Abstract
Introduction This study was conducted to compare bone-filled intervertebral cages with autologous
bone chips for instrumented lumbar interbody fusion in patients with spinal stenosis
and degenerative spondylolisthesis.
Methods Surgery consisted of posterior instrumentation and decompression, diskectomy, and
intervertebral fusion using a polyetheretherketone (PEEK) cage surrounded and filled
with spongious bone chips (group 1, n = 57) or spongious bone chips alone (group 2, n = 37). The choice of method was left to the discretion of the surgeon. Postoperative
results were prospectively evaluated using a standardized protocol. Radiological assessment
included fusion rates and vertebral height, while clinical assessment included the
visual analog scale (VAS) and Oswestry Disability Index (ODI).
Results In group 1, a mean of 1.38 ± 0.64 segments were fused. In group 2, a mean of 1.58 ± 0.65
segments were fused. In both groups, the VAS for back pain and leg pain and the ODI
improved without significant differences between the two groups. Osseous fusion was
documented by computerized tomography in 73% in group 1 and 89% in group 2 after a
mean of 18 months. The loss of height was 2.8 ± 4.0% in group 1 and 2.4 ± 5.2% in
group 2.
Conclusion Regardless of whether a PEEK cage filled with spongious bone chips or spongious bone
chips alone were used for lumbar interbody fusion, clinical parameters improved significantly
after surgery. There were no significant differences in the rate of bony fusion and
loss of height between the two groups. The results of this nonrandomized cohort study
indicate that the implantation of autologous spongious bone chips harvested during
the decompression procedure is a useful and cheap alternative to an intervertebral
cage in patients with degenerative pseudospondylolisthesis.
Keywords
degenerative - spondylolisthesis - instrumented fusion - cage - PEEK - autologous
- bone chips - spongious bone
