Prophylactic Percutaneous Kyphoplasty Treatment for Nonfractured Vertebral Bodies in Thoracolumbar for Osteoporotic Patients

A nomogram for predicting fracture of the sandwich vertebrae after percutaneous vertebral augmentation: a multicenter study with 1-year follow-up

PURPOSE

This work aimed to investigate the risk factors for fractures in sandwich vertebrae (SDV; an unfractured vertebra located between 2 cemented vertebrae) formed after percutaneous vertebral augmentation (PVA) and to construct a predictive model from this.

METHODS

This study retrospectively analyzed patients who underwent PVA with the formation of SDV from July 2018 to July 2023 at Affiliated Banan Hospital of Chongqing Medical University. Patients were divided into a fracture group and a control group according to the presence or absence of fracture of the SDV during the 1-year postoperative follow-up period. Independent predictors were confirmed using the least absolute shrinkage and selection operator (LASSO) method, and the nomogram was constructed and transformed into an online calculator. The discrimination, calibration, and clinical applicability of the model were assessed by Area under the receiver operating characteristic curve (AUC), calibration curve analysis, and Decision curve analysis (DCA). Finally, the model was externally validated using data from another centre and internally validated using Bootstrap.

RESULTS

A total of 259 patients were enrolled in this study, and 36 patients had fractures of SDV within one year. Multifactorial analyses showed that low bone mineral density (BMD) (OR = 4.264, 95% CI: 2.245-8.098, P < 0.001), number of PVA > 3 (OR = 3.703, 95% CI: 1.399-9.801, P = 0.008), lack of anti-osteoporosis (OR = 4.051, 95% CI: 1.573-10.430, P = 0.004), postoperative kyphosis angle of sandwich fracture segments (PKASFS) > 10° (OR = 8.273, 95% CI: 2.991-22.881, P < 0.001), and lumbar lordosis minus thoracic kyphosis (LL-TK) < 0° (OR = 3.701, 95% CI: 1.523-8.994, P = 0.004) were screened as independent risk factors. The AUC of the model constructed based on this was 0.881 (95% CI: 0.829-0.933). The calibration curves and DCA verified that the model had satisfactory practical consistency and clinical applicability. The externally validated AUC was 0.859 (95% CI: 0.788-0.930), validating the stability of the model.

CONCLUSIONS

BMD, number of PVA, anti-osteoporosis, PKASFS, and LL-TK are independent influencing factors for fractures in SDV within one year, and a model based on this had excellent predictive efficacy.

Biomechanical evaluation of a novel minimally invasive pedicle bone cement screw applied to the treatment of Kümmel's disease in porcine vertebrae

Background and objective: Treatment of Kümmel's Disease (KD) with pure percutaneous kyphoplasty carries a greater likelihood of bone cement displacement due to hardened bone and defect of the peripheral cortex. In this study, we designed a novel minimally invasive pedicle bone cement screw and evaluate the effectiveness and safety of this modified surgical instruments in porcine vertebrae. Methods: 18 mature porcine spine specimens were obtained and soaked in 10% formaldehyde solution for 24 h. 0.5000 mmol/L EDTA-Na2 solution was used to develop in vitro osteoporosis models of porcine vertebrae. They were all made with the bone deficiency at the anterior edge of L1. These specimens were randomly divided into 3 groups for different ways of treatment: Group A: pure percutaneous kyphoplasty (PKP) group; Group B: unilateral novel minimally invasive pedicle bone cement screw fixation combined with PKP group; Group C: bilateral novel minimally invasive pedicle bone cement screw fixation combined with PKP group. The MTS multi-degree of freedom simulation test system was used for biomechanical tests, including axial loading of 500 N pressure, range of motion (ROM) in flexion, extension, left/right lateral bending, and left/right axial rotation at 5 Nm, and the displacement of bone cement mass at maximum angles of 5° and 10°. Result: The three groups were well filled with bone cement, no leakage or displacement of bone cement was observed, and the height of the vertebrae was higher than pre-operation (p < 0.05). In the left/right axial rotation, the specimens were still significantly different (p < 0.05) from the intact specimens in terms of ROM after PKP. In other directions, ROM of all group had no significant difference (p < 0.05) and was close to the intact vertebrae. Compared with PKP group, the relative displacement of bone cement in groups B and C was smaller (p < 0.05). Conclusion: In the in vitro animal vertebral models, the treatment of KD with the placement of novel pedicle minimally invasive bone cement screw combined with PKP can effectively restore the vertebral height, improve the stability of the affected vertebra and prevent the displacement of bone cement. Biomechanically, there is no significant difference between bilateral and unilateral fixation.

Association of IL-6 and TGF-β Gene Polymorphisms with the Risk of Thoracolumbar Osteoporotic Vertebral Compression Fractures

Purpose

Osteoporotic vertebral compression fracture (OVCF) is a common disease in the elderly, and genetic factors play a key role in its occurrence. The present study was conducted to investigate the association between interleukin-6 (IL-6) and the transforming growth factor (TGF-β) gene polymorphisms and the occurrence of thoracolumbar OVCF.

Patients and Methods

This case–control study recruited 146 patients with OVCF and 144 osteoporosis patients as the control group. Genotypes of the IL-6 rs1800796 and TGF-β rs1982073 were analyzed by sequencing. Genotype distribution and allelic frequencies were investigated by the χ² test. Odds ratios (OR) and 95% confidence intervals (CI) evaluated the relationship of IL-6 or TGF-β polymorphism and OVCF susceptibility.

Results

Allele G and genotype GG of IL-6 rs1800796 was more frequent in patients with OVCF (40.07% vs.28.47%; 19.18% vs.7.64%) compared with controls. GG genotype (OR=3.394, 95% CI=1.560–7.385, P < 0.001) and G allele (OR=1.680, 95% CI=1.187–2.376, P < 0.001) of IL-6 rs1800796 was significantly associated with increased risk of OVCF. What is more, CT and TT genotypes (41.78 vs.51.39; 19.86 vs.26.39) and allele T (40.75 vs 52.08) of TGF-β rs1982073 were less frequent in OVCFs, more common in controls and protective against OVCF risk (OR=0.436, 95% CI=0.228–0.835, P = 0.012; OR=0.615, 95% CI=0.443–0.855, P = 0.004).

Conclusion

Our results suggest that the G allele and GG genotype of IL-6 rs1800796 may contribute to increased susceptibility to OVCF in elderly Chinese. In contrast, CT and TT genotypes and the T allele of TGF-β rs1982073 may contribute to lower susceptibility of OVCF.

Comparison of Percutaneous Kyphoplasty with or without Pedicle Screw Fixation in Osteoporotic Thoracolumbar Vertebral Fractures: A Retrospective Study

Background

Osteoporotic thoracolumbar compression fractures have become a great social burden due to the aging tendency of population. This study is aimed at comparing the clinical and radiological outcomes of percutaneous kyphoplasty with or without pedicle screw fixation in patients with osteoporotic thoracolumbar fractures. Hypothesis. There is a difference in clinical outcomes between percutaneous kyphoplasty with pedicle screw fixation and percutaneous kyphoplasty.

Methods

This retrospective study included 87 patients who received percutaneous kyphoplasty with or without pedicle screw fixation between October 2015 and October 2017 at Ningbo No.6 Hospital and were followed for 2 years. A total of 40 patients received percutaneous kyphoplasty with pedicle screw fixation (PKPF group), and the other 47 patients had percutaneous kyphoplasty only (PKP group). The outcomes were measured using the visual analogue scale (VAS), Oswestry Disability Index (ODI), Cobb angle (CA), and anterior vertebra height rate (AVHr), which were calculated at preoperative admission and each follow-up visit. Complications including postoperative back pain, refracture, and fixation failure were collected from medical records.

Results

There was no significant difference in baseline characteristics or preoperative data between the two groups (p < 0.05) but significantly better improvements in VAS, ODI, CA, and AVHr at 12- and 24-month follow-up visits in the PKPF group compared with those of the PKP group. 23 (48.9%) patients in the PKP group had complications, whereas only 5 (12.5%) patients in the PKPF group presented complications including 2 postoperative back pain and 1 fixation failure (p = 0.04).

Conclusions

PKPF obtained longer correction and better improvement in VAS, ODI, and CA in patients with osteoporotic thoracolumbar vertebral fractures than PKP.

Does prophylactic vertebral augmentation reduce the refracture rate in osteoporotic vertebral fracture patients: a meta-analysis

PURPOSE

In order to prevent the recurrent fracture after vertebral augmentation, the concept of prophylactic vertebral augmentation has been proposed, but its efficacy is still controversial. This study aimed to determine the efficacy of prophylactic vertebral augmentation for prevention of refracture in osteoporotic vertebral fracture patients.

METHODS

Following PRISMA guidelines, a literature search was performed using PubMed, Embase and Web of Science databases for relevant studies published until February 2021. A meta-analysis of randomized controlled trials and retrospective controlled trials comparing prophylactic group versus nonprophylactic group was conducted. The primary outcome was the incidence of new vertebral compression fracture (VCF), and secondary outcomes were incidence of adjacent vertebral fracture (AVF) and remote vertebral fracture (RVF).

RESULTS

A total of 6 studies encompassing 618 patients were included in the meta-analysis. The incidence of new VCF was reported in all six studies, and the result showed no significant difference between the two groups (OR: 0.509; 95% CI: 0.184-1.409). Four studies provided data on the incidence of AVF, and it was revealed that there was no significant difference between the two groups (OR: 0.689; 95% CI: 0.109-4.371). In view of the incidence of RVF, prophylactic group also did not differ significantly compared with nonprophylactic group (OR: 0.535; 95% CI: 0.167-1.709).

CONCLUSIONS

The current evidence suggested that prophylactic vertebral augmentation might not be appropriate to diminish the risk of new VCF. Therefore, there is a need to investigate the mechanism of refracture and explore other preventive regimens to reduce the risk.