Table 1.

Clinical parameters

	CWO (mean ± SD)	OWO (mean ± SD)	PWO (mean ± SD)
EBV	28 ± 4.5%	15 ± 11% (excluding outlier 99% in one case)	23 ± 15.4%
Outcome measures
ODI
Pre-op	48 ± 9.65	46.36 ± 7.89	47.4 ± 6.54
Post-opa	17.67 ± 5.58	15.64 ± 3.78	14.4 ± 3.5
VAS
Pre-op	7.08 ± 1.31	7.18 ± 1.17	7.3 ± 1.06
Post-opa	2.83 ± 0.83	2.55 ± 0.69	2.7 ± 0.67

^aPost-op recordings are from 2-year follow-up