The patient came to the clinic 20-July-2010 complaining of LBP with bilateral sciatica for 3 years. The last 18 months got exacerbation of the right sciatica with dysesthesia of both feet.

MRI lumbar spine performed 17-July-2010 showing spondylolisthesis L4-5 Meyerding grade II with secondary canal stenosis. Dynamic studies showed considerable shift of the L4 over the L5 upon flexion and extension.

On examination: the patient had exaggerated scoliotic stance, not limping, weak dorsiflexion left foot 4/5 and right foot 3/5 and planterflexion right foot -4/5.

In the prone position, decompressive laminectomy of L4 and partial of L5 was done. Foraminotomy of right L5 was achieved. Using image-intensifier transpedicular screws Zimmer Java version were applied under the control of neurophysiological control Inomed HighLine with transpedicular set. It was interesting that the direct stimulation of the left sided root were responding to 1.8 mA with DNS 0.2 msec duration. The left exposed L4 root was responding only to 5 mA current.  The probes and the pedicle screws did not show any response even to 15 mA current. There was only local contraction of the surrounding paraspinal muscles, but the EMG records of the tibialis anterior and gastrocnemius muscles did not show any response, which means that the screws are away from the root and no irritating cracks near the root.

Discectomy of L4-5 was achieved from the right. Meticulous cleaning of the disc space was done. TILF cage 7X5 was inserted to the center of the disc cavity.

Fusion with compression was applied between L4 and L5 bodies. The bone harvested from the spinous processes and acceptable bone from the lateral masses was used and inserted before and after the introduction of the TILF.  The milled bone also was aided lateral to the rods and a bridge was added to obtain maximal security of the device.

Smooth postoperative recovery and improvement of the power of both feet.

This case demonstrate the need for electrophysiological control during insertion of the transpedicular screws.

Insertion of TILF can bring some reduction of the slipped construct and minimize possible compression upon the root. Future fusion of L4-5 will follow, which is welcome consequence to such surgery.

The right running root were responding only to 6 mA of stimulation, which conform with the clinical data in comparison to the left side were root were responding to a current of 1.8 mA.