Need of vascular surgeon and comparison of value for anterior lumbar interbody fusion (ALIF) in lateral decubitus: Delphi consensus.

BACKGROUND AND PURPOSE: Anterior lumbar approaches are recommended for clinical conditions that require interbody stability, spinal deformity corrections or a large fusion area. Anterior lumbar interbody fusion in lateral decubitus position (LatALIF) has gained progressive interest in the last years. The study aims to describe the current habit, the perception of safety and the perceptions of need of vascular surgeons according to experienced spine surgeons by comparing LatALIF to the standard L5-S1 supine ALIF (SupALIF). METHODS: A two-round Delphi method study was conducted to assess the consensus, within expert spine surgeons, regarding the perception of safety, the preoperative planning, the complications management and the need for vascular surgeons by performing anterior approaches (SupALIF vs LatALIF). RESULTS: A total of 14 experts voluntary were involved in the survey. From 82 sentences voted in the first round, a consensus was reached for 38 items. This included the feasibility of safe LatALIF without systematic involvement of vascular surgeon for routine cases (while for revision cases the involvement of the vascular surgeon is an appropriate option) and the appropriateness of standard MRI to evaluate the accessibility of the vascular window. Thirteen sentences reached the final consensus in the second round, whereas no consensus was reached for the remaining 20 statements. CONCLUSIONS: The Delphi study collected the consensus on several points, such as the consolidated required experience on anterior approaches, the accurate study of vascular anatomy with MRI, the management of complications and the significant reduction of the surgical times of the LatALIF if compared to SupALIF in combined procedures. Furthermore, the study group agrees that LatALIF can be performed without the need for a vascular surgeon in routine cases.

Applied anatomy and surgical technique of the lateral single-position L5-S1 fusion.

The latest development in the anterior lumbar interbody fusion (ALIF) procedure is its application in the lateral position to allow for simultaneous posterior percutaneous screw placement. The technical details of the lateral ALIF technique have not yet been described. To describe the surgical anatomy relevant to the lateral ALIF approach we performed a comprehensive anatomical study. In addition, the preoperative imaging, patient positioning, planning of the skin incision, positioning of the C-arm, surgical approach, and surgical technique are discussed in detail. The technique described led to the successful use of the lateral ALIF technique in our clinical cases. No lateral ALIF procedure needed to be aborted during these cases. Our present work gives detailed anatomical background and technical details for the lateral ALIF approach. This teaching article can provide readers with sufficient technical and anatomical knowledge to assist them in performing their first lateral ALIF procedure.

Trial of Decompressive Craniectomy for Traumatic Intracranial Hypertension.

BACKGROUND: The effect of decompressive craniectomy on clinical outcomes in patients with refractory traumatic intracranial hypertension remains unclear. METHODS: From 2004 through 2014, we randomly assigned 408 patients, 10 to 65 years of age, with traumatic brain injury and refractory elevated intracranial pressure (>25 mm Hg) to undergo decompressive craniectomy or receive ongoing medical care. The primary outcome was the rating on the Extended Glasgow Outcome Scale (GOS-E) (an 8-point scale, ranging from death to "upper good recovery" [no injury-related problems]) at 6 months. The primary-outcome measure was analyzed with an ordinal method based on the proportional-odds model. If the model was rejected, that would indicate a significant difference in the GOS-E distribution, and results would be reported descriptively. RESULTS: The GOS-E distribution differed between the two groups (P<0.001). The proportional-odds assumption was rejected, and therefore results are reported descriptively. At 6 months, the GOS-E distributions were as follows: death, 26.9% among 201 patients in the surgical group versus 48.9% among 188 patients in the medical group; vegetative state, 8.5% versus 2.1%; lower severe disability (dependent on others for care), 21.9% versus 14.4%; upper severe disability (independent at home), 15.4% versus 8.0%; moderate disability, 23.4% versus 19.7%; and good recovery, 4.0% versus 6.9%. At 12 months, the GOS-E distributions were as follows: death, 30.4% among 194 surgical patients versus 52.0% among 179 medical patients; vegetative state, 6.2% versus 1.7%; lower severe disability, 18.0% versus 14.0%; upper severe disability, 13.4% versus 3.9%; moderate disability, 22.2% versus 20.1%; and good recovery, 9.8% versus 8.4%. Surgical patients had fewer hours than medical patients with intracranial pressure above 25 mm Hg after randomization (median, 5.0 vs. 17.0 hours; P<0.001) but had a higher rate of adverse events (16.3% vs. 9.2%, P=0.03). CONCLUSIONS: At 6 months, decompressive craniectomy in patients with traumatic brain injury and refractory intracranial hypertension resulted in lower mortality and higher rates of vegetative state, lower severe disability, and upper severe disability than medical care. The rates of moderate disability and good recovery were similar in the two groups. (Funded by the Medical Research Council and others; RESCUEicp Current Controlled Trials number, ISRCTN66202560 .).

S1 Sacrectomy for Re-recurrent Rectal Cancer: Our Experience with Reconstruction Using an Expandable Vertebral Body Replacement Device.

INTRODUCTION: R0 resection is achieved by high sacrectomy for local recurrence of colorectal cancer, but significant rates of perioperative complications and long-term patient morbidity are associated with this procedure. In this report, we outline our unique experience of using an expandable cage for vertebral body reconstruction following S1 sacrectomy in a 66-year-old patient with re-recurrent rectal cancer. We aim to highlight several key steps, with a view to improving postoperative outcomes. TECHNIQUE: A midline laparotomy was performed with the patient in supine Lloyd-Davies position, demonstrating recurrence of tumor at the S1 vertebral body. Subtotal vertebral body excision of S1 with sparing of the posterior wall and ventral foramina was completed by using an ultrasonic bone aspirator. Reconstruction was performed using an expandable corpectomy spacer system. The system was assembled and expanded in situ to optimally bridge the corpectomy. The device was secured into the L5 and S2 vertebrae by means of angled end plate screws superiorly and inferiorly. Bone grafts were positioned adjacent to the implant after this. RESULTS: Total operating time was 266 minutes with 350 mL of intraoperative blood loss. There were no immediate postoperative complications. The patient did not report any back pain at the time of discharge, and no neurological deficit was reported or identified. Postoperative CT scan showed excellent vertebral alignment and preservation of S1 height. CONCLUSION: We conclude that high sacrectomy with an expandable metal cage is feasible in the context of re-recurrent rectal cancer when consideration is given to the method of osteotomy and vertebral body replacement.

Nanocrystalline hydroxyapatite intervertebral cages induce fusion after anterior cervical discectomy and may be a safe alternative to PEEK or carbon fiber intervertebral cages.

PURPOSE: Nanocrystalline hydroxyapatite (nHA) cages have emerged as a new alternative to carbon fiber or polyether ether ketone (PEEK) devices to promote intervertebral fusion. No evidence has been published to date regarding rates of fusion for these devices after anterior cervical discectomy and fusion (ACDF). METHODS: Eight patients underwent one- or two-level ACDF with nHA intervertebral cages (Nanoss®-Cervical, Pioneer® Surgical Technology, Inc., Marquette, MI). Radiographs, neck disability index (NDI) and visual analog scores (VAS) for pain were taken preoperatively and at a minimum of 19 months postoperatively. RESULTS: At an average follow-up of 21 months, all eight patients (100%) achieved fusion as assessed by plain radiographs. Reduction in preoperative symptomology was comparable to previously published data with a mean reduction of neck VAS of 3, arm VAS of 6 and NDI reduced by 27%. Radiographs showed clear evidence of bridging bone. CONCLUSIONS: This series provides evidence that nHA intervertebral cages can successfully promote fusion after ACDF and may provide an alternative to carbon fiber and PEEK cages.

Anterior cervical discectomy and fusion versus posterior cervical foraminotomy in the treatment of brachialgia: the Leeds spinal unit experience (2008-2013).

BACKGROUND: The surgical management of cervical brachialgia utilising anterior cervical discectomy and fusion (ACDF) or posterior cervical foraminotomy (PCF) is a controversial area in spinal surgery. Previous studies are limited by utilisation of non-validated outcome measures and, importantly, absence of pre-operative analysis to ensure both groups are matched. The authors aimed to compare the effectiveness of ACDF and PCF using validated outcome measures. To our knowledge, it is the first study in the literature to do this. METHODS: The authors conducted a 5-year retrospective review (2008-2013) of outcomes following both the above procedures and also compared the effectiveness of both techniques. Patients with myelopathy and large central discs were excluded. The main outcome variables measured were the neck disability index (NDI) and visual analogue scores (VAS) for neck and arm pain pre-operatively and again at 2-year follow-up. The Wilcoxon signed-rank test and Student t-tests were used to test differences. RESULTS: A total of 150 ACDFs and 51 PCFs were performed for brachialgia. There was no differences in the pre-operative NDI, VAS neck and arm scores between both groups (p > 0.05). As expected, both ACDF and PCF delivered statistically significant improvement in NDI, VAS-neck and VAS-arm scores. The degree of improvement of NDI, VAS-neck and VAS-arm were the same between both groups of patients (p > 0.05) with a trend favouring the PCF group. In the ACDF group, two (1.3 %) patients needed repeat ACDF due to adjacent segment disease. One patient (0.7 %) needed further decompression via a foraminotomy. In the PCF group one (2.0 %) patient needed ACDF due to persistent brachialgia. CONCLUSIONS: We found both interventions delivered similar improvements in the VAS and NDI scores in patients. Both techniques may be appropriately utilised when treating a patient with cervical brachialgia.

Extent of medicolegal burden in neurosurgery - An analysis of the National Health Service Litigation Authority Database.

INTRODUCTION: Neurosurgery remains amongst the highest malpractice risk specialties. We aimed to better understand the medicolegal burden in neurosurgery by analysing a large volume of claims recorded by the National Health Service Litigation Authority (NHSLA). METHODS: The NHSLA database was retrospectively interrogated for all closed (i.e. with legal outcomes) claims in neurosurgery recorded between 1997 and 2011. Collected data included clinical event; subspecialty; patient injury sustained; reason for claim; legal outcome and litigation costs. RESULTS: The total neurosurgical litigation cost associated with 617 closed claims over the time period investigated was £67.4 million. 282 claims (46%) were successful with damages awarded. The annual claim volume and damages paid increased between 2002 and 2011 by 50% and 140%, respectively, and two-thirds of these increases were attributable to spinal claims. 30% of the total litigation cost was legal fees. The leading causes of damages paid in cranial surgery were delayed diagnosis (29%) and delayed treatment (24%). In contrast, the leading causes of damages paid in spinal surgery were delayed diagnosis (32%) and surgical negligence (22%). The greatest mean damages awarded per claim were for brain damage (£617,000), compared to only £51,000 for fatality. CONCLUSION: Neurosurgical litigation in NHS hospitals has significantly increased over the last decade, predominantly due to spinal claims. A neurosurgical claim has a very high likelihood of success, and even for unsuccessful claims, associated legal fees are considerable. Causes of claims are differently distributed between cranial and spinal neurosurgery, although overall, delay to diagnosis accounted for the predominant share of claims volume and damages. There was a significant medicolegal burden associated with serious long-term injury and need for life-long care as in the case of brain damage as compared with death as an outcome. This analysis represents the largest U.K. study on litigation in surgery to date.

Fracture through fused cervical segments following trauma in a patient with Klippel-Feil syndrome.

Klippel-Feil syndrome (KPS) is a congenital spinal deformity characterised by the presence of at least one fused cervical segment. We report an unusual case of a fracture through fused cervical segment in a patient with KPS, who presented with quadriparesis and progressed on to develop respiratory failure and quadriplegia and who had a successful outcome following surgery. To the best of our knowledge, fracture through fused cervical segments in a Klippel-Feil patient has not been reported previously and this case report extends the spectrum of injuries seen in patients with KPS.

24-Month Outcomes of Indirect Decompression Using a Minimally Invasive Interspinous Fixation Device versus Standard Open Direct Decompression for Lumbar Spinal Stenosis: A Prospective Comparison.

Purpose: An early-stage, multi-centre, prospective, randomised control trial with five-year follow-up was approved by Health Research Authority to compare the efficacy of a minimally invasive, laterally implanted interspinous fixation device (IFD) to open direct surgical decompression in treating lumbar spinal stenosis (LSS). Two-year results are presented. Patients and Methods: Forty-eight participants were randomly assigned to IFD or decompression. Primary study endpoints included changes from baseline at 8-weeks, 6, 12 and 24-months follow-ups for leg pain (visual analogue scale, VAS), back pain (VAS), disability (Oswestry Disability Index, ODI), LSS physical function (Zurich Claudication Questionnaire), distance walked in five minutes and number of repetitions of sitting-to-standing in one minute. Secondary study endpoints included patient and clinician global impression of change, adverse events, reoperations, operating parameters, and fusion rate. Results: Both treatment groups demonstrated statistically significant improvements in mean leg pain, back pain, ODI disability, LSS physical function, walking distance and sitting-to-standing repetitions compared to baseline over 24 months. Mean reduction of ODI from baseline levels was between 35% and 56% for IFD (p<0.002), and 49% to 55% for decompression (p<0.001) for all follow-up time points. Mean reduction of IFD group leg pain was between 57% and 78% for all time points (p<0.001), with 72% to 94% of participants having at least 30% reduction of leg pain from 8-weeks through 24-months. Walking distance for the IFD group increased from 66% to 94% and sitting-to-standing repetitions increased from 44% to 64% for all follow-up time points. Blood loss was 88% less in the IFD group (p=0.024) and operating time parameters strongly favoured IFD compared to decompression (p<0.001). An 89% fusion rate was assessed in a subset of IFD participants. There were no intraoperative device issues or re-operations in the IFD group, and only one healed and non-symptomatic spinous process fracture observed within 24 months. Conclusion: Despite a low number of participants in the IFD group, the study demonstrated successful two-year safety and clinical outcomes for the IFD with significant operation-related advantages compared to surgical decompression.

Cauda equina compression post lumbar discography.

Discography is used as an aid in the diagnosis of back pain related to intervertebral disc pathology. It involves attempting to elicit the patient's pain symptoms by injecting contrast into the suspected pathological disc. The overall complication rate of discography is low, with discitis being the most common complication and acute disc herniation post lumbar discography being reported in a small number of cases. We describe the case of a patient who developed cauda equina compression post lumbar discography.

Interspinous distractor devices for the management of lumbar spinal stenosis: a miracle cure for a common problem?

Neurogenic claudication due to lumbar spinal stenosis is the commonest cause of back and leg pain in the elderly. It consumes large amounts of healthcare resource and is a common reason for GP consultations. Surgical management by decompressive laminectomy is the traditional method used for those patients in whom conservative management has failed. However, the advent of minimally invasive interspinous distraction devices, which are designed to alleviate symptoms of neurogenic intermittent claudication without subjecting the patient to a major operation, has potentially revolutionised the management of lumbar spinal stenosis. This review describes the principles of interspinous distraction devices, the rationale for their use in the management of lumbar spinal stenosis, indications and predictors of outcome. Published data on the safety and efficacy of the various devices available is encouraging but long term results are awaited. The superiority of interspinous distraction devices over conservative treatment has already been established, however, the precise indication for this new technology and whether the implants can replace conventional decompressive surgery in some situations has not been clearly defined.

Global neurosurgery amongst the EANS community: Where are we at?

•Awareness of Global Neurosurgery opportunities is limited in the EANS and a minority have had previous experiences with such activities.•Most training programs and job environments don't encourage participation in Global Neurosurgery and mentors are lacking.•However, most European neurosurgeons and trainees remain interested in Global Neurosurgery and are willing to participate.•Junior trainees is the group with the highest rate of interest for Global Neurosurgery.•Barriers exist that may limit participation in Global Neurosurgery, and funding is the most relevant.

Working in low- and middle-income countries: Learning from each other.

•Barriers may limit LMICs-HICs collaborations: infrastructure, equipment's lack/inadequacy, political issues, brain drain.•Local training is crucial for universal health coverage; several activities are headed by Global Neurosurgery organisations.•The â€‹EANS Global and Humanitarian Neurosurgery Committee aims to become a gateway for partnerships between HICs and LMICs.

Evaluation of Outcomes Among Patients With Traumatic Intracranial Hypertension Treated With Decompressive Craniectomy vs Standard Medical Care at 24 Months: A Secondary Analysis of the RESCUEicp Randomized Clinical Trial.

Importance: Trials often assess primary outcomes of traumatic brain injury at 6 months. Longer-term data are needed to assess outcomes for patients receiving surgical vs medical treatment for traumatic intracranial hypertension. Objective: To evaluate 24-month outcomes for patients with traumatic intracranial hypertension treated with decompressive craniectomy or standard medical care. Design, Setting, and Participants: Prespecified secondary analysis of the Randomized Evaluation of Surgery With Craniectomy for Uncontrollable Elevation of Intracranial Pressure (RESCUEicp) randomized clinical trial data was performed for patients with traumatic intracranial hypertension (>25 mm Hg) from 52 centers in 20 countries. Enrollment occurred between January 2004 and March 2014. Data were analyzed between 2018 and 2021. Eligibility criteria were age 10 to 65 years, traumatic brain injury (confirmed via computed tomography), intracranial pressure monitoring, and sustained and refractory elevated intracranial pressure for 1 to 12 hours despite pressure-controlling measures. Exclusion criteria were bilateral fixed and dilated pupils, bleeding diathesis, or unsurvivable injury. Interventions: Patients were randomly assigned 1:1 to receive a decompressive craniectomy with standard care (surgical group) or to ongoing medical treatment with the option to add barbiturate infusion (medical group). Main Outcomes and Measures: The primary outcome was measured with the 8-point Extended Glasgow Outcome Scale (1 indicates death and 8 denotes upper good recovery), and the 6- to 24-month outcome trajectory was examined. Results: This study enrolled 408 patients: 206 in the surgical group and 202 in the medical group. The mean (SD) age was 32.3 (13.2) and 34.8 (13.7) years, respectively, and the study population was predominantly male (165 [81.7%] and 156 [80.0%], respectively). At 24 months, patients in the surgical group had reduced mortality (61 [33.5%] vs 94 [54.0%]; absolute difference, -20.5 [95% CI, -30.8 to -10.2]) and higher rates of vegetative state (absolute difference, 4.3 [95% CI, 0.0 to 8.6]), lower or upper moderate disability (4.7 [-0.9 to 10.3] vs 2.8 [-4.2 to 9.8]), and lower or upper severe disability (2.2 [-5.4 to 9.8] vs 6.5 [1.8 to 11.2]; χ27 = 24.20, P = .001). For every 100 individuals treated surgically, 21 additional patients survived at 24 months; 4 were in a vegetative state, 2 had lower and 7 had upper severe disability, and 5 had lower and 3 had upper moderate disability, respectively. Rates of lower and upper good recovery were similar for the surgical and medical groups (20 [11.0%] vs 19 [10.9%]), and significant differences in net improvement (≥1 grade) were observed between 6 and 24 months (55 [30.0%] vs 25 [14.0%]; χ22 = 13.27, P = .001). Conclusions and Relevance: At 24 months, patients with surgically treated posttraumatic refractory intracranial hypertension had a sustained reduction in mortality and higher rates of vegetative state, severe disability, and moderate disability. Patients in the surgical group were more likely to improve over time vs patients in the medical group. Trial Registration: ISRCTN Identifier: 66202560.

The Isadora syndrome: a case report of cervical, oesophageal and tracheal transection in a go-karting accident.

We report a case of cervical spine, tracheal and oesophageal trauma from a go-karting injury caused by the patient's scarf catching in the vehicle's wheel. We discuss the significance of the pre-hospital and operative management of this potentially life-threatening injury by a multi-specialty surgical team. The importance of health and safety issues in recreational sports is highlighted in view of the increasing incidence of cervical spine trauma over past two decades.

SARS-CoV-2 Infection Induces Psoriatic Arthritis Flares and Enthesis Resident Plasmacytoid Dendritic Cell Type-1 Interferon Inhibition by JAK Antagonism Offer Novel Spondyloarthritis Pathogenesis Insights.

Objective: Bacterial and viral infectious triggers are linked to spondyloarthritis (SpA) including psoriatic arthritis (PsA) development, likely via dendritic cell activation. We investigated spinal entheseal plasmacytoid dendritic cells (pDCs) toll-like receptor (TLR)-7 and 9 activation and therapeutic modulation, including JAK inhibition. We also investigated if COVID-19 infection, a potent TLR-7 stimulator triggered PsA flares. Methods: Normal entheseal pDCs were characterized and stimulated with imiquimod and CpG oligodeoxynucleotides (ODN) to evaluate TNF and IFNα production. NanoString gene expression assay of total pDCs RNA was performed pre- and post- ODN stimulation. Pharmacological inhibition of induced IFNα protein was performed with Tofacitinib and PDE4 inhibition. The impact of SARS-CoV2 viral infection on PsA flares was evaluated. Results: CD45+HLA-DR+CD123+CD303+CD11c- entheseal pDCs were more numerous than blood pDCs (1.9 ± 0.8% vs 0.2 ± 0.07% of CD45+ cells, p=0.008) and showed inducible IFNα and TNF protein following ODN/imiquimod stimulation and were the sole entheseal IFNα producers. NanoString data identified 11 significantly upregulated differentially expressed genes (DEGs) including TNF in stimulated pDCs. Canonical pathway analysis revealed activation of dendritic cell maturation, NF-κB signaling, toll-like receptor signaling and JAK/STAT signaling pathways following ODN stimulation. Both tofacitinib and PDE4i strongly attenuated ODN induced IFNα. DAPSA scores elevations occurred in 18 PsA cases with SARS-CoV2 infection (9.7 ± 4 pre-infection and 35.3 ± 7.5 during infection). Conclusion: Entheseal pDCs link microbes to TNF/IFNα production. SARS-CoV-2 infection is associated with PsA Flares and JAK inhibition suppressed activated entheseal plasmacytoid dendritic Type-1 interferon responses as pointers towards a novel mechanism of PsA and SpA-related arthropathy.

Bradycardia in neurosurgery.

Cushing reflex' is characterized by the occurrence of hypertension, bradycardia and apnoea secondary to raised increased intracranial pressure (ICP), leading to pressure on and or stretch, or both, of the brainstem. With the wide availability of monitoring facilities and advancements in investigation techniques, observation of increased intracranial pressure resulting in haemodynamic instability and bradycardia has been increasingly recognized in relation to many neurosurgical conditions and procedures. The causes of bradycardia include space occupying lesion involving or compressing the brain parenchyma (subdural haematoma, tumours, hydrocephalus), neurosurgical procedures (neuroendoscopy, placement of extradural drains), epileptic and non-epileptic seizures, trigemino-cardiac reflex, cerebellar lesions, spinal lesions (neurogenic shock, autonomic dysreflexia) and many other rare causes (Ventricular catheter obstruction in cases of hydrocephalus, colloid cysts related acute neurogenic cardiac dysfunction, Ondine's curse syndrome, etc.). This highlights that bradycardia can be a warning sign in many neurosurgical conditions and Cushing's reflex is a protective and effective action of the brain for preserving an adequate cerebral perfusion pressure despite an increased intracranial pressure. Management of these patients include identification and treatment of the underlying cause of bradycardia, anti-cholinergics and if necessary cardiac pacing, nevertheless, other causes of haemodynamic changes (i.e. anesthetic drugs, tumor manipulation) should also be considered and managed accordingly. We believe that this knowledge and understanding will help to identify the patients' at risk and will also help in the management of neurosurgical patients with bradycardia.

The biomechanics of vertebroplasty in multiple myeloma and metastatic bladder cancer: a preliminary cadaveric investigation.

OBJECT: The vertebral column is the most common site for secondary bone metastases and lesions arising from hematological malignancies such as multiple myeloma (MM). These infiltrations can be lytic in nature and cause severe weakening of the vertebral body, an increased risk of fracture, and spinal cord compression leading to neurological deficit. Qualitatively it is apparent that increasing infiltration of these lytic lesions will have a deleterious effect on the mechanical behavior of the vertebrae. However, there is little quantitative information about the relationship between tumor deposits and the impact on the mechanical behavior of the vertebrae. In addition, there have been limited biomechanical assessments of the use of vertebroplasty in the management of these malignancies. The purpose of this preliminary study was to evaluate the mechanical behavior of lesion-infiltrated vertebrae from 2 malignant cancers and to investigate the effectiveness of vertebroplasty with and without tumor debulking. METHODS: Individual vertebrae from 2 donor spines--one with MM and another with bone metastases secondary to bladder cancer-were fractured under an eccentric flexion load, from which failure strength and stiffness were derived. Alternate vertebrae defined by spinal level were assigned to 2 groups: Group 1 involved removal of lesion material with Coblation (ArthroCare Corp.) preceding vertebroplasty; Group 2 received no Coblation prior to augmentation. All vertebrae were fractured postaugmentation under the same loading protocol. Micro-CT assessments were undertaken to investigate vertebral morphology, fracture patterns, and cement distribution. RESULTS: Multiple myeloma involvement was characterized by several small lesions, severe bone degradation, and multiple areas of vertebral shell compromise. In contrast, large focal lesions were present in the vertebrae with metastatic bladder cancer, and the shell generally remained intact. The mean initial failure strength of the vertebrae with metastases secondary to MM was significantly lower than in vertebrae with bone metastases secondary to bladder cancer (Load = 950 +/- 300 N vs 2200 +/- 750 N, p < 0.0001). A significant improvement in relative fracture strength was found postaugmentation for both lesion types (1.4 +/- 0.5, p < 0.001). Coblation provided a marginally significant increase in the same parameter postaugmentation (p = 0.08) and qualitatively improved the ease of injection and guidance of cement. CONCLUSIONS: In the vertebral column, metastatic lesions secondary to bladder cancer and MM showed variations in the pattern of infiltration, both of which led to significant reductions in fracture strength. Account should be taken of these differences to optimize the vertebroplasty intervention in terms of the cement formulation, delivery, and any additional surgical procedure.

The biomechanical effectiveness of prophylactic vertebroplasty: a dynamic cadaveric study.

OBJECT: The purpose of the study was to investigate the segmental effects of prophylactic vertebroplasty under increasingly demanding loading conditions and to assess the effect of altered cement properties on the construct biomechanics. METHODS: Twelve human cadaveric 3-vertebral functional spinal units (T12-L2) were prepared such that the intact L-1 vertebra was prophylactically augmented with cements of differing elastic moduli (100, 50, 25, and 12.5% modulus of the base cement). These specimens were subjected to quasistatic subfailure compression pre- and postaugmentation to 50% of the predicted failure strength and then cyclic loading in a fatigue rig (115,000 cycles) to characterize the high-stress, short-cycle fatigue properties of the construct. Loading was increased incrementally in proportion to body weight to a maximum of 3.5 x body weight. Quantitative computed tomography assessment was conducted pre- and postaugmentation and following cyclic testing to assess vertebral condition, cement placement, and fracture classification. RESULTS: Adjacent and periaugmentation fractures were induced in the prophylactically augmented segments. However, it appeared that these fractures mainly occurred when the specimens were subjected to loads beyond those that may commonly occur during most normal physiological activities. CONCLUSIONS: Lowering the elastic modulus of the cement appeared to have no significant effect on the frequency or severity of the induced fracture within the vertebral segment.