Table 2.
Characteristics of included studies
| Study | Location | Years | Study design | Diagnosis | Spinal levels | Surgery | Number of patients | Mean age (years) | NOS score | Level of evidence | |||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Obese | Nonobese | Obese | Nonobese | Combined | |||||||||
| Ain et al. [1] | USA | 1970–2003 | Retrospective | SS | L | Laminectomy | 32 | 17 | 39 | 8 | II | ||
| Andreshak et al. [2] | USA | NR | Prospective | SS, LDH | L | Laminectomy, discectomy, fusion | 55 | 95 | 47.9 | 46.8 | 5 | I | |
| Djurasovic et al. [5] | USA | 2001–2005 | Retrospective | SS, LDH | L | Fusion | 109 | 161 | 56.2 | 57.1 | 8 | II | |
| Fang et al. [6] | USA | 1991–1997 | Retrospective | SS, AIS | C, T, L | Laminectomy, discectomy, fusion | 47 | 92 | 42.5 | 5 | III | ||
| Friedman et al. [8] | USA | 1991–2001 | Prospective | DD | C, T, L | Laminectomy | 40 | 83 | 51.6 | 5 | III | ||
| Gepstein et al. [9] | Israel | 1990–2000 | Prospective | LDH | L | Laminectomy, discectomy | 67 | 231 | 69.6 | 71.9 | 8 | I | |
| Gu et al. [10] | China | 2010–2011 | Retrospective | SS | L | Fusion | 7 | 50 | 57 | 60.3 | 8 | II | |
| Gu et al. [11] | China | 1997–2000 | Retrospective | LDH | L | Discectomy | 80 | 368 | 45.4 | 7 | II | ||
| Hanigan et al. [13] | USA | 1984–1984 | Prospective | LDH | L | Discectomy | 17 | 88 | 42.7 | 40.4 | 8 | I | |
| Hardesty et al. [14] | USA | 1998–2010 | Retrospective | AIS | T, L | Fusion, segmental instrumentation | 55 | 181 | 14 | 14.5 | 8 | II | |
| Kalanithi et al.[15] | USA | 2003–2007 | Retrospective | DD | C, L | Fusion | 1455 | 83,152 | NR | NR | 8 | III | |
| Knutsson et al. [16] | Sweden | 2006–2008 | Prospective | SS | L | Fusion | 606 | 2027 | 67 | 69.4 | 8 | II | |
| Koutsoumbelis et al. [17] | USA | 2000–2006 | Retrospective | NR | L | Posterior fusion | 48 | 204 | 58.3 | 5 | III | ||
| Maragakis et al. [19] | USA | 2001–2004 | Retrospective | NR | L, S | Laminectomy, fusion | 64 | 144 | 55 | 5 | III | ||
| Mehta et al. [20] | USA | 2006–2008 | Retrospective | NR | L | Fusion | 122 | 176 | 59.7 | 5 | II | ||
| Meredith et al. [21] | USA | 2005–2008 | Retrospective | LDH | L | Microdiscectomy | 25 | 75 | 46 | 6 | II | ||
| Olsen et al. [22] | USA | 1996–1999 | Retrospective | NR | C, T, L, S | Laminectomy, fusion | 66 | 151 | 53.1 | 5 | III | ||
| Olsen et al. [23] | USA | 1998–2002 | Retrospective | DD | C, T, L, S | Laminectomy, discectomy, fusion | 92 | 181 | 52.4 | 5 | III | ||
| O’Neill et al. [24] | USA | 1991–2001 | Retrospective | AIS | T, L | Boston or custom-molded orthosis | 31 | 245 | 22.8 | 6 | II | ||
| Park et al. [25] | USA | 2006–2007 | Retrospective | SS | L | Laminectomy, discectomy, fusion | 56 | 21 | 54.1 | 43.7 | 7 | II | |
| Patel et al. [26] | USA | 2002–2005 | Retrospective | DD | T, L | Fusion | 39 | 50 | 58.8 | 6 | II | ||
| Peng et al. [27] | USA | 2007–2008 | Prospective | SS, LDH | L | Fusion | 33 | 41 | 47.3 | 44.7 | 8 | III | |
| Pull ter Gunne & Cohen [28] | USA | 1996–2005 | Retrospective | DD | C, T, L, S | Laminectomy, discectomy, fusion | 235 | 2939 | 55.6 | 5 | II | ||
| Rao et al. [30] | USA | Jan. 2008– Dec 2008 | Retrospective | DD, trauma | C, T, L | Fusion | 101 | 137 | 56 | 5 | III | ||
| Rihn et al. [31] | USA | 2000–2005 | Retrospective | DS, LSS | L | Laminectomy | 328 | 482 | 62.9 | 66.8 | 8 | II | |
| Rihn et al. [32] | USA | 2000–2005 | Retrospective | LDH | L | Discectomy | 336 | 854 | NR | NR | 8 | II | |
| Rodgers et al. [33] | USA | 2006–2008 | Retrospective | DD | T, L | Extreme lateral interbody fusion | 156 | 157 | 58.9 | 62.9 | 8 | II | |
| Rosen et al. [34] | USA | 2002–2006 | Prospective | DD | L | Fusion | 35 | 72 | 56 | 8 | I | ||
| Senker et al. [35] | Austria | 2010–2011 | Retrospective | DD | L | Fusion, laminotomy | 27 | 45 | 61.8 | 8 | II | ||
| Tomasino et al. [39] | USA | 2004–2007 | Retrospective | SS, LDH | L | Laminectomy, discectomy | 36 | 79 | 47.4 | 51.3 | 8 | II | |
| Upasani et al. [40] | USA | 1995–2004 | Retrospective | AIS | C, T, L, S | Fusion, thoracotomy | 48 | 193 | 14.3 | 8 | II | ||
| Yadla et al. [43] | USA | May 2008– Dec 2008 | Prospective | DD, trauma | T, L | Laminectomy, discectomy, fusion | 45 | 42 | 52.8 | 6 | I | ||
NOS = Newcastle-Ottawa scale; C = cervical; T: thoracic; L = lumbar; S: = sacral; DD = degenerative disease; SS = Spinal stenosis; DS = degenerative spondylolisthesis; LDH = lumbar disc herniation; AIS = adolescent idiopathic scoliosis; NR = not reported.