Animals were anesthetized with a combination of ketamine and xylazine (10:7,
100 mg/kg injected intraperitoneally). The coccygeal intervertebral spaces
Co6-7, Co7-8, and Co8-9 were selected for the study. The needle puncture was
performed at coccygeal intervertebral levels Co6-7 and Co8-9. The intervertebral
level Co7-8 remained undisturbed as the control level. The selected coccygeal
intervertebral levels (Co6-7 and Co8-9) were identified by digital palpation and
confirmed by fluoroscopy. After tail skin antisepsis with alcohol iodate and
using fluoroscopy, a 20-gauge needle was inserted at the level of the annulus
fibrosus of Co6-7 (proximal) and Co8-9 (distal), crossing the nucleus pulposus
up to the contralateral annulus fibrosus. After full penetration, the needle was
rotated 360° twice and held for 30 s. The depth of needle penetration was
controlled by the resistance of the contralateral annulus fibrosus.
100 mg/kg injected intraperitoneally). The coccygeal intervertebral spaces
Co6-7, Co7-8, and Co8-9 were selected for the study. The needle puncture was
performed at coccygeal intervertebral levels Co6-7 and Co8-9. The intervertebral
level Co7-8 remained undisturbed as the control level. The selected coccygeal
intervertebral levels (Co6-7 and Co8-9) were identified by digital palpation and
confirmed by fluoroscopy. After tail skin antisepsis with alcohol iodate and
using fluoroscopy, a 20-gauge needle was inserted at the level of the annulus
fibrosus of Co6-7 (proximal) and Co8-9 (distal), crossing the nucleus pulposus
up to the contralateral annulus fibrosus. After full penetration, the needle was
rotated 360° twice and held for 30 s. The depth of needle penetration was
controlled by the resistance of the contralateral annulus fibrosus.
