POSTERIOR APPROACH WITH LOUIS PLATES FOR FRACTURES OF THE THORACOLUMBAR AND LUMBAR SPINE WITH AND WITHOUT NEUROLOGIC DEFICITS

Study Design. This is a retrospective revue of the long-term outcome o f posterior Louis plate fixation for the treatment of irreducible or l igamentously unstable fractures of the thoracolumbar and lumbar spine with or without neurologic deficit Objectives. To determine the clinic al, radiologic, and functional status of patients who underwent poster ior fracture fixation with Louis plates and to evaluate the effect of instrumentation length on the construct's ability to maintain reductio n of the fracture. Summary of Background Data. Since the development o f pedicle screw fixation described by Roy-Camille, there has been a ra pid evolution in the number and complexity of systems available for po sterior spinal stabilization. Along with this escalation in implant an d instrument sophistication, there has been a corresponding increase i n implant cost. To date, no series has been reported of the clinical, radiologic, and functional results of posterior instrumentation with s emirigid Louis plates for spinal fractures. Methods. A retrospective r eview of spinal fractures from T11 to L5 treated since 1985 by posteri or plate fixation showed that 56 patients (37 men and 19 women) with a n average age of 34 years and a minimum follow-up of 2 years (average, 41 months) were available for review. There were 36 burst fractures, 4 Chance fractures and 16 fracture-dislocations treated. Forty-three p atients had neurologic injury. Results. Before surgery, vertebral kyph osis averaged 15 degrees, improved to 5 degrees with reduction, and re ached a steady 10 degrees at final follow-up. Similarly, corrected kyp hosis initially averaged 12 degrees but improved to 0.5 degrees with r eduction, and was 10 degrees at final follow-up. Vertebral canal compr omise initially averaged 50% but was reduced to 13% with surgery and 6 % at 1 year. There was no significant difference between the ability o f short and long constructs to maintain reduction. Eighty-eight percen t of patients with neurologic injury improved at least one Frankel gra de with treatment. Functional and pain evaluation by the Denis scale s howed 25 patients rated P1, 25 rated P2, and 6 rated P3. Twenty-eight were rated W1, 16 were W3, and 12 were W5 at last follow-up. Conclusio ns. Fractures of the thoracolumbar spine can be treated effectively wi th the semirigid Louis plating system. Because of its low cost and eas e of insertion, the Louis system is an excellent choice for short arth rodesis and instrumentation of these fractures. Although there is some loss of reduction when compared with more rigid systems, there is no functional compromise in these patients.