Degenerative facet joint changes in lumbar percutaneous pedicle screw fixation without fusion.

BACKGROUND

Aim of the study was to evaluate degenerative lumbar facet-joints changes after percutaneous pedicle screw fixation (PPSF) in the treatment of lumbar fractures.

MATERIALS AND

METHODS

Thirty patients underwent short PPSF without fusion. CT-scan was performed in the pre- and post-operative time at four, eight and 12 months. The six zygapophyseal joints adjacent the fracture's level were evaluated.

RESULTS

At four months patients showed no differences between pre- and post-operative joint radiographic aspect. At eight and 12 months, CT-scan demonstrated a progressive degeneration only in the middle joints respectively in 21.42% and in 76.92% of the cases. All 10 disrupted facet joints showed progressive degenerative changes at eight and 12 months.

CONCLUSION

Lumbar percutaneous fixation without fusion induces little degenerations essentially collocated in the middle joints close to fracture level at eight and 12 months. In the proximal and distal joints adjacent the screws degenerative changes can be seen only when associated to pedicle-screw encroachment.