Comparison of biportal endoscopic vs minimally invasive transforaminal lumbar interbody fusion for single-level low-grade lumbar spondylolisthesis: A retrospective cohort study

Table 4 Radiological parameters, n (%)/mean ± SD

Variable	BE-TLIF (n = 32)	MI-TLIF (n = 31)	MD/RD 95%CI	Group × time interaction
DH (mm)				F = 0.58, P = 0.630
Preoperative	9.06 ± 0.78	8.86 ± 0.54	0.20 (-0.21 to 0.61)
Postoperative 3 months	10.33 ± 0.67	10.60 ± 0.56	-0.27 (-0.61 to 0.07)
Postoperative 12 months	10.35 ± 0.68	10.62 ± 0.63	-0.27 (-0.62 to 0.08)
Final follow-up	10.40 ± 0.60	10.62 ± 0.58	-0.22 (-0.54 to 0.10)
LL (°)				F = 0.45, P = 0.718
Preoperative	31.31 ± 0.61	31.15 ± 0.58	0.16 (-0.21 to 0.53)
Postoperative 3 months	32.04 ± 0.55	31.92 ± 0.52	0.12 (-0.20 to 0.44)
Postoperative 12 months	34.00 ± 0.49	34.14 ± 0.59	-0.14 (-0.38 to 0.10)
Final follow-up	33.89 ± 0.53	33.95 ± 0.54	-0.06 (-0.28 to 0.16)
SLA (°)				F = 0.21, P = 0.889
Preoperative	9.49 ± 1.12	9.76 ± 1.11	-0.27 (-0.84 to 0.30)
Postoperative 3 months	11.65 ± 0.90	11.49 ± 0.95	0.16 (-0.31 to 0.63)
Postoperative 12 months	11.88 ± 0.62	11.92 ± 0.59	-0.04 (-0.29 to 0.21)
Final follow-up	11.63 ± 0.74	11.68 ± 0.82	-0.05 (-0.39 to 0.29)
SP (%)				F = 0.36, P = 0.782
Preoperative	17.65 ± 3.70	18.59 ± 4.33	-0.94 (-3.42 to 1.54)
Postoperative 3 months	3.42 ± 1.12	3.62 ± 1.44	-0.20 (-0.92 to 0.52)
Postoperative 12 months	3.59 ± 0.71	3.70 ± 1.06	-0.11 (-0.51 to 0.29)
Final follow-up	3.66 ± 0.77	3.74 ± 0.97	-0.08 (-0.44 to 0.28)
FR (%)	29 (90.6)	28 (90.3)	0.3 (-14.2 to 14.8)	P = 0.9791

¹Fisher’s exact test.

DH: Disc height; LL: Lumbar lordosis; SLA: Segmental lordosis angle; SP: Slip percentage; FR: Fusion rate; MD: Mean difference; RD: Risk difference; BE-TLIF: Biportal endoscopic transforaminal lumbar interbody fusion; MI-TLIF: Minimally invasive transforaminal lumbar interbody fusion.