Clinical and radiographic comparison of mini-open transforaminal lumbar interbody fusion with open transforaminal lumbar interbody fusion in 42 patients with long-term follow-up.

OBJECT: As minimally invasive approaches gain popularity in spine surgery, clinical outcomes and effectiveness of mini-open transforaminal lumbar interbody fusion (TLIF) compared with traditional open TLIF have yet to be established. The authors retrospectively compared the outcomes of patients who underwent mini-open TLIF with those who underwent open TLIF.

METHODS: Between 2003 and 2006, 42 patients underwent TLIF for degenerative disc disease or spondylolisthesis; 21 patients underwent mini-open TLIF and 21 patients underwent open TLIF. The mean age in each group was 53 years, and there was no statistically significant difference in age between the groups (p = 0.98). Data were collected perioperatively. In addition, complications, length of stay (LOS), fusion rate, and modified Prolo Scale (mPS) scores were recorded at routine intervals.

RESULTS: No patient was lost to follow-up. The mean follow-up was 24 months for the mini-open group and 34 months for the open group. The mean estimated blood loss was 194 ml for the mini-open group and 505 ml for the open group (p < 0.01). The mean LOS was 3 days for the mini-open group and 5.5 days for the open group (p < 0.01). The mean mPS score improved from 11 to 19 in the mini-open group and from 10 to 18 in the open group; there was no statistically significant difference in mPS score improvement between the groups (p = 0.19). In the mini-open group there were 2 cases of transient L-5 sensory loss, 1 case of a misplaced screw that required revision, and 1 case of cage migration that required revision. In the open group there was 1 case of radiculitis as well as 1 case of a misplaced screw that required revision. One patient in the mini-open group developed a pseudarthrosis that required reoperation, and all patients in the open group exhibited fusion.

CONCLUSIONS: Mini-open TLIF is a viable alternative to traditional open TLIF with significantly reduced estimated blood loss and LOS. However, the authors found a higher incidence of hardware-associated complications with the mini-open TLIF.