Adult degenerative scoliosis associated with increased aortic diameter and plaque burden and composition

Risk factors for celiac artery and superior mesenteric artery stenosis in preoperative lumbar and thoracolumbar spinal surgery patients

BACKGROUND

Ischemic necrosis of the abdominal organs caused by compression of the celiac artery (CA) and superior mesenteric artery (SMA) by the median arcuate ligament (MAL) after correction surgery has been recognized as acute celiac artery compression syndrome (ACACS). Here, using contrast-enhanced computed tomographic (CT) images, we sought to determine the prevalence and degree of CA and SMA stenosis in spinal patients preoperatively, and the risk factors associated with the stenosis.

METHODS

We retrospectively examined contrast-enhanced abdominal CT of 90 patients with preoperative lumbar degenerative disease, lumbar burst fracture, or adult spinal deformity. The trunks of the CA and SMA were detected using three-dimensional reconstructed CT. To investigate their degree of stenosis, we determined the ratio of the narrowest diameter of the stenotic segment to the distal normal lumen's diameter. Patients with a degree of stenosis ≥35% were defined as being in the group with stenosis and the remainder as in the group without. To determine the risk factors for stenosis of these arteries, the relationship between the stenosis and CA and SMA calcification or the median arcuate ligament (MAL) crossing the proximal portion of the celiac axis (MAL overlap) was also investigated.

RESULTS

The average degree of stenosis of the CA trunk was 12.1% ± 13.9% and that for the SMA trunk was 8.5% ± 8.8%. There were 8 patients (8.9%) in the group with CA stenosis and 2 patients (2.2%) in the group with SMA stenosis. The number of patients in the group with CA stenosis was significantly greater than the number with MAL overlap or CA calcification (P < 0.05).

DISCUSSION

The prevalence of CA or SMA stenosis was 11.2% of preoperative patients due to undergo thoracolumbar fusion surgery. Calcifications of the CA trunk and MAL overlap are risk factors for CA stenosis.

The position of the aorta relative to the spine in patients with adult degenerative scoliosis

Study design

A retrospective analysis was conducted to analyze the position of the aorta by MRI in patients with adult degenerative scoliosis.

Objective

This study aimed to investigate the relative anatomic positions of the aorta and spine in patients with adult degenerative scoliosis (ADS).

Summary of background data

Aorta injury is a rare complication of spinal surgeries. However, there would be a disastrous consequence once it happened. Therefore, knowing about the position of aorta is of great importance.

Methods

A retrospective analysis was performed in 90 patients with ADS and 132 participants without spine deformity. ADS patients were divided into several groups such as left scoliosis, left scoliosis with thoracolumbar kyphosis, right scoliosis, and right scoliosis with thoracolumbar kyphosis. The aorta-vertebrae angle (α) and aorta-vertebrae distance (d) in each level of T12–L4 were measured by using a Cartesian coordinate system. t test of independent samples was performed, α and d were compared, and Pearson correlation analysis was employed for α, d, and X-ray radiographic measurements.

Result

The changes of α were not statistically significant (P > 0.05) in LS and LKS groups but d (P < 0.05) was longer in LKS group compared with the control group. In the right malformed group, there was no significant change in the angle (P > 0.05) in the abdominal aorta but longer d (P < 0.05) than the normal group. There was longer d in the RKS group compared with the RS group (P < 0.05). Pearson correlation analysis showed that there was a positive correlation between d and TLK (r = 0.439, P < 0.05).

Conclusion

In patients with ADS, a relative normal position is maintained between the aorta and vertebrae. While the aorta is slightly away from the left pedicle in RS patients and farther away in patients with kyphosis, the angle of kyphosis would become bigger and d becomes longer. Therefore, the surgeons should be aware of the changes of the aorta position to avoid the disastrous vessel injuries.

Position of the Aorta Relative to Vertebrae in Patients with Degenerative Thoracolumbar or Lumbar Scoliosis: A Case-Control Study

OBJECTIVE

To investigate the position of the aorta relative to the spine in patients with de novo lumbar scoliosis (DLS).

METHODS

This study enrolled 142 patients with DLS, including 80 cases of left thoracolumbar/lumbar scoliosis (left group) and 62 cases of right scoliosis (right group). In addition, 132 cases free of deformity were allocated to the control group. Parameters of the Cobb angle and apical vertebrae were measured by radiograph, whereas the left pedicle-vertebrae angle (α), rotation angle (γ), and left pedicle-vertebrae distance (d) of T12-L4 were obtained by magnetic resonance imaging. Independent sample t test was performed to compare α, γ, and d between the DLS and control groups, followed by a Pearson correlation analysis to study the correlation between Cobb angle and α, γ, and d.

RESULTS

No difference was found between the right group and control group (P = 0.554). The value of mean d (4.62 ± 0.57 cm) gradually increased from T12 to L4 in the left group and showed significant difference with the corresponding value in the control group (4.44 ± 0.43 cm; P < 0.001). There was no significant difference between the right group and control group (P = 0.762). The value of mean d (4.54 ± 1.84 cm) showed no significant difference between the right group and control group (P = 0.530). The correlation analysis showed a significant correlation between rotation angle γ and Cobb angle (P < 0.001), but not in α and d with Cobb angle.

CONCLUSIONS

Although the position of the aorta relative to the spine showed no significant difference between patients with DLS and normal subjects, great attention should still be paid to prevent DLS-induced aorta injury.

Mesenteric ischemia following the correction of adult spinal deformity: case report

Vascular complications are an important adverse event that can be associated with spinal reconstructive surgery. Direct injury of vessels, or indirect traction or compression of vessels, can cause both arterial and venous injury. Indirect compression of the mesenteric vessels is a well-recognized complication of bracing and surgical care of children with spinal deformity (superior mesenteric artery syndrome), but the complication is not common or well recognized in the adult population with spinal deformity. The purpose of this case report is to detail the case of postoperative mesenteric ischemia in a 63-year-old man in whom a posterior approach was used to perform spinal deformity correction. Preoperatively, the patient had had significant lumbar hypolordosis. The reconstructive surgery with the use of posterior-based osteotomies resulted in a shortening of the posterior column of the spine but a relative lengthening of structures anterior to the spine. The significant lordosis achieved by the surgery led to an acute worsening of the mesenteric stenosis suffered by the patient. He required a vascular surgery intervention to restore perfusion to the bowel. Recognition of severe vasculopathy is important in anticipating potential postoperative vascular insufficiency. This case report will inform surgeons and clinicians to have a higher index of suspicion for the exacerbation of vascular insufficiency, including mesenteric pathology, in patients undergoing surgery that involves significant realignment of the spine. Preoperative recognition of vascular insufficiency and treatment of symptomatic disease may limit the occurrence of postoperative vascular complications in spinal reconstructive surgery.