Preliminary Followup of Impacted Posterior Lumbar lnterbody Fusion (PLIF)

Thomas T Lee, MD
Kevin T Foley MD
Ramesh Sahjpaul MD

Objective:

Posterior lumbar interbody fusion (PLIF)has been used for the surgical treatment of spondylolisthesis, instability, and degenerative disc disease. The authors review a series of patients treated with impacted PLIF'S.

Material and Method:

Thirty–three consecutive patients with intractable pain syndrome from isthmic or degenerative spondylolisthesis, post– operative instability, recurrent herniated discs, or degenerative disc disease were treated with impacted PLIF'S. Two cortical allografts and vertebral autograft were utilized as the interbody implants. Pedicle screw fixation was performed to provide immediate stability. Forty levels of impacted PLIF's were performed in 33 patients. The mean followup was 10.5 months. Plain radiographs were obtained at one, three, and six months, then as needed.

Results:

No neurological or infectious complication was noted. The mean hospital stay was 3.24 days. All 33 patients had significantly reduced lower back pain. 24 patients had no back complaint at all. Of the 32 patients with pre–operative radicular symptoms, 30 were significantly improved. All 33 patients felt satisfied with the surgery. 30 of 33 patients had returned to previous occupation and level of activity. Radiographic fusion judged by plain radiographs was demonstrated in 31 patients (38 of 40 levels = 94%), with two patient showing signs of partial graft incorporation.

Conclusion:

Impacted PLIF's can alleviate symptoms of lumbar spondylolisthesis, segmental instability, recurrent herniated discs, neural foramen collapse, and degenerative disc disease. The radiographic fusion rate is comparable to other fusion techniques. The relatively short hospital stay, low complication rate, and subjective patient satisfaction add to the merit of this procedure.