NR) and percutaneous pedicle screw systems (Denali/ Serengeti system; K2M, Leesburg, VA, USA and MANTIS; Stryker, Kalamazoo, MI, USA) | Local autogenous bone with or without synthetic bone | 11.5 (5.4–20.1), % followed: NR |
| L2–3; 1 | ||||||||||
| L3–4; 2 | ||||||||||
| L4–5; 20 | ||||||||||
| L5–S1; 6 | ||||||||||
| Multi-level; 8 | ||||||||||
| Open group | 30 | 67.48±13.19 | 16 (53.3) | T11–12; 1 | A single rotatable interbody cage and conventional pedicle screw system (implants NR) | Local autogenous bone with or without synthetic bone | 18.7 (8.1–40.0), % followed: NR | |||
| L2–3; 0 | ||||||||||
| L3–4; 0 | ||||||||||
| L4–5; 15 | ||||||||||
| L5–S1; 9 | ||||||||||
| Multi-level; 5 | ||||||||||
| Kotani, et al.24 | Prospective cohort study, 2011, 2005–NR, Single-level PLF | Minimally invasive group | 43 | 63±9 | 14 (32.6) | L3–4; 4 | Degenerative spondylolisthesis (43, 37) | Percutaneous pedicle screw system (Sextant; Medtronic) | Autogenous posterior iliac crest bone | 32 (24–49), % followed: NR |
| Open group | 37 | 66±9 | 12 (32.4) | L4–5; 76 (no specific declaration between groups) | Conventional polyaxial pedicle screw and rod system (implants NR) | Autogenous posterior iliac crest bone | 40 (24–60), % followed: NR | |||
| Wang, et al.25 | Prospective cohort study, 2011, 2006–2008, Single- or two-level TLIF | Minimally invasive group | 25 | 54.8±10.9 | 13 (52.0) | L3–4; 2 | Recurrent disc herniation (7, 8) Postsurgical foraminal stenosis (10, 9) Postsurgical segmental instability (5, 7) Postsurgical spondylolisthesis grade 1 (3, 3) |
A single PEEK interbody cage (OIC; Stryker) and percutaneous pedicle screw system (Sextant; Medtronic) | Local autogenous bone with or without autogenous iliac crest bone | Overall, 27.5 (12–38), % followed: NR |
| L4–5; 11 | ||||||||||
| L5–S1; 9 | ||||||||||
| Two-level; 3 | ||||||||||
| Open group | 27 | 56.2±13.6 | 15 (55.6) | L3–4; 2 | A single PEEK interbody cage (OIC; Stryker) and conventional pedicle screw system (implants NR) | NR | ||||
| L4–5; 11 | ||||||||||
| L5–S1; 10 | ||||||||||
| Two-level; 4 | ||||||||||
| Wang, et al.26 | Prospective cohort study, 2010, 2006–2008, Single-level TLIF | Minimally invasive group | 42 | 47.9±8.5 | 13 (30.1) | L3–4; 3 | Degenerative spondylolisthesis (24, 22) | A single PEEK interbody cage (OIC, Stryker) and percutaneous pedicle screw system (Sextant; Medtronic) | Local autogenous bone | Overall, 26.3 (13–35), % followed: NR |
| L4–5; 21 | ||||||||||
| L5–S1; 18 | ||||||||||
| Open group | 43 | 53.2±10.6 | 16 (37.2) | L3–4; 3 | Isthmic spondylolisthesis (18, 21) | NR | NR | |||
| L4–5; 23 | ||||||||||
| L5–S1; 17 | ||||||||||
| Schizas, et al.27 | Prospective cohort study, 2008, NR, Single-level TLIF | Minimally invasive group | 18 | 45.5±NR | NR | L5–S1; 12 | Isthmic spondylolisthesis (15, 6) Degenerative disc disease with foraminal stenosis (2, 12) Iatrogenic spondylolysis (1, 0) |
A single PEEK interbody cage (Medtronic) and percutaneous pedicle screw system [Sextant (11 cases); Medtronic and Viper (7 cases); DePuy Spine, USA] | Local autologous bone with autogenous iliac crest bone | 22, % followed: NR |
| Other level (specific level;NR); 6 | ||||||||||
| Open group | 18 | 48.1±NR | NR | L5–S1; 11 | NR | Local autologous bone with autogenous iliac crest bone | 24, % followed: NR | |||
| Other level (specific level; NR); 7 | ||||||||||
| Park and Ha29 | Prospective cohort study, 2007, 2003–2004, Single-level PLIF | Minimally invasive group | 32 | 62.1±9.6 | 8 (25) | L3–4; 2 | Isthmic spondylolisthesis (6, 7) Degenerative spondylolisthesis (7, 5) Lumbar disc herniation (1, 3) |
A single PEEK interbody cage (Telamon; Medtronic) and percutaneous pedicle screw system (Sextant; Medtronic) | Local autogenous bone | 12, % followed: NR |
| L4–5; 23 | ||||||||||
| L5–S1; 7 | ||||||||||
| Open group | 29 | 59.0±12.2 | 13 (44.8) | L3–4; 3 | Spinal stenosis with segmental instability (18, 14) | A single PEEK interbody cage (Telamon; Medtronic) and conventional pedicle screw system (implants NR) | Local autogenous bone | 12, % followed: NR | ||
| L4–5; 18 | ||||||||||
| L5–S1; 8 |
TLIF, transforaminal lumbar interbody fusion; PLIF, posterior lumbar interbody fusion; PLF, posterolateral fusion; PEEK, polyetheretherketone; NR, not reported; DBM, demineralized bone matrix, and rhBMP-2, recombinant human bone morphogenetic protein-2.