Background: Symptomatic lumbar degenerative disc disease is a
challenging entity to treat. The results of arthrodesis may be compromised in
the short term by pseudarthrosis and in the long term by pain at the
iliac-crest donor site and by junctional degeneration. Total disc replacement
has the potential to provide long-lasting relief to these patients. The
purpose of this study was to present the clinical and radiographic results
assessed seven to eleven years following a Prodisc total lumbar disc
Methods: Sixty-four patients had single or multiple-level
implantation of a total lumbar disc replacement between 1990 and 1993. The
mean duration of follow-up was 8.7 years. Clinical results were evaluated by
assessing preoperative and postoperative lumbar pain, radiculopathy,
disability, and modified Stauffer-Coventry scores. Preoperative and
postoperative radiographs were evaluated as well. Subgroup analysis was
performed to determine if gender, an age of less than forty-five years,
previous surgery, or multilevel surgery had an effect on outcome.
Results: At an average of 8.7 years postoperatively, there were
significant improvements in the back-pain, radiculopathy, disability, and
modified Stauffer-Coventry scores. Thirty-three of the fifty-five patients
with sufficient follow-up had an excellent result, eight had a good result,
and fourteen had a poor result. Neither gender nor multilevel surgery affected
outcome. An age of less than forty-five years and prior lumbar surgery had
small but significant negative effects on outcome. Radiographs did not
demonstrate loosening, migration, or mechanical failure in any patient. Five
patients had approach-related complications.
Conclusions: The Prodisc lumbar total disc replacement appears to be
effective and safe for the treatment of symptomatic degenerative disc disease.
Gender and multilevel surgery did not affect the outcomes, whereas prior
lumbar surgery or an age of less than forty-five years was associated with
slightly worse outcomes. Longer follow-up of this cohort of patients and
randomized trials comparing disc replacement with arthrodesis are needed.
Level of Evidence: Therapeutic Level IV. See Instructions
to Authors for a complete description of levels of evidence.