Cement Extravasation Research Articles

Vertebroplasty Injections Using High Viscosity Cement: a Cadaveric Study

Introduction Vertebral compression fracture (VCF) is a unique type of fractures involving the body of vertebrae. It is associated with a significant decline in functionality and poor quality of life. Osteoporosis, or decreased bone density, is one of the leading causes of VCF. It is commonly seen amongst elderly, especially in post-menopausal women. Vertebroplasty (VP) is a minimally invasive percutaneous technique that involves injecting cement into a pathologic vertebral body, with the aim of pain relief and deformity correction. It is considered the best next line of management when conservative management fails to control symptoms. Although considered minimally invasive, VP has ~1 to 5% risk of clinically evident complications. Where, cement extravasation is the most commonly reported in the literature. Cement viscosity is considered the single most important predictor of the risk of extravasation. Unfortunately, injecting high viscosity cement is difficult to utilize in real practice. We invented a new device capable of injecting high viscosity with ease and at a distance to avoid radiation. The aim of this study is to confirm the efficacy and safety of the new device on cadaveric vertebrae. Materials and Methods For this prospective case-control cohort study, 126 osteoporotic vertebral bodies were harvested form 14 fresh whole human cadavers. DEXA scan and simple X-rays were performed on all specimens to confirm the diagnosis of osteoporosis, and to rule out any pre-existing fractures. A total of 80 vertebral were included in the study. Computer-randomization software was used to allocate specimens over two main groups, Conventional VP and New Device. Both groups were further subdivided into two subgroups, High-Viscosity and Low-Viscosity. A custom device was used on each vertebra to induce a compression fracture. All augmentations were done following the same method commonly practiced in clinical treatment. X-ray radiographs were used to measure and compare cement distribution within the body between groups. Results Injecting high viscosity cement was associated with a lower leakage volume compared with low viscosity cement, with a mean of 0.06cc for the Conventional VP and 0.08cc with the New Device. High viscosity cement was associated with no leakage into the spinal canal. It was also associated with a low incidence of vascular extravasation ( p < 0.001). The mean volume of cement leakage in the low viscosity group was 0.23cc and 0.15cc, for the Conventional VP and New Device respectively. In both groups, the most common site for leakage was the vertebral end plate, which was exhibited more in the low viscosity group (71.5%) compared with the high viscosity group (42.5%). The preset target amount of cement to be injected was reached in 99% of the time when injecting high viscosity cement with the New Device, compared with 62% using the Conventional VP. In both groups, there was no correlation between the amount of cement injected and the amount of leakage. Conclusion The new device is capable of injecting high viscosity cement easily, with a lower incidence of cement leakage. It also minimized the risk of radiation exposure to the surgeon.

The Experience of Eggshell Technique during Kyphoplasty to Prevent Cement Leakage in Treatment of Osteoporotic Vertebral Fracture

Introduction Osteoporosis is the big problem in the aging human. Among these osteoporotic related fractures, vertebral compression commonly is the main one. Pain and disability pose major problems in these patients. To restore the vertebral height for driving physical stiffness, and loading bearing toward normal limited and control the pain, kyphoplasty with variable filling materials (PMMA, CPC etc.) have been used for the treatment. For decreasing the rate of PMMA leakage in various wall injuries in vertebral compression fracture, we performed kyphoplasty with modified eggshell technique in different characteristics of vertebral wall. Material and Methods Twenty-four symptomatic vertebral fractures were enrolled. Visual Analogue Scale, the Oswestry Disability Index and Vertebral Wall Injury Score were assessed. The vertebral height loss and changes of kyphotic angle were also recorded by plain X-ray. Three-dimensional CT will be arranged for evaluating the condition of deficiency vertebral wall and central body collapse if need. After creating cavity by percutaneous bipedicular balloon device, PMMA was injected into weak wall site according the pre-operative evaluation or intra-operative finding. The balloon was once again introduced into the created cavity and inflated to achieve the PMMA shield (regional egg-shell method). Then the PMMA or other materials as CPC materials will be continuously to be fill into the left space. Outcome, fill materials leakage condition, X-ray and CT were reviewed postoperatively. Results Symptomatic cement extravasation related complications or leakage on X-ray were not observed in follow up. Only one adjacent compression fracture was happened in one month. Improvement in vertebral height and the mean kyphotic angle was also noted. The mean VAS and ODI decreased significantly from pre-operation to post-operation ( p < 0.05). The Vertebral Wall Injury Score reviews also told us the eggshell technique is fit for multiple conditions of wall injury Conclusion It's always concerned for the leakage of PMMA during spine surgery. There are many options of new implant for decreasing the rate of leakage. Greene introduces the eggshell technique in 2007, they used the eggshell idea to cover the possible leakage site. They had only 7 patients and those possible cortical defects were noted over superior endplate or lateral wall in their paper. According to our experiences in kyphoplasty with this regional eggshell technique in our 24 patients with various wall injuries. The technique is a safe and significantly functional works for decreasing the leakage of PMMA in various wall injury conditions with experienced surgery operator.

Cardiac Perforation Caused by Cement Embolus After Total Hip Replacement

A 77-year-old woman was transferred to our hospital with persistent chest pain. She had no previous history of coronary heart disease. Two months earlier, she had undergone a complication-free hip replacement surgery with a cemented prosthesis. On admission, she was nearly asymptomatic, but because of elevated cardiac troponin and ST-segment elevation in the inferior and lateral leads, a coronary angiography was performed, which showed normal coronary arteries. However, fluoroscopy revealed a thin, opaque structure apparently overlying the heart. After 2 hours of observation, signs and symptoms of pericarditis were noted, and shortly thereafter, worsening ensued with progression to cardiac tamponade. After percutaneous evacuation of 250 mL blood from the pericardial cavity, her clinical condition normalized. A computed tomography scan was performed …

Effect of the Location of Endplate Cement Extravasation on Adjacent Level Fracture in Osteoporotic Patients Undergoing Vertebroplasty and Kyphoplasty

Background: The most widely researched risk/complication following vertebroplasty (VP) or kyphoplasty (KP) is that of adjacent level fracture (ALF). Current literature results regarding the effect of intradiscal extravasation of cement on the risk of ALF is conflicting with about half of the studies concluding there is no added risk with endplate extravasation and half of the studies reporting opposite conclusions. Objective: The purpose of the study is to further stratify the data to determine whether specifically the location and extent of endplate cement extravasation more strongly affect ALF risk in osteoporotic patients following either VP or balloon KP. Study Design: Retrospective cohort study. Setting: University teaching hospital Methods: One hundred and fifty-six cemented levels in 80 patients, treated at a single center between 2008 and 2012 were reviewed. Age, gender, T-score, body mass index, and osteoporosis type (primary or secondary) were recorded. An ALF was defined as a fracture: 1) in a non-cemented vertebra; 2) adjacent to a cemented level; and 3) not due to trauma or malignancy. Location of the cement extravasation (anterior, middle, or posterior third of the vertebral body) and extravasation extent (percentage of the intervertebral disc height occupied by the bolus) were measured. A logistic modeling strategy permitted examining the association between the location and extent of extravasation and the odds of ALF. Results: ALF occurred in 14 of the 52 patients (27%) and 20 of the 98 levels (20.4%) remaining after exclusions. Odds of ALF were 5.9 times higher (95% CI: 1.6 to 21.2, P = 0.008) with extravasation when compared to no leakage. Odds of ALF in a given patient were 22.6 times higher (95% CI: 3.0 to 170.9, P = 0.003) with anterior extravasation when compared to no leakage. Leakage in the middle or posterior thirds and extent of extravasation were not associated with ALF. Limitations: Limitations of the study include the retrospective study design and small sample size as well as the retrospective implementation of follow-up criteria posing risk of selection bias. Conclusions: Cement endplate extravasation isolated to the anterior third of the vertebral body is associated with is significantly higher odds of ALF after VP or KP in patients with osteoporosis. Key words: Adjacent vertebral fracture, intradiscal leak, osteoporotic compression

Two novel high performing composite PMMA-CaP cements for vertebroplasty: An ex vivo animal study

There is a growing body of the literature on new cement formulations that address the shortcomings of PMMA bone cements approved for use in vertebroplasty (VP) and balloon kyphoplasty (BKP). The present study is a contribution to these efforts by further characterization of two pre-mixed CaP filler-reinforced PMMA bone cements intended for VP; namely, PMMA-HA and PMMA-brushite cements. Each of these cements showed acceptable levels of various properties determined in porcine vertebral bodies. These properties included radiographic contrast, maximum exotherm temperature setting time, cement extravasation, stiffness change after fatigue loading, change of VB height after fracture following fatigue loading, and interdigitation. Each property value was comparable to or better than that for a PMMA bone cement approved for use in BKP. Thus, the results for the composite bone cements are promising.

Radiofrequency ablation and vertebral augmentation for palliation of painful spinal metastases.

Radiofrequency ablation (RFA) and vertebral augmentation is an emerging combination therapy for painful osseous metastases that cannot be or are incompletely palliated with radiation therapy. Herein, we report our experience performing RFA and vertebral augmentation of spinal metastases for pain palliation. Institutional review board approval was obtained to retrospectively review our tumor ablation database for all patients who underwent RFA of osseous metastases between April 2012 and July 2014. Patient demographics, lesion characteristics, concurrent palliative therapies, and complications were recorded. Pre- and post-procedure mean worst pain scores 1 and 4weeks after treatment were measured using the Numeric Rating Scale (10-point scale) and compared. During the study period, 72 RFA treatments of 110 spinal metastases were performed. Eighty one percent (89/110) of metastases involved the posterior vertebral body and 45% (49/110) involved the pedicles. Vertebral augmentation was performed after 95% (105/110) of ablations. Mean and median pre-procedure pain scores were 8.0±1.9 and 8.0, respectively. Patients reported clinically significant decreased pain scores at both 1-week (mean, 3.9±3.0; median, 3.25; P<0.0001) and 4-week (mean, 2.9±3.0; median, 2.75; P<0.0001) follow-up. No major complications occurred related to RFA and there were no instances of symptomatic cement extravasation. CombinationRFA and vertebral augmentationis a safe and effective therapy for palliation of painful spinal metastases, including tumor involving the posterior vertebral body and/or pedicles.

Predictors of delayed failure of structural kyphoplasty for pathological compression fractures in cancer patients.

OBJECT Pathological compression fractures in cancer patients cause significant pain and disability. Spinal metastases affect quality of life near the end of life and may require multiple procedures, including medical palliative care and open surgical decompression and fixation. An increasingly popular minimally invasive technique to treat metastatic instabilities is kyphoplasty. Even though it may alleviate pain due to pathological fractures, it may fail. However, delayed kyphoplasty failures with retropulsed cement and neural element compression have not been well reported. Such failures necessitate open surgical decompression and stabilization, and cement inserted during the kyphoplasty complicates salvage surgeries in patients with a disease-burdened spine. The authors sought to examine the incidence of delayed failure of structural kyphoplasty in a series of cement augmentations for pathological compression fractures. The goal was to identify risk predictors by analyzing patient and disease characteristics to reduce kyphoplasty failure and to prevent excessive surgical procedures at the end of life. METHODS The authors retrospectively reviewed the records of all patients with metastatic cancer from 2010 to 2013 who had undergone a procedure involving cement augmentation for a pathological compression fracture at their institution. The authors examined the characteristics of the patients, diseases, and radiographic fractures. RESULTS In total, 37 patients underwent cement augmentation in 75 spinal levels during 45 surgeries. Four patients had delayed structural kyphoplasty failure necessitating surgical decompression and fusion. The mean time to kyphoplasty failure was 2.88 ± 1.24 months. The mean loss of vertebral body height was 16% in the patients in whom kyphoplasty failed and 32% in patients in whom kyphoplasty did not fail. No posterior intraoperative cement extravasation was observed in the patients in whom kyphoplasty had failed. The mean spinal instability neoplastic score was 10.8 in the patients in whom kyphoplasty failed and 10.1 in those in whom kyphoplasty did not fail. Approximately 50% of the kyphoplasty failures occurred at junctional spinal levels. All the patients in whom kyphoplasty failed had fractures in 3 or more cortical walls before treatment, whereas 46% of patients in the nonfailure group had fractures with breaching of 3 or more walls. CONCLUSIONS Although rare, delayed failures of structural augmentation with cement during kyphoplasty do occur and can lead to additional surgeries. A possible predictive index may include wall integrity of the vertebral body, competency of the posterior tension band, and location of the kyphoplasty at a junctional spinal level. Additional studies are required to confirm these findings.

A Novel Approach for Horizontal Sacral Insufficiency Fractures. Long Axis Kyphoplasty through Sacral Hiatus

Introduction Sacral insufficiency fractures (SIF) may cause significant low back pain, limit daily living, and tend to be undetected. Effective pain management and early mobilization are mandatory to prevent complications. Percutaneous sacroplasty for treatment of SIF has gained interest recently. This technique provides safe, rapid, and prolonged pain relief, early mobilization, and functional recovery. Sacral kyphoplasty is percutaneous placement of bone cement into the sacral vertebra using inflatable tamps. Both sacroplasty and sacral kyphoplasty are used for vertical component of the SIF. Highly trabecular pattern of sacral bone and proximity of sacral foramina and sacral canal limit the use of these techniques to sacral ala. We have described a new technique for injection of PMMA into proximal sacral vertebra. Patient and Methods: A 50-year-old patient with SIF at S1–S2 level was selected for this procedure. The patient was placed prone on the operation table. She was sedated using IV midazolam and fentanyl. The fluoroscopy was positioned so that sacral foramina could be clearly visualized on AP and lateral views. A stab incision was made following local anesthesia at the level of sacral hiatus. Bone access needle was introduced into the sacral hiatus above the superior margin of the coccyx under fluoroscopic guidance, similar to epiduroscopy. Epidural space was traversed and the corpus of distal sacral vertebra was reached. Entry point was checked in AP and lateral views. Needle tip was advanced proximal to the fracture line, into the S1. Once the ideal position of the needle was confirmed, guide pin and a working cannula were inserted. Balloon tamp was inserted and was inflated with 1.5 mL contrast dye to no more than 250 psi. Fluoroscopic control was performed to make sure that the inflated balloon did not breach cortices. Bone tamps were deflated and removed. The void was filled with radio opaque bone cement proximal to distal as cannula was slowly pulled back. Migration and extravasation of the cement was checked with fluoroscopy. Results The surgical procedure was completed in 25 minutes. Total fluoroscopy time was 10 minutes. There were no intraoperative or postoperative complications. While in the PACU, the patient declared that her pain had alleviated by half. She could mobilize freely in her room 2 hours after the intervention. No cement extravasation occurred. 24 hours following the surgery, she was completely pain free and was discharged from the hospital. On her last follow-up, she was completely asymptomatic, ambulatory, and could perform her daily activities by herself. Conclusion Sacroplasty and sacral kyphoplasty are generally used for Denis Zone 1 fractures. Proximity of the sacral foramina and sacral canal cause clinicians to avoid cement injection into sacral vertebral bodies. This procedure is very rarely performed. Use of pedicles to reach vertebral corpus restricts surgeon's ability to position cannula and pedicle fracture is another risk. With our long axis technique, bone cement can be injected into the sacral body in a longitudinal fashion with multiple sacral levels being augmented in a single entry.

Percutaneous Vertebroplasty: A New Technique Minimizing Cement Leak

Introduction Since the introduction of vertebroplasty to clinical practice, the cement leak is considered the most frequent and hazardous complication. In literature, the cement extravasation ranged from 26 to 97% of the time. This study discussed a new technique for injecting cement in the affected vertebra. Patients and Methods A total of 123 patients were treated by vertebroplasty using the current technique. The package of the cement powder and the solvent was divided into five equal parts. Each part of the powder and the solvent was mixed as a single dose and injected to the affected vertebra. The duration between subsequent injections was 10 minutes. Each injection is formed of 1 to 1.5 mL of cement. Results This new technique gives the surgeon enough time to make multiple separate injections with the same package. The time interval between injections makes cement harden enough and makes it not pushed by the next cement injection. This technique of injection gives time to the injected cement to seal off the cracks and cavities in the vertebra and subsequently leads to a highly significant decreased in cement leak ( p &lt; 0.001) compared with the literature. Conclusion This study demonstrates a previously unreported technique for vertebroplasty that adds more safety to the procedure by significantly decreasing cement leak. It also gives the surgeon much more relaxation time and self-confidence during performing the procedure.

Cement extravasation into the C7–T1 neural foramen after C7 vertebroplasty

Cement extravasation into the C7–T1 neural foramen after C7 vertebroplasty

Acute Spinal Subdural Hematoma after Vertebroplasty: A Case Report Emphasizing the Possible Etiologic Role of Venous Congestion

Study Design Case report and literature review. Objective Spinal subdural hematomas are rare events that often progress with severe neurologic deficits. Although there have been several case reports in the literature of spontaneous spinal subdural hematomas in the setting of anticoagulation, antiplatelet therapy, or coagulation disorders, the exact pathophysiology of such phenomena remains obscure. Methods We present the first report of a subdural hematoma after a percutaneous vertebroplasty and provide a comprehensive review on the anatomy of venous drainage of the vertebral bodies with emphasis on the possible effects of venous congestion caused by cement obstruction. Results Because the subdural hematoma occurred in the absence of major cement extravasation to the spinal canal and two levels above the site of the vertebroplasty, we discuss the possible role of venous congestion as the main etiologic factor leading to rupture of the fragile, valveless radiculomedullary veins into the subdural space. Conclusions The reported case supports a possible new pathophysiological scheme for the development of spinal subdural hematoma in which venous congestion plays a pivotal etiologic role. The reported findings suggests that future anatomical and histologic studies investigating the response of the radiculomedullary veins to congestive venous hypertension may shed new light into the pathophysiology of spinal subdural hematomas.

Use and evaluation of a semi-permeable mesh implant in vertebral augmentation for the treatment of painful osteoporotic vertebral compression fractures

ObjectiveTo assess the efficacy of a semi-permeable mesh implant in the treatment of painful thoracic and lumbar osteoporotic vertebral compression fractures.MethodsPatients with painful thoracic and lumbar osteoporotic vertebral compression fractures...

Minimally Invasive Technique for PMMA Augmentation of Fenestrated Screws.

Purpose. To describe the minimally invasive technique for cement augmentation of cannulated and fenestrated screws using an injection cannula as well as to report its safety and efficacy. Methods. A total of 157 cannulated and fenestrated pedicle screws had been cement-augmented during minimally invasive posterior screw-rod spondylodesis in 35 patients from January to December 2012. Retrospective evaluation of cement extravasation and screw loosening was carried out in postoperative plain radiographs and thin-sliced triplanar computed tomography scans. Results. Twenty-seven, largely prevertebral cement extravasations were detected in 157 screws (17.2%). None of the cement extravasations was causing a clinical sequela like a new neurological deficit. One screw loosening was noted (0.6%) after a mean follow-up of 12.8 months. We observed no cementation-associated complication like pulmonary embolism or hemodynamic insufficiency. Conclusions. The presented minimally invasive cement augmentation technique using an injection cannula facilitates convenient and safe cement delivery through polyaxial cannulated and fenestrated screws during minimally invasive screw-rod spondylodesis. Nevertheless, the optimal injection technique and design of fenestrated screws have yet to be identified. This trial is registered with German Clinical Trials DRKS00006726.

Percutaneous Vertebroplasty: A New Serial Injection Technique to Minimize Cement Leak.

Study DesignThis is a prospective cohort study.PurposeThis study discusses a new technique for injecting cement in the affected vertebrae.Overview of LiteratureSince introduction of vertebroplasty to clinical practice, the cement leak is considered the most frequent and hazardous complication. In literature, the cement extravasation occurred in 26%-97% of the cases.MethodsA hundred and twenty-three patients underwent vertebroplasty using the serial injection technique. The package of the cement powder and the solvent was divided into five equal parts. Each part of the powder and the solvent was mixed as a single dose and injected to the affected vertebra. The duration between subsequent injections was 10 minutes. Each injection consisted of 1-1.5 mL of cement.ResultsThis new technique gives the surgeon enough time to make multiple separate injections using the same package. The time interval between injections hardens the cement just enough so that it does not get displaced by the next cement injection. This technique gives time to the preceding injected cement to seal off the cracks and cavities in the vertebra, and subsequently leads to a significant decrease in cement leak (p<0.001), as compared to literature.ConclusionsThis study demonstrates a previously unreported technique for vertebroplasty that adds more safety to the procedure by significantly decreasing cement leak. It also makes the surgeon more relaxed due to time intervals, giving him more self-confidence whilst performing the procedure.

A randomized trial comparing balloon kyphoplasty and vertebroplasty for vertebral compression fractures due to osteoporosis.

Several trials have compared vertebral augmentation with nonsurgical treatment for vertebral compression fractures. This trial compares the efficacy and safety of balloon kyphoplasty and vertebroplasty. Patients with osteoporosis with 1-3 acute fractures (T5-L5) were randomized and treated with kyphoplasty (n = 191) or vertebroplasty (n = 190) and were not blinded to the treatment assignment. Twelve- and 24-month subsequent radiographic fracture incidence was the primary end point. Due to low enrollment and early withdrawals, the study was terminated with 404/1234 (32.7%) patients enrolled. The average age of patients was 75.6 years (77.4% female). Mean procedure duration was longer for kyphoplasty (40.0 versus 31.8 minutes, P < .001). At 12 months, 7.8% fewer patients with kyphoplasty (50/140 versus 57/131) had subsequent radiographic fracture, and there were 8.6% fewer at 24 months (54/110 versus 64/111). The results were not statistically significant (P > .21). When we used time to event for new clinical fractures, kyphoplasty approached statistical significance in longer fracture-free survival (Wilcoxon, P = .0596). Similar pain and function improvements were observed. CT demonstrated lower cement extravasation for kyphoplasty (157/214 versus 164/201 levels treated, P = .047). For kyphoplasty versus vertebroplasty, common adverse events within 30 postoperative days were procedural pain (12/191, 9/190), back pain (14/191, 28/190), and new vertebral fractures (9/191, 17/190); similar 2-year occurrence of device-related cement embolism (1/191, 1/190), procedural pain (3/191, 3/190), back pain (2/191, 3/190), and new vertebral fracture (2/191, 2/190) was observed. Kyphoplasty and vertebroplasty had similar long-term improvement in pain and disability with similar safety profiles and few device-related complications. Procedure duration was shorter with vertebroplasty. Kyphoplasty had fewer cement leakages and a trend toward longer fracture-free survival.

Results of kyphoplasty in the minimally invasive treatment of vertebral metastasis

OBJECTIVE: To evaluate the clinical and radiological outcome of minimally invasive surgical treatment of vertebral metastases using the technique of kyphoplasty. METHODS: This was a prospective observational study of patients with the diagnosis of spinal metastasis who underwent minimally invasive surgical treatment by filling the vertebral body with balloon kyphoplasty technique. Clinical evaluation included patient age at surgery, diagnosis of the tumor, biopsy results, data of the surgical procedure performed, visual pain scale (VAS) and complications related to surgery. Radiological evaluation involved the study of radiographic procedures in the anteroposterior and lateral incidences, with the analysis of vertebral body kyphosis and the occurrence of extravasation of cement. RESULTS: 22 patients with spinal metastases who were treated by balloon kyphoplasty, 8 (36%) males and 14 (64%) females were studied. The average age was 56.05 years and the mean follow-up was 8.5 months. The mean preoperative VAS was 8.73, 1.73 in the initial postoperative period, and 1.92 in the late postoperative period. CONCLUSION: Kyphoplasty proved to be a safe and effective technique for symptomatic treatment of vertebral metastases.

Functional Outcomes and Height Restoration for Patients With Multiple Myeloma-related Osteolytic Vertebral Compression Fractures Treated With Kyphoplasty

A retrospective review of pathologic vertebral fractures related to multiple myeloma. To report the functional status and height restoration of 32 patients treated with kyphoplasty for multiple myeloma-related vertebral compression fractures. Multiple myeloma can cause significant bony resorption, and vertebral involvement is extremely common. Compression fractures due to myelomatous vertebral metastases result in significant pain and can lead to kyphosis and sagittal imbalance. Nonoperative treatment can result in deformity and continued pain, and large surgical procedures have significant morbidity. Percutaneous cement augmentation (kyphoplasty and vertebroplasty) is a minimally invasive technique that can improve pain in these patients. Kyphoplasty also has the potential to provide mild deformity correction in addition to fracture stabilization. Study participants were patients with biopsy-proven multiple myeloma presenting with compression fracture treated with kyphoplasty. Data were compiled from patient charts and preoperative and postoperative radiographs. Patient self-reported functional status were obtained through the use of the Oswestry Disability Index. The degree of vertebral body collapse and deformity was evaluated using the method of Genant and analyzed using paired Student t test. Thirty-two consecutive patients who underwent kyphoplasty at a total of 76 levels for myelomatous vertebral compression fractures were identified. Sixteen fractures were at the thoracolumbar junction. The mean age was 64.3 years. The average Genant grade for the involved levels improved from 1.9 preoperative to 1.53 postoperative, which was statistically significant (P<0.0001). The postoperative Oswestry Disability Index score was obtained at a mean of 24 months, with a mean of 29.6%. Complications occurred in 12 (37.5%) patients, all consisting of minimal intraoperative cement extravasation without clinical sequelae. No changes in the neurological status were observed. The average hospital stay was 1.34 days postprocedure. Kyphoplasty for vertebral compression fractures due to multiple myeloma is a safe and effective procedure that can lead to pain relief and vertebral height restoration.

Enhancing Pedicle Screw Fixation in the Lumbar Spine Using Allograft Bone Plug Interference Fixation

A within-subjects controlled laboratory study. To examine a biological alternative to cement augmentation for pedicle screw fixation comparing bilateral axial pullout tests of augmented and nonaugmented (controls) pedicle screws. Fixation in the osteoporotic spine remains a difficult challenge with failure by loosening or backout. Pedicle screw augmentation has been attempted using polymethylmethacrylate and bioabsorbable calcium cements; however, the potential for extravasation and embolization of cement are becoming increasingly concerning and merit the search for alternative methods to improve screw-anchoring strength. Twenty-four (24) fresh human lumbar vertebrae were tested to compare the pullout strength of augmented and nonaugmented pedicle screws. Two different augmentation strategies were employed using allograft bone plugs (ABPs) and evaluated using 12 specimens per group. Bone mineral density of each specimen was obtained using dual-energy x-ray absorptiometry. The augmented versus nonaugmented pedicle was randomized for each vertebra, and bilateral testing enabled paired statistical analyses. Axial pullout tests were performed using an materials testing system servohydraulic test system, and peak force, failure displacement, and stiffness was obtained for each test and correlated with bone mineral density. Augmentation using 6-mm-diameter ABPs with 6.25-mm-diameter pedicle screws resulted in statistically weaker average pullout strength (775±455 N) than the nonaugmented controls (1233±826 N). When using smaller (5 mm diameter) AGPs with the same diameter screws, there was no statistical difference between average pullout strength for the augmented pedicle screws (1772±652 N) and the nonaugmented screws (1780±575 N). Preliminary study of pedicle screw augmentation using cannulated ABPs showed no improvement of fixation with pedicles in the spine. This was even true in osteoporotic specimens, where augmentation would seem to be of considerable benefit.

SAFETY AND EFFICACY OF BALLOON KYPHOPLASTY FOR COMPRESSION FRACTURES IN THE VERY ELDERLY

Introduction Balloon kyphoplasty is a well-accepted treatment for symptomatic compression fractures. Concern has been raised regarding unacceptable morbidity and poor outcomes in very elderly patients who undergo the procedure. This study was undertaken to evaluate the safety and efficacy of a series of very elderly patients who underwent balloon kyphoplasty. Materials Methods A retrospective cohort evaluation was performed of a consecutive series of 162 patients over age 80 who underwent treatment for compression fractures between 2006 and 2013 using the balloon kyphoplasty technique. The indication for treatment included pain unresponsive to non-surgical management in all cases. Results All procedures were successfully completed under general anesthesia. There were 43 men and 119 women (mean age 88, range 80-99 years). One hundred forty-two fractures were osteoporotic (23 had history of trauma), and 20 were pathologic. Fifty patients were treated in an outpatient setting. A total of 253 levels were treated, most common being L1 (n=38) and T12, L2 (n=35 each). Ninety- one patients had a single level treated, 56 had 2 levels treated, and 15 had 3 levels treated. The range of levels treated spanned from T4 (n=2) through L5 (n=11). Back pain improvement was used as the primary outcome measure. The mean VAS score for back pain improved from 9 to 3.5 (p&lt;0.0001). There were no cases of surgical site infections, cement extravasation, or new neurologic deficit for the entire cohort. Twenty-nine patients expired due to causes unrelated to the procedure during the follow-up period. Twenty- two (14%) patients underwent a second procedure for a new compression fracture after the index treatment at a mean interval of 7 weeks; 15 of these (68%) were performed at a level adjacent to the index level. Conclusion Balloon kyphoplasty is a safe and highly effective treatment for symptomatic compression fractures, even for very elderly patients. The procedure can be performed in an outpatient setting. Age alone should not be an exclusion criterion for candidate patients. Keywords: Balloon kyphoplasty, fracture, osteoporosis, surgery in the elderly, compression fractures

Percutaneous balloon kyphoplasty for the treatment of vertebral compression fractures

BackgroundVertebral compression fractures (VCFs) constitute a major health care problem, not only because of their high incidence but also because of their direct and indirect negative impacts on both patients’ health-related quality of life and costs to the health care system. Two minimally invasive surgical approaches were developed for the management of symptomatic VCFs: balloon kyphoplasty and vertebroplasty. The purpose of this study was to evaluate the effectiveness and safety of balloon kyphoplasty in the treatment of symptomatic VCFs.MethodsBetween July 2011 and June 2012, one hundred and eighty-seven patients with two hundred and fifty-one vertebras received balloon kyphoplasty in our hospital. There were sixty-five male and one hundred and twenty-two female patients with an average age of 74.5 (range, 61 to 95 years). The pain symptoms and quality of life, were measured before operation and at one day, three months, six months and one year following kyphoplasty. Radiographic data including restoration of kyphotic angle, anterior vertebral height, and any leakage of cement were defined.ResultsThe mean visual analog pain scale decreased from a preoperative value of 7.7 to 2.2 at one day (p < .05) following operation and the Oswestry Disability Index improved from 56.8 to 18.3 (p < .05). The kyphotic angle improved from a mean of 14.4° before surgery to 6.7° at one day after surgery (p < .05). The mean anterior vertebral height increased significantly from 52% before surgery to 74.5% at one day after surgery (p < .05) and 70.2% at one year follow-up. Minor cement extravasations were observed in twenty-nine out of two hundred and fifty-one procedures, including six leakage via basivertebral vein, three leakage via segmental vein and twenty leakage through a cortical defect. None of the leakages were associated with any clinical consequences.ConclusionsBalloon kyphoplasty not only rapidly reduced pain and disability but also restored sagittal alignment in our patients at one-year follow-up. The treatment of osteoporotic vertebral compression fractures with balloon kyphoplasty is a safe, effective, and minimally invasive procedure that provides satisfactory clinical results.