Fig. 4

Results of clinical efficacy of functional scores. A Changes in VAS scores for low back pain over time. B Changes in VAS scores for lower limbs pain over time. C Changes in ODI over time. VAS visual analogue scale, ODI Oswestry disability index. a–e indicate the letter labelling of the time point difference (comparison within the group), if 2 time points have the same letter, there is no significant difference between the 2 time points (P > 0.05); otherwise, different letters at 2-time points mean the difference is significant (P ≤ 0.05)