Question: Preoperative diagnosis: Severe stenosis at L3-4. Postoperative diagnosis: Severe stenosis at L3-4. Procedure performed: Placed an interspinous distraction device at L3-4. Indications: This patient had neurogenic claudication relieved with flexion. Description of procedure: An incision was made centered over the L3-4 disk space. A localizing x-ray was obtained. We carried the incision down through the fascia and then put in a self-retaining retractor. We then found the interspinous ligament and put a couple dilators through that, measured for a distraction device of 12, put in the interspinous distraction device. After putting in a 12 trial then put over the distraction device, the plates to compress on to the spinous processes. This had good fit. We then used the locking device to lock the device in. We then thoroughly irrigated the wound, closed the wound in layers with 0 Vicryl, 2-0 Vicryl, and 4-0 Monocryl closure. Dry sterile dressing was applied to the wound. Answer: You should report Category III code 0171T (Insertion of posterior spinous process distraction device [including necessary removal of bone or ligament for insertion and imaging guidance] lumbar; single level) for this procedure.