Are short constructs improved with crosslinkage when interbody support is used? A clinical and radiographic outcomes study

2009

SUMMARY
The standard biomechanical testing of pedicle screw constructs includes crosslinks between rods. Though crosslinks have been studied in long constructs, they have not been studies in short-segment fusions. Clinical and radiographic outcomes were prospectively studied in 135 consecutive patients undergoing short-segment instrumented fusions and TLIF with cage: 72 with, and 63 without crosslinks. There was no difference in complications, fusion rates, or clinical outcomes when using a crosslink.

INTRODUCTION

Standard implant testing for FDA approval requires cross linkages between rods. This study compared clinical and radiographic outcomes of patients undergoing short-segment posterior instrumented fusion (PSF) and cage TLIF with and without a rod crosslinkage.

METHODS

Prospective non-randomized study of 135 adults with PSF and TLIF at 1-2 levels (avg 1.6 levels) for degenerative disease, and followed avg 23 months (12-40 mo). Crosslinks between rods were used in 72, no crosslinks in 63. Oswestry (ODI), pain scores (VAS), and radiographs were studied pre-op, 1 and 2yrs.

RESULTS

Complications: 1 nonunion, 1 adjacent fracture, 3 infections, 1 footdrop, 3 revisions for adjacent degeneration. There was no statistical difference between groups for complications. ODI (avg 49.7 pre, 25.7 at 1 yr, 22.6 at 2 yr) and VAS (6.3 pre, 3.0 at 1 yr and 2 yr) were not different between groups.

CONCLUSION

Short segment posterior instrumented fusion with structural TLIF does not require rod crosslinks to achieve optimal clinical results with minimal complications.

SIGNIFICANCE

Crosslinks are not required in short-segment fusions with TLIF.