The patient came to the clinic 12-May-2007 in wheelchair complaining of complete paraplegia below L1 level with loss of micturition and defecation control. The patient underwent surgery for PLD L4-5 1996 for left sciatica. The patient then was operated 20-February-2007 for the "recurrence".

On examination: the patient had profound weak both quadriceps muscles 1/5, abduction and adduction of the knees 0/5 and the dorsi and planterflexion both feet is 0/5. She has no sensation for micturition and defecation.

MRI lumbar spine performed 25-April-2007 showing severe stenosis L1-2 with extruded disc obliterating the space more from the left, with spondylolisthesis L4-5 due to absence of the isthmi of L4-5 both sides.

Decompressive laminectomy of L1 and L2 was performed, using drilling to prevent surgical trauma to the spinal cord. The isthmi are very close to the midline. Considering that, foraminotomy of left L2 root was performed without violating the stability of the region. The extruded disc was removed from the left side lateral to the axilla. Meticulous cleaning of the disc space of L1-2 disc space from the left.
Under the image intensifier the remnants of the L4 and L5 were identified and transpedicular screw fixation with reduction and distraction was performed between L4 and L5 bodies. Bone graft was inserted between the lateral processii of L4 and L5. Routine closure of the wound.

Smooth postoperative recovery.

The patient showed mild improvement of the quadriceps and abduction and adduction of the knees immediately after the operation and start to feel pain in the right lower limb.

Removal of the isthmi could cause segmental instability, as in this case. The patient was not complaining about this instability, because, she was paraplegic below L1 level. This problem will show up in case of improvement of the neurological status after surgery. So as to avoid this future situation, transpedicular screw fixation and reduction was performed.

Careful neurologic evaluation, must be performed to avoid mistakes in decision making and planning for surgery. The patients main problem was at the level of L1-2. Despite this fact, the patient was sent to perform MRI of the dorsal spine, so as not perform another mistake.