Treatment Outcome of Transforaminal Lumbar Interbody Fusion (TLIF) Using Unilateral Pedicle Screw Fixation for Lumbar Foraminal Stenosis

Abstract

Transforaminal lumbar interbody fusion (TLIF) for both anterior/posterior and superior/inferior decompression of foramina can be indicated. The purpose of this study was to examine the outcome of unilateral TLIF and pedicle screw (PS) fixation for lumbar foraminal stenosis. The subjects were 24 consecutive patients who underwent monosegmental fusion for lumbar foraminal stenosis; there were 14 men and 10 women. All subjects underwent fusion at L5-S for unilateral L5 radiculopathy. A titanium cage was used in 10 subjects (titanium group) and a carbon or polyetheretherketone (PEEK) cage was used in 14 subjects (carbon/PEEK group). Clinical conditions and radiological findings were examined pre- and postoperatively, and at the final follow-up. The mean Roland and Morris Disability index improved from 8.5 preoperatively to 3.8 points. Excellent and good patient satisfaction was obtained in 2/3 of the patients. The mean disc height was increased by 2.0mm immediately after surgery and by 1.1mm at the final follow-up compared with the height before surgery. Subsidence of the cage of more than 3.0mm was observed in 60% patients of the titanium group and in 14% patients of the carbon/PEEK group (P<0.05). Unilateral TLIF and PS fixation was demonstrated to be less invasive for paravertebral muscles with a lower incidence of adjacent lumbar foraminal stenosis, resulting in a good outcome. Although there was no significant difference in clinical outcomes, subsidence of the cage was 4-fold higher in the titanium cage group than in patients receiving the carbon/PEEK cages. These findings indicate that unilateral TLIF and PS fixation are useful procedures.