Severe kyphotic deformity resulting from collapses of cemented and adjacent vertebrae following percutaneous vertebroplasty using calcium phosphate cement. A case report

Incidence, Risk Factors, and Outcomes of Symptomatic Bone Cement Displacement following Percutaneous Kyphoplasty for Osteoporotic Vertebral Compression Fracture: A Single Center Study

STUDY DESIGN

Retrospective.

BACKGROUND

Symptomatic bone cement displacement (BCD) is a rare complication following percutaneous kyphoplasty (PKP) interventions for osteoporotic vertebral compression fracture (OVCF). This study aimed to investigate the incidence and the outcomes of symptomatic BCD comprehensively and identify its risk factors.

METHODS

The clinical data of patients treated with PKP for OVCF between January 2012 and December 2020 were extracted. Patients who developed BCD following PKP during follow-up were divided into the symptomatic and asymptomatic groups. Patients who did not develop BCD were assigned to the control group. Univariate and multiple logistic regression analyses were used to compare the three clinical groups' features to assess the independent risk factors for the symptomatic and asymptomatic groups.

RESULTS

A total of 896 patients were enrolled. Twenty-one patients (2.3%) were identified as having symptomatic BCD following PKP for OVCF, and 35 (3.9%) developed asymptomatic BCD. Compared with the control group, the symptomatic and asymptomatic groups had a higher incidence of anterior leakage, intravertebral vacuum cleft (IVC) signs, and a lower cement distribution score. The symptomatic group had a lower relative cross-sectional area (rCSA) of the paraspinal muscle (PSM), higher PSM fatty degeneration, and higher kyphotic angle (at the last follow-up) than the asymptomatic and control groups. For outcomes, the symptomatic group had a higher VAS/ODI score and a higher incidence of new vertebral fractures compared with the asymptomatic and control groups. Anterior leakage (OR: 1.737, 95% CI: 1.215-3.300), the IVC sign (OR: 3.361, 95% CI: 1.605-13.036), the cement distribution score (OR: 0.476, 95% CI: 0.225-0.904), PSM rCSA (OR: 0.953, 95% CI: 0.917-0.992), and PSM fatty degeneration (OR: 1.061, 95% CI: 1.005-1.119) were identified as independent risk factors for the symptomatic group. Anterior leakage (OR: 1.839, 95% CI: 1.206-2.803), the IVC sign (OR: 2.936, 95% CI: 1.174-9.018), and cement distribution score (OR: 0.632, 95% CI: 0.295-0.858) were independent risk factors for the asymptomatic group.

CONCLUSION

The incidence of symptomatic BCD is 2.3% in patients treated with PKP. Anterior leakage, the IVC sign, and the distribution score were independent risk factors for BCD, and paraspinal muscle degeneration was a specific risk factor for symptomatic BCD. Symptomatic BCD can lead to poor outcomes.

Vertebral collapse and polymethylmethacrylate breakage after vertebroplasty: A case report

RATIONALE

Vertebral augmentation has become the main treatment for osteoporotic vertebral fractures (VFs). In this article, we report a very rare case of vertebral collapse and polymethylmethacrylate (PMMA) breakage after vertebroplasty. We describe the clinical characteristics and revision surgery performed to remove the broken PMMA cement, maintain stability, and corrects the kyphotic deformity, and we analyze the possible causes.

PATIENT CONCERNS

A 72-year-old man who suffered back pain underwent first lumbar vertebra (L1) percutaneous vertebroplasty (PVP) due to osteoporosis and a vertebral fracture in May 2013. Postoperatively, the patient's back pain was markedly alleviated. Unfortunately, his lumbar back pain recurred in November 2015.

DIAGNOSES

Plain radiographs showed collapse of the L1 vertebral body, breakage of the PMMA cement, and severe kyphosis at the thoracolumbar junction.

INTERVENTIONS

The posterior pedicle was internally fixed and an anterior artificial vertebral body implant was placed to maintain stability and correct the kyphotic deformity in a 2-step surgical procedure.

OUTCOMES

The back pain was alleviated and the patient returned to daily life for more than two years.

LESSONS

This case demonstrates that PVP is not a simple minimally invasive surgery, and significant postsurgical care is necessary. The true cause of this rare phenomenon remains unclear, but the long-term use of steroids, new injuries, and poorly corrected kyphosis after PVP may play a role. Surgeons must be aware of the kinds of complications that may occur, including rare complications such as vertebral lysis.

Percutaneous Balloon Kyphoplasty Vertebral Augmentation for Compression Fracture Due to Vertebral Metastasis: A 12-Month Retrospective Clinical Study in 72 Patients

Background

Vertebral compression fracture is common in osteoporosis, but can also occur due to bone metastases, for which current treatment options are limited and include bone-strengthening with cement and supportive care. Kyphoplasty is a surgical method of bone augmentation that can reduce pain, stabilize vertebral bone, and restore some or all of the vertebral body height. The aim of this study was to investigate the clinical results of balloon kyphoplasty in the correction of vertebral deformity due to metastatic vertebral compression fracture.

Material/Methods

A retrospective clinical study included 72 patients (82 vertebral bodies) with metastases resulting in vertebral compression fracture, treated by percutaneous balloon kyphoplasty; 9 patients were found incidentally to have vertebral metastases. Bone mineral density (BMD) levels were measured. Patient responses from questionnaires, including the visual analog scale (VAS) for pain intensity, and the Oswestry Disability Index (ODI) for disability, were scored. The local kyphosis angle (KA) and the vertebral height ratio (VHR) were measured. All patients were followed up for 12 months. The initial postoperative and 12-month postoperative values, and the preoperative and postoperative values were compared.

Results

Following balloon kyphoplasty, the KA, VHR, VAS, and ODI scores significantly improved at the final 12-month follow-up compared with preoperative levels (p<0.05, and p<0.001). There was cement leakage in 6 procedures (8.3%) and adjacent segment fracture in 11 procedures (15.2%).

Conclusions

Balloon kyphoplasty was an effective method to reduce pain, reduce disability, and improve quality of life by eliminating kyphotic deformity in pathological vertebral compression fractures due to vertebral metastases.

[Low cement distribution index is a risk factor for refracture of the adjacent segments after percutaneous vertebroplasty]

OBJECTIVE

To investigate the impact of cement distribution index on the occurrence of refracture in the adjacent segments after percutaneous vertebroplasty.

METHODS

This retrospective analysis was conducted among 143 patients who received percutaneous vertebroplasty for osteoporotic vertebral compression fracture between April, 2011 and April, 2014. Of the 134 patients with complete follow-up data, 18 had adjacent segment fracture within 1 year following the surgeries (re-fracture group), and 116 patients without new fracture served as the control group. All the patients underwent X-ray examinations after the surgery and according to the position and shape, the cement in the vertebrae were classified into 5 types (I to V), and the volume-cubage index was computed based on the cement volume and vertebral cubage. Age, gender, bone mineral density (BMD), cement distribution index, volume-cubage index, and cement leakage were evaluated in the 2 groups, and the variables with significant differences between the 2 groups were analyzed in Logistic regression analysis.

RESULTS

BMD was significantly lower and the rate of cement leakage was significantly higher in the re-fracture group than in the control group (P<0.05). Significant difference was found in cement distribution index between the 2 groups (P<0.05) but not in age, gender, cement volume or volume-cubage index (P>0.05). Logistic regression analysis indicated that BMD, cement leakage and cement distribution index all significantly affected the occurrence of adjacent vertebral fractures following percutaneous vertebroplasty.

CONCLUSION

A low BMD, cement leakage and a low cement distribution index are all risks factor of adjacent vertebral fracture after percutaneous vertebroplasty.

Elastoplasty as a promising novel technique: Vertebral augmentation with an elastic silicone-based polymer

OBJECTIVE

Percutaneous vertebroplasty with polymethylmethacrylate (PMMA) restores the stiffness and the strength of fractured vertebral bodies, but changes the pattern of the stress transfer. This effect may cause a secondary fracture of the adjacent vertebrae. Elastoplasty has emerged as a new technique to overcome this complication. The aim of this study is to retrospectively evaluate the clinical results of the elastoplasty procedure.

MATERIALS AND METHODS

Thirthy nine patients (9 males, 30 females, 87 spinal levels) were clinically evaluated pre and postoperatively in terms of pain relief, leakage and silicone embolism. The mean age was 67 (range 38-84) years. The mean follow up period was 12,5 months. The patients were evaluated radiologically for the presence of adjacent level fractures postoperatively. Complications were recorded.

RESULTS

The mean VAS score decreased from 7,5 to 3,5 during the last follow-up. Symptomatic silicone pulmonary embolism was not encountered in any patients. Leakage was observed in 5 (13%) cases. There was an adjacent level fracture in 1 case and another fracture which was not at the adjacent level in another one. A hematoma occurred in the needle entry site in a patient with trombocytopenia (<70,000).

CONCLUSIONS

Elastoplasty is a safe, promising technique in the treatment of vertebral compression fractures (VCFs). Symptomatic silicone pulmonary embolism is not observed. The material's stiffness is close to intact vertebrae. Therefore, elastoplasty may be a good viable option in the treatment of VCFs as it cause less complications and can prevent adjacent level fractures.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Gradual Height Decrease of Augmented Vertebrae after Vertebroplasty at the Thoracolumbar Junction

OBJECTIVE

Vertebroplasty is an effective treatment for vertebral compression fracture, but may progress gradual vertebral height decrease in spite of vertebroplasty. Gradual vertebral height decrease also may induce aggravation of kyphotic change without severe pain. The purpose of this study was to evaluate risk factors for gradual vertebral height decrease in the absence of recurrent severe back pain.

METHODS

A retrospective analysis was performed on 44 patients who were diagnosed with a first osteoporotic compression fracture at a single level at the thoracolumbar junction. All patients were taken vertebroplasty. Possible risk factors for gradual vertebral height decrease, such as sex, age, bone mineral density, body mass index, level of compression fracture, volume of injected cement, cement leakage into disc space, and air clefts within fractured vertebrae, were analyzed.

RESULTS

Gradual vertebral height decrease of augmented vertebrae occurred commonly when more than 4 cc of injected cement was used, and when air clefts within fractured vertebrae were seen on admission. In addition, the sagittal Cobb angle more commonly increased during the follow-up period in such cases.

CONCLUSION

Injection of more than 4 cc of cement during vertebroplasty and air cleft within fractured vertebrae on admission induced gradual vertebral height decrease in augmented vertebrae. Thus, longer follow-up will be needed in such cases, even when patients do not complain of recurrent severe back pain.