iprs000058 10.3205/iprs000058 urn:nbn:de:0183-iprs0000586 Research Article Die Bauchlagerung während der Ballon-Kyphoplastie führt nicht zu sekundären Kompressionsfrakturen in osteoporotischen Wirbelsäulen – eine MRT-Studie Spalteholz Spalteholz Matthias M Dr. med.

Klinik für Unfallchirurgie, Orthopädie und spezialisierte septische Chirurgie, Klinikum St. Georg Leipzig, GermanyKlinik für Unfallchirurgie, Orthopädie und spezialisierte septische Chirurgie, Klinikum St. Georg Leipzig, Germany

Matthias.Spalteholz@sanktgeorg.de author Strasser Strasser Evald E

Klinik für Unfallchirurgie, Orthopädie und spezialisierte septische Chirurgie, Klinikum St. Georg Leipzig, Germany

author Hantel Hantel Torsten T

Klinik für Diagnostische und Interventionelle Radiologie, FB Neuroradiologie, Klinikum St. Georg Leipzig, Germany

author Gahr Gahr Ralf Herbert RH

Klinik für Unfallchirurgie, Orthopädie und spezialisierte septische Chirurgie, Klinikum St. Georg Leipzig, Germany

author German Medical Science GMS Publishing House

Düsseldorf

610 osteoporotic vertebral compression fractures adjacent level fractures subsequent vertebral compression fractures balloon kyphoplasty prone positioning Osteoporotische Wirbelkörperkompressionsfrakturen Anschlussfrakturen Folgefrakturen Ballonkyphoplastie Bauchlagerung 20141218 engl 2193-8091 3 GMS Interdisciplinary Plastic and Reconstructive Surgery DGPW GMS Interdiscip Plast Reconstr Surg DGPW 17 Einleitung: Wirbelkörperkompressionsfrakturen sind die häufigsten Frakturen in geriatrischen Patienten. Persistierende Schmerzen und sekundäre Deformitäten sind verantwortlich für eine zunehmende Beeinträchtigung mit reduzierter Lebensqualität, erhöhter Morbidität und Mortalität. Die positiven Effekte der Ballon-Kyphoplastie wurden in vielen Studien bestätigt. Das Risiko für Folgefrakturen ist noch nicht abschließend geklärt. Es werden zement- und deformitätenabhängige Risiken diskutiert. Es gibt wenig Erkenntnis über das Risiko von Knochenmarködemen und frischen Frakturen während des Ballon-Kyphoplastie-Verfahrens. Das Ziel dieser Studie ist es zu untersuchen, ob die Bauchlagerung während der Kyphoplastie einen unabhängigen Risikofaktor für frische Frakturen in osteoporotischen Wirbelsäulen darstellt. Methoden: Es handelt sich um eine MRT-Studie an 20 Patienten, bei denen eine frische, nicht-traumatische thorakolumbale Wirbelkörperkompressionsfraktur mittels Ballon-Kyphoplastie behandelt wurde. Unmittelbar nach dem Eingriff wurden MRT-Untersuchungen der thorakolumbalen Wirbelsäule durchgeführt, noch bevor die Patienten mobilisiert wurden. Durch einen spezialisierten Neuroradiologen wurden postoperative MRT-Veränderungen wie Knochenmarködem, Signalintensitätsänderungen in den Anschlusssegmenten und frische Frakturen ausgewertet. Ergebnis: Es wurden 20 MRT-Untersuchungen innerhalb von 48 Stunden nach Ballon-Kyphoplastie durchgeführt. 85% zeigten keine Änderungen des vorbestehenden Knochenmarködems nach der Kyphoplastie. In drei Fällen zeigte sich eine geringe Zunahme des vorbestehenden Knochenmarködems in den augmentierten Wirbeln. Es wurden kein neues Knochenmarködem und keine neuen Frakturen in den Anschluss- und Folgesegmenten nach der Ballon-Kyphoplastie nachgewiesen. Schlussfolgerung: Die Bauchlagerung stellt kein Risiko für Anschlussfrakturen in osteoporotischen Wirbelsäulen dar. Purpose: Vertebral compression fractures are the most common fractures in the elderly. Long lasting pain and deformity is responsible for consecutive impairment with markedly reduced life quality, increased morbidity and mortality. The beneficial effects of balloon kyphoplasty are verified in many studies. Subsequent fracture risk is not finally clarified, cement related risks and deformity related risks are discussed. There is less knowledge about the risk of bone marrow edema and new fractures during balloon kyphoplasty procedure. The goal of this study is to examine, if prone position during kyphoplasty is an independent risk factor for new fractures in the osteoporotic spine. Methods: Consecutive MRI study of 20 patients with fresh, non-traumatic thoracolumbar vertebral compression fractures and balloon kyphoplasty treatment. MRI Scans of the thoracolumbar spine were obtained after surgery, before patients have been mobilized. Specific MRI changes like new bone marrow edema, signal intensity changes in adjacent and remote segments and new fractures were assessed by specialized neuro-radiologist. Results: 20 MR images were examined within 48 hours after balloon kyphoplasty procedure. 85% did not show bone marrow edema extent changes after kyphoplasty. We found minor increase of bone marrow edema within the augmented vertebral body in 3 cases. We did not find any new bone marrow edema and no new fractures in adjacent and remote segments after balloon kyphoplasty treatment.Conclusion: Prone position leads to no new bone marrow edema and no new fractures in the osteoporotic spine. Accordingly, prone position has no risk for adjacent level fractures in osteoporotic spines. IntroductionOne of the most important alteration in geriatric patients relates to the bone architecture. Typical changes start in cancellous bone, this explains why vertebral bodies are predestined for fractures and the thoracolumbar spine is the most affected area of osteoporotic fractures. Vertebral compression fractures (VCF) are the most common fractures in the elderly. The exact incidence is unknown. The worldwide prevalence is about 1.4 million (M) . The economical importance is considerable. In the USA, VCF caused total costs of 1 M US$ in 2005 and will rise up to 1.6 M US$ in 2025 . Treatment of VCF does not depend on morphological criteria, because most VCF are stable lesions. Long lasting pain is the most important factor that finally leads to surgery. Beneficial effects of vertebral body augmentation are demonstrated in various studies and pain reduction is the main effect , . Advantageous therapeutic effects are confronted with cement related problems , , and unclarified subsequent fracture risk , , , . This study examines the importance of prone position during balloon kyphoplasty for the development of additional bone marrow edemas (BME) and thoracolumbar fractures. Earlier studies already reported the possibility of height restoration (reduction) and profile correction in prone position as a phenomenon in fresh VCF with dynamic mobility .This aspect was fundamental for our hypothesis that prone position and reduction stress could also lead to new fractures in osteoporotic conditions. Because anaesthetized patients lose the tonus of their autochthon trunk muscles, prone position and additional reduction stress by chest and pelvic pads might overstrain the load bearing capacity of the spine, which may lead to microfractures or bone bruises. Prone positioning seems to have an additional risk in the osteoporotic spine. Patients and methodsEthic votumThis study received an approval from competent ethic committee.Patients 20 patients (6 men, 14 women) with fresh, non traumatic VCFs were included in this study. The average age was 78.4 years (64–94). Only patients older than 60 years were included in this study because of rising incidence of osteoporosis and spontaneous fractures in the elderly and we do not perform PMMA cement augmentation in patients under 60 years. The following inclusion criteria were determined:age >60 years no trauma pain less than 8 weeks MRI not older than two weekstype A1.1, A1.2 and A1.3 fractures according to Magerl’s classification only single fresh fracture in MRI.Exclusion criteria:previous spine surgeryno consent.Study period: February 2014 – May 2014.Fracture classification: Fractures were classified according to Magerl’s classification . MethodsStandard balloon kyphoplastyPatients were placed in prone position on a radiolucent op table with pads under the chest and pelvis and unstressed abdomen. Arms, knees and feet were padded to prevent nerve stretch and compression. Vertebral body height and alignment were tried to restore by varying pad position – increase/decrease of kyphosis or lordosis. Bilateral balloon kyphoplasty (Joimax SPASY) was performed in a standard manner, using 15 mm balloon in T5–T11 and 20 mm balloon in T12–L3 level. Balloons were inflated under fluoroscopy control up to a maximal volume of 2 ml (T5–T11), respectively 3 ml (T12–L3). The resulting cavity was filled with corresponding amounts of cement (each pedicle: 2 ml: T5–T11 and 3 ml: T12–L3). Consolidation time for PMMA cement (KyphX HV-R, Kyphon®) was 10 minutes. MR imaging MRI examination included sagittal and axial planes of the thoracolumbar spine using 3.0 tesla MRI system (Siemens TIM TRIO). Following sequences were performed: Preoperative protocol:T1-weighted TSE sagittal (TR 526 ms, TE 10 ms, FOV 450 mm, SL 4 mm)T2-weighted TSE sagittal (TR 3900 ms, TE 94 ms, FOV 450 mm, SL 4 mm)T2-weighted TIRM sagittal (TR 5000 ms, TE 54 ms, FOV 450 mm, fatsupression, SL 4 mm)T2-weighted TSE transversal (TR 4250 ms, TE 118 ms, FOV 270 mm, SL 3 mm)Postprocedural protocol: Same protocol without T2-weighted TSE sagittalFresh fractures and bone marrow edema (bone bruise) were detected by decreased signal intensity on T1-weighted images, high signal intensity on T2-weighted and T2-weighted images with fat suppression (TIRM) . Each MRI was analyzed by the same specialized neuro-radiologist. The extent of bone marrow edema (BME) was assessed in sagittal TIRM images as percentage of volume of the fractured vertebral body. Three groups were classified: minor <25%, moderate 25–75% and severe >75%. Postoperative MRI control was performed within 48 h after surgery. Patients had absolute bed rest until postoperative MRI. BME extent between pre- and postoperative images was classified into less, the same, or more. ResultsTypes of fracturesFigure 1 shows the different types of fractures.Fracture distributionMost fractures were localized at T12 level (30%), followed by L1 (25%) and T10 (15%). 55% of the fractures were localized at the thoracolumbar junction (T12–L1). Figure 2 shows the different fracture levels. MRI findingsBone marrow edemaPreprocedural MRI evaluation revealed minor BME extent in one case. The majority revealed moderate and severe edemas (45% moderate, 50% severe). 85% did not show BME extent changes after kyphoplasty. Change of BME extent in postprocedural MRI was detected in 3 patients: one patient with preoperative minor edema showed moderate edema and 2 patients with moderate edemas showed severe edemas in postprocedural MRI. We did not find less extent of BME after kyphoplasty (Figure 3 ).Bright rim signBright rim surrounding the cement on STIR weighted images (hypointense signal on T1-weighted images) represents a necrotic area as result of heat related local vertebral ischemia , , . We did not recognize bright rim sign in any post-procedural MRI. Adjacent segment/remote segmentsIncreased signal intensity in both adjacent discs (sagittal TIRM sequence) was seen in one case. In this case, we also found change of BME extent from moderate to severe. In one case we recognized cement extrusion into the cephaled disc space which led to hyperintense signal in TIRM sequence. There was no signal alteration in remote segments, neither in disc spaces, nor in any vertebral bodies. There was no new bone marrow edema and no new fracture, neither in adjacent nor in remote segments (Figure 4 ).Intraoperative ComplicationsWe identified two cement extrusions: one into the upper disc space and one anteriorly, protruding into the retroperitoneal space. DiscussionReduced bone mineral density is responsible for less mechanical stability with subsequent height loss and finally VCF in osteoporotic conditions. Interestingly, only 30% of all fractures become symptomatically . Patients with long lasting pain, missing recovery and pain related immobilization, may benefit of minimally invasive vertebral cement augmentation , , . Balloon kyphoplasty is one of the most common augmentation techniques and well investigated. Pain reduction is a crucial effect, which is well confirmed, even 2 years after kyphoplasty . Additional to pain reducing effect, operative therapy is important for preservation of balanced spine profile. Especially in thoracic spine, vertebral compression fractures may lead to progressive kyphosis, deformity and restriction of pulmonary function . In spite of its beneficial effects, risks of minimally invasive surgery related complications should not be underestimated: cement leakage up to 33% , pulmonary embolism up to 23% , neurologic deficits in 3.7%, spinal cord compression in 0.5% , . Further, a not finally solved phenomenon is the presence of adjacent level and subsequent fractures after vertebral body augmentation. Reviewing the literature, three main hypotheses are discussed:New fractures after cement augmentation may develop due to progress of disease – untreated osteoporosis . New fractures after cement augmentation may develop due to too large cement volumes and increased stiffness .New fractures after cement augmentation may result due to kyphotic deformity , .The risk of subsequent fractures rises with the number of pre-existing deformities, independently of the bone quality. Three and more present fractures have a 35-fold increased subsequent fracture risk , . Adjacent level fracture risk is also increased by increased vertebral body stiffness in case of too large cement volumes . Finite element analysis demonstrated optimal volumes of 3.5 cm³, to restore the original stiffness in vertebral bodies. Larger amounts increase the stiffness above original values . Due to excessive augmentation, the cement acts like a pillar with reduction of the physiologically endplate concavity or even convex deformity. The intradiscal pressure is increased up to 19% , resulting in adjacent level fractures , . Other authors assert that progressive kyphotic deformity is responsible for subsequent fractures. Wedge formation may lead to an anterior load shift with increased bending moments and additionally compression of the anterior column , . These explanations demonstrate that the risk of subsequent and adjacent level fractures after cement augmentation is not finally clarified. Studies reported an incidence of subsequent fractures after balloon kyphoplasty between 7 and 26% , , , , . Regarding onset of recurrent fractures, most authors report a peak within 12 months , , . Trout et al. reported an early onset within 30 days, with high risk in case of cement extrusion into the disc space . Fribourg et al. reported an increased incidence of subsequent vertebral fractures after kyphoplasty within 60 days after balloon kyphoplasty . Finally, exact date is not clarified. It is not excluded, that early bony changes take already place during kyphoplasty procedure.Reviewing the literature, the authors did not find any study that examines the role of prone position as an independent risk factor for new fractures in osteoporotic spine. With respect to the biomechanical findings described above, peri-procedural conditions during kyphoplasty may be decisive. General anaesthesia with full muscle relaxation prevents muscular trunk stabilization in prone position. Pads under chest and pelvis increase mechanical loads by eccentric forces. This might be enough to overstrain the weak bone consistency in osteoporotic spine and lead to microfractures. These microfractures are the beginning of continuing height loss and should be detected immediately after kyphoplasty. Magnetic resonance tomography is the method of choice. MR imaging is the gold standard to prove fresh lesions with a reported sensitivity of 99% and specificity of 98.7% for fresh vertebral fractures . It is the modality of choice to assess traumatic lesions . MRI is able to detect fresh lesions, before vertebral body height loss is visible in X-ray and computed tomography. Acute vertebral fractures and BME are most sensitive detected in sagittal STIR images , , , , , . Bone marrow pathologies are best evaluated in T1-weighted sequences on 3 Tesla MRI . However, the crucial question is, when can first signal changes be detected in MRI. The authors did find no study that examined the time, when BME arises first. On the other hand, it is well known, how long these signal alterations are detectable. BME decreases gradual over time with complete vanishing after three months in 35%, at 6 months in 54% and 12 months in 71% , . To the authors opinion, the best way to detect fresh lesions immediately after kyphoplasty procedure, is by 3 Tesla MRI. In our study, evaluation of 20 post procedural 3 Tesla MRI by one spezialized neuro radiologist did show no new bone marrow edema and no new fracture in adjacent and remote segments. 85% did not show BME extent changes within the augmented vertebral body in post procedural MRI. We did not find less extent of BME after kyphoplasty. We did not recognize bright rim sign in any post-procedural MRI. In one case we found increased signal intensity in sagittal TIRM sequence in both adjacent discs. In this case, we also found change of BME extent from moderate to severe. In one case we recognized cement extrusion into the cephaled disc space and increased signal intensity in TIRM sequence. The goal of this study was to evaluate the risk of prone position during balloon kyphoplasty and new vertebral compression fractures in generally anesthetized patients in osteoporotic spine. Benefit of this study was standardized operative protocol with determined volumes of balloon inflation and cement amounts in thoracic and lumbar levels to reduce the well-known cement related subsequent fracture risk. Further, we used identical MRI protocols and received each MRI within 48 hours after kyphoplasty. Because patients had bed rest till they received MRI, we minimized additional risks of signal alterations. Interobserver variability was reduced by MRI evaluation by only one specialized neuro-radiologist. On the other hand, this study has some limitations. We did not measure bone mineral density (BMD) to proof osteoporosis. We defined osteoporotic vertebral compression fracture by average age older than 60 years, no recent trauma and typical findings in MRI, which was not older than two weeks. Postoperative MRI was not blinded to preoperative MRI. It was the aim to detect extent changes of BME, new bone marrow edema and new fractures. So we think it is important to compare these findings to the pre-procedural MRI. Further, we often recognized preexisting degenerative findings. It was important for us to look if these findings changed or increased post-procedural. We performed post-procedural MRI within 48 hours. As mentioned above, the authors did not find studies that examined the beginning of MRI signal changes. It might be that these changes occur later and we could not have detected them. But if we had performed post-procedural MRI later, the risk of further factors influencing MRI signal intensity would also rise. The main limitation is the small number of patients (20 patients). This reveals only fractures if the prevalence is higher than 5%. If prevalence was close to 1%, 100 patients would be needed. On the other hand, there is a reported incidence of subsequent fractures after balloon kyphoplasty between 7 and 26% with a peak within 12 months. This means that these fractures could occur also within the first days after kyphoplasty. And than prone position could play a major role for secondary vertebral compression fractures in osteoporotic spine. ConclusionsKyphoplasty is well established in the treatment of osteoporotic VCF. The risk of adjacent level and subsequent fractures is not fully clarified. Various causes are discussed. The influence of prone position and external reduction stress is not investigated yet. This is the first consecutive MRI study, which examines the role of prone position in kyphoplasty treatment of osteoporotic vertebral compression fractures. The aim of this study was to examine, if prone position in anaesthetized patients is an independent risk factor for new fractures in osteoporotic conditions. MRI evaluation of 20 thoracolumbar VCF, immediately after balloon kyphoplasty treatment, did not show bone marrow edema (bone bruise) and new vertebral compression fracture in adjacent and remote segments. Accordingly, prone position has no risk for adjacent level fractures in osteoporotic spines. NotesCompeting interestsThe authors declare that they have no competing interests. Johnell O Kanis JA An estimate of the worldwide prevalence and disability associated with osteoporotic fractures 2006 Osteoporos Int 1726-33 Johnell O, Kanis JA. An estimate of the worldwide prevalence and disability associated with osteoporotic fractures. Osteoporos Int. 2006 Dec;17(12):1726-33. DOI: 10.1007/s00198-006-0172-4 http://dx.doi.org/10.1007/s00198-006-0172-4 Burge R Dawson-Hughes B Solomon DH Wong JB King A Tosteson A Incidence and economic burden of osteoporosis-related fractures in the United States, 2005-2025 2007 J Bone Miner Res 465-75 Burge R, Dawson-Hughes B, Solomon DH, Wong JB, King A, Tosteson A. Incidence and economic burden of osteoporosis-related fractures in the United States, 2005-2025. J Bone Miner Res. 2007 Mar;22(3):465-75. DOI: 10.1359/jbmr.061113 http://dx.doi.org/10.1359/jbmr.061113 Wardlaw D Cummings SR Van Meirhaeghe J Bastian L Tillman JB Ranstam J Eastell R Shabe P Talmadge K Boonen S Efficacy and safety of balloon kyphoplasty compared with non-surgical care for vertebral compression fracture (FREE): a randomised controlled trial 2009 Lancet 1016-24 Wardlaw D, Cummings SR, Van Meirhaeghe J, Bastian L, Tillman JB, Ranstam J, Eastell R, Shabe P, Talmadge K, Boonen S. Efficacy and safety of balloon kyphoplasty compared with non-surgical care for vertebral compression fracture (FREE): a randomised controlled trial. Lancet. 2009 Mar;373(9668):1016-24. DOI: 10.1016/S0140-6736(09)60010-6 http://dx.doi.org/10.1016/S0140-6736(09)60010-6 Boonen S Van Meirhaeghe J Bastian L Cummings SR Ranstam J Tillman JB Eastell R Talmadge K Wardlaw D Balloon kyphoplasty for the treatment of acute vertebral compression fractures: 2-year results from a randomized trial 2011 J Bone Miner Res 1627-37 Boonen S, Van Meirhaeghe J, Bastian L, Cummings SR, Ranstam J, Tillman JB, Eastell R, Talmadge K, Wardlaw D. Balloon kyphoplasty for the treatment of acute vertebral compression fractures: 2-year results from a randomized trial. J Bone Miner Res. 2011 Jul;26(7):1627-37. DOI: 10.1002/jbmr.364 http://dx.doi.org/10.1002/jbmr.364 Polikeit A Nolte LP Ferguson SJ The effect of cement augmentation on the load transfer in an osteoporotic functional spinal unit: finite-element analysis 2003 Spine 991-6 Polikeit A, Nolte LP, Ferguson SJ. The effect of cement augmentation on the load transfer in an osteoporotic functional spinal unit: finite-element analysis. Spine. 2003 May;28(10):991-6. DOI: 10.1097/01.BRS.0000061987.71624.17 http://dx.doi.org/10.1097/01.BRS.0000061987.71624.17 Liebschner MA Rosenberg WS Keaveny TM Effects of bone cement volume and distribution on vertebral stiffness after vertebroplasty 2001 Spine 1547-54 Liebschner MA, Rosenberg WS, Keaveny TM. Effects of bone cement volume and distribution on vertebral stiffness after vertebroplasty. Spine. 2001 Jul;26(14):1547-54. DOI: 10.1097/00007632-200107150-00009 http://dx.doi.org/10.1097/00007632-200107150-00009 Baroud G Nemes J Heini P Steffen T Load shift of the intervertebral disc after a vertebroplasty: a finite-element study 2003 Eur Spine J 421-6 Baroud G, Nemes J, Heini P, Steffen T. Load shift of the intervertebral disc after a vertebroplasty: a finite-element study. Eur Spine J. 2003 Aug;12(4):421-6. DOI: 10.1007/s00586-002-0512-9 http://dx.doi.org/10.1007/s00586-002-0512-9 Lunt M O'Neill TW Felsenberg D Reeve J Kanis JA Cooper C Silman AJ European Prospective Osteoporosis Study Group Characteristics of a prevalent vertebral deformity predict subsequent vertebral fracture: results from the European Prospective Osteoporosis Study (EPOS) 2003 Bone 505-13 Lunt M, O'Neill TW, Felsenberg D, Reeve J, Kanis JA, Cooper C, Silman AJ; European Prospective Osteoporosis Study Group. Characteristics of a prevalent vertebral deformity predict subsequent vertebral fracture: results from the European Prospective Osteoporosis Study (EPOS). Bone. 2003 Oct;33(4):505-13. DOI: 10.1016/S8756-3282(03)00248-5 http://dx.doi.org/10.1016/S8756-3282(03)00248-5 Klotzbuecher CM Ross PD Landsman PB Abbott TA 3rd Berger M Patients with prior fractures have an increased risk of future fractures: a summary of the literature and statistical synthesis 2000 J Bone Miner Res 721-39 Klotzbuecher CM, Ross PD, Landsman PB, Abbott TA 3rd, Berger M. Patients with prior fractures have an increased risk of future fractures: a summary of the literature and statistical synthesis. J Bone Miner Res. 2000 Apr;15(4):721-39. DOI: 10.1359/jbmr.2000.15.4.721 http://dx.doi.org/10.1359/jbmr.2000.15.4.721 Lin EP Ekholm S Hiwatashi A Westesson PL Vertebroplasty: cement leakage into the disc increases the risk of new fracture of adjacent vertebral body 2004 AJNR Am J Neuroradiol 175-80 Lin EP, Ekholm S, Hiwatashi A, Westesson PL. Vertebroplasty: cement leakage into the disc increases the risk of new fracture of adjacent vertebral body. AJNR Am J Neuroradiol. 2004 Feb;25(2):175-80. Trout AT Kallmes DF Lane JI Layton KF Marx WF Subsequent vertebral fractures after vertebroplasty: association with intraosseous clefts 2006 AJNR Am J Neuroradiol 1586-91 Trout AT, Kallmes DF, Lane JI, Layton KF, Marx WF. Subsequent vertebral fractures after vertebroplasty: association with intraosseous clefts. AJNR Am J Neuroradiol. 2006 Aug;27(7):1586-91. Dublin AB Hartman J Latchaw RE Hald JK Reid MH The vertebral body fracture in osteoporosis: restoration of height using percutaneous vertebroplasty 2005 AJNR Am J Neuroradiol 489-92 Dublin AB, Hartman J, Latchaw RE, Hald JK, Reid MH. The vertebral body fracture in osteoporosis: restoration of height using percutaneous vertebroplasty. AJNR Am J Neuroradiol. 2005 Mar;26(3):489-92. Magerl F Aebi M Gertzbein SD Harms J Nazarian S A comprehensive classification of thoracic and lumbar injuries 1994 Eur Spine J 184-201 Magerl F, Aebi M, Gertzbein SD, Harms J, Nazarian S. A comprehensive classification of thoracic and lumbar injuries. Eur Spine J. 1994;3(4):184-201. DOI: 10.1007/BF02221591 http://dx.doi.org/10.1007/BF02221591 Do HM Magnetic resonance imaging in the evaluation of patients for percutaneous vertebroplasty 2000 Top Magn Reson Imaging 235-44 Do HM. Magnetic resonance imaging in the evaluation of patients for percutaneous vertebroplasty. Top Magn Reson Imaging. 2000 Aug;11(4):235-44. DOI: 10.1097/00002142-200008000-00004 http://dx.doi.org/10.1097/00002142-200008000-00004 Voormolen MH van Rooij WJ van der Graaf Y Lohle PN Lampmann LE Juttmann JR Sluzewski M Bone marrow edema in osteoporotic vertebral compression fractures after percutaneous vertebroplasty and relation with clinical outcome 2006 AJNR Am J Neuroradiol 983-8 Voormolen MH, van Rooij WJ, van der Graaf Y, Lohle PN, Lampmann LE, Juttmann JR, Sluzewski M. Bone marrow edema in osteoporotic vertebral compression fractures after percutaneous vertebroplasty and relation with clinical outcome. AJNR Am J Neuroradiol. 2006 May;27(5):983-8. Deramond H Wright NT Belkoff SM Temperature elevation caused by bone cement polymerization during vertebroplasty 1999 Bone 17S-21S Deramond H, Wright NT, Belkoff SM. Temperature elevation caused by bone cement polymerization during vertebroplasty. Bone. 1999 Aug;25(2 Suppl):17S-21S. DOI: 10.1016/S8756-3282(99)00127-1 http://dx.doi.org/10.1016/S8756-3282(99)00127-1 Verlaan JJ Oner FC Verbout AJ Dhert WJ Temperature elevation after vertebroplasty with polymethyl-methacrylate in the goat spine 2003 J Biomed Mater Res Part B Appl Biomater 581-5 Verlaan JJ, Oner FC, Verbout AJ, Dhert WJ. Temperature elevation after vertebroplasty with polymethyl-methacrylate in the goat spine. J Biomed Mater Res Part B Appl Biomater. 2003 Oct;67(1):581-5. DOI: 10.1002/jbm.b.20002 http://dx.doi.org/10.1002/jbm.b.20002 Lindsay R Pack S Li Z Longitudinal progression of fracture prevalence through a population of postmenopausal women with osteoporosis 2005 Osteoporos Int 306-12 Lindsay R, Pack S, Li Z. Longitudinal progression of fracture prevalence through a population of postmenopausal women with osteoporosis. Osteoporos Int. 2005 Mar;16(3):306-12. DOI: 10.1007/s00198-004-1691-5 http://dx.doi.org/10.1007/s00198-004-1691-5 Voormolen MH Mali WP Lohle PN Fransen H Lampmann LE van der Graaf Y Juttmann JR Jansssens X Verhaar HJ Percutaneous vertebroplasty compared with optimal pain medication treatment: short-term clinical outcome of patients with subacute or chronic painful osteoporotic vertebral compression fractures. The VERTOS study 2007 AJNR Am J Neuroradiol 555-60 Voormolen MH, Mali WP, Lohle PN, Fransen H, Lampmann LE, van der Graaf Y, Juttmann JR, Jansssens X, Verhaar HJ. Percutaneous vertebroplasty compared with optimal pain medication treatment: short-term clinical outcome of patients with subacute or chronic painful osteoporotic vertebral compression fractures. The VERTOS study. AJNR Am J Neuroradiol. 2007 Mar;28(3):555-60. Dong R Chen L Gu Y Han G Yang H Tang T Xiaoqing C Improvement in respiratory function after vertebroplasty and kyphoplasty 2009 Int Orthop 1689-94 Dong R, Chen L, Gu Y, Han G, Yang H, Tang T, Xiaoqing C. Improvement in respiratory function after vertebroplasty and kyphoplasty. Int Orthop. 2009 Dec;33(6):1689-94. DOI: 10.1007/s00264-008-0680-2 http://dx.doi.org/10.1007/s00264-008-0680-2 Hulme PA Krebs J Ferguson SJ Berlemann U Vertebroplasty and kyphoplasty: a systematic review of 69 clinical studies 2006 Spine 1983-2001 Hulme PA, Krebs J, Ferguson SJ, Berlemann U. Vertebroplasty and kyphoplasty: a systematic review of 69 clinical studies. Spine. 2006 Aug;31(17):1983-2001. DOI: 10.1097/01.brs.0000229254.89952.6b http://dx.doi.org/10.1097/01.brs.0000229254.89952.6b Choe DH Marom EM Ahrar K Truong MT Madewell JE Pulmonary embolism of polymethyl methacrylate during percutaneous vertebroplasty and kyphoplasty 2004 AJR Am J Roentgenol 1097-102 Choe DH, Marom EM, Ahrar K, Truong MT, Madewell JE. Pulmonary embolism of polymethyl methacrylate during percutaneous vertebroplasty and kyphoplasty. AJR Am J Roentgenol. 2004 Oct;183(4):1097-102. DOI: 10.2214/ajr.183.4.1831097 http://dx.doi.org/10.2214/ajr.183.4.1831097 Brown DB Gilula LA Sehgal M Shimony JS Treatment of chronic symptomatic vertebral compression fractures with percutaneous vertebroplasty 2004 AJR Am J Roentgenol 319-22 Brown DB, Gilula LA, Sehgal M, Shimony JS. Treatment of chronic symptomatic vertebral compression fractures with percutaneous vertebroplasty. AJR Am J Roentgenol. 2004 Feb;182(2):319-22. DOI: 10.2214/ajr.182.2.1820319 http://dx.doi.org/10.2214/ajr.182.2.1820319 Lindsay R Silverman SL Cooper C Hanley DA Barton I Broy SB Licata A Benhamou L Geusens P Flowers K Stracke H Seeman E Risk of new vertebral fracture in the year following a fracture 2001 JAMA 320-3 Lindsay R, Silverman SL, Cooper C, Hanley DA, Barton I, Broy SB, Licata A, Benhamou L, Geusens P, Flowers K, Stracke H, Seeman E. Risk of new vertebral fracture in the year following a fracture. JAMA. 2001 Jan;285(3):320-3. DOI: 10.1001/jama.285.3.320 http://dx.doi.org/10.1001/jama.285.3.320 Uppin AA Hirsch JA Centenera LV Pfiefer BA Pazianos AG Choi IS Occurrence of new vertebral body fracture after percutaneous vertebroplasty in patients with osteoporosis 2003 Radiology 119-24 Uppin AA, Hirsch JA, Centenera LV, Pfiefer BA, Pazianos AG, Choi IS. Occurrence of new vertebral body fracture after percutaneous vertebroplasty in patients with osteoporosis. Radiology. 2003 Jan;226(1):119-24. DOI: 10.1148/radiol.2261011911 http://dx.doi.org/10.1148/radiol.2261011911 Garfin S Lin G Liebermann I Phillips F Truumees E Retrospective analysis of the outcome of balloon kyphoplasty to treat vertebral body compression fracture (VCF) refractory to medical management 2001 Eur Spine J S7 Garfin S, Lin G, Liebermann I, Phillips F, Truumees E. Retrospective analysis of the outcome of balloon kyphoplasty to treat vertebral body compression fracture (VCF) refractory to medical management. Eur Spine J. 2001;10 (Suppl 1):S7. Fribourg D Tang C Sra P Delamarter R Bae H Incidence of subsequent vertebral fracture after kyphoplasty 2004 Spine 2270-6 Fribourg D, Tang C, Sra P, Delamarter R, Bae H. Incidence of subsequent vertebral fracture after kyphoplasty. Spine. 2004 Oct;29(20):2270-6. DOI: 10.1097/01.brs.0000142469.41565.2a http://dx.doi.org/10.1097/01.brs.0000142469.41565.2a Grafe IA Da Fonseca K Hillmeier J Meeder PJ Libicher M Nldge G Bardenheuer H Pyerin W Basler L Weiss C Taylor RS Nawroth P Kasperk C Reduction of pain and fracture incidence after kyphoplasty: 1-year outcomes of a prospective controlled trial of patients with primary osteoporosis 2005 Osteoporos Int 2005-12 Grafe IA, Da Fonseca K, Hillmeier J, Meeder PJ, Libicher M, Nldge G, Bardenheuer H, Pyerin W, Basler L, Weiss C, Taylor RS, Nawroth P, Kasperk C. Reduction of pain and fracture incidence after kyphoplasty: 1-year outcomes of a prospective controlled trial of patients with primary osteoporosis. Osteoporos Int. 2005 Dec;16(12):2005-12. DOI: 10.1007/s00198-005-1982-5 http://dx.doi.org/10.1007/s00198-005-1982-5 Donovan MA Khandji AG Siris E Multiple adjacent vertebral fractures after kyphoplasty in a patient with steroid-induced osteoporosis 2004 J Bone Miner Res 712-3 Donovan MA, Khandji AG, Siris E. Multiple adjacent vertebral fractures after kyphoplasty in a patient with steroid-induced osteoporosis. J Bone Miner Res. 2004 May;19(5):712-3. DOI: 10.1359/JBMR.040207 http://dx.doi.org/10.1359/JBMR.040207 Lavelle WF Cheney R Recurrent fracture after vertebral kyphoplasty 2006 Spine J 488-93 Lavelle WF, Cheney R. Recurrent fracture after vertebral kyphoplasty. Spine J. 2006 Sep-Oct;6(5):488-93. DOI: 10.1016/j.spinee.2005.10.013 http://dx.doi.org/10.1016/j.spinee.2005.10.013 Silverman SL Minshall ME Shen W Harper KD Xie S Health-Related Quality of Life Subgroup of the Multiple Outcomes of Raloxifene Evaluation Study The relationship of health-related quality of life to prevalent and incident vertebral fractures in postmenopausal women with osteoporosis: results from the Multiple Outcomes of Raloxifene Evaluation Study 2001 Arthritis Rheum 2611-9 Silverman SL, Minshall ME, Shen W, Harper KD, Xie S; Health-Related Quality of Life Subgroup of the Multiple Outcomes of Raloxifene Evaluation Study. The relationship of health-related quality of life to prevalent and incident vertebral fractures in postmenopausal women with osteoporosis: results from the Multiple Outcomes of Raloxifene Evaluation Study. Arthritis Rheum. 2001 Nov;44(11):2611-9. DOI: 10.1002/1529-0131(200111)44:11<2611::AID-ART441>3.0.CO;2-N http://dx.doi.org/10.1002/1529-0131(200111)44:11<2611::AID-ART441>3.0.CO;2-N Trout AT Kallmes DF Does vertebroplasty cause incident vertebral fractures? A review of available data 2006 AJNR Am J Neuroradiol 1397-403 Trout AT, Kallmes DF. Does vertebroplasty cause incident vertebral fractures? A review of available data. AJNR Am J Neuroradiol. 2006 Aug;27(7):1397-403. Nakano T Ochi R Miyazono K Diagnosis precision of MRI for fresh osteoporotic vertebral body fracture and a diagnosis by follow-up roentgenogram 2004 Osteoporos Jpn 89-90 Nakano T, Ochi R, Miyazono K, et al. Diagnosis precision of MRI for fresh osteoporotic vertebral body fracture and a diagnosis by follow-up roentgenogram. Osteoporos Jpn. 2004;12:89-90. Yamato M Nishimura G Kuramochi E Saiki N Fujioka M MR appearance at different ages of osteoporotic compression fractures of the vertebrae 1998 Radiat Med 329-34 Yamato M, Nishimura G, Kuramochi E, Saiki N, Fujioka M. MR appearance at different ages of osteoporotic compression fractures of the vertebrae. Radiat Med. 1998 Sep-Oct;16(5):329-34. Kanal E Barkovich AJ Bell C Borgstede JP Bradley WG Jr Froelich JW Gilk T Gimbel JR Gosbee J Kuhni-Kaminski E Lester JW Jr Nyenhuis J Parag Y Schaefer DJ Sebek-Scoumis EA Weinreb J Zaremba LA Wilcox P Lucey L Sass N ACR Blue Ribbon Panel on MR Safety ACR guidance document for safe MR practices: 2007 2007 AJR Am J Roentgenol 1447-74 Kanal E, Barkovich AJ, Bell C, Borgstede JP, Bradley WG Jr,Froelich JW, Gilk T, Gimbel JR, Gosbee J, Kuhni-Kaminski E, Lester JW Jr,Nyenhuis J, Parag Y, Schaefer DJ, Sebek-Scoumis EA, Weinreb J, Zaremba LA, Wilcox P, Lucey L, Sass N; ACR Blue Ribbon Panel on MR Safety. ACR guidance document for safe MR practices: 2007. AJR Am J Roentgenol. 2007 Jun;188(6):1447-74. DOI: 10.2214/AJR.06.1616 http://dx.doi.org/10.2214/AJR.06.1616 Button JH Petron DJ Pedicle stress reaction in a teenage baseball pitcher 2007 Am J Phys Med Rehabil 956 Button JH, Petron DJ. Pedicle stress reaction in a teenage baseball pitcher. Am J Phys Med Rehabil. 2007 Nov;86(11):956. Parizel PM Gielen JL Vanhoenacker FM The spine in sports injuries: the cervical spine 2007 Imaging of orthopedic sports injuries 377-90 Parizel PM, Gielen JL, Vanhoenacker FM. The spine in sports injuries: the cervical spine. In: Vanhoenacker FM, Maes M, Gielen JL, editors. Imaging of orthopedic sports injuries. Berlin: Springer; 2007. p. 377-90. DOI: 10.1007/978-3-540-68201-1_22 http://dx.doi.org/10.1007/978-3-540-68201-1_22 Baker LL Goodman SB Perkash I Lane B Enzmann DR Benign versus pathologic compression fractures of vertebral bodies: assessment with conventional spin-echo, chemical-shift, and STIR MR imaging 1990 Radiology 495-502 Baker LL, Goodman SB, Perkash I, Lane B, Enzmann DR. Benign versus pathologic compression fractures of vertebral bodies: assessment with conventional spin-echo, chemical-shift, and STIR MR imaging. Radiology. 1990 Feb;174(2):495-502. DOI: 10.1148/radiology.174.2.2296658 http://dx.doi.org/10.1148/radiology.174.2.2296658 Dansie DM Luetmer PH Lane JI Thielen KR Wald JT Kallmes DF MRI findings after successful vertebroplasty 2005 AJNR Am J Neuroradiol 1595-600 Dansie DM, Luetmer PH, Lane JI, Thielen KR, Wald JT, Kallmes DF. MRI findings after successful vertebroplasty. AJNR Am J Neuroradiol. 2005 Jun-Jul;26(6):1595-600. Available from: http://www.ajnr.org/content/26/6/1595.long http://www.ajnr.org/content/26/6/1595.long Allen GM Dark t1 bone marrow 2011 Semin Musculoskelet Radiol 247-56 Allen GM. Dark t1 bone marrow. Semin Musculoskelet Radiol. 2011 Jul;15(3):247-56. DOI: 10.1055/s-0031-1278424 http://dx.doi.org/10.1055/s-0031-1278424 0

1 1 Figure1: Types of fractures

2 2 Figure 2: Distribution of fractures

3 3 Figure 3: Bone marrow edema

4 4 Figure 4: Scans1 Pre-procedural sagittal T1-weighted Scan: hypointense signal in L1 2 Post-procedural sagittal T1-weighted Scan: hypointense signal in L1 3 Pre-procedural sagittal TIRM-weighted Scan: hyperintense signal in L1 4 Post-procedural sagittal TIRM-weighted Scan: hyperintense signal in L1 and discs

4 0 0