J. Soini et al., EXTERNAL TRANSPEDICULAR FIXATION-TEST OF THE LUMBAR SPINE CORRELATES WITH THE OUTCOME OF SUBSEQUENT LUMBAR FUSION, Clinical orthopaedics and related research, (293), 1993, pp. 89-96
External transpedicular fixation was applied to the lower lumbar spine
in a prospective study on 42 patients with chronic low back pain comb
ined with suspected instability of the lumbar segments; the diagnosis
was failed disk surgery, spondylolisthesis, and degenerative disk dise
ase. The aim was to realign the involved segments, to restore disk hei
ght, and to record changes in pain and performance during the external
fixation test. Pain was recorded on a visual analog scale, and perfor
mance was assessed using the Oswestry disability score. An independent
observer assessed the test and treatment results. Twenty-nine patient
s experienced relief of pain and performed better in the fixator; they
were subjected to anterior interbody fusion, the external frame being
kept as a stabilizing device for an additional four months. Twenty-tw
o patients have had follow-up evaluations for two years. One and two y
ears after successful lumbar fusion, significantly (p < 0.02) better p
ain and performance scores were recorded; the results of lumbar fusion
corresponded to the preoperative fixation test. A temporary external
fixation test may be a useful procedure in patients considered for sub
sequent spondylodesis.