Table 2. Frequency distribution of foraminoplasty levels.

Variable	Frequency	Percent	Valid percent	Cumulative percent
SED foraminoplasty L4/5	67	38.1	38.1	38.1
SED foraminoplasty L5/S1	31	17.6	17.6	55.7
SED foraminoplasty L4–S1	25	14.2	14.2	69.9
SED foraminoplasty L3/4	8	4.5	4.5	74.4
SED foraminoplasty L4–S1 rhizotomy	8	4.5	4.5	79.0
SED foraminoplasty L5/S1 rhizotomy	8	4.5	4.5	83.5
SED foraminoplasty L4/5 rhizotomy	7	4.0	4.0	87.5
SED foraminoplasty L2/3	4	2.3	2.3	89.8
SED foraminoplasty L3–L5	4	2.3	2.3	92.0
SED foraminoplasty L3/4 rhizotomy	3	1.7	1.7	93.8
SED foraminoplasty L2–L4 rhizotomy	2	1.1	1.1	94.9
SED foraminoplasty L2/3 rhizotomy	2	1.1	1.1	96.0
SED foraminoplasty L3–5	2	1.1	1.1	97.2
SED foraminoplasty L3–L5 rhizotomy	2	1.1	1.1	98.3
SED foraminoplasty L2–L4	1	0.6	0.6	98.9
SED foraminoplasty L3–S1	1	0.6	0.6	99.4
SED foraminoplasty L3/4 and L5/S1	1	0.6	0.6	100.0
Total	176	100.0	100.0

SED, selective endoscopic discectomy.