Diagnostic Modality in Spine Disease: A Review

Article information

Asian Spine J. 2020;14(6):910-920
Publication date (electronic) : 2020 December 22
doi : https://doi.org/10.31616/asj.2020.0593
1Department of Orthopaedic Surgery, Hanil General Hospital, Seoul, Korea
2Department of Physical Medicine and Rehabilitation, Yeungnam University College of Medicine, Daegu, Korea
3Department of Rehabilitation, Dankook University College of Medicine, Cheonan, Korea
4Department of Orthopaedic Surgery, Yeungnam University Medical Center, Yeungnam University College of Medicine, Daegu, Korea
Corresponding author: Gun Woo Lee Department of Orthopaedic Surgery, Yeungnam University Medical Center, Yeungnam University College of Medicine, 170 Hyeonchungro, Nam-gu, Daegu 42415, Korea Tel: +82-53-620-3642, Fax: +82-53-628-4020, E-mail: gwlee1871@ynu.ac.kr
Received 2020 November 19; Revised 2020 November 26; Accepted 2020 November 26.

Abstract

Spine diseases are common and exhibit several causes, including degeneration, trauma, congenital issues, and other specific factors. Most people experience a variety of symptoms of spine diseases during their lifetime that are occasionally managed with conservative or surgical treatments. Accurate diagnosis of the spine pathology is essential for the appropriate management of spine disease, and various imaging modalities can be used for the diagnosis, including radiography, computed tomography (CT), magnetic resonance imaging (MRI), and other studies such as EOS, bone scan, single photon emission CT/CT, and electrophysiologic test. Patient (or case)-specific selection of the diagnostic modality is crucial; thus, we should be aware of basic information and approaches of the diagnostic modalities. In this review, we discuss in detail, about diagnostic modalities (radiography, CT, MRI, electrophysiologic study, and others) that are widely used for spine disease.

Introduction

With advances in technology, various imaging modalities have been developed for diagnosing spine pathologies. Radiography, the first-line imaging modality, is based on X-rays and allows the visualization of the bony structure of the spine, estimation of the state of the spinal canal, and identification of specific pathologies, such as ossification of the posterior longitudinal ligament (OPLL) and osteoarthritis. However, the spinal cord and nerve roots cannot be detailed; therefore, radiography has not been recognized as the gold standard for the diagnostic workup of the spine. Computed tomography (CT) and magnetic resonance imaging (MRI) are the second-line imaging modalities for achieving a better understanding of the pathologies of the spine and establish the direction for management. CT is a valuable imaging modality for both, confirmation of diagnosis and elimination of differential diagnosis. CT is fast, non-invasive, and highly accurate; however, it involves certain drawbacks. CT cannot properly detect certain spinal cord lesions, disk pathologies, and minor lesions. Owing to the previously mentioned limitations of radiography and CT, MRI has been considered the gold standard diagnostic modality for spinal pathologies. Additionally, most spine-related diseases impact the neural structures, including the spinal cord and nerve roots, resulting in several neurological symptoms such as radiating pain, numbness, or paralysis of the affected extremity. For accurate diagnosis of the nerve pathologies in such conditions, the electrophysiological test can also be very useful.

Here, we summarized the use of several commonly used diagnostic modalities, including radiography, CT, MRI, and electrophysiological tests.

Diagnostic Modalities

1. Plain radiography (X-ray)

After the discovery of X-rays by Wilhelm Conrad Rontgen in 1895, radiography has been considered the first-line imaging modality for diagnosing spine pathologies. With advances in the techniques for radiography over time, the diagnostic value of radiographs also improved, and it provides important information for most spinal diseases, from trauma assessment, determination of spinal deformity and degeneration, identification of spinal instability, and the identification of abnormal lesions suggestive of malignancy.

Currently, conventional radiography using a hard-copy X-ray film has been replaced by digital radiography (DR) that uses a digital detector and imaging processors in clinical practice. The advantages of DR include improved image quality, speed, accessibility, less radiation exposure, availability of post-imaging processing, quality optimization, and convenient image storage and retrieval. Further, the use of DR enabled more precise and accurate measurement of the spinal alignment status and various spinal parameters [1].

Initial evaluation of plain radiography often begins with the anteroposterior and lateral views of the spinal segment at the area of interest. The need for additional studies, such as oblique, flexion, or extension views, is determined based on the clinical situation. Plain radiography demonstrates the inherent advantages of assessing the structural status in a functional position, especially with the patient in an erect and weight-bearing position. Furthermore, it provides a relatively effective assessment of the spinal instability, with flexion and extension (dynamic) lateral radiography [2]. Moreover, dynamic radiography is helpful for evaluating postoperative stability or radiographic fusion as well as detecting the presence of significant motion or evidence of hardware failure or loosening of the instrumented segment.

The main disadvantage of plain radiography is the superimposition of the soft tissue and bony structures that interfere with accurate interpretation of the spinal osseous structures, especially at the cervico-thoracic junction and cranio-cervical junction. Moreover, it cannot be detected properly with the visualization of the paravertebral soft tissues, spinal cord, and bone marrow involvement.

2. Computed tomography

CT allows good visualization of spinal pathologies, including compression of neural structures and disease of the laterally situated structures (such as foraminal stenosis) [3-5]. Modern spiral CT with multidetector row allows rapid and continuous data acquisition within few seconds [6]. CT is also useful in the detailed evaluation of bony structures of the spine and is highly sensitive for fracture detection. Thus, CT of the spine is the first choice of imaging for screening trauma patients, especially those at high-risk of spinal injuries (Fig. 1) [7,8].

Fig. 1.

Lateral radiograph (A) and sagittal CT images (B–D) of the thoracolumbar spine showing full ankylosis of the spine, suspiciously ankylosing spondylitis, and multiple fractures at T10–12 levels with traumatic subluxation. The fracture site, pattern, and extent can be detected more clearly at CT images than those at lateral radiograph. CT, computed tomography.

Raw CT acquires image data in the axial plane, generates cross-sectional images, and enables sagittal and coronal reconstruction via post-image acquisition processing. This multiplanar reconstruction allows excellent evaluation of the spine, visualization of the bony anatomy of the lesion, demarcation of the extent of bone destruction, and checking of the alignment of the vertebral column [9]. Tissue density can be accentuated via the manual adjustment of the contrast and window levels, and subtle soft tissue abnormalities such as small disc protrusions can be detected. Three-dimensional (3D) volumetric reconstruction allows intuitive illustrations for clinicians. In particular, 3D reconstructed images of the complex structures involving the bone and soft tissues, such as the occipitocervical junction and C1–2 level, are helpful for establishing an accurate diagnosis and presurgical planning (Fig. 2) [10].

Fig. 2.

(A, B) Cervical spine magnetic resonance imaging showing posteriorly subluxation of C2 odontoid process and signal change at the spinal cord at C1–2 level. (C, D) Three-dimensional reconstructed computed tomography images at C1–2 level showing bony pathologies as well as surrounding structures (especially, course, proximity, and other abnormalities of vertebral artery).

CT is useful for evaluating posterior elements and bony changes, such as those in Baastrup’s disease [11,12]. Moreover, CT allows easy evaluation of the postoperative status, such as verification of whether spinal fusion has been achieved, locating of the implanted materials, and identification of the hardware-related complications or implant loosening [13]. In particular, CT is superior to MRI in distinguishing the calcified pathology from the surrounding soft tissue, such as OPLL [14,15]. However, its ability to evaluate soft tissue in the spine, especially in neural structures and ligaments, is limited, and it is less sensitive than MRI.

Patients are usually requested to assume a supine position in a CT machine to minimize spine movement. Therefore, limitations to the evaluation of real spinal pathologies that are affected by gravity and standing posture exist, such as spinal stenosis related to spondylolisthesis.

3. Magnetic resonance imaging

MRI is based on the response of the hydrogen nuclei (protons) in intracellular fluids in an artificial magnetic field (rather than on ionizing radiation), and it produces multiplanar images with excellent anatomical and spatial resolution [16]. The proton is temporarily redirected by the magnetic field, and the application of radiofrequency pulses disturbs this alignment. When the pulse is removed, the proton shifts back to its original steady-state position. The MRI machine can distinguish between tissues via the identification of the differences in the shiftback timing of protons. The signal intensity of each tissue depends on the number of protons that is based on the inherent water content of the tissue. Finally, the location and forms of water, fat, bones, and other materials with different resonances can be visualized.

MRI provides high-resolution images of the bone and soft tissues that can be clearly distinguished. Next, MRI can visualize the entire spine and differentiate between individual structures, such as the vertebral body, intervertebral discs, spinal canals, posterior elements, ligaments, paravertebral muscles, nerve roots, and spinal cord. When the contrast in MRI is based on differences in the longitudinal relaxation time, it is called a “T1-weighted” image. Meanwhile, an MRI image is known as a “T2-weighted” image when the image contrast is based on the difference in transverse relaxation time. Further, the release rates of absorbed energy are different for each tissue, and T1 and T2 sequences can be classified accordingly. The routine protocol for MRI of the spine includes axial and sagittal T1- and T2-weighted images. Additional sequences, such as sagittal T2 sequences with fat suppression (e.g., short tau inversion recovery [STIR]) and contrast-enhanced T1 sequences, can be added as required. Knowledge of the signal intensity pattern of each tissue in the T1 and T2 images is vital for reading and interpreting the MRI images [16].

Tissues with high water content, such as the cerebrospinal fluid (CSF), appear as dark structures in T1 images [16]. In contrast, fat-rich tissues have a short T1 relaxation time, and they exhibit a high signal intensity. However, T2 images show high signal intensity in tissues where the extracellular matrix exhibits a higher water content [17]. Thus, bright CSF is the hallmark of T2 images. Next, T1-weighted images provide excellent anatomical details, including bone marrow changes, osseous structures, disks, and soft tissue. The spinal cord and nerves demonstrate an intermediate signal intensity in T2 images, causing maximal contrast between the CSF and neural tissue.

Fat-suppression technology suppresses the high signal of fat (seen in the bone marrow) and is crucial because it allows excellent visualization of the pathological structures [18]. Among the various fat-suppression techniques, the STIR sequence exhibits a high sensitivity in detecting musculoskeletal pathology as it enables the visualization of subtle edematous changes or lesions in the bone marrow or ligamentous structures [19].

The use of intravenous contrast agents, such as gadolinium (Gd), shortens the relaxation time of the adjacent molecules in the magnetic field. Visualization of the contrast enhancement after Gd injection is best visualized on T1 images as an increased signal intensity. Post-contrast imaging can be used to distinguish between postoperative fibrosis of the epidural scar tissues and recurrent herniation of disk fragments [20]. Moreover, post-contrast images are used to evaluate infections, tumors, arteriovenous malformations, and leptomeningeal diseases (Fig. 3) [21-23].

Fig. 3.

(A–C) Metastatic carcinoma with pathologic fracture on C2 odontoid process. CE T1-weighted MRI (C) showing increased signal intensity of the lesion at C2 odontoid process, that makes detection of the lesion more obviously in comparison with other sequences of images on MRI (A, B). CE, contrast enhanced; MRI, magnetic resonance imaging.

MRI can identify small soft tissue structures in the spine, such as the spinal cord and nerve roots [24-26]. Thus, it is currently the most common method used for diagnosing degenerative spine diseases, including diseases of the intervertebral disc, facet joints, ligamentum flavum, posterior longitudinal ligament, and neural foramen. MRI allows excellent evaluation of the degree of central and foraminal stenosis and the degree of other degenerative changes, such as facet arthropathy and degenerative disk disease [26-28].

For trauma patients, MRI is useful for evaluating traumatic disk rupture, ligamentous or spinal cord injury, and intraspinal hematomas [29-31]. Owing to its high sensitivity in identifying bone marrow edema, it is useful for detecting occult fractures, especially with additional fat suppression, such as STIR sequences (Fig. 4) [29]. A T1-weighted image helps to assess the integrity of the ligamentous structures, especially the anterior and posterior longitudinal ligaments, and the epidural hematoma [32-35].

Fig. 4.

Sagittal T1- (A) and T2- (B) weighted magnetic resonance imaging of the lumbar spine showing definite signal change in L1 vertebral body (short arrows) and subtle marrow edema at the L3 vertebra (arrowheads). Additional T2 sagittal image with fat suppression technique showing the previously identified signal changes of L1 and L3 clearer, (C) while the occult fractures of the T11 and T12 vertebrae are clearly revealed due to the definite contrast of marrow edema (long arrows).

MRI is used to evaluate spine tumors, including not only the spinal cord or the nerve root, but also benign and malignant bone tumors [24]. Whenever a tumor is suspected, post-Gd contrast imaging should be performed. MRI should also be considered in patients suspected to present with spinal column infections. The presence of an abnormally increased T2 signal intensity within the intervertebral disc and the presence of Gd enhancement are diagnostic features that indicate the presence of infectious spondylodiscitis. Epidural extension of infection and abscess formation are also easily visible on MRI. In addition, MRI is used for diagnosing inflammatory diseases, such as multiple sclerosis, sarcoidosis, and transverse myelitis, because it can detect spinal cord edema (acute inflammation) or demyelination (chronic inflammation) [36-38].

In order to perform MRI in a position that can best reveal the pathology, dynamic or axial-loading MRI was introduced. Dynamic (neck extension) MRI is more widely used for diagnosing cervical myelopathy. Similar to the cervical canal, the lumbar canal size decreases in the lumbar extension [39,40].

Despite these advantages, MRI is associated with certain problems and safety concerns. Patients with cardiac pacemakers or other embedded ferromagnetic materials cannot undergo MRI [41,42]. In addition, image quality is inevitably affected in patients with implanted metal artifacts, especially devices containing ferrous metals [42]. Further, performing MRI in patients with claustrophobia is difficult because they are unable to stay in the MRI scanner for the entire duration of the examination. CT is superior to MRI for the assessment of the details of osseous or calcified structures [43]. MRI is relatively contraindicated during pregnancy, especially during the first trimester [44]. Contrast administration with Gd carries a rare but specific risk of nephrogenic systemic fibrosis; thus, it should be administered only in patients with suitable renal function (glomerular filtration rate >30 mL/min) [45].

4. Other imaging modalities (EOS, bone scan, and SPECT/CT)

The EOS imaging system, also called a slot-scanning device or slit-beam DR system, is a biplane radiographic imaging system that uses slot-scanning technology wherein the radiation source and detector move in different planes during image acquisition [46,47]. It uses this ultrasensitive multiwire proportional chamber detector to detect the X-rays, thus limiting the dose of X-rays that is absorbed by the patient. EOS can take posteroanterior and lateral images simultaneously and construct the 3D reconstruction of skeletal structures, using algorithms based on statistical modeling and bone shape recognition [48-50]. The images are taken with the patient in the standing position, allowing the examination of the spine and lower extremities under normal weight-bearing conditions [47]. Therefore, suitable indications for the use of EOS for spine are diseases wherein the shape of the deformity varies as per the weight-bearing and gravity, such as scoliosis or kyphosis. EOS imaging exhibits the following limitations [47]. First, EOS does not provide information on soft tissues. Second, the plain images on radiography films present less contrast, resulting in reduced brightness. Third, 3D reconstructions cannot be obtained for pediatric patients aged <6 years. Fourth, 3D angular measurement of severe deformities or congenital anomalies is not possible because the 3D reconstruction process uses a statistical model based on ‘‘normal’’ bones. Finally, the inner structure or architecture of the bone is not considered in 3D reconstructed image because it only involves the outer bone surface.

Radionuclide bone scintigraphy, called bone scan, is one of the most widely used molecular imaging modality for specific spine pathologies [51]. This method is noninvasive, less expensive, causes adverse effects rarely, and allows the confirmation of whole-body bone pathology involving the spine. Bone scan uses several types of radioactive materials (radionuclides) that congregate at specific portions of the bone with highly active areas in metabolism [52]. Thus, the positive area in a bone scan is responsible for metabolically active lesions as the pain source. Considering the principle, bone scan is a valuable option for the following spine pathologies: bone tumor and metastasis, infection, subtle or undetectable fracture, unexplained spine pain unexplainable ton radiography, CT, and MRI, and other bone disorders, such as rickets, avascular necrosis, Paget’s disease, and osteoarthritis [53-57].

Bone scintigraphy with single photon emission compute tomography (SPECT/CT) has recently been introduced to define both, the morphology and physiology simultaneously in a single study [58]. As described earlier, CT can provide precise information about bony structures and anatomical changes of the lesion; however, conventional CT scans cannot represent the physiologic status and cannot implicate and localize the source of the spinal pain [59]. In order to overcome the limitation of the conventional imaging modality, SPECT/CT has been developed for diagnosing spine pathologies, with confirming a site of radiotracer uptake. In particular, the uptake finding enables improved accuracy and diagnostic value of the pathology [60]. Based on the basic concept, previous studies demonstrated that SPECT/CT can be a valuable diagnostic modality for spine disease, especially malignancy, active phase of arthritis, subtle trauma, infection, and postoperative pain caused by pseudoarthrosis, minor infection, and minor factors [61,62].

5. Electrodiagnostic study

Electrodiagnostic study facilitates the diagnosis of spinal disorders. The electrodiagnostic test is a useful tool for diagnosing neuropathy because it can reveal the pathophysiological state of the nerves via the measurement of nerve conduction [63]. Further, electrodiagnostic studies include the nerve conduction velocity study/electromyography (NCV/EMG) and central motor conduction time (CMCT) study.

6. Nerve conduction velocity study or electromyography

NCV/EMG is performed to differentiate peripheral neuropathy from muscular disorders [64,65]. The purpose of NCV/EMG is to assess the extent of peripheral nerve damage and identify the lesion site accurately. In the NCV, electrodes are attached to specific sites on the nerves to record their activity, while stimulation is delivered to the nerves with stimulating electrodes [65]. Then, the time taken for the muscles to contract in response to the stimulation of the nerves, conduction velocity, and amplitude are measured. EMG is a test that evaluates the electrophysiological condition of a muscle with the insertion of a thin needle electrode directly into the muscle tissue [66]. Electrophysiological changes occur in a muscle if nerve damage or an abnormality in the muscle itself is present, and needle electrodes are used to examine such changes [66]. NCV/EMG is commonly used for determining the presence or absence of cervical or lumbar radiculopathy; however, no abnormal findings are observed in mild radiculopathy [67]. Furthermore, early stages of neuropathy and chronic neuropathy that persisted for >1 year are not found positive on NCV/EMG [68]. If radiculopathy is detected on NCV/EMG, it suggests that the neuropathy is significant and persisted past the acute stage (Fig. 5). An additional use of NCV/EMG is in cases of radiculopathy at multiple levels (as detected on CT/MRI) to determine the levels to be treated. However, NCV/EMG from the upper limb cannot detect radiculopathy at C4 or a higher level. Further, it cannot differentiate between radiculopathy at C8 and T1; therefore, a diagnosis of C8/T1 radiculopathy was established in both the cases. In a similar manner, in the lower limb, radiculopathies at L2 and L3 cannot be differentiated from each other, and a diagnosis of L2/L3 radiculopathy was established in both the cases. NCV/EMG is useful not only for diagnosing radiculopathy, but also for distinguishing various disorders that can cause pain and motor weakness in the upper or lower limbs [64,69]. Motor neuron disease presents with a clinical pattern similar to that observed in radiculopathy, and NCV/EMG can help differentiate between the two conditions. Moreover, NCV/EMG can help differentiate peripheral nerve disorders, radiculopathy, and myopathy, thus enabling an accurate diagnosis that would allow appropriate treatment.

Fig. 5.

MRI and EMG of a 46-male patients having right lumbar radicular pain. Both examinations were conducted 1 month after the symptom onset. (A, B) T2-weighted MRIs at L4–5 disc level showed right central protrusion type disc herniation. (C) Positive sharp waves are manifested on right lumbar paraspinals and the muscles (right tensor fascia latae, tibialis anterior, and peroneus longus) innervated by right L5 nerve root, which is indicative finding of right L5 radiculopathy. MRI, magnetic resonance imaging; EMG, electromyography; Fib., fibrillation; Insert. ac., insertional activity; Bizz, bizzar potential; NMU, normal motor unit; LMU, large motor unit; Long po., long duration polyphasic potential; Short po., short duration polyphasic potential; Interf. pat., interference pattern.

7. Central motor conduction time study

CMCT is a test based on motor evoked potentials (MEPs), and it is used to determine the presence or absence of pathology in the brain and the spine [70]. In order to induce an MEP, electrodes are attached to the muscles in the upper or lower limbs, and magnetic stimulation is delivered to the scalp [70]. Electric stimulation is initiated in the corticospinal tract of the brain cortex and is delivered to the muscles in the limb where the electrodes are attached, inducing muscle contraction. Muscle contractions are recorded in the form of MEPs on the monitor; then, the MEP amplitude and latency are calculated. CMCT is estimated based on the MEP latency. The conduction velocity from the cerebral cortex to the spinal nerve root (that is, between the brain and spine) can be estimated by subtracting the latency of nerve conduction between the spinal nerve root around the intervertebral foramen and the muscle where an electrode is attached from the latency of nerve conduction from the cerebral cortex to the muscle via the corticospinal tract with magnetic stimulation. Slowed conduction velocity indicates the presence of a central nervous system disorder. Thus, a CMCT study is useful for determining whether a central nervous system disorder is present; however, it includes a limitation in that minor lesions can be missed because of false negative results.

Conclusions

Accurate diagnosis and proper management of spinal disease is necessary; however, it is occasionally challenging. Next, spine physicians can use several diagnostic imaging options, such as radiography, CT, MRI, and electrophysiological test. Patient (or case)-specific selection of the diagnostic modality is vital because it can help in proper patient management and accurate determination of the prognosis. Therefore, being aware of the various diagnostic modalities of the spine is important in order to be able to determine the best approach for each patient.

Notes

No potential conflict of interest relevant to this article was reported.

References

1. Bansal GJ. Digital radiography. A comparison with modern conventional imaging. Postgrad Med J 2006;82:425–8.
2. Leone A, Guglielmi G, Cassar-Pullicino VN, Bonomo L. Lumbar intervertebral instability: a review. Radiology 2007;245:62–77.
3. Jahnke RW, Hart BL. Cervical stenosis, spondylosis, and herniated disc disease. Radiol Clin North Am 1991;29:777–91.
4. Landman JA, Hoffman JC Jr, Braun IF, Barrow DL. Value of computed tomographic myelography in the recognition of cervical herniated disk. AJNR Am J Neuroradiol 1984;5:391–4.
5. Simon JE, Lukin RR. Diskogenic disease of the cervical spine. Semin Roentgenol 1988;23:118–24.
6. Chawla S. Multidetector computed tomography imaging of the spine. J Comput Assist Tomogr 2004;28 Suppl 1:S28–31.
7. Blackmore CC, Mann FA, Wilson AJ. Helical CT in the primary trauma evaluation of the cervical spine: an evidence-based approach. Skeletal Radiol 2000;29:632–9.
8. Holmes JF, Akkinepalli R. Computed tomography versus plain radiography to screen for cervical spine injury: a meta-analysis. J Trauma 2005;58:902–5.
9. Newton PO, Hahn GW, Fricka KB, Wenger DR. Utility of three-dimensional and multiplanar reformatted computed tomography for evaluation of pediatric congenital spine abnormalities. Spine (Phila Pa 1976) 2002;27:844–50.
10. N V A, Avinash M, K S S, Shetty AP, Kanna RM, Rajasekaran S. Congenital osseous anomalies of the cervical spine: occurrence, morphological characteristics, embryological basis and clinical significance: a computed tomography based study. Asian Spine J 2019;13:535–43.
11. Yolcu YU, Lehman VT, Bhatti AU, Goyal A, Alvi MA, Bydon M. Use of hybrid imaging techniques in diagnosis of facet joint arthropathy: a narrative review of three modalities. World Neurosurg 2020;134:201–10.
12. Kwong Y, Rao N, Latief K. MDCT findings in Baastrup disease: disease or normal feature of the aging spine? AJR Am J Roentgenol 2011;196:1156–9.
13. Ghodasara N, Yi PH, Clark K, Fishman EK, Farshad M, Fritz J. Postoperative spinal CT: what the radiologist needs to know. Radiographics 2019;39:1840–61.
14. Selopranoto US, Soo MY, Fearnside MR, Cummine JL. Ossification of the posterior longitudinal ligament of the cervical spine. J Clin Neurosci 1997;4:209–17.
15. Harsh GR 4th, Sypert GW, Weinstein PR, Ross DA, Wilson CB. Cervical spine stenosis secondary to ossification of the posterior longitudinal ligament. J Neurosurg 1987;67:349–57.
16. Hartley KG, Damon BM, Patterson GT, Long JH, Holt GE. MRI techniques: a review and update for the orthopaedic surgeon. J Am Acad Orthop Surg 2012;20:775–87.
17. Chavhan GB, Babyn PS, Thomas B, Shroff MM, Haacke EM. Principles, techniques, and applications of T2*-based MR imaging and its special applications. Radiographics 2009;29:1433–49.
18. Delfaut EM, Beltran J, Johnson G, Rousseau J, Marchandise X, Cotten A. Fat suppression in MR imaging:techniques and pitfalls. Radiographics 1999;19:373–82.
19. Alyas F, Saifuddin A, Connell D. MR imaging evaluation of the bone marrow and marrow infiltrative disorders of the lumbar spine. Magn Reson Imaging Clin N Am 2007;15:199–219.
20. Haughton V, Schreibman K, De Smet A. Contrast between scar and recurrent herniated disk on contrastenhanced MR images. AJNR Am J Neuroradiol 2002;23:1652–6.
21. Rubin JB, Enzmann DR, Wright A. CSF-gated MR imaging of the spine: theory and clinical implementation. Radiology 1987;163:784–92.
22. Park J, Ham DW, Kwon BT, Park SM, Kim HJ, Yeom JS. Minimally invasive spine surgery: techniques, technologies, and indications. Asian Spine J 2020;14:694–701.
23. Modic MT, Feiglin DH, Piraino DW, et al. Vertebral osteomyelitis: assessment using MR. Radiology 1985;157:157–66.
24. Bradley WG Jr, Waluch V, Yadley RA, Wycoff RR. Comparison of CT and MR in 400 patients with suspected disease of the brain and cervical spinal cord. Radiology 1984;152:695–702.
25. Pfirrmann CW, Dora C, Schmid MR, Zanetti M, Hodler J, Boos N. MR image-based grading of lumbar nerve root compromise due to disk herniation: reliability study with surgical correlation. Radiology 2004;230:583–8.
26. Lee GY, Lee JW, Choi HS, Oh KJ, Kang HS. A new grading system of lumbar central canal stenosis on MRI: an easy and reliable method. Skeletal Radiol 2011;40:1033–9.
27. Lee S, Lee JW, Yeom JS, et al. A practical MRI grading system for lumbar foraminal stenosis. AJR Am J Roentgenol 2010;194:1095–8.
28. Park HJ, Kim JH, Lee JW, et al. Clinical correlation of a new and practical magnetic resonance grading system for cervical foraminal stenosis assessment. Acta Radiol 2015;56:727–32.
29. Kaniewska M, de Beus JM, Ahlhelm F, et al. Whole spine localizers of magnetic resonance imaging detect unexpected vertebral fractures. Acta Radiol 2019;60:742–8.
30. Wang B, Fintelmann FJ, Kamath RS, Kattapuram SV, Rosenthal DI. Limited magnetic resonance imaging of the lumbar spine has high sensitivity for detection of acute fractures, infection, and malignancy. Skeletal Radiol 2016;45:1687–93.
31. Williams RL, Hardman JA, Lyons K. MR imaging of suspected acute spinal instability. Injury 1998;29:109–13.
32. Ricart PA, Verma R, Fineberg SJ, et al. Post-traumatic cervical spine epidural hematoma: incidence and risk factors. Injury 2017;48:2529–33.
33. Kumar Y, Hayashi D. Role of magnetic resonance imaging in acute spinal trauma: a pictorial review. BMC Musculoskelet Disord 2016;17:310.
34. Tan J, Shen L, Fang L, et al. Correlations between posterior longitudinal injury and parameters of vertebral body damage. J Surg Res 2015;199:552–6.
35. Henninger B, Kaser V, Ostermann S, et al. Cervical disc and ligamentous injury in hyperextension trauma: MRI and intraoperative correlation. J Neuroimaging 2020;30:104–9.
36. DeSanto J, Ross JS. Spine infection/inflammation. Radiol Clin North Am 2011;49:105–27.
37. Cadiou S, Robin F, Guillin R, et al. Spondyloarthritis and sarcoidosis: related or fake friends?: a systematic literature review. Joint Bone Spine 2020;87:579–87.
38. Philpott C, Brotchie P. Comparison of MRI sequences for evaluation of multiple sclerosis of the cervical spinal cord at 3 T. Eur J Radiol 2011;80:780–5.
39. Schmid MR, Stucki G, Duewell S, Wildermuth S, Romanowski B, Hodler J. Changes in cross-sectional measurements of the spinal canal and intervertebral foramina as a function of body position: in vivo studies on an open-configuration MR system. AJR Am J Roentgenol 1999;172:1095–102.
40. Kitagawa T, Fujiwara A, Kobayashi N, Saiki K, Tamai K, Saotome K. Morphologic changes in the cervical neural foramen due to flexion and extension: in vivo imaging study. Spine (Phila Pa 1976) 2004;29:2821–5.
41. Raj V, O’Dwyer R, Pathmanathan R, Vaidhyanath R. MRI and cardiac pacing devices: beware the rules are changing. Br J Radiol 2011;84:857–9.
42. Rudisch A, Kremser C, Peer S, Kathrein A, Judmaier W, Daniaux H. Metallic artifacts in magnetic resonance imaging of patients with spinal fusion: a comparison of implant materials and imaging sequences. Spine (Phila Pa 1976) 1998;23:692–9.
43. Xiong L, Zeng QY, Jinkins JR. CT and MRI characteristics of ossification of the ligamenta flava in the thoracic spine. Eur Radiol 2001;11:1798–802.
44. Patenaude Y, Pugash D, Lim K, et al. The use of magnetic resonance imaging in the obstetric patient. J Obstet Gynaecol Can 2014;36:349–63.
45. Dawson P. Nephrogenic systemic fibrosis: possible mechanisms and imaging management strategies. J Magn Reson Imaging 2008;28:797–804.
46. Harada GK, Siyaji ZK, Younis S, Louie PK, Samartzis D, An HS. Imaging in spine surgery: current concepts and future directions. Spine Surg Relat Res 2019;4:99–110.
47. Melhem E, Assi A, El Rachkidi R, Ghanem I. EOS(R) biplanar X-ray imaging: concept, developments, benefits, and limitations. J Child Orthop 2016;10:1–14.
48. Chaibi Y, Cresson T, Aubert B, et al. Fast 3D reconstruction of the lower limb using a parametric model and statistical inferences and clinical measurements calculation from biplanar X-rays. Comput Methods Biomech Biomed Engin 2012;15:457–66.
49. Humbert L, De Guise JA, Aubert B, Godbout B, Skalli W. 3D reconstruction of the spine from biplanar X-rays using parametric models based on transversal and longitudinal inferences. Med Eng Phys 2009;31:681–7.
50. Dubousset J, Charpak G, Dorion I, et al. A new 2D and 3D imaging approach to musculoskeletal physiology and pathology with low-dose radiation and the standing position: the EOS system. Bull Acad Natl Med 2005;189:287–97.
51. Jordan E, Choe D, Miller T, Chamarthy M, Brook A, Freeman LM. Utility of bone scintigraphy to determine the appropriate vertebral augmentation levels. Clin Nucl Med 2010;35:687–91.
52. Chatziioannou S, Kallergi M, Karampina P, et al. Association between bone scintigraphy features of spinal degeneration and anthropometric and demographic variables. J Back Musculoskelet Rehabil 2015;28:13–8.
53. Acikgoz G, Averill LW. Chronic recurrent multifocal osteomyelitis: typical patterns of bone involvement in whole-body bone scintigraphy. Nucl Med Commun 2014;35:797–807.
54. Demir O, Deniz FE, Oksuz E, Gul SS, Demir O. The role of bone scintigraphy in determining spinal fusion after spinal stabilisation surgery. Turk Neurosurg 2019;29:262–8.
55. Erlemann R. Imaging and differential diagnosis of primary bone tumors and tumor-like lesions of the spine. Eur J Radiol 2006;58:48–67.
56. Gheita TA, Azkalany GS, Kenawy SA, Kandeel AA. Bone scintigraphy in axial seronegative spondyloarthritis patients: role in detection of subclinical peripheral arthritis and disease activity. Int J Rheum Dis 2015;18:553–9.
57. El-Desouki M, Al-Jurayyan N. Bone mineral density and bone scintigraphy in children and adolescents with osteomalacia. Eur J Nucl Med 1997;24:202–5.
58. Papathanassiou D, Bruna-Muraille C, Jouannaud C, Gagneux-Lemoussu L, Eschard JP, Liehn JC. Single-photon emission computed tomography combined with computed tomography (SPECT/CT) in bone diseases. Joint Bone Spine 2009;76:474–80.
59. Deyo RA. Diagnostic evaluation of LBP: reaching a specific diagnosis is often impossible. Arch Intern Med 2002;162:1444–7.
60. Sathekge M, Garcia-Perez O, Paez D, et al. Molecular imaging in musculoskeletal infections with 99mTc-UBI 29-41 SPECT/CT. Ann Nucl Med 2018;32:54–9.
61. McDonald M, Cooper R, Wang MY. Use of computed tomography-single-photon emission computed tomography fusion for diagnosing painful facet arthropathy: technical note. Neurosurg Focus 2007;22:E2.
62. Ryan RJ, Gibson T, Fogelman I. The identification of spinal pathology in chronic low back pain using single photon emission computed tomography. Nucl Med Commun 1992;13:497–502.
63. Valls-Sole J. The utility of electrodiagnostic tests for the assessment of medically unexplained weakness and sensory deficit. Clin Neurophysiol Pract 2016;1:2–8.
64. Kwak SY, Boudier-Reveret M, Chang MC. Watch out for slowly progressive weakness of the distal upper limb: it could be chronic acquired demyelinating neuropathy! Ann Palliat Med 2020;9:1285–7.
65. Lee DG, Chang MC. Dorsal scapular nerve injury after trigger point injection into the rhomboid major muscle: a case report. J Back Musculoskelet Rehabil 2018;31:211–4.
66. Rubin DI. Needle electromyography: basic concepts. Handb Clin Neurol 2019;160:243–56.
67. Singh R, Yadav SK, Sood S, Yadav RK, Rohilla R. Evaluation of the correlation of magnetic resonance imaging and electrodiagnostic findings in chronic low backache patients. Asian J Neurosurg 2018;13:1078–83.
68. Misra UK, Kalita J, Nair PP. Diagnostic approach to peripheral neuropathy. Ann Indian Acad Neurol 2008;11:89–97.
69. Chang MC. Missed diagnosis of chronic inflammatory demyelinating polyneuropathy in a patient with cervical myelopathy due to ossification of posterior longitudinal ligament. Neurol Int 2018;10:7690.
70. Rikita T, Tanaka N, Nakanishi K, et al. The relationship between central motor conduction time and spinal cord compression in patients with cervical spondylotic myelopathy. Spinal Cord 2017;55:419–26.

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Fig. 1.

Lateral radiograph (A) and sagittal CT images (B–D) of the thoracolumbar spine showing full ankylosis of the spine, suspiciously ankylosing spondylitis, and multiple fractures at T10–12 levels with traumatic subluxation. The fracture site, pattern, and extent can be detected more clearly at CT images than those at lateral radiograph. CT, computed tomography.

Fig. 2.

(A, B) Cervical spine magnetic resonance imaging showing posteriorly subluxation of C2 odontoid process and signal change at the spinal cord at C1–2 level. (C, D) Three-dimensional reconstructed computed tomography images at C1–2 level showing bony pathologies as well as surrounding structures (especially, course, proximity, and other abnormalities of vertebral artery).

Fig. 3.

(A–C) Metastatic carcinoma with pathologic fracture on C2 odontoid process. CE T1-weighted MRI (C) showing increased signal intensity of the lesion at C2 odontoid process, that makes detection of the lesion more obviously in comparison with other sequences of images on MRI (A, B). CE, contrast enhanced; MRI, magnetic resonance imaging.

Fig. 4.

Sagittal T1- (A) and T2- (B) weighted magnetic resonance imaging of the lumbar spine showing definite signal change in L1 vertebral body (short arrows) and subtle marrow edema at the L3 vertebra (arrowheads). Additional T2 sagittal image with fat suppression technique showing the previously identified signal changes of L1 and L3 clearer, (C) while the occult fractures of the T11 and T12 vertebrae are clearly revealed due to the definite contrast of marrow edema (long arrows).

Fig. 5.

MRI and EMG of a 46-male patients having right lumbar radicular pain. Both examinations were conducted 1 month after the symptom onset. (A, B) T2-weighted MRIs at L4–5 disc level showed right central protrusion type disc herniation. (C) Positive sharp waves are manifested on right lumbar paraspinals and the muscles (right tensor fascia latae, tibialis anterior, and peroneus longus) innervated by right L5 nerve root, which is indicative finding of right L5 radiculopathy. MRI, magnetic resonance imaging; EMG, electromyography; Fib., fibrillation; Insert. ac., insertional activity; Bizz, bizzar potential; NMU, normal motor unit; LMU, large motor unit; Long po., long duration polyphasic potential; Short po., short duration polyphasic potential; Interf. pat., interference pattern.