Degenerative joint disease of the spine

Perspective on Intradiscal Therapies for Lumbar Discogenic Pain: State of the Science, Knowledge Gaps, and Imperatives for Clinical Adoption

Specific clinical diagnostic criteria have established a consensus for defining patients with lumbar discogenic pain. However, if conservative medical management fails, these patients have few treatment options short of surgery involving discectomy often coupled with fusion or arthroplasty. There is a rapidly-emerging research effort to fill this treatment gap with intradiscal therapies that can be delivered minimally-invasively via fluoroscopically guided injection without altering the normal anatomy of the affected vertebral motion segment. Viable candidate products to date have included mesenchymal stromal cells, platelet-rich plasma, nucleus pulposus structural allograft, and other cell-based compositions. The objective of these products is to repair, supplement, and restore the damaged intervertebral disc as well as retard further degeneration. In doing so, the intervention is meant to eliminate the source of discogenic pain and avoid surgery. Methodologically rigorous studies are rare, however, and based on the best clinical evidence, the safety as well as the magnitude and duration of clinical efficacy remain difficult to estimate. Further, we summarize the US Food and Drug Administration's (FDA) guidance regarding the interpretation of the minimal manipulation and homologous use criteria, which is central to designating these products as a tissue or as a drug/device/biologic. We also provide perspectives on the core evidence and knowledge gaps associated with intradiscal therapies, propose imperatives for evaluating effectiveness of these treatments and highlight several new technologies on the horizon.

Beyond Anatomy: Fat-Suppressed MR and Molecular Imaging of Spinal Pain Generators

Spine pain is highly prevalent and costly, but evaluation with clinical features and anatomic imaging remain limited. Fat-suppressed MR imaging and molecular imaging (MI) may help identify inflammatory, lesional, and malignant causes. Numerous MI agents are available, each with advantages and disadvantages. Herein, FDG PET, prostate-specific membrane antigen (PSMA), bone radiotracers, and others are highlighted. No specific pain MI agents have been identified, but mechanisms of key agents are shown in video format, and the mechanism of PSMA as a theranostic agent is displayed. A multidisciplinary approach is needed to master this topic.

Non-spinal low back pain: Global epidemiology, trends, and risk factors

Background and Aims

Low back pain (LBP) is one of the most debilitating and prevalent disorders. The prevalence of LBP ranges from 30% to 80%, depending on the population, and increases with age. Causes of LBP are typically classified as spinal and non-spinal. The main goal of this study was to investigate the non-spinal causes of LBP, since neglecting these factors leads to increases in the financial, psychological, and physical burden of LBP on individuals as well as on society.

Methods

The data were extracted after searching the PubMed database and Google Scholar search engine up to October 27, 2021. We included all studies that were conducted on a human population and assessed the effects of epidemiological, biological, psychological, and sociodemographic factors on the incidence or progression of LBP.

Results

The most common causes of non-spinal LBP were diseases such as nephrolithiasis, endometriosis, tumors, fibromyalgia, and conditions like psychological disorders and pregnancy. Nevertheless, the perceived intensity of the pain can be affected by factors such as socioeconomic level, genetics, age, habits, diet, and psychological status.

Conclusion

The epidemiology, etiologies, and risk factors associated with LBP should be more clearly recognized to better prevent, diagnose, and treat the underlying disease and to reduce the burden of LBP.

Defining the Patient with Lumbar Discogenic Pain: Real-World Implications for Diagnosis and Effective Clinical Management

There is an enormous body of literature that has identified the intervertebral disc as a potent pain generator. However, with regard to lumbar degenerative disc disease, the specific diagnostic criteria lack clarity and fail to capture the primary components which include axial midline low back pain with or without non-radicular/non-sciatic referred leg pain in a sclerotomal distribution. In fact, there is no specific ICD-10-CM diagnostic code to classify and define discogenic pain as a unique source of pain distinct from other recognized sources of chronic low back pain including facetogenic, neurocompressive including herniation and/or stenosis, sacroiliac, vertebrogenic, and psychogenic. All of these other sources have well-defined ICD-10-CM codes. Corresponding codes for discogenic pain remain absent from the diagnostic coding vernacular. The International Society for the Advancement of Spine Surgery (ISASS) has proposed a modernization of ICD-10-CM codes to specifically define pain associated with lumbar and lumbosacral degenerative disc disease. The proposed codes would also allow the pain to be characterized by location: lumbar region only, leg only, or both. Successful implementation of these codes would benefit both physicians and payers in distinguishing, tracking, and improving algorithms and treatments for discogenic pain associated with intervertebral disc degeneration.

Association of Hallux Valgus with Degenerative Spinal Diseases: A Population-Based Cohort Study

Background: Although hallux valgus is known to cause lower-back pain, the association between hallux valgus and spinal degenerative disease remains unclear. Methods: A retrospective cohort study was conducted between 1 January 2000 and 31 December 2015 using data from the Longitudinal Health Insurance Database in Taiwan. After propensity score matching for age, sex, and some potential comorbidities, 1000 individuals newly diagnosed with hallux valgus were enrolled in the study group, while 1000 individuals never diagnosed with hallux valgus served as the control group. Both groups were followed up until 2015 to evaluate the incidence of hallux valgus. Kaplan-Meier analysis was used to determine the cumulative incidence of hallux valgus, while the Cox proportional hazard model was adopted to estimate the hazard ratio (HR) and adjusted hazard ratio (aHR) with 95% confidence intervals (CIs). Results: The incidence densities of spinal degeneration in the hallux valgus and non-hallux valgus groups were 73.10 and 42.63 per 1000 person-years, respectively. An increased risk of spinal degenerative changes was associated with hallux valgus (adjusted HR = 1.75, 95% CI = 1.50−2.05). Age- and sex-stratified analyses showed a significantly higher risk of spinal degeneration in the hallux valgus group. Moreover, sub-outcome evaluations revealed significantly higher risks of spondylosis (aHR = 2.01, 95% CI = 1.55−2.61), intervertebral disorder (aHR = 2.27, 95% CI = 1.62−3.17), and spinal stenosis (aHR = 1.24, 95% CI = 1.47−1.76). There was also an increased risk of spinal degenerative change in those with hallux valgus without surgical intervention (aHR = 1.95, 95% CI = 1.66−2.99, p < 0.001). Conclusions: Hallux valgus was associated with increased risk of degenerative spinal changes and other spinal disorders.

The effectiveness of bone scintigraphy in the management of low back pain

BACKGROUND

Back and low back pain have been reported as one of the leading causes of activity restriction. While degenerative changes in the spine are among the common causes of low back pain, zygapophyseal (facet) joint pain is seen as the most widely accepted cause of back pain. Standard imaging modalities may have low predictive value in detecting the source of back pain. Thanks to radionuclide bone scintigraphy, painful lesions can be distinguished from age-related changes, especially in patients with chronic low back pain. In this study, we aimed to retrospectively evaluate the clinical results of facet-induced low back pain, which was confirmed by bone scintigraphy, after facet injection treatment.

METHODS

We completed a retrospective review of patients who underwent diagnostic radionuclide bone scintigraphy imaging for low back pain at our institution from 2019 to 2021. Scintigraphy imaging was often performed in conjunction with traditional diagnostic imaging. The patients underwent injection at the levels that were decided by the referring physician on the basis of the clinical symptoms, the physical examination findings, and findings on existing radiologic images, with performance of bone scanning.

RESULTS

The patients consisted of 24 (47.1 %) males and 27 (52.9 %) females with a mean age of 44.03 ± 9.26 years (range 34-67 years) at initial symptom onset. In the bone scintigraphy, increased radioactive uptake was detected in the facet joints of the lumbar region in 33 of 51 (64.7 %) patients. Statistically significant improvement was found in VAS-ODI and SF-36 scorings in 30 patients (90.1 %) after injection in patients with increased radioactive uptake. Statistically significant improvement was found in VAS-ODI and SF-36 scorings in 12 (66.6 %) patients who had no pathological findings with imaging modalities and were injected according to physical examination. When the two groups were compared with each other, the success rate in the group with increased radioactive uptake was found to be statistically significantly higher (p < 0.01) CONCLUSIONS: Application of this technology may lead to more reliable diagnosis and treatment of painful facet arthropathy. Appropriate diagnostic tests and determination of spinal level localization will provide satisfactory results with correct patient selection.

Development of a novel model of intervertebral disc degeneration by the intradiscal application of monosodium iodoacetate (MIA) in rat

BACKGROUND CONTEXT

Low back pain is one of the most common musculoskeletal disorders. Although, the pathology of intervertebral disc (IVD) degeneration has been modeled using various biological methods, these models are inadequate for simulating similar pathologic states in humans.

PURPOSE

This study investigated whether monosodium iodoacetate (MIA) injection into the IVD of rats could generate a reliable model of IVD degeneration.

STUDY DESIGN/SETTINGS

In vivo animal study.

METHODS

MIA was injected into two-disc spaces (L4-5 and L5-6) of Sprague-Dawley rats. Their behaviors were examined by measuring weight load shifts from hind to forefoot, rearing, and von Frey tests. We examined the inhibition of pain behavior through intraperitoneal morphine injection and measured cyclooxygenase-2 (COX-2) and transcription factor nuclear factor-kappa B (NF-κB) levels in the IVD and dorsal root ganglion (DRG) by Western blot. Bone alterations were assessed by microfocus computed tomography (micro-CT), and IVD and/or cartilage changes were evaluated by hematoxylin and eosin and safranin-O staining and inducible nitric oxide synthase (iNOS) immunohistochemistry. The other authors declare no conflicts of interest. This project funded by the Memorial Fund and the National Research Foundation of Korea (NRF).

RESULTS

We observed increased weight load shifts to the forefoot and decreased rearing. Morphine-injected rats showed reduced pain. NF-κB and COX-2 expression increased in the IVD and left and/or right DRG. Micro-CT analyses suggested progressive bone deformation. Histologic examination showed decreased IVD width and nucleus pulposus area. Cartilaginous changes indicated epiphyseal growth plate loss. Finally, iNOS expression was increased in the subchondral endplate.

CONCLUSIONS

These results suggest that low back pain (LBP) models can be developed by MIA injection into the IVDs of rats and that an animal model is useful for exploring degenerative alterations in the affected discs. Therefore, MIA injection may be a useful model for the study of changes in the IVD to elucidate the mechanisms underlying clinical symptoms, such as LBP, in patients with IVD degeneration.

CLINICAL SIGNIFICANCE

This model in which MIA was injected into the disc better represented the human histologic and behavioral characteristics than the existing puncture model.

Detecting pathological features and predicting fracture risk from dual-energy X-ray absorptiometry images using deep learning

Dual-energy X-ray absorptiometry (DXA) is the gold standard imaging method for diagnosing osteoporosis in clinical practice. The DXA images are commonly used to estimate a numerical value for bone mineral density (BMD), which decreases in osteoporosis. Low BMD is a known risk factor for osteoporotic fractures. In this study, we used deep learning to identify lumbar scoliosis and structural abnormalities that potentially affect BMD but are often neglected in lumbar spine DXA analysis. In addition, we tested the approach's ability to predict fractures using only DXA images. A dataset of 2949 images gathered by Kuopio Osteoporosis Risk Factor and Prevention Study was used to train a convolutional neural network (CNN) for classification. The model was able to classify scoliosis with an AUC of 0.96 and structural abnormalities causing unreliable BMD measurement with an AUC of 0.91. It predicted fractures occurring within 5 years from the lumbar spine DXA scan with an AUC of 0.63, meeting the predictive performance of combined BMD measurements from the lumbar spine and hip. In an independent test set of 574 clinical patients, AUC for lumbar scoliosis was 0.93 and AUC for unreliable BMD measurements was 0.94. In each classification task, neural network visualizations indicated the model's predictive strategy. We conclude that deep learning could complement the well established DXA method for osteoporosis diagnostics by analyzing incidental findings and image reliability, and improve its predictive ability in the future.

The Diagnostic Value of an X-ray-based Scoring System for Degeneration of the Cervical Spine: A Reproducibility and Validation Study

Background

In interventional pain medicine, cervical facet joint (CFJ) pain is commonly treated with CFJ denervation techniques, almost automatically assuming degeneration of the CFJs as an important cause of CFJ pain. A standard cervical X‐ray is still commonly used in the clinical evaluation of patients suspected for CFJ degeneration. Although degenerative features can be visualized by different radiological imaging techniques, the relation between radiological degenerative features of the cervical spine and pain remains controversial. Paramount in order to estimate the clinical usefulness of a radiological imaging is to establish the reproducibility of the radiological scoring system. A reproducible and clinically feasible diagnostic scoring system was developed to estimate cervical degeneration on standard cervical X‐rays.

Materials and Methods

A reproducibility study for the interpretation of degenerative abnormalities on standard cervical X‐rays was performed, using a dichotomous outcome (degenerative abnormalities present Yes/No). The estimation of intervertebral disc height loss on standard cervical X‐rays was validated with computed tomography (CT) scan measurements.

Results

Five radiological degenerative features on standard cervical X‐rays (disc height loss, anterior vertebral osteophytes, posterior vertebral osteophytes, vertebral end plate sclerosis, and uncovertebral osteoarthritis) showed a substantial to excellent reproducibility (kappa value ≥ 0.60). The qualitative definition of disc height loss used in the reproducibility study showed a substantial agreement with the actual measurements of disc height loss on CT scan (kappa value = 0.69).

Conclusion

Subjective judgment of a cervical standard X‐ray is a reproducible method to demonstrate degenerative abnormalities of the cervical spine.

Economic access influences degenerative spine disease outcomes at rural Late Medieval Villamagna (Lazio, IT)

OBJECTIVES

Degenerative joint disease in the spine is heavily influenced by genetic, environmental, and epigenetic factors, as well as exacerbated by physical activity and injury. The objective of this study was to investigate the multivariate relationship between known predictors of degenerative joint disease in the spine, such as age and sex, with mortuary indicators of economic access such as grave inclusions, burial location, and burial type.

MATERIALS AND METHODS

The presence and severity of vertebral osteophytosis (VO) and vertebral osteoarthritis (VOA) was recorded for the vertebral columns of N = 106 adult individuals from the Late Medieval period at the rural monastery of San Pietro at Villamagna in Lazio, Italy (1300-1450 AD). Multiple skeletal indicators of degenerative joint disease, morphological sex, and age were compared with differences in mortuary treatment across four regions of the spine.

RESULTS

There are marked differences in severe joint disease outcome between groups with more and less economic access. Relative risk ratios suggest that males and females with less economic access have elevated risk for VO and VOA in specific spine regions, although this effect is reduced among females.

DISCUSSION

Current research on the consequences of economic and social inequality point to the important role of economic inequality in shaping disease outcomes. Our results suggest that biocultural effects of reduced economic access at the intraclass level may increase vulnerability to the downstream effects of risk exposure (e.g., biomechanical injure, physical activity, biochemical imbalance), and ultimately increase the risk and prevalence for severe degenerative disease outcomes in medieval Italy.

Preparation and in vitro evaluation of PLA/biphasic calcium phosphate filaments used for fused deposition modelling of scaffolds

Ceramic materials such as calcium phosphates (CaPs) with a composition similar to the mineral phase of bones and polymeric polylactic acid (PLA) are potential candidates for the manufacturing of scaffolds to act as bone substitutes and for tissue engineering applications, due to their bioresorbability and biocompatibility. Variables such as porosity, topography, morphology, and mechanical properties play an essential role in the scaffolds response. In this paper, a polymer/ceramic composite filament of 1.7 mm in diameter based on PLA and biphasic calcium phosphates (BCPs) was obtained by hot-melt extrusion in a single screw extruder. The particles of BCP were obtained by solution-combustion synthesis, and the PLA used was commercial grade. The BCPs ceramics were characterized by X-ray diffraction (XRD), scanning electron microscopic (SEM), transmission electron microscopy (TEM), and Brunauer, Emmett, and Teller (BET). It was possible to confirm that the main inorganic phases were hydroxyapatite (HAP) and tricalcium phosphate (TCP) with grain sizes below 100 nm and with high porosity. The Filaments obtained are a bit fragile but were able to be used in fused deposition modelling (FDM) using low-cost commercial printers. The filaments were characterized by SEM and energy dispersive X-ray (EDX). The in-vitro tests of filaments showed deposition of apatite phases on their surface, non-cytotoxic behavior, adequate cell proliferation and cell adhesion.

Growing a backbone - functional biomaterials and structures for intervertebral disc (IVD) repair and regeneration: challenges, innovations, and future directions

Back pain and associated maladies can account for an immense amount of healthcare cost and loss of productivity in the workplace. In particular, spine related injuries in the US affect upwards of 5.7 million people each year. The degenerative disc disease treatment almost always arises due to a clinical presentation of pain and/or discomfort. Preferred conservative treatment modalities include the use of non-steroidal anti-inflammatory medications, physical therapy, massage, acupuncture, chiropractic work, and dietary supplements like glucosamine and chondroitin. Artificial disc replacement, also known as total disc replacement, is a treatment alternative to spinal fusion. The goal of artificial disc prostheses is to replicate the normal biomechanics of the spine segment, thereby preventing further damage to neighboring sections. Artificial functional disc replacement through permanent metal and polymer-based components continues to evolve, but is far from recapitulating native disc structure and function, and suffers from the risk of unsuccessful tissue integration and device failure. Tissue engineering and regenerative medicine strategies combine novel material structures, bioactive factors and stem cells alone or in combination to repair and regenerate the IVD. These efforts are at very early stages and a more in-depth understanding of IVD metabolism and cellular environment will also lead to a clearer understanding of the native environment which the tissue engineering scaffold should mimic. The current review focusses on the strategies for a successful regenerative scaffold for IVD regeneration and the need for defining new materials, environments, and factors that are so finely tuned in the healthy human intervertebral disc in hopes of treating such a prevalent degenerative process.

Posture during the use of electronic devices in people with chronic neck pain: A 3D motion analysis project

BACKGROUND

Non-neutral postures during computerised device use coupled with increased usage may increase the risk of neck pain. Greater knowledge of postures that individuals with neck pain adopt during computerised device use is warranted.

OBJECTIVE

To evaluate neck and upper limb posture while using a tablet, laptop and desktop computer (sitting and standing) in individuals with chronic neck pain.

METHODS

Differences in three-dimensional kinematic variables were assessed during four conditions: tablet, laptop, desktop computer (sitting and standing) in 22 individuals with chronic neck pain >3 months. Differences between kinematic variables were determined using one-way repeated measures ANOVA with Bonferroni post-hoc tests.

RESULTS

Compared to the desktop (sitting), tablet and laptop use resulted in increased neck flexion (mean difference tablet - 14.42°, 95% CI - 19.88, -8.96, P < 0.001; laptop -7.19°, -12.08, -2.31, P = .020); upper trunk flexion (tablet -14.89°, -20.22, -9.56, P < 0.001; laptop -5.56°, -10.02, -1.09, P = .009) and tablet bilateral shoulder elevation (left 11.01 mm, 2.01, 20.04, P < .016; right 13.08 mm, 3.09, 23.11, P < .006).

CONCLUSIONS

Tablet and laptop use resulted in greater neck flexion, bilateral shoulder elevation and upper trunk flexion compared to a standard desktop computer, suggesting individuals with chronic neck pain should be mindful of their posture when using these smaller devices. Future research should explore how differences in posture may influence neck pain.

Clinical Presentations of Lumbar Disc Degeneration and Lumbosacral Nerve Lesions

Lumbar disc degeneration is defined as the wear and tear of lumbar intervertebral disc, and it is mainly occurring at L3-L4 and L4-S1 vertebrae. Lumbar disc degeneration may lead to disc bulging, osteophytes, loss of disc space, and compression and irritation of the adjacent nerve root. Clinical presentations associated with lumbar disc degeneration and lumbosacral nerve lesion are discogenic pain, radical pain, muscular weakness, and cutaneous. Discogenic pain is usually felt in the lumbar region, or sometimes, it may feel in the buttocks, down to the upper thighs, and it is typically presented with sudden forced flexion and/or rotational moment. Radical pain, muscular weakness, and sensory defects associated with lumbosacral nerve lesions are distributed on lower extremities, the buttock, lower abdomen, and groin region. A lumbosacral plexus lesion presents different symptoms in the territories of the lumbar and sacral nerves. Patients with lumbar plexus lesion clinically present with weakness of hip flexion, knee extension, thigh adduction, and sensory loss in the lower abdomen, inguinal region, and over the entire medial, lateral, and anterior surfaces of the thigh and the medial lower leg, while sacral plexus lesion presents clinical symptoms at nerve fibers destined for the sciatic nerve, common peroneal nerve, and pudendal nerve. Weakness of ankle inversion, plantar flexion, and foot drop are the main clinical manifestations of the sacral plexus lesion area. Numbness and decreased sensation are also present along the anterolateral calf and dorsum of the foot. On examination, foot eversion is usually stronger than foot dorsiflexion. The patients may also present with pain and difficulty of bowel movements, sexual dysfunction assessments, and loss of cutaneous sensation in the areas of the anal canal, anus, labia major, labia minor, clitoris, penis, and scrotum.

Long-term clinical and magnetic resonance imaging follow-up of dogs with osseous-associated cervical spondylomyelopathy

BACKGROUND

Osseous-associated cervical spondylomyelopathy (OA-CSM) is a complex disorder with limited long-term survival. The longitudinal progression is currently unknown.

OBJECTIVE

To describe changes on magnetic resonance imaging (MRI) over a 2-year minimum period. We hypothesized that spinal lesions would progress in the majority of dogs.

ANIMALS

Eleven dogs previously diagnosed with OA-CSM were prospectively studied. Nine dogs were treated medically, whereas 2 were treated surgically.

METHODS

Clinical and MRI follow-up were performed with a median time between MRI studies of 30 months (range, 24-54). Morphologic assessment evaluated vertebral canal stenosis, spinal cord compression, foraminal stenosis, and articular processes, among other variables. Morphometric assessment included vertebral canal area, spinal cord area, area of the articular processes, and foraminal height.

RESULTS

On follow-up MRI, the most affected site at the initial examination in medically treated dogs had progressed in 4 of 9 dogs, improved in 4, and was unchanged in 3. Clinically, all dogs except 2 medically treated dogs were unchanged to improve at follow-up. Initially, 50 of 60 (83.3%) intervertebral spaces had vertebral canal stenosis, whereas in the follow-up MRI 82.3% did. Of the sites with stenosis, 45.7% were unchanged, 18.6% improved, and 38.9% worsened. Morphometry identified significant decreases in vertebral canal and spinal cord areas at C4-C5 through C6-C7, and significant progression of articular process irregularities at C3-C4 and C6-C7.

CONCLUSIONS AND CLINICAL IMPORTANCE

This long-term follow-up study of dogs with OA-CSM did not identify clinical or MRI progression of lesions in the majority of dogs.

Inertial Sensors as a Tool for Diagnosing Discopathy Lumbosacral Pathologic Gait: A Preliminary Research

Background: the goal of the study is to ascertain the influence of discopathy in the lumbosacral (L-S) segment on the gait parameters. The inertial sensors are used to determine the pathologic parameters of gait. Methods: the study involved four patients (44, 46, 42, and 38 years). First, the goal of the survey was to analyze by a noninvasive medical test magnetic resonance imaging (MRI) of each patient. Next, by using inertial sensors, the flexion-extension of joint angles of the left and right knees were calculated. The statistical analysis was performed. The wavelet transform was applied to analyze periodic information in the acceleration data. Results: in the patients with discopathy, the amount of knee flexion attained during stance phase is significantly lower than that of normal (health side), which could indicate poor eccentric control or a pain avoidance mechanism. The biggest differences are observed in the Initial Swing phase. Bending of the lower limb in the knee joint at this stage reaches maximum values during the entire gait cycle. Conclusions: It has been difficult to quantify the knee angle during gait by visual inspection. The inertial measurement unit (IMU) system can be useful in determining the level of spine damage and its degree. In patients in the first stages of the intervertebral disc disease who may undergo conservative treatment, it may also partially delay or completely exclude the decision to perform a complicated imaging examination which is MRI, often showing a false positive result in this phase of the disease.

Cervical Discs as a Source of Neck Pain. An Analysis of the Evidence

OBJECTIVESBACKGROUND

Objectives To determine the extent and strength of evidence that supports the belief that cervical intervertebral discs are a source of neck pain.

DESIGN

Design The evidence from anatomical, laboratory, experimental, diagnostic, and treatment studies was summarized and analyzed for concept validity, face validity, content validity, and construct validity.

RESULTS

Results Evidence from basic sciences shows that cervical discs have a nociceptive innervation, and experimental studies show that they are capable of producing neck pain. Disc stimulation has been developed as a diagnostic test but has rarely been used in a disciplined fashion. The prevalence of cervical disc pain has not been properly established but appears to be low. No treatment has been established that reliably achieves complete relief of neck pain in substantial proportions of patients.

CONCLUSIONS

Conclusions Basic science evidence supports the concept of cervical disc pain, but epidemiologic and clinical evidence to vindicate the clinical application of the concept is poor or lacking.

Low Back Pain, a Comprehensive Review: Pathophysiology, Diagnosis, and Treatment

PURPOSE OF REVIEW

Low back pain encompasses three distinct sources: axial lumbosacral, radicular, and referred pain. Annually, the prevalence of low back pain in the general US adult population is 10-30%, and the lifetime prevalence of US adults is as high as 65-80%.

RECENT FINDINGS

Patient history, physical exam, and diagnostic testing are important components to accurate diagnosis and identification of patient pathophysiology. Etiologies of low back pain include myofascial pain, facet joint pain, sacroiliac joint pain, discogenic pain, spinal stenosis, and failed back surgery. In chronic back pain patients, a multidisciplinary, logical approach to treatment is most effective and can include multimodal medical, psychological, physical, and interventional approaches. Low back pain is a difficult condition to effectively treat and continues to affect millions of Americans every year. In the current investigation, we present a comprehensive review of low back pain and discuss associated pathophysiology, diagnosis, and treatment.

Genetic predictors of recovery in low back and lumbar radicular pain

Previous data suggest that persistent back pain may be associated with genetic variability. In this study, we assessed the correlation between 8 genetic polymorphisms (VDR, COL11, MMP1, MMP9, IL-1α, IL-1RN, OPRM1, COMT) and pain recovery in patients with low back pain (LBP) and lumbar radicular pain (LRP). In total, 296 patients with LBP or LRP were followed for 5 years. The patients underwent standardized clinical examination and completed pain and function questionnaires. Univariate linear regression associations with P values <0.1 were included in the multivariable analysis, adjusting for pain intensity at baseline, age, sex, smoking, body mass index, and LBP or LRP. Pain intensity at 5-year follow-up was associated with VDR rs731236 (B = -0.5, 95% confidence interval [CI] -0.9 to -0.1, P = 0.017), MMP9 rs17576 (B = 0.5, 95% CI 0.1-0.9, P = 0.022), and OPRM1 rs1799971 (B = -0.8, 95% CI -1.4 to -0.2, P = 0.006) in the univariate analyses. MMP9 rs17576 and OPRM1 rs1799971 remained significant (B = 0.4, 95% CI 0.05-0.8, P = 0.026 and B = -0.8, 95% CI -1.3 to -0.2, P = 0.007) in the multivariable model. Thus, the data demonstrated that the rare allele of MMP9 rs17576 was associated with poor pain recovery, whereas the rare allele of OPRM1 rs1799971 was associated with better pain recovery at 5-year follow-up in the LBP and LRP patients. In particular, the present study suggested that the OPRM1 rs179971 A>G in men was associated with better long-term pain recovery. In men, the OPRM1 rs1799971 explained 4.7% of the variance of pain intensity. We conclude that the MMP9 rs17576 and OPRM1 rs1799971 genotypes may affect 5-year recovery in patients with LBP and LRP.

ABCs of the degenerative spine

Degenerative changes in the spine have high medical and socioeconomic significance. Imaging of the degenerative spine is a frequent challenge in radiology. The pathogenesis of this degenerative process represents a biomechanically related continuum of alterations, which can be identified with different imaging modalities. The aim of this article is to review radiological findings involving the intervertebral discs, end plates, bone marrow changes, facet joints and the spinal canal in relation to the pathogenesis of degenerative changes in the spine. Findings are described in association with the clinical symptoms they may cause, with a brief review of the possible treatment options. The article provides an illustrated review on the topic for radiology residents.

TEACHING POINTS

• The adjacent vertebrae, intervertebral disc, ligaments and facet joints constitute a spinal unit. • Degenerative change is a response to insults, such as mechanical or metabolic injury. • Spine degeneration is a biomechanically related continuum of alterations evolving over time.

Level of Education as a Risk Factor for Extensive Prevalence of Cervical Intervertebral Disc Degenerative Changes and Chronic Neck Pain

OBJECTIVE

The aim of this study was to document the prevalence of degenerative intervertebral disc changes in the patients who previously reported symptoms of neck pain and to determine the influence of education level on degenerative intervertebral disc changes and subsequent chronic neck pain.

METHODS

One hundred and twelve patients were randomly selected from the University Hospital in Mostar, Bosna and Herzegovina, (aged 48.5±12.7 years) and submitted to magnetic resonance imaging (MRI) of the cervical spine. MRI of 3.0 T (Siemens, Skyrim, Erlangen, Germany) was used to obtain cervical spine images. Patients were separated into two groups based on their education level: low education level (LLE) and high education level (HLE). Pfirrmann classification was used to document intervertebral disc degeneration, while self-reported chronic neck pain was evaluated using the previously validated Oswestry questionnaire.

RESULTS

The entire logistic regression model containing all predictors was statistically significant, (χ²(3)=12.2, p=0.02), and was able to distinguish between respondents who had chronic neck pain and vice versa. The model explained between 10.0% (Cox-Snell R²) and 13.8% (Nagelkerke R²) of common variance with Pfirrmann classification, and it had the strength to discriminate and correctly classify 69.6% of patients. The probability of a patient being classified in the high or low group of degenerative disc changes according to the Pfirrmann scale was associated with the education level (Wald test: 5.5, p=0.02). Based on the Pfirrmann assessment scale, the HLE group was significantly different from the LLE group in the degree of degenerative changes of the cervical intervertebral discs (U=1,077.5, p=0.001).

CONCLUSION

A moderate level of intervertebral disc degenerative changes (grade II and III) was equally matched among all patients, while the overall results suggest a higher level of education as a risk factor leading to cervical disc degenerative changes, regardless of age differences among respondents.

Genes associated with persistent lumbar radicular pain; a systematic review

Background

The aim of the present study was to provide an overview of the literature addressing the role of genetic factors and biomarkers predicting pain recovery in newly diagnosed lumbar radicular pain (LRP) patients.

Methods

The search was performed in Medline OVID, Embase, PsycInfo and Web of Science (2004 to 2015). Only prospective studies of patients with LRP addressing the role of genetic factors (genetic susceptibility) and pain biomarkers (proteins in serum) were included. Two independent reviewers extracted the data and assessed methodological quality.

Results

The search identified 880 citations of which 15 fulfilled the inclusion criteria. Five genetic variants; i.e., OPRM1 rs1799971 G allele, COMT rs4680 G allele, MMP1 rs1799750 2G allele, IL1α rs1800587 T allele, IL1RN rs2234677 A allele, were associated with reduced recovery of LRP. Three biomarkers; i.e., TNFα, IL6 and IFNα, were associated with persistent LRP.

Conclusion

The present results indicate that several genetic factors and biomarkers may predict slow recovery in LRP. Still, there is a need for replication of the findings. A stricter use of nomenclature is also highly necessary.

Trial registration

The review is registered PROSPERO 20^th of November 2015. Registration number is CRD42015029125.

Cervical Facet Joint Imaging-Guided Injections: A Comparison of Outcomes in Patients Referred Based on Imaging Findings Vs Palpation for Pain

OBJECTIVES

The purpose of this study was to compare outcomes of patients referred for cervical facet joint injections by either a medical doctor (MD) primarily basing the selection of facet levels on structural changes found on imaging vs a doctor of chiropractic (DC) selecting the levels for injection based on palpation for pain.

METHODS

This was a prospective cohort outcome study including 121 consecutive patients receiving cervical facet injections with completed outcomes questionnaires. Medical doctors referred 91 patients and DCs referred 30 patients. Baseline pain numerical rating scale (NRS) data were collected. Outcomes collected at 1 day, 1 week, and 1 month after injection included NRS pain levels and overall "improvement" using the Patient Global Impression of Change scale (primary outcome). The responses "much better" and "better" were considered "improved." The proportion improved was compared between the 2 groups using the χ(2) test. NRS change scores for the 2 groups were compared using the unpaired t test.

RESULTS

At 1 day, "improvement" was reported in 44.8% of DC-and 29.7% of MD-referred patients (P = .17). At 1 week, 37.9% of DC-and 21.3% of MD-referred patients reported improvement (P = .03). At 1 month, 50.0% of DC-and 31.0% of MD-referred patients reported improvement (P = .1).

CONCLUSIONS

A greater proportion of DC-referred patients (injection level based on palpation for pain) reported "improvement" at all follow-up time points. This finding reached statistical significance at 1 week. These findings may be because DCs use palpation for pain to determine injection level whereas MDs rely more on imaging findings. The results suggest that the reported moderate results of facet injections partially may be due to the inaccurate selection of the spinal level treated.

Comparison of facet joint activity on 99mTc-MDP SPECT/CT with facet joint signal change on MRI with fat suppression

PURPOSE

We compared signal change on magnetic resonance imaging (MRI) with fat suppression and bone scan activity of lumbar facet joints to determine if these two imaging findings are correlated.

METHODS

We retrospectively identified all patients who underwent imaging of the lumbar spine for pain evaluation using both technetium-99m methylene disphosphonate single-photon emission computed tomography/computed tomography (99mTc-MDP SPECT/CT) and MRI with at least one fat-suppressed T2- or T1-weighted sequence with gadolinium enhancement within a 180-day interval, at our institution between 1 January 2008 and 19 February 2013. Facet joint activity on 99mTc-MDP SPECT/CT and peri-facet signal change on MRI were rated as normal or increased. Agreement between the two examination types were determined with the κ and prevalence-adjusted bias-adjusted κ (PABAK) statistics.

RESULTS

This study included 60 patients (28 male, 47%), with a mean age of 49±19.7 years (range, 12-93 years). The κ value indicated no agreement between 99mTc-MDP SPECT/CT and MRI (κ=-0.026; 95% confidence interval: -0.051, 0.000). The PABAK values were fair to high at each spinal level, which suggests that relatively low disease prevalence lowered the κ values. Together, the κ and PABAK values indicate that there is some degree of intermodality agreement, but that it is not consistent.

CONCLUSION

Overall, facet joint signal change on fat-suppressed MRI did not always correlate with increased 99mTc-MDP SPECT/CT activity. MRI and 99mTc-MDP SPECT/CT for facet joint evaluation should not be considered interchangeable examinations in clinical practice or research.

The degenerative cervical spine

Imaging techniques provide excellent anatomical images of the cervical spine. The choice to use one technique or another will depend on the clinical scenario and on the treatment options. Plain-film X-rays continue to be fundamental, because they make it possible to evaluate the alignment and bone changes; they are also useful for follow-up after treatment. The better contrast resolution provided by magnetic resonance imaging makes it possible to evaluate the soft tissues, including the intervertebral discs, ligaments, bone marrow, and spinal cord. The role of computed tomography in the study of degenerative disease has changed in recent years owing to its great spatial resolution and its capacity to depict osseous components. In this article, we will review the anatomy and biomechanical characteristics of the cervical spine, and then we provide a more detailed discussion of the degenerative diseases that can affect the cervical spine and their clinical management.

Signal intensity loss of the intervertebral discs in the cervical spine of young patients on fluid sensitive sequences

OBJECTIVE

To evaluate the signal intensity (SI) of the intervertebral discs of the cervical spine on magnetic resonance (MR) fluid sensitive sequences, and correlate this to secondary signs of degeneration on MR and radiographs as well as to age.

MATERIAL AND METHODS

A total of 265 patients aged ≥16 with back pain (≥3-months, <2-year, onset <45-years) from the SPondyloArthritis Caught Early (SPACE) cohort were included. Sagittal 1.5 T MR images and lateral radiographs of the cervical spine were independently evaluated by two readers for: SI of the intervertebral discs using a grading system based of Pfirrmann (grade 1 normal/bright SI; 2 inhomogeneous/bright SI; 3 inhomogeneous/mildly decreased SI; 4 inhomogeneous/markedly decreased SI; 5 signal void), disc herniation and Modic changes (MRI) and disc space narrowing, osteophytes and sclerosis (radiograph). Readers were blinded for clinical information. Descriptive statistics were used for characteristics and prevalence of findings, and regression analysis was used for age and grades.

RESULTS

Of 265 patients (36% male, mean age 30), 221 (83%) patients had 1 to 6 discs (median 4) with decreased SI. Of 1,590 discs, 737 (46%) were grade 1; 711 (45%) grade 2; 133 (8%) grade 3; 8 (1%) grade 4 and 1 (0%) grade 5. Secondary signs of degeneration were rare and seen predominantly in C5-C7 and appear to be related to signal loss grade 3 and 4.

CONCLUSION

Low signal intensity of intervertebral discs in absence of secondary degenerative signs in the cervical spine on fluid sensitive MR images might be pre-existing and part of the natural course.

Zygapophysial joint pain in selected patients

The zygapophysial joints (z-joints), together with the intervertebral disc, form a functional spine unit. The joints are typical synovial joints with an innervation from two medial branches of the dorsal rami. The joint capsule and the surrounding structures have an extensive nerve supply. The stretching of the capsule and loads being transmitted through the joint can cause pain. The importance of the z-joints as a pain generator is often underestimated because the prevalence of z-joint pain (10%-80%) is difficult to specify. Z-joint pain is a somatic referred pain. Morning stiffness and pain when moving from a sitting to a standing position are typical. No historic or physical examination variables exist to identify z-joint pain. Also, radiologic findings do not have a diagnostic value for pain from z-joints. The method with the best acceptance for diagnosing z-joint pain is controlled medial branch blocks (MBBs). They are the most validated of all spinal interventions, although false-positive and false-negative results exist and the degree of pain relief after MBBs remains contentious. The prevalence of z-joint pain increases with age, and it often comes along with other pain sources. Degenerative changes are commonly found. Z-joints are often affected by osteoarthritis and inflammatory processes. Often additional factors including synovial cysts, spondylolisthesis, spinal canal stenosis, and injuries are present. The only truly validated treatment is medial branch neurotomy. The available technique vindicates the use of radiofrequency neurotomy provided that the correct technique is used and patients are selected rigorously using controlled blocks.

Efficacy of intervertebral disc regeneration with stem cells - a systematic review and meta-analysis of animal controlled trials

Management of intervertebral disc (IVD) degenerative disease is challenging, as it is accompanied by irreversible loss of IVD cells. Stem cell transplantation to the disc has shown promise in decelerating or arresting the degenerative process. Multiple pre-clinical animal trials have been conducted, but with conflicting outcomes. To assess the effect of stem cell transplantation, a systematic review and meta-analysis was performed. A comprehensive literature search was conducted through Week 3, 2015. Inclusion criteria consisted of controlled animal trials. Two reviewers screened abstracts and full texts. Disagreements were resolved by a third reviewer. Random effects models were constructed to pool standardized mean difference (SMD). Twenty two studies were included; nine of which were randomized. Statistically significant differences were found with the stem cell group exhibiting increased disc height index (SMD=3.64, 95% confidence interval (CI): 2.49, 4.78; p<0.001), increased MRI T2 signal intensity (SMD=2.28, 95% CI: 1.48, 3.08; p<0.001), increased Type II collagen mRNA expression (SMD=3.68, 95% CI: 1.66, 5.70; p<0.001), and decreased histologic disc degeneration grade (SMD=-2.97, 95% CI: -3.97, -1.97; p<0.001). There was statistical heterogeneity between studies that could not be explained with pre-planned subgroup analyses based on animal species, study designs, and transplanted cell types. Stem cells transplanted to the IVD in quadruped animals decelerate or arrest the IVD degenerative process. Further studies in human clinical trials will be needed to understand if such benefit can be translated to bipedal humans.

Low-back pain

Low-back pain is one of the most common painful conditions experienced by humans throughout their life. Some occupational risk factors (namely, heavy manual material handling) may also contribute to the development of low-back pain: due to the high prevalence of both low-back pain and manual material handling in the adult working population, it has been estimated that low-back pain is probably the most common occupational disorder worldwide. Lifetime prevalence of low-back pain has been reported to be as high as 84%, depending on the case definition used, and no age group is spared, even children. Although low-back pain is not a lethal condition, it was estimated at the third rank among all diseases by disability-adjusted life-years in 2010 in the USA, after ischemic heart disease and chronic obstructive pulmonary disease, and at the first rank by years lived with disability. It also ranked high (13th) globally for the same year, in disability-adjusted life-years. Low-back pain is currently classified as nonspecific/specific as to putative cause and as acute (lasting less than 6 weeks), subacute (6-12 weeks), or chronic (more than 12 weeks) according to duration of symptoms. The distinction between nonspecific/specific and acute/subacute/chronic low-back pain is useful not only for epidemiologic studies, but also (mainly) for choosing the appropriate strategy for the diagnosis and treatment of the disorder. Workplace risk factors for low-back pain include manual lifting and whole-body vibration exposure. This chapter will provide an overview of modern concepts of low-back pain (in general) and will then outline some distinctive features of work-related low-back pain.

Cervical vertebral trabecular bone mineral density in Great Danes with and without osseous-associated cervical spondylomyelopathy

Background

Great Danes (GDs) with osseous‐associated cervical spondylomyelopathy (CSM) have osteoarthritis (OA) of the cervical vertebrae. OA is often associated with increases in bone mineral density (BMD) in people and dogs.

Hypothesis/Objectives

To compare the trabecular BMD of the cervical vertebrae between clinically normal (control) GDs and GDs with osseous‐associated CSM by using computed tomography (CT). We hypothesized that the vertebral trabecular BMD of CSM‐affected GDs would be higher than that of control GDs.

Animals

Client‐owned GDs: 12 controls, 10 CSM affected.

Methods

Prospective study. CT of the cervical vertebral column was obtained alongside a calibration phantom. By placing a circular region of interest at the articular process joints, vertebral body, pedicles, and within each rod of the calibration phantom, trabecular BMD was measured in Hounsfield units, which were converted to diphosphate equivalent densities. Trabecular BMD measurements were compared between CSM‐affected and control dogs, and between males and females within the control group.

Results

Differences between CSM‐affected and control dogs were not significant for the articular processes (mean = −39; P = .37; 95% CI: −102 to 24), vertebral bodies (mean = −62; P = .08; 95% CI: −129 to 6), or pedicles (mean = −36; P = .51; 95% CI: −105 to 33). Differences between female and male were not significant.

Conclusions and Clinical Importance

This study revealed no difference in BMD between control and CSM‐affected GDs. Based on our findings no association was detected between cervical OA and BMD in GDs with CSM.

Head and cervical spine posture in behaving rats: implications for modeling human conditions involving the head and cervical spine

The aim of this study was to define the temporal and spatial (postural) characteristics of the head and cervical vertebral column (spine) of behaving rats in order to better understand their suitability as a model to study human conditions involving the head and neck. Time spent in each of four behavioral postures was determined from video tape recordings of rats (n = 10) in the absence and presence of an intruder rat. Plain film radiographic examination of a subset of these rats (n = 5) in each of these postures allowed measurement of head and cervical vertebral column positions adopted by the rats. When single they were quadruped or crouched most (∼80%) of the time and bipedal either supported or free standing for only ∼10% of the time. The introduction of an intruder significantly (P < 0.0001) reduced the proportion of time rats spent quadruped (median, from 71% to 47%) and bipedal free standing (median, from 2.9% to 0.4%). The cervical spine was orientated (median, 25-75 percentile) near vertical (18.8°, 4.2°-30.9°) when quadruped, crouched (15.4°, 7.6°-69.3°) and bipedal supported (10.5°, 4.8°-22.6°) but tended to be less vertical oriented when bipedal free standing (25.9°, 7.7°-39.3°). The range of head positions relative to the cervical spine was largest when crouched (73.4°) and smallest when erect free standing (17.7°). This study indicates that, like humans, rats have near vertical orientated cervical vertebral columns but, in contrast to humans, they displace their head in space by movements at both the cervico-thoracic junction and the cranio-cervical regions.

Diagnostic and therapeutic spinal interventions: Diskography

Diskography (provocation diskography, disk stimulation) is an invasive diagnostic test performed to confirm or exclude internal disk disruption as the cause of axial spine pain. Diskography involves injecting fluid into the nucleus of the disk under manometric control; a positive response is reproduction of typical pain. Extensive but indirect literature validates diskography in the lumbar spine; it is less well-supported in the cervical or thoracic spine. Risks include rare instances of infection and neural injury; lumbar diskography may be associated with accelerated disk degeneration. Diskography has utility in establishing a diagnosis of diskogenic pain. When negative, it prevents inappropriate interventions directed at the disk; when positive, it prevents interventions directed at other axial pain generators. Its role in selecting patients for therapies directed at diskogenic pain is limited by the lack of available validated treatments.

Diagnostic and therapeutic spinal interventions: Facet joint interventions

Axial spine pain is a common condition that is due to facet joint disease in some patients. Local anesthetic blocks of the medial branches of the dorsal rami of the spinal nerves that innervate facet joints are used to identify painful facet joints. Subsequent radiofrequency neurotomy of the medial branches serving symptomatic facet joints may provide prolonged albeit impermanent pain relief. The diagnostic blocks and radiofrequency treatments are best validated in the cervical spine. Neurologists should be aware that patients with axial spine pain who are referred to a pain clinic or pain management facility are likely to be considered for diagnostic and therapeutic interventions directed at facet joints and their sensory nerve supply.

Cervical spondylomyelopathy in Great Danes: a magnetic resonance imaging morphometric study

Morphometric investigations comparing normal and affected animals increase our understanding of spinal diseases in dogs. The aim of this study was to generate morphometric data for osseous-associated cervical spondylomyelopathy (CSM) in Great Danes (GDs). Magnetic resonance imaging (MRI) morphometric features of the cervical vertebral column of GDs with and without clinical signs of CSM were characterized and compared. Thirty client-owned GDs were prospectively enrolled, including 15 clinically normal and 15 CSM-affected GDs. All dogs underwent MRI of the cervical to thoracic vertebral column (C2-C3 through T1-T2). Areas of the cranial and caudal articular processes, and the height, width and areas of the vertebral canal and spinal cord were determined. Middle foraminal heights were measured. Intervertebral disc width was measured before and after traction. Intraobserver and interobserver agreement were calculated. CSM-affected GDs had larger areas of the caudal articular processes from C2-C3 through T1-T2. In CSM-affected GDs, the vertebral canal and spinal cord areas were significantly smaller at C5-C6 and C6-C7, the vertebral canal width was significantly narrower at C6-C7 and C7-T1, and the spinal cord width was significantly narrower at C5-C6 and C6-C7. Middle foraminal height was smaller in CSM-affected GDs from C3-C4 through C7-T1. Neutral intervertebral disc widths were smaller in CSM-affected GDs. It was concluded that the cervical vertebral canal dimensions are significantly different between normal and CSM-affected GDs. Absolute vertebral canal stenosis and severe foraminal stenosis involving the cervical vertebrae distinguish CSM-affected from clinically normal GDs. These findings are relevant to the pathogenesis of osseous-associated CSM and should be taken into consideration when performing imaging studies and planning surgery.

Frequency of discordance between facet joint activity on technetium Tc99m methylene diphosphonate SPECT/CT and selection for percutaneous treatment at a large multispecialty institution

BACKGROUND AND PURPOSE

The clinical impact of facet joint bone scan activity is not fully understood. The hypothesis of this study is that facet joints targeted for percutaneous treatment in clinical practice differ from those with reported activity on technetium Tc99m methylene diphosphonate SPECT/CT.

MATERIALS AND METHODS

All patients with a technetium Tc99m methylene diphosphonate SPECT/CT scan of the lumbar or cervical spine who underwent subsequent percutaneous facet joint steroid injection or comparative medial branch blocks at our institution between January 1, 2008, and February 19, 2013, were identified. Facet joints with increased activity were compared with those treated. A chart review characterized the clinical reasons for treatment discrepancies.

RESULTS

Of 74 patients meeting inclusion criteria, 52 (70%) had discrepant imaging findings and treatment selection of at least 1 facet joint, whereas 34 patients (46%) had a side (right vs left) discrepancy. Only 92 (70%) of 132 facet joints with increased activity were treated, whereas 103 (53%) of 195 of treated facet joints did not have increased activity. The most commonly documented clinical rationale for discrepancy was facet joint activity that was not thought to correlate with clinical findings, cited in 18 (35%) of 52 patients.

CONCLUSIONS

Facet joints undergoing targeted percutaneous treatment were frequently discordant with those demonstrating increased technetium Tc99m methylene diphosphonate activity identified by SPECT/CT at our institution, in many cases because the active facet joint(s) did not correlate with clinical findings. Further prospective double-blinded investigations of the clinical significance of facet joint activity by use of technetium Tc99m methylene diphosphonate SPECT/CT and comparative medial branch blocks are needed.