Table 1.

Follow-up data in months regarding minimum follow-up, mean follow-up, and range in months of follow-up

Author	Min follow-up (mo)	Mean follow-up (mo)	Range (mo)
Hsieh et al. [22] (2017)	12	22.36	12–37
Mobbs et al. [4] (2016)	10	15	NA
Lee et al. [23] (2015)	12	NA	NA
Pinson et al. [24] (2017)	36	NA	NA
De Kunder et al. [20] (2017)	2	NA	2–12
Hayashi et al. [25] (2016)	24	40.45	24–74
Rothenfluh et al. [17] (2014)	NA	NA	NA
Kim et al. [26] (2010)	24	NA	NA
Okuda et al. [27] (2014)	24	96	24–204
Gologorsky et al. [28] (2014)	37	52	37–63
Sakaura et al. [29] (2016)	24	35.4	25–41
Dorward et al. [3] (2013)	24	33 (TLIF), 52 (ALIF)	NA
Makino et al. [18] (2017)	24	24	NA
Fleege et al. [30] (2016)	NA	94.8 (ALIF), 67.2 (PLIF)	NA
Baeesa et al. [31] (2016)	NA	219	243–267
Lara-Almunia et al. [21] (2015)	12	NA	NA
Malham et al. [32] (2016)	NA	34.1	24–60
Audat et al. [6] (2012)	3	NA	3–36
Hosono et al. [33] (2008)	12	75.8	12–110
Min et al. [34] (2007)	24	44.6	24–68
Quraishi et al. [35] (2013)	NA	NA	NA
Rao et al. [36] (2015)	NA	20	12–42
Li et al. [37] (2017)	NA	4.3	2–7
Jang et al. [19] (2015)	3	NA	NA
Mean of all	19	53.9	2–267

NA, not available; TLIF, transforaminal lumbar interbody fusion; ALIF, anterior lumbar interbody fusion; PLIF, posterior lumbar interbody fusion.