Extraforaminal Lumbar Disk Herniations Lead To Neuroplastic Changes: a Study Using Quantitative Sensory Testing.

INTRODUCTION: Extraforaminal lumbar disk herniations are characterized by distinct clinical features in comparison to paramedian lumbar disk herniations. METHODS: We applied the quantitative sensory testing (QST) protocol of the German Research Network on Neuropathic Pain in 63 patients with a single lumbar disk herniation. They were categorized in 2 groups: (I) an intraspinal (group I; n = 47, 75%) and an extraforaminal (group E; n = 16, 25%). RESULTS: The wind-up ratio for assessing endogenous pain-modulating pathways was higher in group E (2.9 ± 2) than in group I (1.4 ± 1; P = 0.021). After a subsequent series of pinprick stimuli, an increase in pain assessed by the numeric rating scale could be shown in group E (2.1 ± 2 vs 1.1 ± 1; P = 0.032). DISCUSSION: Extraforaminal compression is associated with chronic as well as neuropathic pain, presumably caused by direct compression of the dorsal root ganglion, which may preferentially promote specific chronic pain mechanisms. Muscle Nerve 58: 676-680, 2018.

The value of quantitative sensory testing in spine research.

The improvement of pain and functionality is the major goal of a surgical intervention. Thus, the purpose of the present prospective study was to evaluate whether subjective sensory deficits in patients with lumbar radiculopathy caused by a lumbar disc herniation are related to clinical status, using several outcome scores and the quantitative sensory testing (QST) pre- and 12 months postoperatively. We applied the QST in 52 patients with a single lumbar disc herniation treated by lumbar sequestrectomy pre- and 12 months postoperatively. Further evaluation included numeric rating scale (NRS) for leg, EuroQoL-5D (EQ-5D), Core Outcome Measure Index (COMI), Oswestry Disability Index (ODI), Beck Depression Inventory (BDI) and PaindDetect questionnaire (PD-Q). Patients were then categorized into two groups based on their subjective recovery of sensory function. The patients' self-assessment and QST were correlated with each other for the pre- and postoperative visit after 12 months. The two groups showed postoperative differences in mechanical and vibration detection threshold as well as in the postoperative PD-Q (p < 0.005). Multidimensional scores did not consistently match the QST parameters in patients with a lumbar disc herniation. Commonly used clinical scores in spine research show low or no correlation with QST. Nevertheless, mechanical thresholds seem to play an important role to detect and follow up a sensory deficit investigated by QST.

Preoperative sport improves the outcome of lumbar disc surgery: a prospective monocentric cohort study.

A lumbar disc herniation resulting in surgery may be an incisive event in a patient's everyday life. The patient's recovery after sequestrectomy may be influenced by several factors. There is evidence that regular physical activity can lower pain perception and improve the outcome after surgery. For this purpose, we hypothesized that patients performing regular sports prior to lumbar disc surgery might have less pain perception and disability thereafter. Fifty-two participants with a single lumbar disc herniation confirmed on MRI treated by a lumbar sequestrectomy were included in the trial. They were categorized into two groups based on their self-reported level of physical activity prior to surgery: group NS, no regular physical activity and group S, with regular physical activity. Further evaluation included a detailed medical history, a physical examination, and various questionnaires: Visual Analog Scale (VAS), Beck-Depression-Inventory (BDI), Oswestry Disability Index (ODI), Core Outcome Measure Index (COMI), and the EuroQoL-5Dimension (EQ- 5D). Surgery had an excellent overall improvement of pain and disability (p < 0.005). The ODI, COMI, and EQ-5D differed 6 months after intervention (p < 0.05) favoring the sports group. Leg and back pain on VAS was also significantly less in group B than in group A, 12 months after surgery (p < 0.05). Preoperative regular physical activity is an important influencing factor for the overall satisfaction and disability after lumbar disc surgery. The importance of sports may have been underestimated for surgical outcomes.

Gender differences after lumbar sequestrectomy: a prospective clinical trial using quantitative sensory testing.

BACKGROUND: Quantitative sensory testing (QST) gained popularity to evaluate the time course of recovery in sensory dysfunction and the results of different treatment options. Concerning sex differences in lumbar spine surgery, female gender seems to play a major role as a negative prognostic factor in different spinal disorders. For this purpose, we hypothesised that there are also comparable differences in pain patterns in men and women after lumbar sequestrectomy using QST. METHODS: We applied the QST protocol of the German Research Network on Neuropathic Pain in 53 patients (21 women and 32 men) with a single lumbar disc herniation confirmed on MRI treated by a lumbar sequestrectomy. Further evaluation included a detailed medical history, a physical examination, and various questionnaires: Beck-Depression-Inventory, Oswestry Disability Index, Core Outcome Measure Index, painDETECT-Questionnaire and EQ-5D thermometer. RESULTS: Our analyses showed lower heat thresholds in females preoperatively, that adjusted to that of males 1 week postoperatively. Pressure pain thresholds were lower in women as well, but differed between genders throughout the study. Vibration perception deficits resolve earlier in female than in male patients. Both, women and men, had an excellent overall improvement, postoperatively. CONCLUSION: Our results clearly revealed pre- and postoperative differences in pain perception between genders. These differences have to be taken into account in the evaluation of outcome between genders. Therefore, QST seems to be a good method to evaluate the time course of recovery after surgery.

Improvement of sensory function after sequestrectomy for lumbar disc herniation: a prospective clinical study using quantitative sensory testing.

BACKGROUND: Previous studies have investigated sensory recovery in patients with lumbar disc herniation using rather subjective methods. There have been no reports on changes of sensory function in patients suffering from a preoperative sensory deficit using quantitative sensory testing (QST). The aims of this prospective study were (1) to assess the recovery of preoperative sensory dysfunction after lumbar sequestrectomy and (2) to quantify the strength of relationship between a sensory deficit and the patient's quality of life. METHODS: We applied the QST protocol of the German Research Network on Neuropathic Pain (DFNS) in fifty-two patients with a single lumbar disc herniation confirmed on MRI treated by lumbar sequestrectomy. Further evaluation included a detailed medical history, a physical examination, numeric rating scale for leg, EQ-5D questionnaire, and thermometer. RESULTS: Disc surgery resulted in a significant reduction of leg pain and a significant gain of quality of life. Thermal, mechanical, and vibration perception thresholds showed an obvious side-to-side difference preoperatively (p < 0.005). An early recovery of mechanical and vibration perception thresholds was detected, whereas cold perception needed more than 6 months to recover (p < 0.05). Quality of life was independent from perception thresholds, but correlated significantly with pain reduction. CONCLUSION: Our data clearly show that there is a subjective and quantifiable improvement in sensory dysfunction postoperatively. The current data suggest that a sensory dysfunction does not influence a patient's quality of life.

Reciprocal communication of pericoronary adipose tissue and coronary atherogenesis.

OBJECTIVE: Pericoronary adipose tissue (PCAT) has been linked to underlying coronary artery disease (CAD) and proposed to modulate adjacent atherosclerotic plaque formation over pro-inflammatory pathways. In vitro and ex vivo studies support the bilateral communication of adipose tissue and vessel wall. We quantified PCAT and its dynamics in a low coronary risk cohort with a semi-automated software in serial coronary computed tomography angiography (CTA). METHODS: We retrospectively included patients from a tertiary care hospital who underwent serial coronary CTA with a low cardiovascular risk profile. All examinations were evaluated in a standardized approach: epicardial adipose tissue (EAT) volume and attenuation was quantified in total, in the atrioventricular (RCA, LCX) or interventricular (LAD) sulcus and within a 5 mm radius for each coronary artery (PCAT). Coronary plaques were quantified using a semi-automated software and compared for progression, stability or regression. RESULTS: Of 120 patients (27% females), 59.2% showed atherosclerotic plaques. After 36 months mean follow-up, 22 (18.3%) showed plaque regression, 39 (32.5%) were stable and 49 (40.8%) were progressive. Total EAT volume decreased by -15.6 ±â€¯37.2 mm³ in the regressive group, increased by 2.7 ±â€¯30.6 mm³ in the stable group and by 24.3 ±â€¯37.1 mm³ in the progressive group (p = 0.003). Per-vessel analysis showed a significant decrease of PCAT attenuation in patients with CAD regression (-3.8 ±â€¯7.6HU) compared to the stable (1.2 ±â€¯9.1HU) and progressive group (3.5 ±â€¯8.2HU, p < 0.0001). Mean sulcus EAT attenuation did not show a significant change (p = 0.135). CONCLUSION: Epicardial adipose tissue volume is mutually changing with the progression or regression of coronary artery disease. Perivascular but not epicardial attenuation levels correlate to adjacent plaque and support a direct bilateral influence.

Clinical Outcome Following Surgical Repair of Small Versus Large Orbital Floor Fractures Using Polyglactin 910/Polydioxanone (Ethisorb®).

The aim of this retrospective study was to evaluate the clinical outcome of surgical management of small versus large, isolated orbital floor fractures (OFFs) using polyglactin 910/polydioxanone (Ethisorb®). Covering a four-year period (2010-2013), all records concerning midfacial fractures with involvement of the orbit were screened. Isolated fractures of the orbital floor as well as combined injuries of the orbital floor and medial wall that had been treated surgically using polyglactin 910/polydioxanone (Ethisorb®) were included. Patients underwent a preoperative, a postoperative, and a late ophthalmologic assessment. The clinical outcomes of surgically managed small OFFs up to 2 cm2 were statistically analyzed and compared to clinical results in larger defects. The final sample included 61 patients (25 women, 36 men). Fractures up to 2 cm2 were found in 33 patients (54.1%), whereas 28 patients (45.9%) suffered from OFFs larger than 2 cm2. The clinical outcomes did not significantly differ between both sample categories, and statistical analysis showed a power of 0.91 to detect a potentially existing difference. On final examination, 52 patients were free of any clinical symptoms, whereas minor issues were found in seven subjects, and two patients suffered from severe impairment. In conclusion, polyglactin 910/polydioxanone (Ethisorb®) seems to be a suitable material for surgical repair of both small and large OFFs.

Diagnostic Potential of Multimodal MRI Markers in Atypical Parkinsonian Disorders.

BACKGROUND: The diagnostic potential of multimodal MRI approaches to discriminate among progressive supranuclear palsy (PSP), Parkinson variant of multiple system atrophy (MSA-P) and Parkinson's disease (PD) has not been well investigated. OBJECTIVE: To identify disease-specific neurodegenerative patterns and evaluate the diagnostic accuracy of dedicated MRI, iron concentration (R2*), microstructural integrity (mean diffusivity; MD and fractional anisotropy; FA) as well as volumes were analyzed in patients with PSP, MSA-P and PD. METHODS: 3T MRI of 18 PSP and 16 MSA-P patients were compared with 16 PD patients matched for age and disease duration as well as 21 healthy controls. Statistical parametric mapping (SPM) was applied to objectively identify focal MRI changes throughout the whole-brain. Following dimensionality reduction of significant and multiple comparison-corrected SPM clusters through principal component analysis (PCA), stepwise receiver-operating characteristic curve analysis (ROC) was applied to determine the diagnostic potential of multimodal MRI parameters. RESULTS: PCA revealed two components involving multiple regions identified from SPM analysis. The first component was primarily composed of the mean MD value of the thalamus and the mean MD and FA values of the dentatorubrothalamic tract and the corpus callosum. The second component mainly consisted of mean MD and FA values of the middle cerebellar peduncle. ROC analysis showed 92% of PSP patients were differentiated correctly from MSA-P and PD and 80% of MSA-P patients could be distinguished from PD. CONCLUSION: Multimodal MRI improved the detection of disease-specific neurodegenerative patterns in PSP and MSA-P and highlights its potential to improve the diagnostic accuracy of atypical parkinsonian disorders.

Influence of vitamin K antagonists and direct oral anticoagulation on coronary artery disease: A CTA analysis.

OBJECTIVE: Vitamin K antagonists (VKA) are associated with increased vascular calcification which may lead to an elevated cardiovascular risk. If the direct anticoagulants (DOACs) have similar negative vascular effects is unknown. We evaluated the influence of different anticoagulation strategies on coronary artery disease (CAD) using coronary computed tomography angiography (CTA). METHODS: Overall 702 consecutive patients with non-valvular atrial fibrillation (AF) who underwent CTA for AF ablation planning were enrolled and stratified according to their anticoagulation into VKA, DOAC (all agents) and a control group without oral anticoagulation. Patients were propensity score matched 1:1:1, significant structural heart disease and comorbidities were excluded. CT images were evaluated for plaque burden (calcium score, segment involvement score (SIS) and non-calcified SIS, stenosis grading) and plaque morphology (high risk plaque features: low attenuation, positive remodeling, napkin-ring sign, spotty calcification). RESULTS: Final analysis included 303 patients (101 patients each group) and showed increased overall plaque burden in patients using VKA compared to DOAC users and the control group (mean affected segments 2.58 vs 1.58 vs 2.100, p = 0.008), and a higher prevalence of high-risk plaque (HRP) features (42.6% vs 13.9% vs 26.7%, p < 0.0001). Patients treated with DOACs did not differ in conventional CT findings from the control group and showed an even lower prevalence of selected HRP features compared to the control group: low-attenuation plaques (4.0% vs. 14.4%, p = 0.014) and napkin-ring sign (0 vs. 5.0%, p = 0.029). CONCLUSION: Vitamin K antagonists are associated with a higher plaque burden and increased high-risk plaque features, whereas DOACs may yield a benefit in cardiovascular atherosclerosis.

Clinical and radiological effect of medialized cortical bone trajectory for lumbar pedicle screw fixation in patients with degenerative lumbar spondylolisthesis: study protocol for a randomized controlled trial (mPACT).

BACKGROUND: Spinal fusion with pedicle screw fixation represents the gold standard for lumbar degenerative disc disease with instability. Although it is an established technique, it is nevertheless an invasive intervention with high complication rates. Therefore, minimally invasive approaches have been developed, the medialized bilateral screw pedicel fixation (mPACT) being one of them. The study objective is to evaluate prospectively the efficacy and safety of the mPACT technique compared with the traditional trajectory for degenerative lumbar spondylolisthesis. METHODS/DESIGN: This is a single-center, randomized, controlled, parallel group, superiority trial. A total of 154 adult patients are allocated in a ratio of 1:1. Sample size and power calculation were performed to detect the minimal clinically important difference of 10%, with an expected standard deviation of 20% in the primary outcome parameter, the Oswestry Disability Index, with power of 80%, based on an assumed maximal dropout rate of 20%. Secondary outcome parameters include the EuroQoL 5-Dimension questionnaire, the Beck Depression Inventory, the painDETECT questionnaire and the "timed up and go" test. Furthermore, radiological and health economic outcomes will be evaluated. Follow up is performed until 5 years after surgery. Major inclusion criteria are lumbar degenerative spondylolisthesis with Meyerding grade I or II, which qualifies for decompression and fusion by medialised posterior screw placement with cortical trajectory (mPACT) or by a traditional trajectory for lumbar pedicle screw placement. DISCUSSION: This trial will contribute to the understanding of the short-term and long-term clinical and radiological postoperative course in patients with lumbar degenerative disc disease, in which the mPACT technique is used. TRIAL REGISTRATION: ISRCTN registry, ISRCTN99263604 . Registered on 3 November 2016.

Diagnostic potential of dentatorubrothalamic tract analysis in progressive supranuclear palsy.

BACKGROUND: The differentiation of progressive supranuclear palsy-parkinsonism (PSP-P) from Parkinson's disease (PD) remains a major clinical challenge. OBJECTIVES: To evaluate the diagnostic potential of observer-independent assessments of microstructural integrity within infratentorial brain regions to differentiate PSP-Richardson's syndrome (PSP-RS), PSP-P and PD. METHODS: 3T MRI parameters of mean diffusivity, fractional anisotropy, grey and white matter volumes from patients with PSP-RS (n = 12), PSP-P (n = 12) and mean disease duration of 2.4 ±â€¯1.7 years were compared with PD patients (n = 20) and healthy controls (n = 23) by using statistical parametric mapping and the spatially unbiased infratentorial template. Subsequently MRI measurements of the dentatorubrothalamic tract were determined observer-independently by a validated probabilistic infratentorial atlas. The impairment of gait and postural stability was evaluated by a sum-score derived from the Unified Parkinson Disease Rating Scale. RESULTS: Significant mean diffusivity increases, fractional anisotropy decreases and corresponding volume loss were localized in mesencephalic tegmentum, superior cerebellar peduncle, decussation of superior cerebellar peduncle and dentate nucleus in PSP-RS and PSP-P compared to PD and healthy controls. Altered microstructural integrity of the dentatorubrothalamic tract in PSP-RS was significantly more pronounced compared to PSP-P and correlated significantly with the gait and postural stability sum-score. Linear discriminant analysis identified diffusion tensor imaging measures of the dentatorubrothalamic tract and the gait and postural stability sum-score to classify correctly 95.5% of PRP-RS, PSP-P and PD patients. CONCLUSIONS: Observer-independent analysis of microstructural integrity within the dentatorubrothalamic tract in combination with assessments of gait and postural stability differentiate PSP-P from PSP-RS and PD in early to moderately advanced stages.

Effects of Hyperthyroidism on Coronary Artery Disease: A Computed Tomography Angiography Study.

BACKGROUND: Changes in thyroid hormone concentration can negatively affect the cardiovascular system. Subclinical hyperthyroidism has been linked to an increase of cardiovascular heart disease, however, clinical effects and significance are still uncertain. Therefore, we analyzed coronary computed tomography angiographies of patients with overt and subclinical hyperthyroidism for quantitative parameters and plaque morphology. METHODS: Seven hundred forty-four (47.1% female) patients who underwent coronary computed tomography angiography were stratified into 3 groups: 51 patients with overt, 74 patients with subclinical hyperthyroidism, and 619 patients with euthyroidism. Analysis included grades of stenosis (no stenosis = 0, mild < 50%, intermediate 50%-70%, or high-grade > 70%) and plaque types (noncalcified, mixed, and calcified), segment involvement score (SIS), noncalcified SIS, and high-risk plaque features (napkin ring sign, low attenuation plaque, spotty calcifications, positive remodelling). RESULTS: Patients with overt and subclinical hyperthyroidism had more high-grade stenoses (39.2% vs 37.8% vs 24.2%; P = 0.007) and a higher coronary calcium score (456.5 vs 199.5 vs 155.9; P < 0.0001). Also, a total higher plaque burden has been found (SIS: 3.3 vs 3.2 vs 2.2; P < 0.0001; noncalcified SIS (1.2 vs 1.1 vs 0.6; P < 0.0001)). Patients with overt hyperthyroidism, followed by those with subclinical hyperthyroidism, had the most high-risk plaque features: napkin ring (21.6% vs 9.5% vs 6.0%, P < 0.0001), low attenuation plaque (35.3% vs 27% vs 8.7%, P < 0.0001), spotty calcification (35.3% vs 18.9% vs 19.1%, P = 0.02), and positive remodelling (37.3% vs 37.8% vs 25.5%, P = 0.02). After a mean follow-up of 168 months, significantly more revascularizations were documented for hyperthyroid patients. CONCLUSIONS: Patients with subclinical and overt hyperthyroidism showed more high-grade coronary stenoses, plaque burden, and high-risk plaque features than patients with euthyroidism, which indicates that an increase of thyroid hormones might lead to coronary vascular degeneration and plaque instability.

The influence of surface EMG-triggered multichannel electrical stimulation on sensomotoric recovery in patients with lumbar disc herniation: study protocol for a randomized controlled trial (RECO).

BACKGROUND: Intervertebral disc degeneration is one of the most common reasons for chronic low back pain and sensomotoric deficits, often treated by lumbar sequestrectomy. Nevertheless, the prognostic factors relevant for time and quality of recovery, of the surgical procedure, relative to conservative treatment, remain controversial and require further investigation. Surface electrical stimulation (SES) may be an influential intervention, already showing positive impact on motor and sensory recovery in different patient groups. Since mechanisms of SES still remain unclear, further inquiry is needed. METHODS/DESIGN: This is a prospective, monocentric, randomized, controlled clinical trial. A total of 80 adult patients suffering from a lumbar disc herniation (LDH; 40 treated surgically, 40 conservatively) are allocated in a ratio of 1:1. Patients in the treatment group will receive surface electromyography (EMG)-triggered electrical stimulation for eight weeks, whereas patients in the control group will not obtain any additional treatment. The primary outcome parameter is defined as the cold detection threshold (CDT), determined by quantitative sensory testing (QST), 24 months after intervention. Secondary outcome parameters include the inquiry of sensory nerve function by two-point discrimination and QST, the assessment of motor nerve function by manual muscle testing, and validated scales and scores. These include: the Oswestry Disability Index (ODI) and the Core Outcome Measures Index (COMI) assessing the domains pain, back-specific function, work disability, and patient satisfaction; the EQ-5D investigating the patient's generic health status; the painDETECT questionnaire (PD-Q) to identify neuropathic pain components; and the Beck Depression Inventory (BDI) to assess severity of depression. Moreover, neurological status, pain medication usage, and blood samples (CRP, TNFα, IL-1ß, IL-6) will be evaluated. Study data generation (study site) and data storage, processing, and statistical analysis are clearly separated. DISCUSSION: The results of the RECO study will detect the effect of EMG-triggered multichannel SES on the improvement of mechanical and thermal sensitivity and the effect on motor recovery and pain, associated with clinical and laboratory parameters. Furthermore, data comparing surgical and conservative treatment can be collected. This will hopefully allow treatment recommendations for patients with LDH accompanied by a sensomotoric deficit. TRIAL REGISTRATION: ISRCTN, ISRCTN12741173 . Registered on 15 January 2017.

Gender Influences Radicular Pain Perception in Patients with Lumbar Disc Herniation.

BACKGROUND: Previous studies have demonstrated gender differences in pain perception in quantitative sensory testing. Thus, we hypothesized that there are differences in men and women with lumbar disc herniation awaiting lumbar sequestrectomy. To elucidate the differences in pain perception between men and women, we carried out a prospective clinical monocentric trial using quantitative sensory testing. METHODS: With institutional ethical approval, patients with radiculopathy awaiting lumbar sequestrectomy were examined the day before surgery. Preoperative pain was assessed using quantitative sensory testing and a series of questionnaires including Beck Depression Inventory and a numeric rating scale (NRS) for back and leg pain. Statistical analysis was performed using the Kolmogorov-Smirnov test for normal distribution. The unpaired Student's t-test, Mann-Whitney U test, and Fisher's exact test were used to analyze intergroup differences in the clinical and demographic characteristics and in clinical outcome variables. RESULTS: Fifty patients (20 women and 30 men) were included in the study. The groups did not differ in NRS for back and leg pain. Heat and pressure pain thresholds were found to be lower in women than in men (p≤0.05). Subgroup analyses revealed decreased wind-up ratio in male patients with prior periradicular steroid application (p≤0.05). CONCLUSIONS: Our results clearly indicate that sex differences in pain perception not only exist in healthy subjects, but also in patients with lumbar disc herniation. Therefore, it is essential to provide different treatment modalities to women and men.