LESS INVASIVE LUMBAR SPINE FUSION: A COMPARISON STUDY

Abstract

The aim of the prospective study was to examine advantages and disadvantages of less invasive spine fusion in comparison with traditional fusion technique.

In the literature there exists no comparison study of less invasive fusion technique with traditional fusion technique.

In the prospective comparison study 2 groups were compared: Group I, percutaneous fusion, and group II a traditional medial approach to the lumbar spine.

In all two groups monosegmental or bisegmental fusions in the lumbar spine were performed. From january 2005 to september 2007 147 patients with oste-chondrosis, spondylolisthesis and failed back surgery syndrom were operated. In all cases fusion with autogenic or allogenic bone graft was perfomed. In group I the mean age at operation was 48 years (range from 35 to 63), 72 patients (39 women, 33 men); and in group II the mean age at operation was 39 (35–73), 75 patients (43 women, 32 female). For the clinical examination VAS, a patient satisfaction score and a SF 36 were used. A monosegmental fusion was performed in group I in 60 cases and in group II in 45 cases. A bisegmental fusion was done in group I in 12 cases and in group II in 30 cases in the lumbar spine.

The mean follow up was 18 months (range from 3 months to 34 months). The mean time of operation was in group I 65 minutes (55 to 125); blood loss was in mean 25 ml (10 to 150), skin incision 4.5 cm (4 to 8cm). In group II mean time of operation 75 minutes (50 –120), blood loos 600 ml (350–600), and skin incision 12 cm (9–15). There was no statistical significant difference between the both groups in VAS, SF 36, and patient satisfaction score after 1 year follow-up. There was none infection, none neurological complication. In group I in two cases a revision surgery was necessary in cause of medial misplacement of the pedicle screw. No broken rod or broken screw was seen. The fusion rate was 85% in both groups.

The prelimanary results have shown that percutaneous pedicle screw instrumentation is a reliable technique and has advantages comparing traditional open procedure. However more prospective comparison study of a open and minimal percutaneous procedure with long time follow up are necessary.