Midline Sparing Bilateral PLIF with Single Side Plate/Contralateral Cage Stabilization

John L. Zinkel MD, PhD

Introduction: A hybrid PLIF surgery combines midline sparing bone/soft tissue dissection with single side screw/plate, contralateral cage stabilization. It was used on 68 adults (9/97 to 8/98) for stenosis/instability and/or intractable joint pain.

Methods: Skin is incised at midline 4 cm for one level PLIF (6 for 2). Fascia is opened 2 cm off midline each side, with multifidi "split" obliquely to spare attachments, with total facetectomies, and discectomies. Screw/plate fixation on right distracts discs, reduces listheses, and adds lordosis. Left PLIF is with local bone/cage, and right, with local bone/allograft. Closure includes i.t. morphine and drain. Results: 68 adults were fused (84 levels) with 40 patients over 12 months post–op. Interim fusion rate is 98.8% (83/84). Two were reoperated: one percutaneously for loose nut; one for misplaced cage/ nonunion. One had foot drop, and three, radicular dysesthesias. No deaths, dural tears, transfusions, deep infections, DVT'S, or recurrences of deep joint or radicular pain. Lumbosacral myofascial aching does occur.

Discussion: Careful midline sparing dissection cuts blood loss and myofascial morbidity. Total facetectomy decompresses widely and frees local bone as autograft. Hybrid fixation blends screw/plate rigidity and spine contouring with cage distraction, adding translation/rotational stability. Most PLIF bone is outside the cage. Thus metal is removable with stability preserved.

Conclusion: This PLIF technique is minimally invasive, reliable, and cost effective. Data will be presented.