Radiographic assessment in the rabbit anular puncture model of disc degeneration. An anular puncture model was established in 5-month-old New Zealand white rabbits. Under general anesthesia, lumbar intervertebral discs were exposed, and the initial puncture with an 18-gauge needle at a defined depth of puncture (5 mm) was performed on two noncontiguous discs (L2/3 and L4/5), with the disc (L3/4) between the punctured discs left intact as a control. One week after the initial puncture, either control small interfering RNA (siRNA) or ADAMTS5 siRNA oligonucleotide (10 μg in 10-μl phosphate-buffered saline (PBS) per disc) was injected into the center of the nucleus pulposus by using a 26-gauge needle. Nine weeks after the initial anular puncture (8 weeks after the injection), all rabbits were killed. Radiographs were taken at time 0 and at weeks 1, 2, 3, 5, 7, and 9 after the puncture to quantity changes in the disc-height index (DHI). The %DHI was calculated as [%DHI = (Postoperative DHI/Preoperative DHI) × 100]. At 8 weeks after the ADAMTS5 siRNA injection, no difference was found in the mean %DHI of the ADAMTS5 siRNA-injected punctured discs compared with the punctured discs that received the control siRNA injection (P > 0.05, repeated ANOVA).