Minimally invasive approach versus traditional open approach for one level posterior lumbar interbody fusion.

OBJECTIVE: While over the last ten years minimally invasive posterior lumbar interbody fusion (PLIF) has been acknowledged to (i) reduce approach-related morbidity associated with quicker recovery, (ii) require a shorter hospital stay and (iii) deliver similar clinical outcomes when compared to a traditional approach, it is still not the current gold standard. In order to demonstrate the efficacy of the minimally invasive lumbar PLIF approach, a retrospective study was conducted comparing both approaches.

METHODS: A retrospective study was conducted with 40 patients treated for one level, degenerative lumbar instability. 20 patients received lumbar PLIF though a standard open approach, while another 20 underwent a minimally invasive approach using the "SpiRIT"-system. Spinal pathological features, stabilized segments, number of implanted pedicle screws, surgical time, radiation time, blood loss, complications, radiographic images and standardized patient questionnaires (VAS, ODI) were evaluated. The follow-up period was one year.

RESULTS: One year after the performed surgery, we found no significant difference between the two groups with regard to clinical and radiographic outcome. However, in the minimally invasive group we noticed less blood loss, less postoperative pain, a shorter recovery time and a shorter hospital stay. Despite these benefits, the minimally invasive group also experienced a longer surgical and radiation time as compared to the "open" group.

CONCLUSIONS: This study confirmed the results of previous studies which advocated the advantages of less blood loss, less postoperative pain, quicker recovery and shorter duration of hospitalization. However, in the long run, one year after surgery, both groups showed no significant difference with regards to clinical and radiographic outcome. Therefore long-term controlled studies are necessary to validate the role of the minimally invasive PLIF in degenerative lumbar instability.