Using percutaneous parapedicle screw vertebroplasty to treat transpedicle screw loosening.

BACKGROUND: Pedicle screw loosening (PSL) is a postsurgical complication of spinal fusion surgery that can result in morbidity. The aim of this study was to evaluate the efficacy and safety of percutaneous parapedicle screw vertebroplasty (PPSV) for pain reduction and motility improvement in patients with PSL. METHODS: The postsurgical solid inter-body fusion with inter-body bone mass formation of 32 patients who underwent lumbar-sacrum spinal fusion surgery was confirmed with plain films and CT scans. Each patient had one or two screws with symptomatic PSL and was treated with PPSV. All the patients were then followed up for 12 to 24 months. The visual analog scale (VAS) and Roland-Morris Disability Questionnaire (RMDQ) were used to evaluate each patient before the operation, after the operation, and during the follow-up period. RESULTS: A total of 32 patients with a total of 47 screws with PSL were treated with PPSV and experienced different results in terms of pain reduction (with the mean VAS score dropping from 7.97 ± 0.74 to 2.34 ± 1.59, p < 0.001) and motility improvement (with the mean RMDQ score dropping from 16.75 ± 1.84 to 7.21 ± 4.08, p < 0.001). The motility improvement was significantly correlated with pain reduction (r = 0.42, p = 0.018), with the mean follow-up period being 19.3 ± 6.2 months (range: 8-36 months). However, five patients who experienced moderate improvements had eventually received a revision operation after undergoing PPSV. CONCLUSION: The PPSV procedure is effective and safe for the reduction of pain and improvement of life quality in patients with PSL. It can thus be considered as a possible option for the revision of spinal fusion surgery.

Short-term Efficacy of the Percutaneous Vertebroplasty Using a Curved Versus Straight Vertebroplasty Needle in Osteoporotic Vertebral Compression Fractures.

The purpose of this study was to compare the efficacy of the curved puncture approach with 2 conventional approaches in percutaneous vertebroplasty (PVP) for the treatment of single-level osteoporotic vertebral compression fractures. Ninety-six patients with a single-level thoracolumbar vertebral fracture were surgically treated in the authors' department from February 2016 to February 2018. Patients were randomly divided into 3 groups, including 25 patients who had PVP punctured with a curved vertebroplasty needle (group C), 40 patients with unipedicular PVP with a straight vertebroplasty needle (group U), and 31 patients with bipedicular PVP with a straight vertebroplasty needle (group B). The short-term efficacies of PVP using different vertebroplasty needles were compared. Significant differences were tested preoperatively and postoperatively in vertebral body height variation, visual analog scale score, and Oswestry Disability Index in each of the 3 groups (P<.05). There was no significant difference among the groups in terms of Cobb angle correction and bone cement leakage. Group C and group U were superior to group B in terms of operative time and injected cement volume (P<.05). Twenty-four (96.0%) patients in group C and 29 (93.5%) patients in group B had centered cement distribution without significant differences (P>.05), which was superior to group U (P<.05). Curved puncture PVP achieved a satisfactory clinical outcome for osteoporotic vertebral compression fractures, with the advantages of less operative time, less injected cement volume, and more reasonable cement distribution for stabilization of the affected vertebrae. [Orthopedics. 2021;44(1):e131-e138.].

Comparison of a flexible versus rigid bone cement injection system in unilateral percutaneous vertebroplasty.

BACKGROUND: Percutaneous vertebroplasty (PVP) has been demonstrated to be effective in the treatment of acute osteoporotic vertebral fracture (AOVF). However, bilateral puncture takes more time to accept more X-ray irradiation; some scholars apply unilateral puncture PVP, but the cement cannot be symmetrically distributed in the vertebral body, so we use a flexible cement injector that undergoes PVP through the unilateral pedicle puncture. This research aims to compare the clinical results of PVP for AOVF with unilateral pedicle puncture using a straight bone cement injector and a bendable cement injector, determine the value of a bendable cement injector. METHODS: We undertook a retrospective analysis of patients with thoracic and lumbar compression fracture treated with unilateral pedicle puncture percutaneous vertebroplasty from our institution from June 2013 to July 2015. Operation time, radiation exposure, bone cement injection amount, and the incidence of bone cement leakage were recorded on presentation, the cement leakage was measured by X-ray and computed tomography scan. The patients were followed up postoperatively and were assessed mainly with regard to clinical and radiological outcomes. RESULTS: There was no significant difference in the operation time, radiation exposure time and incidence of bone cement leakage between the two groups. There was significant difference in the amount of bone cement injection and the difference between the two groups. There were no significant differences in VAS and the relative height of the vertebral body and local Cobb angle and QUALEFFO between the two groups at 1 week after PVP, significant difference was observed only 12 months after operation. CONCLUSIONS: Application of flexible cement injector is safe and feasible, compared with the application of straight bone cement injector, without prolonging the operative time, radiation exposure time and the incidence of bone cement leakage; it has the advantages of good long-term effect and low incidence of vertebral fracture recurrence.

Unilateral Biportal Endoscopic-Guided Transcorporeal Vertebroplasty with Neural Decompression for Treating a Traumatic Lumbar Fracture of L5.

BACKGROUND: Lumbar burst fractures (complete or incomplete) of L5 have a low incidence, accounting for 1.2% of all spinal burst fractures. Treatment for these fractures remains controversial. Decompression of neural elements and stabilization of the spine to preserve lordosis and avoid kyphotic deformity are recommended when a patient has a neurological deficit and an unstable fracture. Otherwise, the fracture could be managed conservatively. METHODS: We report a detailed step-by-step unilateral biportal endoscopy technique used in a patient with an L5 incomplete burst fracture and neurological deficit. RESULTS: The patient had an acceptable immediate postoperative course; lower back pain and radicular symptoms improved significantly after surgery. CONCLUSIONS: Our unilateral biportal endoscopy technique for L5 incomplete burst fractures offers the capability to perform enough decompression of neural elements and assist other procedure-related maneuvers under direct endoscopic visualization. This technique could be considered another minimally invasive spine surgery option for treating selected patients with L5 incomplete burst fractures.

Vertebral augmentation with spinal implants: third-generation vertebroplasty.

This article is to review the different types of vertebral augmentation implants recently becoming available for the treatment of benign and malignant spinal compression fractures. After a detailed description of the augmentation implants, we review the available clinical data. We will conclude with a summary of the advantages and disadvantages of vertebral implants and how they can affect the future treatment options of compression fractures.

Spinal Tumor Ablation: Indications, Techniques, and Clinical Management.

Percutaneous thermal ablation has proven to be safe and effective in the management of patients with spinal tumors. Such treatment is currently proposed following the decision of a multidisciplinary tumor board to patients with small painful benign tumors such as osteoid osteoma or osteoblastoma, as well as carefully selected patients presenting with spinal metastases. In both scenarios, in order to provide a clinically effective procedure, ablation is often tailored to the specific patients' clinical needs and features of the target tumor. In this review, we present the most common clinical contexts in which spine ablation may be proposed. We scrutinize technical aspects and challenges that may be encountered during the procedure, as well as offering insight on follow-up and expected outcomes.

Vesselplasty using the Mesh-Hold™ bone-filling container for the treatment of pathological vertebral fractures due to osteolytic metastases: A retrospective study.

PURPOSE: To evaluate the clinical benefits and complications of vesselplasty using the Mesh-Hold™ bone-filling container in the treatment of vertebral osteolytic fractures. METHODS: This was a retrospective study of patients with vertebral osteolytic pathological fractures treated by vesselplasty at Sichuan Cancer Hospital between 09/2014 and 01/2018. VAS1 (Visual analog scale) scores and ODI2 (Oswestry disability index) were recorded routinely 1 day preoperative, at 1 day, 1 month, 3 months, 6 months, and 1 year postoperation, and at the last follow-up. V13 (The of bone cement injection volume) and V24 (vertebral body osteolytic volume) were evaluated, and the R5 (ratio) of bone cement filling was obtained according to the V1/V2. RESULTS: Sixty-three patients were included (105 segments with osteolytic fractures). The amount of bone cement for each vertebra was 2.4-5.2 ml (3.1 ± 0.7 ml). The ratio (R) of bone cement filling was not related to pain relief or functional recovery (all P > 0.05).The VAS scores and ODI at different time points after surgery were decreased compared with before surgery (all P < 0.05). The bone cement leakage rate was 16.2 % (17/105). The follow-up was 4-30 months (mean of 13 ± 6 months). Thirty patients had died by the last follow-up, all from their cancer. CONCLUSIONS: The Mesh-Hold™ bone-filling container in the treatment of vertebral fractures induced by osteolytic metastases could reduce pain, improve function, and reduce the bone cement leakage rate in the process of vesselplasty.

Interface Fixation Using Absorbable Screws versus Plate Fixation in Anterior Cervical Corpectomy and Fusion for Two-Level Cervical Spondylotic Myelopathy.

BACKGROUND We compared the clinical and radiographic outcomes between interface fixation using absorbable screws and plate fixation in anterior cervical corpectomy and fusion (ACCF) to evaluate the effectiveness of these 2 fixation methods for the treatment of 2-level cervical spondylotic myelopathy (CSM). MATERIAL AND METHODS From January 2014 to December 2016, a total of 220 patients who received 2-level ACCF were retrospectively collected. Among them, 108 patients were treated with interface fixation using absorbable screws (Group A) and 112 patients underwent plate fixation (Group B). Japanese Orthopedic Association (JOA) score and Neck Disability Index (NDI) score were employed to compare the clinical improvement. Operative time, blood loss, surgical cost, cervical lordosis, complications, and fusion rate were also evaluated. RESULTS The average follow-up time were 35.2±4.5 months in Group A and 35.9±3.9 months in Group B. There was no difference in operative time and blood loss for both groups. The JOA scores and NDI scores were similar in each follow-up (p>0.05 in all). Group A cost an average of 30% less than Group B for the operation. Both groups achieved 100% in the fusion rate with the same conditions in cervical lordosis. Group A (5/108) had a significantly lower complication rate than Group B (17/112) (p<0.05). CONCLUSIONS ACCF with interface fixation using absorbable screws achieved similar clinical outcomes compared to ACCF with plate fixation for 2-level CSM. Moreover, the interface fixation using absorbable screws presented far fewer complications and cost less for the operation.

Risk Factors for Cement Leakage and Adjacent Vertebral Fractures in Kyphoplasty for Osteoporotic Vertebral Fractures.

PURPOSE: Cement leakage and adjacent vertebral fractures are not uncommon after percutaneous augmentation. However, conclusive identification of risk factors for postprocedural complications remains elusive. The anticipation of leakage and successive fractures through the identification of risk factors will help physicians better inform patients of potential complications and establish procedural refinements key to risk reduction. The aim of this retrospective study was to summarize available reports of the risk factors for cement leak and adjacent vertebral fracture in or after kyphoplasty for osteoporotic vertebral compression fractures. METHODS: A total of 102 cases of bilateral percutaneous kyphoplasty (PKP), performed between January 2014 and December 2016, were retrospectively reviewed. Each case surveyed in this review included a minimum 1-year follow-up and data on age, sex, bone mineral density, Visual Analog Scale score, preoperative compression rate, kyphotic angle, treatment time, the volume of cement, and the intactness of the vertebral posterior wall (computed tomography scan) were collected. Pearson χ test and independent samples test were used to determine the relative risk factors of cement leak and adjacent vertebral fracture in patient subsets. RESULTS: Diabetic status and alteration in the Cobb angle after PKP exhibited a statistically significant correlation with the incidence of new adjacent vertebral fracture (group B) (P<0.05). In addition, the integrity of vertebral walls (P=0.001) and the volume of injected cement (P=0.026) significantly boosted the potential risk of cement leakage (P<0.05), although these variables did not associate with the adjacent fracture. Additional examined variables, including age, sex, Visual Analog Scale scores, number of fractures were not significantly associated with leakage or adjacent vertebral fracture risk. CONCLUSIONS: Diabetes and the alteration of the Cobb angle following PKP are factors positively related to the occurrence of postoperative adjacent vertebral fractures. It is also demonstrated that the integrity of vertebral walls and average volumes of injected cement are the possible risk factors of cement leakage while performing the PKP.

Cortical Bone Trajectory Instrumentation with Vertebroplasty for Osteoporotic Thoracolumbar Compression Fracture.

BACKGROUND: Osteoporotic spinal fractures commonly occur in elderly patients with low bone mineral density. In these cases, percutaneous vertebroplasty or percutaneous kyphoplasty can provide significant pain relief and improve mobility. However, studies have reported both the recurrence of vertebral compression fractures at the index level after vertebroplasty and the development of new vertebral fractures at the adjacent level that occur without any additional trauma. Pedicle screw fixation combined with percutaneous vertebroplasty has been proposed as an effective procedure for addressing osteoporotic thoracolumbar fractures. However, in osteoporotic populations, pedicle screws can loosen, pullout, or migrate. Currently, the efficacy of cortical bone trajectory screw fixation for osteoporotic fractures remains unclear. Thus, we assessed the effects of using cortical bone trajectory instrumentation with vertebroplasty on patient outcomes. METHOD: We retrospectively reviewed data from 12 consecutively sampled osteoporotic thoracolumbar fracture patients who underwent cortical bone trajectory instrumentation with vertebroplasty. Patients were enrolled beginning in October 2015 and were followed for >24 months. RESULT: The average age was 74 years, and the average dual-energy x-ray absorptiometry T-score was -3.6. The average visual analog scale pain scores improved from 8 to 2.5 after surgery. The average blood loss was 36.25 mL. All patients regained ambulation and experienced reduced pain post-surgery. No recurrent fractures or instrument failures were recorded during follow-up. CONCLUSIONS: Our findings suggest that cortical bone trajectory instrumentation combined with percutaneous vertebroplasty may be a good option for treating osteoporotic thoracolumbar fractures, as it can prevent recurrent vertebral fractures or related kyphosis in sagittal alignment.

A second puncture and injection technique for treating osteoporotic vertebral compression fractures.

OBJECTIVE: To evaluate the clinical effect of the second puncture and injection technique during a percutaneous vertebroplasty (PVP) procedure. METHODS: Patients treated with a second puncture and injection (group A) or a single puncture and injection (group B) during PVP at our institution during 2010-2017 were reviewed. Vertebral height loss, visual analogue scale (VAS) score, Oswestry disability index (ODI), adjacent vertebral fractures, and cement leakage were compared between the groups. RESULTS: A total of 193 patients were enrolled (86 cases in group A, 107 cases in group B). The follow-up period was 15.64 (12-20) months. The loss of anterior (group A 0.01 ± 0.03; group B 0.14 ± 0.17) and middle (group A 0.13 ± 0.12; group B 0.16 ± 0.11) vertebral height in group B was significantly higher than that in group A (P < 0.05). The VAS score and ODI were also significantly higher in group B than in group A at the final follow-up; the VAS score and ODI in group B were 1.65 ± 0.70 and 14.50 ± 4.16, respectively, and those in group A were 1.00 ± 0.74 and 12.81 ± 4.02, respectively (P < 0.05). Three patients in group A and two in group B experienced adjacent vertebral fractures. Regarding mild, moderate, and severe cement leakage, there were 25 (29%), 5 (5%), and 0 cases, respectively, in group A and 28 (26%), 3 (2.8%), and 1 (0.009%) case, respectively, in group B (P > 0.05). CONCLUSIONS: The second puncture and injection technique may effectively increase the dispersion of cement, thus preventing recompression of the cemented vertebral body, and it does not increase the risk of cement leakage or adjacent vertebral fracture.

Unilateral curved versus bipedicular vertebroplasty in the treatment of osteoporotic vertebral compression fractures.

BACKGROUND: Vertebral compression fracture is one of the most common complications of osteoporosis. In this study an unilateral curved vertebroplasty device was developed, and the safety, effectiveness, and surgical parameters of curved vertebroplasty (CVP) in the treatment of painful osteoporotic vertebral compression fractures was investigated and compared with traditional bipedicular vertebroplasty (BVP). METHODS: We investigated 104 vertebral augmentation procedures performed over 36 months. CVP and BVP procedures were compared for baseline clinical variables, pain relief (Visual Analog Scale, VAS), disability improvement (Oswestry Disability Index, ODI), operation time, number of fluoroscopic images, volume of cement per level, and cement leakage rate for each level treated. Complications and refracture incidence were also recorded in the two groups. RESULTS: The VAS and ODI in both group had no significant difference preoperative (P > 0.05), and a significant postoperative improvement in the VAS scores and ODI was found in both group (P < 0.001). However, the CVP group had significantly lower operation time, number of fluoroscopic images, and cement leakage rate per level than the BVP group (P < 0.05); however, the volumes of cement per level were similar in the two groups (P > 0.05). Neither group had any serious complications. Five and two patients in the BVP group developed refractures at non-adjacent and adjacent levels, respectively, with one patient developing refractures twice; however, none of the patients in the CVP group developed refractures at any level. CONCLUSIONS: Our findings revealed that both CVP and BVP were safe and effective treatments for osteoporotic vertebral compression fractures, and CVP entails a shorter operation time, less exposure to fluoroscopy, and lower rate of cement leakage.

The poly (l-lactid-co-glycolide; PLGA) fiber component of brushite-forming calcium phosphate cement induces the osteogenic differentiation of human adipose tissue-derived stem cells.

A brushite-forming calcium phosphate cement (CPC) was mechanically stabilized by addition of poly (l-lactid-co-glycolide; PLGA) fibers (≤10% w/w). It proved highly biocompatible and its fiber component enhanced bone formation in a sheep lumbar vertebroplasty model. However, possible effects on the osteogenic differentiation of resident mesenchymal stem cells (MSCs) remained unexplored. The present study used a novel approach, simultaneously analyzing the influence of a solid CPC scaffold and its relatively low PLGA proportion (a mimicry of natural bone) on osteogenic, chondrogenic, and adipogenic differentiation, as well as the pluripotency of human adipose tissue-derived mesenchymal stem cells (hASCs). hASCs were cultured on CPC discs with/without PLGA fibers (5% and 10%) in the absence of osteogenic medium for 3, 7, and 14 d. Gene expression of osteogenic markers (Runx2, osterix, alkaline phosphatase, collagen I, osteonectin, osteopontin, osteocalcin), chondrogenic markers (collagen II, Sox9, aggrecan), adipogenic markers (PPARG, Leptin, and FABP4), and pluripotency markers (Nanog, Tert, Rex) was analyzed by RT-PCR. The ability of hASCs to synthesize alkaline phosphatase was also evaluated. Cell number and viability were determined by fluorescein diacetate/propidium iodide staining. Compared to pure CPC, cultivation of hASCs on fiber-reinforced CPC transiently induced the gene expression of Runx2 and osterix (day 3), and long-lastingly augmented the expression of alkaline phosphatase (and its enzyme activity), collagen I, and osteonectin (until day 14). In contrast, augmented expression of all chondrogenic, adipogenic, and pluripotency markers was limited to day 3, followed by significant downregulation. Cultivation of hASCs on fiber-reinforced CPC reduced the cell number, but not the proportion of viable cells (viability > 95%). The PLGA component of fiber-reinforced, brushite-forming CPC supports long-lasting osteogenic differentiation of hASCs, whereas chondrogenesis, adipogenesis, and pluripotency are initially augmented, but subsequently suppressed. In view of parallel animal results, PLGA fibers may represent an interesting clinical target for future improvement of CPC- based bone regeneration.

Therapeutic efficacy of Transpedicular Intracorporeal cement augmentation with short segmental posterior instrumentation in treating osteonecrosis of the vertebral body: a retrospective case series with a minimum 5-year follow-up.

BACKGROUND: Transpedicular intracorporeal cement augmentation (TCA) with short segmental posterior instrumentation (SSPI), which provides an ideal immediate analgesic effect and long-term reconstructive stability, is thought to be a sensible advancement to the operative strategy in treating osteonecrosis of the vertebral body (ONV). However, long-term follow-up studies about the treatment are scarce. METHODS: Forty-six ONV patients (22 males and 24 females, mean age of 62.8 ± 7.11 years) underwent TCA with SSPI were retrospectively analyzed. During follow-up, clinical outcomes, such as the Visual Analogue Scale (VAS) score and the Oswestry Disability Index (ODI) score, were evaluated, as well as radiologic outcomes, such as the average vertebral height and kyphotic angle. RESULTS: A total of 36 patients completed a follow-up period of at least 5 years (mean follow-up period of 67 ± 4.2 months). Among them, seven patients experienced complications, i.e., pneumonia (2/36, 5.56%), screw loosening (2/36, 5.56%), moderate hematoma in the subcutaneous tissue (1/36, 2.78%), and cement leakage (2/36, 5.56%). Compared to the preoperative score, the mean VAS score was significantly reduced 6 months postoperatively (P < 0.05), and it concluded being virtually identical to the preoperative score (P > 0.05). The mean ODI score exhibited a comparable trend. Regarding the radiologic evaluation, the mean kyphotic angle and average vertebral body height were significantly corrected postoperatively (both P < 0.05). However, these radiological parameters were maximally ameliorated during the direct postoperative period and slowly deteriorated over time. CONCLUSION: The present study shows that TCA with SSPI may be only mildly effective for symptom relief and correction of kyphotic deformity during a relatively long follow-up, thus we do not recommend it for ONV.

Percutaneous vertebroplasty with granulated allogeneic bone grafting using screw-view model of navigation for thoracolumbar compressive fracture: A case report.

RATIONALE: The aim of this study was to assess the accuracy of percutaneous puncture needle with screw view model of navigation (SVMN) and the effect of periacetabular vertebroplasty (PVP) with granulated allogeneic bone grafting in thoracolumbar compressive fracture (TCF). PATIENT CONCERNS: A 46-year-old female patient associated with high fall injury showed symptoms characterized by back pain and restricted movement of the right lower extremity. DIAGNOSES: The patient was diagnosed with a TCF, right femoral neck fracture, and lumbar vertebrae hyperosteogeny. INTERVENTIONS: A SVMN was used to guide our puncture needle insertion; and PVP was performed with granulated allogeneic bone grafting in this patient. OUTCOMES: The follow-up lasted for 29 months. It took 2.4 minutes to design the trajectory of puncture needle, 2.1 minutes to implant the puncture needle, and 6.3 minutes to undergone fluoroscopy. Postoperative visual analog scale and Oswestry disability index scores were improved obviously compared with those before the operation. The Cobb angle of fractured vertebrae improved from 9.3° to 7.3° after treatment. The height ratio of fractured vertebrae increased from 79.5% to 90.6% postoperatively. Intraoperative blood loss amounted to 11 ml. No clinical complications were observed, including neurovascular injury and new fracture of adjacent vertebra. LESSONS: Puncture needle placement under the guidance of SVMN is verified as a convenient, safe and reliable method, and PVP with granulated allogeneic bone grafting can effectively restore the height of anterior fractured vertebra, filling the gaps in the fractured vertebrae, and reconstructing the completeness of the fractured vertebrae.

Bracing after percutaneous vertebroplasty for thoracolumbar osteoporotic vertebral compression fractures was not effective.

OBJECTIVE: The objective of this study was to evaluate the effectiveness of bracing after percutaneous vertebroplasty (PVP) for thoracolumbar osteoporotic vertebral compression fractures (OVCF). METHODS: This is a retrospective study where we recruited 138 patients with single-level thoracolumbar OVCF who underwent PVP from January 2018 to March 2018 without bracing after PVP (Group A). The visual analog score (VAS) and vertebral body compression ratio (VCR) were recorded at preoperation, on the second day, at 2 weeks, 1 month, and 6 months after operation. Oswestry Disability Index (ODI) was recorded at preoperation, 2 weeks, 1 month, and 6 months after operation. Propensity score matching identified 138 historical patients (Group B) as controls, who used rigid brace for 3 weeks after the surgery, from January 2017 to December 2017 using six independent variables (preoperation): age, sex, VAS, ODI, bone mineral density, and body mass index. The indicators and complications were compared between the two groups. RESULTS: Compared with preoperation, VAS and VCR were significantly improved (P<0.05) in both groups on the second day after operation. At 2 weeks, 1 month, and 6 months after PVP operation, ODI, VAS, and VCR were all significantly improved than at preoperation (P<0.05). There were no statistical differences between the two groups in VAS and VCR on the second day, at 1 month and 6 months after PVP (P<0.05). There were no significant differences between Groups A and B in ODI at 2 weeks and 6 months after operation (P<0.05) but ODI for Group B at 1 month after operation was significantly higher than Group A (P<0.05). Eleven cases in Group A and 13 cases in Group B had poor pain relief on the second day after operation, and there were no significant differences in VAS and ODI between the two subgroups at 2 weeks, 1 month, and 6 months after PVP. There were no significant differences in the collapse and refracture rates between the two groups. CONCLUSION: In summary, in terms of quality of life and complications after operation, postoperative bracing did not result in improved outcomes. Presence or absence of bracing did not relieve postoperative residual pain. In contrast, bracing for 3 weeks after operation reduced the quality of life in the short term.

Republished: Parapedicular vertebral augmentation with polymethylmetacrylate for pedicle screw loosening.

A 71-year-old man who had a L1/S1 posterior fusion revision surgery complained of increasing back pain 5 weeks after the open surgical procedure. The pain was initially estimated at 9/10 on the visual analog scale (VAS) and thought to be related to a right-sided L2 screw loosening. A right parapedicular vertebroplasty was performed and polymethylmethacrylate cement was instilled around the right pedicle screw, filling the anterior two-thirds of the vertebral body. On postvertebroplasty day 1, the patient had significant improvement in his low back pain. The pain further decreased at 1 and 3 months after the intervention (2/10 on the VAS). Vertebroplasty is a minimally invasive, accessible, effective, and long lasting treatment for compression fractures. We believe that this technique could also be indicated to treat pain related to low grade screw loosening in properly selected patients.

Stent-screw-assisted internal fixation: the SAIF technique to augment severe osteoporotic and neoplastic vertebral body fractures.

OBJECTIVES: To describe a new technique to obtain minimally invasive but efficient vertebral body (VB) reconstruction, augmentation, and stabilization in severe osteoporotic and neoplastic fractures, combining two pre-existing procedures. The implant of vertebral body stents (VBS) is followed by insertion of percutaneous, fenestrated, cement-augmented pedicular screws that act as anchors to the posterior elements for the cement/stent complex. The screws reduce the risk of stent mobilization in a non-intact VB cortical shell and bridge middle column and pedicular fractures. This procedure results in a 360° non-fusion form of vertebral internal fixation that may empower vertebral augmentation and potentially avoid corpectomy in challenging fractures. PROCEDURE DETAILS: This report provides step-by-step procedural details, rationale, and proposed indications for this procedure. The procedure is entirely percutaneous under fluoroscopic guidance. Through transpedicular trocars the VBS are inserted, balloon-expanded and implanted in the VB. Over k-wire exchange the transpedicular screws are inserted inside the lumen of the stents and cement is injected through the screws to augment the stents and fuse the screws to the stents. APPLICATIONS: This technique may find appropriate applications for the most severe osteoporotic fractures with large clefts, high-degree fragmentation and collapse, middle column and pedicular involvement, and in extensive neoplastic lytic lesions. CONCLUSIONS: Stent-Screw-Assisted Internal Fixation (SAIF) might represent a minimally invasive option to obtain VB reconstruction and restoration of axial load capability in severe osteoporotic and neoplastic fractures, potentially obviating the need for more invasive surgical interventions in situations that would pose significant challenges to standard vertebroplasty or balloon kyphoplasty.