[Show abstract][Hide abstract] ABSTRACT: There are a number of drawbacks to incorporating large concentrations of barium sulfate (BaSO4) as the radiopacifier in PMMA-based bone cements for percutaneous vertebroplasty. These include adverse effects on injectability, viscosity profile, setting time, mechanical properties of the cement and bone resorption. We have synthesized a novel cement that is designed to address some of these drawbacks. Its powder includes PMMA microspheres in which gold particles are embedded and its monomer is the same as that used in commercial cements for vertebroplasty. In comparison to one such commercial cement brand, VertaPlex™, the new cement has longer doughing time, longer injection time, higher compressive strength, higher compressive modulus, and is superior in terms of cytotoxicity. For augmentation of fractured fresh-frozen cadaveric vertebral bodies (T6-L5) using simulated vertebroplasty, results for compressive strength and compressive stiffness of the construct and the percentage of the volume of the vertebral body filled by the cement were comparable for the two cements although the radiopacity of the new cement was significantly lower than that for VertaPlex™. The present results indicate that the new cement warrants further study.
[Show abstract][Hide abstract] ABSTRACT: Background: Low back pain (LBP) is a common health problem and a substantial part of LBP is presumed to be attributable to degeneration of the intervertebral disc. For patients suffering from intractable discogenic LBP, there are few evidence-based effective interventional treatment options available. In 2010, the results of a randomized controlled trial (RCT) were published concerning "intradiscal methylene blue injection" (IMBI), in which this intervention appeared to be very successful in relieving discogenic pain. Therefore, we decided to repeat this study to investigate whether we could replicate the published results. The results of our preliminary feasibility study gave reason to set up an RCT. The aim of this RCT is to evaluate if IMBI is a more effective treatment of discogenic low back pain as an intradiscal placebo intervention, and furthermore, to assess the cost-effectiveness of this intervention. Methods/Design: Consecutive discogenic low back pain patients referred to four specialized pain treatment facilities are being screened for eligibility. After a positive standardized provocation discography and informed consent, patients are randomized into two groups. The treatment group receives an intradiscal injection with methylene blue, lidocaine, and contrast, and the control group receives intradiscal isotonic saline with lidocaine and contrast. Main outcome measures are pain at the 6-month follow-up, patient's global impression of change, cost-effectiveness, quality of life, disability, and analgesic intake. Discussion: The importance of this study is emphasized by the fact that for intractable discogenic low back pain patients, evidence-based effective pain treatments are rare. If this study establishes clinical success and cost-effectiveness, IMBI could become the "pain treatment of choice" for a selected group of patients with chronic discogenic low back pain for whom noninvasive treatment options have failed.
[Show abstract][Hide abstract] ABSTRACT: Background:
Calcaneal fractures are associated with substantial morbidity and socioeconomic impact, frequently leading to limited functional outcome and high economic costs. The Oxford foot model (OFM) has been reported as a valid addition to the biomechanical examination of the foot. The aim of our study was to analyze the gait of patients after operative repair of a calcaneal fracture in relation to functional outcome and radiographic findings.
Thirteen patients with a calcaneal fracture underwent gait analysis with OFM at a minimum of six months after open surgery. Intersegmental range of motion was measured during gait. Results were compared with those of healthy subjects and those of patients who had undergone subtalar arthrodesis. Patient-reported questionnaires and radiographic images were also evaluated.
The range of motion between the hindfoot and the tibia in the push-off phase in the transverse plane was significantly correlated with the clinical outcome as reported by patients based on the Foot and Ankle Disability Index (FADI) (r(2) = 0.51; p < 0.001) and the Short Form (SF)-36 physical component summary score (r(2) = 0.52; p < 0.001). We found a significant correlation between the step-off in the subtalar joint as measured on postoperative computed tomography (CT) and range of motion (r(2) = -0.74; p = 0.004). The step-off was also correlated with the patient-reported outcome questionnaire FADI (r(2) = -0.76; p = 0.003) and the SF-36 physical component summary score (r(2) = -0.78; p = 0.002).
This study demonstrated that the subtalar joint range of motion of patients after a calcaneal fracture was related both to the quality of the reduction of the subtalar joint as evaluated on postoperative CT scans and patient-reported functional outcome.
Level of evidence:
Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.
No preview · Article · Nov 2015 · The Journal of Bone and Joint Surgery
[Show abstract][Hide abstract] ABSTRACT: Background context:
The amount of vertebral rotation in the axial plane is of key importance in the prognosis and treatment of adolescent idiopathic scoliosis (AIS). Current methods to determine vertebral rotation are either designed for use in analogue plain radiographs and not useful in digital images, or lack measurement precision and are therefore less suitable for the follow-up of rotation in AIS patients.
To develop a digital X-ray software tool with high measurement precision, to determine vertebral rotation in AIS and to assess its (concurrent) validity and reliability.
Basic science/reliability study using both laboratory and clinical settings.
Software was developed using the algorithm of the Perdriolle torsion meter for analogue AP plain radiographs of the spine. Software was then assessed for (1) concurrent validity and (2) intra- and interobserver reliability. Plain radiographs of both human cadaver vertebrae and outpatient AIS patients were used. Concurrent validity was measured by two independent observers, both experienced in the assessment of plain radiographs. Reliability-measurements were performed by three independent spine surgeons. Departmental funding only - no conflicts of interest.
Pearson's correlation of the software compared to the analogue Perdriolle torsion meter for mid-thoracic vertebrae was 0.98, for low-thoracic vertebrae 0.97 and for lumbar vertebrae 0.97. Measurement exactness of the software was within five degrees in 62% of cases, within ten degrees in 97% of cases. Intraclass Correlation Coefficient (ICC) for inter-observer reliability was 0.92 (0.91-0.95), ICC for intra-observer reliability was 0.96 (0.94-0.97).
We developed a digital X-ray software tool to determine vertebral rotation in AIS with a substantial concurrent validity and reliability, which may be useful for the follow-up of vertebral rotation in AIS patients.
No preview · Article · Sep 2015 · The spine journal: official journal of the North American Spine Society
[Show abstract][Hide abstract] ABSTRACT: Painful pseudarthrosis is one of the most important indications for (revision) surgery after spinal fusion procedures. If pseudarthrosis is the source of recurrent pain it may require revision surgery. It is therefore of great clinical importance to ascertain if it is the source of such pain. The correlation between findings on conventional imaging (plain radiography and CT) and clinical well-being has been shown to be moderate. The goal of this study was to determine the possible role of (18)F-fluoride PET in patients after lumbar spinal interbody fusion by investigating the relationship between PET/CT findings and clinical function and pain.
A cohort of 36 patients was retrospectively included in the study after (18)F-fluoride PET/CT for either persistent or recurrent low back pain (18 patients) or during routine postoperative investigation (18 patients) between 9 and 76 months and 11 and 14 months after posterior lumbar interbody fusion, respectively. Sixty minutes after intravenous injection of 156 - 263 MBq (mean 199 MBq, median 196 MBq) (18)F-fluoride, PET and CT images were acquired using an integrated PET/CT scanner, followed by a diagnostic CT scan. Two observers independently scored the images. The number of bony bridges between vertebrae was scored on the CT images to quantify interbody fusion (0, 1 or 2). Vertebral endplate and intervertebral disc space uptake were evaluated visually as well as semiquantitatively following (18)F-fluoride PET. Findings on PET and CT were correlated with clinical wellbeing as measured by validated questionnaires concerning general daily functioning (Oswestry Disability Index), pain (visual analogue scale) and general health status (EuroQol). Patients were divided into three categories based on these questionnaire scores.
No correlation was found between symptom severity and fusion status. However, (18)F-fluoride activity in the vertebral endplates was significantly higher in patients in the lowest Oswestry Disability Index category (i.e. with the worst clinical performance) than in patients in higher categories (p = 0.01 between categories 1 and 2 and 1 and 3). The visual analogue scale and EuroQol results were similar although less pronounced, with only SUVmax between category 1 and 2 being significantly different (p = 0.04).
We hypothesize that (18)F-fluoride PET/CT may be able to provide support for the diagnosis of painful pseudarthrosis and could serve as a tool to discriminate between symptomatic and asymptomatic pseudarthrosis for revision surgery, as CT defines the consolidation status and PET pinpoints the 'stress reaction' at the vertebral endplates which significantly correlates with Oswestry Disability Index score.
Full-text · Article · Aug 2015 · European Journal of Nuclear Medicine
[Show abstract][Hide abstract] ABSTRACT: An in vitro biomechanical study in porcine thoracic spine segments comparing range of motion in segmental versus multiple nonsegmental UHMWPE sublaminar wire constructs.
To determine the effect of varying instrumentation (wire) density in an UHMWPE sublaminar wire construct for early onset scoliosis (EOS) patients in order to find an optimal wire density which allows maximum growth while still providing adequate correction and fixation.
UHMWPE sublaminar wires in a segmental construct did not negatively affect longitudinal spinal growth over a 24 week period in an ovine model; application in growth guidance system for EOS may therefore be feasible. In order to avoid ectopic bone formation as much as possible, a reduction of instrumented levels, without affecting spinal stabilization, is desirable.
Range of motion (ROM) of nine porcine thoracic spines (T6-T14) was determined in flexion/extension (FE), lateral bending (LB) and axial rotation (AR) up to ±4Nm. Tests were performed for the uninstrumented spine, in a segmental construct with UHMWPE sublaminar wires and dual pedicle screws at the most caudal level, and in four nonsegmental constructs which were attained by stepwise removal of the most caudal wire.
Segmental instrumentation led to a decrease in total ROM by approximately 70% for both FE and LB. A stepwise increase in ROM with decreasing number of consecutively instrumented levels was most clearly observed in LB. However, consistent significant but also relevant substantial differences in ROM for both FE and LB were noted only when comparing two and one consecutively instrumented end levels (P<0.05).
A construct with two consecutive end levels instrumented with UHMWPE sublaminar wires seems to provide the best balance between spinal stabilization and minimizing the number of instrumented levels and thereby surgical exposure, which is crucial for allowing longitudinal growth.
[Show abstract][Hide abstract] ABSTRACT: Background and purpose
We performed a systematic review and a survey in order to (1) evaluate the evidence for the impact of spine registries on the quality of spine care, and with that, on patient-related outcomes, and (2) evaluate the methodology used to organize, analyze, and report the “quality of spine care” from spine registries.
To study the impact, the literature on all spinal disorders was searched. To study methodology, the search was restricted to degenerative spinal disorders. The risk of bias in the studies included was assessed with the Newcastle-Ottawa scale. Additionally, a survey among registry representatives was performed to acquire information about the methodology and practice of existing registries.
4,273 unique references up to May 2014 were identified, and 1,210 were eligible for screening and assessment. No studies on impact were identified, but 34 studies were identified to study the methodology. Half of these studies (17 of the 34) were judged to have a high risk of bias. The survey identified 25 spine registries, representing 14 countries. The organization of these registries, methods used, analytical approaches, and dissemination of results are presented.
We found a lack of evidence that registries have had an impact on the quality of spine care, regardless of whether intervention was non-surgical and/or surgical. To improve the quality of evidence published with registry data, we present several recommendations. Application of these recommendations could lead to registries showing trends, monitoring the quality of spine care given, and ultimately improving the value of the care given to patients with degenerative spinal disorders.
[Show abstract][Hide abstract] ABSTRACT: Background and purpose — Outcome measurement has been shown to improve performance in several fields of healthcare. This understanding has driven a growing interest in value-based healthcare, where value is defined as outcomes achieved per money spent. While low back pain (LBP) constitutes an enormous burden of disease, no universal set of metrics has yet been accepted to measure and compare outcomes. Here, we aim to define such a set.
Patients and methods — An international group of 22 specialists in several disciplines of spine care was assembled to review literature and select LBP outcome metrics through a 6-round modified Delphi process. The scope of the outcome set was degenerative lumbar conditions.
Results — Patient-reported metrics include numerical pain scales, lumbar-related function using the Oswestry disability index, health-related quality of life using the EQ-5D-3L questionnaire, and questions assessing work status and analgesic use. Specific common and serious complications are included. Recommended follow-up intervals include 6, 12, and 24 months after initiating treatment, with optional follow-up at 3 months and 5 years. Metrics for risk stratification are selected based on pre-existing tools.
Interpretation — The outcome measures recommended here are structured around specific etiologies of LBP, span a patient’s entire cycle of care, and allow for risk adjustment. Thus, when implemented, this set can be expected to facilitate meaningful comparisons and ultimately provide a continuous feedback loop, enabling ongoing improvements in quality of care. Much work lies ahead in implementation, revision, and validation of this set, but it is an essential first step toward establishing a community of LBP providers focused on maximizing the value of the care we deliver.
Full-text · Article · Mar 2015 · Acta Orthopaedica
[Show abstract][Hide abstract] ABSTRACT: Study DesignProspective clinical study of intradiscal methylene blue injection for the treatment of lumbar discogenic pain.Objective
The objective of this study was to collect information about efficacy, safety, and acceptability of the intervention, gain and burden of outcome measures, and sample size assumptions for a potential following randomized controlled trial (RCT). If the pilot study demonstrates that this treatment is potentially effective and safe, and the methods and procedures used in this study are feasible, a RCT follows.Summary of Background DataLow back pain (LBP) is a highly common problem with a lifetime prevalence of more than 70%. A substantial part of chronic LBP is attributable to degenerative changes in the intervertebral disc. A recently published RCT assessing the treatment intradiscal injection of methylene blue for chronic discogenic LBP, showed exceptionally good results.Methods
Patients were selected on clinical criteria, magnetic resonance imaging, and a positive provocative discogram. The primary outcome measure was mean pain reduction at 6 months.ResultsFifteen consecutive patients with chronic lumbar discogenic pain enrolled in a multicenter prospective case series in two interventional pain treatment centers in the Netherlands. Six months after the intervention, 40% of the patients claimed at least 30% pain relief. In patients who responded, physical function improved and medication use diminished. We observed no procedural complications or adverse events. Predictors for success were Pfirrmann grading of 2 or less and higher quality of life mental component scores.Conclusions
Our findings of 40% positive respondents, and no complications, give reason to set up a randomized, double-blind, placebo-controlled, trial.
[Show abstract][Hide abstract] ABSTRACT: Background and purpose — We performed a systematic review and a survey in order to (1) evaluate the evidence for the impact of spine registries on the quality of spine care, and with that, on patient-related outcomes, and (2) evaluate the methodology used to organize, analyze, and report the " quality of spine care " from spine registries. Methods — To study the impact, the literature on all spinal disorders was searched. To study methodology, the search was restricted to degenerative spinal disorders. The risk of bias in the studies included was assessed with the Newcastle-Ottawa scale. Additionally, a survey among registry representatives was performed to acquire information about the methodology and practice of existing registries. Results — 4,273 unique references up to May 2014 were identified , and 1,210 were eligible for screening and assessment. No studies on impact were identified, but 34 studies were identified to study the methodology. Half of these studies (17 of the 34) were judged to have a high risk of bias. The survey identified 25 spine registries, representing 14 countries. The organization of these registries, methods used, analytical approaches, and dissemination of results are presented. Interpretation — We found a lack of evidence that registries have had an impact on the quality of spine care, regardless of whether intervention was non-surgical and/or surgical. To improve the quality of evidence published with registry data, we present several recommendations. Application of these recommendations could lead to registries showing trends, monitoring the quality of spine care given, and ultimately improving the value of the care given to patients with degenerative spinal disorders.
[Show abstract][Hide abstract] ABSTRACT: There is still no clear definition of diskogenic low-back pain and no consensus on a generally agreed test, such as provocative diskography (PD), to diagnose painful disk degeneration, and probably more importantly, to predict the outcome of therapy intended to reduce pain that is presumed to be diskogenic in nature. Nevertheless, PD is the most specific procedure to diagnose diskogenic low-back pain. Its accuracy, however, is rather low or at best unknown. Although rare, the most prevalent complication, postdiskography diskitis, can be devastating for the individual patient, so all measures, like strict sterile conditions and antibiotic prophylaxis, should be taken to avoid this complication. It is advised to perform the procedure in a pressure-controlled way with a constant low flow, and optionally computed tomography imaging. PD should not be performed in morphologically normal disks. A standardized execution of the test should be established in order to perform high-quality studies to determine its accuracy to lead to meaningful interventions, and find best practices for diagnosis and treatment of diskogenic back pain. Possibly, PD may have detrimental effects on the disk, causing early degeneration, although it is unknown whether this will be related to clinical symptoms. Especially with these possible adverse side effects in mind, the risk-benefit ratio with the lack of clear benefits from treatments provided, and possible complications of disk puncture, the rationale for PD is questionable, which should be stressed to patients in the process of shared decision making. Diskography as a stand-alone test is not recommended in clinical decision making for patients with chronic low-back pain.
Preview · Article · Dec 2014 · Journal of Pain Research
[Show abstract][Hide abstract] ABSTRACT: In clinical practice, fracture healing is evaluated by clinical judgment in combination with conventional radiography. Due to limited resolution, radiographs don’t provide detailed information regarding the bone micro-architecture and bone strength. Recently, assessment of in vivo bone density, architectural and mechanical properties at the micro-scale became possible using high resolution peripheral quantitative computed tomography (HR-pQCT) in combination with micro finite element analysis (μFEA). So far, such techniques have been used mainly to study intact bone. The aim of this study was to explore whether these techniques can also be used to assess changes in bone density, micro-architecture and bone stiffness during fracture healing. Therefore, the fracture region in eighteen women, aged 50 years or older with a stable distal radius fracture, was scanned using HR-pQCT at 1-2 (baseline), 3-4, 6-8 and 12 weeks post-fracture. At 1-2 and 12 weeks post-fracture the distal radius at the contra-lateral side was also scanned as control. Standard bone density, micro-architectural and geometric parameters were calculated and bone stiffness in compression, torsion and bending was assessed using μFEA. A linear mixed-effect model with time post-fracture as fixed effect was used to detect significant (p-value ≤ 0.05) changes from baseline. Wrist pain and function was scored using the patient-rated wrist evaluation (PRWE) questionnaire. Correlations between the bone parameters and the PRWE score was calculated by Spearman’s correlation coefficient. At the fracture site, total and trabecular bone density increased by 11% and 20%, respectively, at 6-8 weeks, whereas cortical density was decreased by 4%. Trabecular thickness increased by 23-31% at 6-8 and 12 weeks and the intertrabecular area became blurred, indicating intertrabecular bone formation. Compared to baseline, calculated bone stiffness in compression, torsion and bending were increased by 31% after 12 weeks. A moderate negative correlation was found between the stiffness and the PRWE score. No changes were observed at the contra-lateral side. The results demonstrate that it is feasible to assess clinically relevant and significant longitudinal changes in bone density, micro-architecture and mechanical properties at the fracture region during the healing process of stable distal radius fractures using HR-pQCT.