Table 2. The early follow-up Fisher’s exact test: this result is significant with P=0.013.

ZCQ score	tcMEP better	tcMEP unchanged	Total
ZCQ improved	6	1	7
ZCQ unchanged	2	9	11
Total	8	10	18

ZCQ, Zurich Claudication Questionnaire; tcMEP, trans-cranial motor evoked potential.