Abstract
Introduction: Fusion is typically indicated for degenerative spinal disorders with concomitant instability or painful spondylosis. Numerous techniques are used, with considerable variation in their invasiveness, risks and costs, although few can boast superiority for a given indication, particularly in relation to patient-orientated outcomes. This cohort study compared outcomes after fusion with translaminar screws (TS) versus transforaminal lumbar interbody fusion plus pedicular fixation (TLIF) plus pedicular fixation (both with decompressive procedures).
Methods: The study was nested within our SSE Spine Tango data acquisition system. The suitability (or otherwise) for inclusion of every Spine Unit patient was indicated at the pre-operative consultation. Inclusion criteria: mono/bisegmental degenerative disc disease, facet syndrome or degenerative spondylolisthesis; German language; no previous surgery (except discectomy). Each surgeon consistently used his pre-stated, preferred method (TS or TLIF) for all his patients fitting the inclusion criteria. Before and 12 and 24 months post-surgery, patients completed the multidimensional Core Outcome Measures Index (COMI; 0–10 scale); after 12-months, global outcome was rated on a Likert-scale and dichotomised into “good” and “poor” groups.
Results: 121 patients took part; 57 in the TS group (1 surgeon) and 64 in the TLIF group (4 surgeons). Gender distribution was identical in the two groups (67% women); TS were significantly older than TLIF (67±10y and 56±15y respectively, p< 0.05). There were no significant group differences at baseline for any COMI domain scores (all p> 0.05). TS had a significantly lower operation duration (p=0.0001) and blood-loss (p=0.01) but a longer hospital stay (p=0.005) than TLIF. Complication rates prior to discharge were similar in each group (2–4%). 94% patients returned questionnaires at 12-months. The groups did not differ in: reduction in COMI score, 3.5±2.9 (TS) vs 4.1±2.6 (TLIF)(p=0.23); % good outcomes, 72% (TS) vs 77% (TLIF)(p=0.58); satisfaction with treatment, 82% (TS) vs 88% (TLIF) (p=0.36). Thus far, 75 patients have reached the 2-yr follow-up and the trend for no group differences remains: % good outcomes, 81% (TS) vs 79% (TLIF)(p=0.91); satisfaction with treatment, 83% (TS) vs 85% (TLIF) (p=0.88)
Discussion: This cohort study showed similar subjective results up to 2 years later for two different surgical techniques done for identical indications, but with differing surgical time, invasiveness and implant costs. The data thus far suggest that, for these degenerative disorders, optimal but invasive three-point stabilization is not required to achieve satisfactory results. Although the study design is not the highest in the “hierarchy-of-evidence”, it includes every single eligible patient and allows each surgeon to use his regular surgical procedure; it hence represents a practicable, complementary approach to the randomised-controlled-trial, with higher external validity (relevance/generalisability).
Correspondence should be addressed to Dr Owen Williamson, Editorial Secretary, Spine Society of Australia, 25 Erin Street, Richmond, Victoria 3121, Australia.
