Abstract
Background: Lumbar degenerative scoliosis is often accompanied by osteophytes on the concave side of scoliosis. In some cases, the intervertebral spaces and facet joints are fused osseously. It is recommended to break the osseous fusion before cage insertion to correct the scoliosis. We performed dissection of the intervertebral space osseous fusion from the anterior approach alone without posterior osteotomy of osseous fused facet before LIF cage insertion. In the present study, we investigated the local correction angle of intervertebral wedge deformity, endplate injury, and pedicle fracture in LIF cage insertion into intervertebral space with wedge-shaped spontaneous osseous fusion.
Method: The subjects were 4 intervertebral levels in 3 cases with wedge-shaped spontaneous osseous fusion (1 male, 2 females, average 62.6 years old). We approached from the convex side of scoliosis, broke the intervertebral osseous bridge with a chisel, and inserted LIF cage. We investigated the level of fused intervertebral space, intervertebral wedge of preoperative and postoperative, and the local correction angle of intervertebral spaces at coronal image of CT, and the presence or absence of endplate injury and pedicle fracture.
Result: Regarding as intervertebral level, three levels were at L3/4, one level was at L4/5. Local coronal correction angle of intervertebral wedge deformity was −1-9 degrees (the average is 3.7 degrees). One endplate injury and one pedicle fracture occurred in 4 levels.
Conclusion: LIF cage insertion in intervertebral osseous fusion may cause endplate injury and pedicle fracture, but can be corrected with less invasion. LIF at intervertebral space with osseous fusion of intervertebral space and facet joint without posterior osteotomy of osseous fusion is useful for coronal correction.
