I took this from CPT Assistant (January 2000)
You may bill a 62310 (Cervical) and 62310-59 (Thoracic).
"CPT codes 62310-62319 are procedures. These codes are reported once per level, per side, regardless of the number or type of injections performed per level, per side. Therefore, it is inappropriate to report the spinal injection code(s) for each injection performed at a particular level and side. However, if both sides of the same spinal level are injected, then modifier -50 should be appended to the specific injection procedure code to indicate that bilateral procedures were performed. If injections are performed at different spinal levels (eg, C2 and C4), then the spinal injection codes are reported for each level of the spinal region involved."
Hope this helps.