[Percutaneous vertebroplasty]

Tuberculous spondylitis after percutaneous vertebroplasty: A case series of 9 cases

Background

Percutaneous vertebroplasty has become the treatment of choice for compression fractures. Although the incidence is low, infection after vertebroplasty is a serious complication. The pathogens most often responsible for infection are bacteria. Meanwhile, mycobacterium tuberculosis-induced infection is extremely rare. In this study, we reported our treatment experience with 9 cases of tuberculous spondylitis after vertebroplasty.

Methods

Between January 2001 and December 2015, 5749 patients underwent vertebroplasty or kyphoplasty in our department. Nine cases developed tuberculous spondylitis after vertebroplasty (0.16%). Data on clinical history, laboratory examinations, image, treatment and outcomes were examined.

Results

One male and 8 female patients with a mean age of 75.1 years developed tuberculous spondylitis after vertebroplasty. 5 patients had a history of pulmonary tuberculosis (TB). Revision surgeries were performed from 5 days to 1124 days after vertebroplasty. Seven patients underwent anterior debridement and fusion with or without posterior instrumentation, and 2 cases received posterior decompression and instrumentation only. After operation, the diagnosis of tuberculous spondylitis was confirmed by TB polymerase chain reaction (TB-PCR) or mycobacteria culture. Mean follow-up period after revision surgery was 36.8 months. At the end of follow-up, 1 patient with paraplegia had passed away, 2 needed a wheel chair, 4 required a walker and 2 were able to walk unassisted.

Conclusions

Vertebroplasty is a minimally invasive procedure but still retains some possibility of complications, including TB infection. Patients with a history of pulmonary TB or any elevation of infection parameters should be reviewed carefully to avoid infective complications.

Prognostic indicators for papillary thyroid carcinoma

Differentiated thyroid cancer (DTC) includes more than 90% of all thyroid carcinoma and its incidence is growing, mainly due to an increase in the incidence of papillary thyroid cancer (PTC) for the widespread use of neck ultrasonography. Areas covered: Several prognostic factors should be considered during the management of PTC in order to provide the most effective treatment. The most important prognostic factors in PTC include personal and pathological features such as patient's age, gender, hystotype, tumor size, extrathyroidal extension, lymph node involvement, presence of local or distant metastases and molecular analyses. We performed a search in the PubMed database for studies published in English since 1960 using the terms: 'thyroid cancer', 'prognostic factors', 'age', 'gender', 'hystotype', 'tumor size', 'extrathyroidal extension', 'lymph node', 'metastases' and 'molecular analyses'. Expert commentary: Prognostic factors can guide clinicians during the treatment and follow-up of DTC patients, but it is now evident that the risk of recurrence or death must be evaluated periodically, on the basis of individual risk, according to the response to initial therapy or the subsequent therapy required during follow-up.

Spinal tuberculosis of the lumbar spine after percutaneous vertebral augmentation (vertebroplasty or kyphoplasty)

BACKGROUND CONTEXT

Spinal tuberculosis occurring after percutaneous vertebral augmentation has rarely been described. To date, only two such cases have been documented in the literature. Vertebral augmentation may reactivate a quiescent tuberculous lesion and promote the infective process in elderly patients with or without immunosuppression, thereby resulting in poor outcomes.

PURPOSE

The purposes of this study were to present two cases in which spinal tuberculosis occurred after vertebroplasty or kyphoplasty, to highlight the clinical features and need for early diagnosis of this pathology, and to postulate probable reasons for this association.

STUDY DESIGN

This study is based on a clinical case series and literature review.

METHODS

In this report, we review the clinical histories of two old women undergoing vertebral augmentation with subsequent spinal tuberculosis.

RESULTS

The first patient responded favorably to conservative treatment with multidrug antitubercular therapy and spinal braces. The second patient underwent surgical debridement through a posterior approach alone, without instrumentation, combined with adjuvant chemotherapy. By 1 year after treatment, both patients had experienced almost complete recovery and continued to be seen for follow-up visits.

CONCLUSIONS

Suspicion should be high, and magnetic resonance imaging is warranted in cases with deteriorating clinical symptoms and signs of acute infection after vertebral augmentation. We propose obtaining exhaustive microbiologic and histologic evidence via needle biopsy or open surgery in a timely fashion to establish an accurate diagnosis because tubercular spondylitis occurring in such a situation may progress rapidly.

Robot-assisted vertebral body augmentation: a radiation reduction tool

STUDY DESIGN

Retrospective.

OBJECTIVE

To assess radiation exposure time during robot-guided vertebral body augmentation compared with other published findings.

SUMMARY OF BACKGROUND DATA

Rising incidence of vertebral compression fractures in the aging population result in widespread use of vertebral body cement augmentation with significant radiation exposure to the surgeon, operating room staff, and patient. Radiation exposure leads to higher cancer rates among orthopedic and spine surgeons and patients.

METHODS

Thirty-three patients with 60 vertebral compression fractures underwent robot-guided vertebral body augmentation performed by 2 surgeons simultaneously injecting cement at 2 levels under pulsed fluoroscopy. The age of patients was in the range from 29 to 92 (mean, 67 yr). One to 6 vertebrae were augmented per case (average 2). Twenty-five patients had osteoporotic fractures and 8 had pathological fractures. Robotic guidance data included execution rate, accuracy of guidance, total surgical time, and time required for robotic guidance. Radiation-related data included the average preoperative computed tomographic effective dose, radiation time for calibration, registration, placement of Kirschner wires, and total procedure radiation time. Radiation time per level and surgeon's exposure were calculated.

RESULTS

Kyphoplasty was performed in 15 patients (1 sacroplasty), vertebroplasty in 13, and intravertebral expanding implants in 5. The average preoperative computed tomographic effective dose was 50 mSv (18-81). Average operative time was 118 minutes (49-350). Mean robotic guidance took 36 minutes. Average operative radiation time was 46.1 seconds per level (33-160). Average exposure time of the surgeons and the operating room staff per augmented level was 37.6 seconds. The execution rate was 99%, with an accuracy of 99%. Two complications (hemothorax and superficial wound infection) occurred.

CONCLUSION

The radiation exposure of the surgeon and the operating room staff in a series of robot-assisted vertebral body augmentation was 74% lower than published results on fluoroscopy guidance and approximately 50% lower than the literature on navigated augmentation.

LEVEL OF EVIDENCE

4.

Infection after vertebroplasty or kyphoplasty. A series of nine cases and review of literature

BACKGROUND CONTEXT

Percutaneous augmentation with bone cement is a widely accepted modality of treatment for thoracic and lumbar vertebral osteoporotic fractures. Infection after vertebroplasty or kyphoplasty is a serious, yet, rarely reported complication.

PURPOSE

To present a case series with a long-term follow-up of spinal infection after vertebroplasty/kyphoplasty with analysis of preoperative condition, risk factors, diagnostic findings, time before reoperation, causative organism, treatment, and outcome.

STUDY DESIGN

A retrospective, uncontrolled clinical case series in a single institution.

PATIENT SAMPLE

Between January 1997 and June 2012, 1,307 patients underwent percutaneous vertebroplasty or kyphoplasty. Six cases had postoperative infection (0.46%) and three additional cases were referred from other institutions for salvage treatment.

OUTCOME MEASURES

Perioperative assessment included visual analog scale, clinical, laboratory, and imaging findings, and activities of daily living at the end of the follow-up.

METHODS

Nine patients were included: six females and three males (mean age 73.8 years). Comorbidities were found in all patients. Kyphoplasty had been done in five patients and vertebroplasty in four.

RESULTS

The interval between augmentation and revision surgery ranged from 10 to 395 days with a mean of 118.4 days. Three cases with early infection presented within 1 month. Infection parameters were high in all patients at readmission. All patients were treated surgically except one case who died before the planned revision surgery. In all cases, debridement and corpectomy were done through anterior approaches combined with posterior instrumentation. The most common causative organism was Staphylococcus aureus in three cases. Mean follow-up period after the revision surgery was 26.68 months, excluding two patients who died early in the follow-up (within 4 months). This amounts to a mortality rate of 33.3% perioperatively. At the end of follow-up, two patients had unrestricted activities and one patient required a walker. Of three paraparetic patients, two improved functionally and could walk unassisted and one improved but still used a wheelchair.

CONCLUSIONS

Although vertebroplasty and kyphoplasty are minimally invasive interventions, postoperative infection can develop into life-threatening complications. This should be accounted for, in decision making in the elderly age group most commonly affected by osteoporotic fractures and especially in suspicious and high-risk immune-compromised patients.

The major complications of transpedicular vertebroplasty

OBJECT

Vertebroplasty is a well-known technique used to treat pain associated with vertebral compression fractures. Despite a success rate of up to 90% in different series, the procedure is often associated with major complications such as cord and root compression, epidural and subdural hematomas (SDHs), and pulmonary emboli, as well as other minor complications. In this study, the authors discuss the major complications of transpedicular vertebroplasty and their clinical implications during the postoperative course.

METHODS

Vertebroplasty was performed in 12 vertebrae of 7 patients. Five patients had osteoporotic compression fractures, 1 had tumoral compression fractures, and 1 had a traumatic fracture. Two patients had foraminal leakage, 1 had epidural leakage, 1 had subdural cement leakage, 2 had a spinal SDH, and the last had a split fracture after the procedure.

RESULTS

Three patients had paraparesis (2 had SDHs and 1 had epidural cement leakage), 3 had root symptoms, and 1 had lower back pain. Two of the 3 patients with paraparesis recovered after evacuation of the SDH and subdural cement; however, 1 patient with paraparesis did not recover after epidural cement leakage, despite cement evacuation. Two patients with foraminal leakage and 1 with subdural cement leakage had root symptoms and recovered after evacuation and conservative treatment. The patient with the split fracture had no neurological symptoms and recovered with conservative treatment.

CONCLUSIONS

Transpedicular vertebroplasty may have major complications, such as a spinal SDH and/or cement leakage into the epidural and subdural spaces, even when performed by experienced spinal surgeons. Early diagnosis with CT and intervention may prevent worsening of these complications.

Infected vertebroplasty: case report and review of literature

STUDY DESIGN

Case report.

OBJECTIVES

To describe a case of infected vertebroplasty and to demonstrate the importance of polymerase chain reaction (PCR) in the diagnosis of such infections.

SUMMARY OF BACKGROUND DATA

Infection of the vertebroplasty site is an uncommon complication of vertebroplasty. Only 4 cases have been reported in the literature so far, and an organism could be identified in only 2 of those cases. To our knowledge, the use of PCR to diagnose infection in these cases has not been reported before.

METHODS

Vertebroplasty, laminectomy, radiology, fluid aspiration, microbial culture, and 16S RNA PCR.

RESULTS

A 73-year-old diabetic woman underwent vertebroplasty for L2 and L3 vertebral compression fractures followed by L4-L5 laminectomy for spinal stenosis. Three months later, she had an L1 fracture that was augmented with vertebroplasty. Six months later, she presented with incapacitating low back pain. There was a fluid-filled cavity surrounding the polymethylmethacrylate in the L1 and L2 vertebral bodies. The fluid had 95,000 white blood cells with 96% neutrophils, grew nothing on culture, but had 100% homology with Streptococcus agalactiae on 16S ribosomal nucleic acid analysis.

CONCLUSIONS

We report a case of infected vertebroplasty with atypical radiologic findings of vertebral infection. To our knowledge, this is the third reported case where an organism could be isolated for these infections and the first time PCR has been used to diagnose such an infection.

Infected vertebroplasty due to uncommon bacteria solved surgically: a rare and threatening life complication of a common procedure: report of a case and a review of the literature

STUDY DESIGN

Case report.

OBJECTIVE

The aim of this work is to describe a case of infected vertebroplasty due to uncommon bacteria solved surgically with 2 years of follow-up and to discuss 6 other cases found in literature.

SUMMARY OF BACKGROUND DATA

Vertebroplasty is a well-known and useful technique for the treatment of painful osteoporotic vertebral fractures. Complications, such as cord or root compression or pulmonary embolisms, are infrequent and are mainly related with the frequent escape of cement throughout the vertebral veins. Infection is even more rare, but when it occurs is difficult to manage and can be a life-threatening complication.

METHODS

A 63-year-old-man had a spondylitis of L2 after vertebroplasty. The patient was initially managed with antibiotics without clinical improvement. Surgical treatment by anterior debridement and anterior and posterior stabilization was done. The bacteria isolated from the intraoperative cultures were Serratia marcescens, Stenotrophomonas maltophilia, and Burkholderia cepacia. After surgery, the patient was treated with antibiotics for 3 month.

RESULTS

After 2 years of follow-up, the patient was free of pain, without signs of infection, and a correct fusion was achieved.

CONCLUSION

When facing an infected vertebroplasty, initial conservative treatment with needle biopsy culture and antibiotic administration are a rational option to start. If this treatment fails, surgical debridement is then indicated in order to remove the infected tissue and the acrylic cement and to stabilize the spine. Although this can be an effective treatment, it could be a difficult and hazardous surgical procedure.

Infected vertebroplasty requiring 360 degrees spinal reconstruction: long-term follow-up review. Report of two cases

Transpedicular vertebroplasty has been established as a safe and effective treatment of thoracic and lumbar compression fractures. Complications are rare, and infectious complications requiring surgical management have only been reported once in the literature. The authors present two cases of infectious complications requiring surgical management. They emphasize that systemic infection is a contraindication to the performance of vertebroplasty. The serious nature of these infections, their surgical management, and strategies for avoiding them are discussed.

Radiographic and histologic findings of vertebral augmentation using polymethylmethacrylate in the primate spine: percutaneous vertebroplasty versus kyphoplasty

STUDY DESIGN

Animal study.

OBJECTIVES

To investigate the gross behavior and the histologic effect(s) of polymethylmethacrylate (PMMA) in primate vertebral bodies after percutaneous vertebroplasty and kyphoplasty.

SUMMARY OF BACKGROUND DATA

PMMA is known to induce thermal osteonecrosis in exposed bone during tumor surgery and total joint arthroplasty, and barium sulfate as well as PMMA are known to induce a foreign body reaction, but the effects of PMMA on vertebral cancellous bone have not been well documented. Furthermore, little is known about the mechanisms of cement extravasation that occasionally occur during these procedures. Lastly, it is not known if differences exist between vertebroplasty and kyphoplasty with regards to the above occurrences.

METHODS

Six living, elderly, female baboons were used in this study. Seven vertebrae from T12 to L6 were investigated in each animal. Two levels underwent vertebroplasty, two underwent kyphoplasty, and one underwent cavity creation only without cement augmentation in each animal. Three animals were killed at 24 hours and three at 26 weeks after surgery. The specimens were examined macroscopically for cement migration, and histologically for evidence of thermal necrosis, foreign body reaction, cement migration, and intravascular extravasation.

RESULTS

Small zones of osteonecrosis were observed histologically at the bone-cement interface in only two kyphoplasty (2 of 6) and two vertebroplasty specimens (2 of 5) at 26 weeks after surgery. All of these necrotic segments of bone were associated with new bone formation. Foreign body reactions were observed in all specimens at 26 weeks after surgery, yet none of them was associated with bone resorption. The incidence of cement leak into the spinal canal and adjacent soft tissues was 6 of 11 and 4 of 11 in vertebroplasty specimens and 5 of 12 and 3 of 12 in kyphoplasty specimens, respectively. There was no statistical difference in the incidence of cement leakage into the spinal canal (P = 0.54) and adjacent soft tissues (P = 0.55) between vertebroplasty and kyphoplasty specimens. The incidence of intravascular cement was significantly greater in vertebroplasty (11 of 12, 91%) than in kyphoplasty (5 of 12, 42%) (P = 0.013).

CONCLUSIONS

PMMA caused relatively little necrotic exothermal effect. The presence of PMMA with barium sulfate induces a mild foreign body reaction. The use of a balloon tamp creates a void by displacing pieces of bone, which may result in a lower incidence of intravascular cement leak.

Serious pyogenic spondylitis following vertebroplasty--a case report

STUDY DESIGN

The aim of this case report is to examine the problem of serious pyogenic spondylitis that may follow vertebroplasty.

OBJECTIVES

To report 1 case of serious pyogenic spondylitis caused by percutaneous vertebroplasty with polymethyl methacrylate.

SUMMARY OF BACKGROUND DATA

Serious pyogenic spondylitis caused by percutaneous vertebroplasty with polymethyl methacrylate is a rare complication. We herein report a case of pyogenic spondylitis that occurred after the patient had undergone vertebroplasty.

METHODS

A 78-year-old woman with a T12 osteoporotic compression fracture, and without a magnetic resonance imaging sign of infection, underwent percutaneous vertebroplasty using polymethyl methacrylate without complication. RESULTS.: About 1 month after the operation, the patient was readmitted because of severe backache, and the diagnosis of pyogenic spondylitis was made using radiograph and magnetic resonance imaging. Anterior inter-body fusion with a strut bone graft after debridement and posterior instrumentation were then performed.

CONCLUSIONS

Vertebroplasty should proceed under sterile conditions. Excluding the possibility of spinal infection before surgery and a detailed evaluation assuring that the patient is without systemic infectious disease before the vertebroplasty procedure is crucial.

Survival and therapeutic modalities in patients with bone metastases of differentiated thyroid carcinomas

Data for patients with bone metastases (BMs) of differentiated thyroid carcinoma (DTC) were retrospectively studied to identify factors associated with survival. We especially studied the impact of therapies. Among the 1977 patients followed for DTC in our department from 1958 to 1999, 109 (77 females and 32 males; age range, 20--87 yr) presented BMS: All patients except 1 underwent total thyroidectomy, followed by radioiodine therapy (> or =3.7 gigabecquerels) in 95 cases. Survival rates at 5 and 10 yr were 41% and 15%, respectively. Univariate analyses indicated that a young age at BM discovery (P < 0.005) and the discovery of BM as a revealing symptom of DTC (P < 0.05) were features significantly associated with improved survival as well as radioiodine therapy (P < 10(-4)) and BM complete surgery (P < 0.02). Using multivariate analysis, the detection of BMs as a revealing symptom of thyroid carcinoma (P < 0.0005), the absence of metastasis appearance in other organs than bones during the follow-up (P < 0.03), the cumulative dose of radioiodine therapy (P < 0.0001), and complete BM surgery in young patients (P < 0.04) appeared as independent prognostic features associated with an improved survival.

The strengthening effect of percutaneous vertebroplasty

AIM

To examine whether single-needle vertebroplasty is effective in strengthening vertebrae.

MATERIALS AND METHODS

Four adjacent intact lumbar vertebrae were removed from each of nine adult post-mortem subjects. One or two vertebra of each set was injected with low viscosity acrylic bone cement using a single-track posterolateral approach. Vertebral strength was measured during constant rate axial compression.

RESULTS

Single-needle injection delivered different quantities of cement (1-8 ml) in an asymmetric distribution. Injected vertebrae were stronger than controls in 10 out of 12 cases (P < 0.01), suggesting that cement injection increases the load needed to cause initial vertebral fracture. Compression was continued past the point of initial failure, to simulate progressive vertebral collapse. Injected specimens were more resistant to deformation than control specimens (P < 0.05), most of which initially deformed with little increase in load.

CONCLUSION

Single-track injection of bone cement appeared to strengthen vertebrae against both initial failure and subsequent collapse. The magnitude of strength increase from vertebroplasty was variable, and did not correlate with the volume of cement injected. Further investigation is needed to optimize the technique.Gishen, P. (2000). Clinical Radiology55, 471-476.

The use of an injectable, biodegradable calcium phosphate bone substitute for the prophylactic augmentation of osteoporotic vertebrae and the management of vertebral compression fractures

STUDY DESIGN

A biomechanical study comparing two materials for augmentation of osteoporotic vertebral bodies and vertebral bodies after compression fracture.

OBJECTIVES

To compare an injected, biodegradable calcium phosphate bone substitute with injected polymethylmethacrylate bone cement for strengthening osteoporotic vertebral bodies and improving the integrity of vertebral compression fractures.

SUMMARY OF BACKGROUND DATA

Injection of polymethylmethacrylate bone cement into fractured vertebral bodies has been used clinically. However, there is concern about thermal damage to the neural elements during polymerization of the polymethylmethacrylate bone cement as well as its negative effects on bone remodeling. Biodegradable calcium phosphate bone substitutes have been studied for enhancement of fixation in fractured vertebrae.

METHODS

Forty fresh osteoporotic thoracolumbar vertebrae were used for two separate parts of this study: 1) injection into osteoporotic vertebrae: intact control (n = 8), calcium phosphate (n = 8), and polymethylmethacrylate bone cement (n = 8) groups. Each specimen then was loaded in anterior compression until failure; 2) injection into postfractured vertebrae: calcium phosphate (n = 8) and polymethylmethacrylate bone cement (n = 8) groups. Before and after injection, the specimens were radiographed in the lateral projection to determine changes in vertebral body height and then loaded to failure in anterior bending.

RESULTS

For intact osteoporotic vertebrae, the average fracture strength was 527 +/- 43 N (stiffness, 84 +/- 11 N/mm), 1063 +/- 127 N (stiffness, 157 +/- 21 N/mm) for the group injected with calcium phosphate, and 1036 +/- 100 N (stiffness, 156 +/- 8 N/mm) for the group injected with polymethylmethacrylate bone cement. The fracture strength and stiffness in the calcium phosphate bone substitute group and those in the polymethylmethacrylate bone cement group were similar and significantly stronger than those in intact control group (P < 0.05). For the compression fracture study, anterior vertebral height was increased 58.5 +/- 4.6% in the group injected with calcium phosphate and 58.0 +/- 6.5% in the group injected with polymethylmethacrylate bone cement as compared with preinjection fracture heights. No significant difference between the two groups was found in anterior vertebral height, fracture strength, or stiffness.

CONCLUSION

This study demonstrated that the injection of a biodegradable calcium phosphate bone substitute to strengthen osteoporotic vertebral bodies or improve vertebral compression fractures might provide an alternative to the use of polymethylmethacrylate bone cement.

Future directions. Augmentation of osteoporotic vertebral bodies

Because current medical and surgical treatments of vertebral body fractures are less than adequate, there is a need for interventions that decrease the likelihood of occurrence of these fractures and improve the treatment options once they have occurred. One such broad category of intervention involves the fortification or augmentation of the vertebral bodies. In addition to prophylactically stabilizing osteoporotic vertebral bodies at risk for fracture, augmentation of vertebral bodies that have already fractured may prove to be useful by reducing pain, improving function, and preventing further collapse and deformity. Vertebral body augmentation can also be used as an adjunct to fixation of internal hardware--for example, pedicle screws-in osteoporotic spines. A number of products are now available or are in clinical trials. The most promising products are injectable materials-polymethylmethacrylate or mineral bone cement. The early clinical results using polymethylmethacrylate in percutaneous vertebroplasty for fractured vertebral bodies and the results in vitro using an injectable mineral cement for vertebral body fortification are encouraging. Although the principle of vertebral body augmentation remains encouraging, data to support the widespread use of these techniques remain sparse, and the indications for their use should be more clearly defined.