A novel surgical technique in transforaminal lumbar interbody fusion by the bone graft delivery device: evaluation of therapeutic effect in patients with minimally invasive spine surgery

Abstract

Background: Transforaminal Lumbar Interbody Fusion (TLIF) is commonly associated with higher complications and longer operative time. This study aims to evaluate the effectiveness, safety, and usability of a novel minimally invasive surgery (MIS) bone graft delivery device.

Methods: 73 consecutive patients with lumbar spondylosis, degenerative disc disease, spondylolisthesis, scoliosis or trauma were enrolled in this randomized controlled trial. Group 1 comprised 39 patients treated with the novel MIS bone graft delivery device. Group 2 consisted of 34 patients treated with the conventional system. The primary objective of the study was the assessment of the amount of bone graft delivery using the device. The secondary objectives were the effect of the device on operative time, pain relief, disability improvement, and bone fusion grade.

Results: Bone delivery amount was significantly higher in the MIS device group (6.7 ± 2.9 mL) compared to the conventional group (2.3 ± 0.5 mL), p < 0.001. Regarding the operation time, the MIS device group was associated significantly lower duration than the conventional group (p < 0.001). After a 3-month follow-up, 39.5% of the patients in the MIS device group and 3.5% of the patients in the conventional group were observed to achieve grade I fusion (complete fusion). There was a significant difference in fusion success rates (p < 0.01).

Conclusion: The novel MIS bone graft delivery device was associated with successful bone delivery. Our MIS device provides promising modality with less operative time and higher bone fusion rates than conventional modalities. Trial Registration This trial was retrospectively registered on ClinicalTrials.gov (Registration date: 11/19/2021; Registration number: NCT05190055).

Keywords: Bone fusion; Bone graft; MIS device; Minimally invasive surgery.

Conflict of interest statement

The authors declare no conflicts of interest.

© 2022. The Author(s).

Figures

Fig. 1

The bone graft delivery device. The novel device integrates the threaded rod into the filler tube allowing the granule bone graft to be driven deep into the empty disc space. The device can be connected with a surgical drill for rapid bone graft filling

Fig. 2

VAS and ODI in subjects receiving the 2 different graft filling techniques. Visual analogue scale (VAS) leg (A) and back (B) pain scores and Oswestry disability index (C) prior to and at each follow-up time points post operation in subjects receiving the 2 different graft filling techniques. There was no significant difference between the groups at each time point regarding VAS pain scores and ODI

Fig. 3

The amount of bone graft volume performed using Control group or MIS device group. The amount of bone graft volume performed using the traditional delivery method (Control group) or the novel device (MIS device group). The novel device significantly increased the volume of the bone graft material transplanted into the disc space. ***p 

Fig. 4

Representative radiography and computed tomography of surgical area of participant’s non-union and union cases. Representative radiography and computed tomography of surgical area of participant’s non-union and union cases. A X-ray image of the non-union and union case. Bone bridge (red arrow) was observed in the union case on X-ray taken 3 months post operation and the bone graft surrounding the cage (red arrow) was seen on X-ray taken 6 months after the surgery. B X-ray and CT images of the union cases receiving traditional or MIS graft delivery method. Bony formation and incorporation are indicated in yellow arrows

Fig. 5

The percentage distribution of grade fusion at each follow-up time points. The percentage distribution of grade I, II, and III fusion prior to and at each follow-up time points in cases with the traditional method or novel device. Grade I, II, and III indicates complete fusion, partially fusion, and no fusion of the cases

Fig. 6

Representative three-dimensional reconstruction computed tomography of bone fusion volume at 6 months post operation. Representative three-dimensional reconstruction computed tomography of bone fusion volume in cases receiving the traditional method or novel device at 6 months post operation. The bone fusion areas around and within the cage were indicated in blue and yellow respectively and the cage pin was depicted in red