Diagnostic imaging of spinal fusion and complications • APPLIED RADIOLOGY (2023)

Dr. Hayeri is a former Research Fellow, Division of MSK Imaging at University of California, Irvine Medical Center, Orange, CA, and Dr. Tehranzadeh is Chief of Radiology at Long Beach VA and Professor Emeritus and Vice Chair of Radiology, Department of Radiological Sciences, University of California, Irvine Medical Center, Orange, CA.

Back pain is the most common cause of limited activity in people younger than 45 years in the United States. It is the second most frequent reason for visits to a physician and ranks fifth as the reason for hospital admission.1 It is estimated that 18% of the U.S. population experience low-back pain each year. Fortunately, in most cases, the underlying pathology is benign and the pain is self-limited. Noninvasive methods of treatment such as physical therapy and pharmacotherapy typically resolve such pain.

Treatment of back pain is the third most common indication for surgical procedures in the nation. Decompression and occasional arthrodesis with frequent instrumentation are the main surgical procedures performed in the U.S.2 It is a common belief that immobilization and/or removal of the painful segment decreases pain. Failed back surgery syndrome (FBSS) is defined as failure to relieve lower back pain symptoms following surgery. In the best of all situations, this syndrome occurs after a minimum of 20% of spine fusion surgeries. The syndrome can result from: mistaken diagnoses, technique error, poor application, inappropriate indication, pseudarthrosis or continued natural progression of disease. This syndrome can be prevented to a large extent by meticulous pre- and intraoperative radiologic examination.3,4 Since the initial description of spinal instrumentation by Harda in 1889 and subsequent spinal fusion surgery by Fred Albee and Russel Hibbs in treatment of spinal tuberculosis in 19115–7 there have been a great many advances in surgical methods and instrumentation, as well as many more indications for fusion. Among current indications are scoliosis, spondylolisthesis, congenital deformities, spinal instability in trauma or by iatrogenic causes (e.g. extensive laminectomy), infection and neoplasm. The current indication for spinal arthrodesis is broad and it includes the category of degenerative disc diseases.3

Postoperative imaging is used to assess disease progression, positioning of instrumentation, possible complications and the extent of bone-graft fusion. Knowledge of the advantages and limitations of different imaging modalities is necessary for optimal evaluation of patients with spinal instrumentation. Radiologists should also be familiar with different surgical methods used in spinal fusion, types of instrumentation and potential complications to properly appraise postoperative images.

Stability is described as resistance of the spine to deformation under physiologic stress. Mulholland8 in a recent review of instability and low-back pain hypothesized that the cause of low-back pain could be due to abnormal disc loading. Currently, the most widely accepted cause of low-back pain and the underlying concept promoting the use of spinal fusion is nonphysiologic movement of the degenerated segment. Most appliances are placed to provide stability during bone fusion, and their function is complete when this has occurred. Be-cause of the morbidity associated with repeated surgery, intact implants are generally left in place for life. Fractured and dislodged implants are often removed because of the need for revision and the potential for migration of the components, leading to substantial soft-tissue or neural injury.

Spinal instrumentation

Surgical implants in spinal surgeries are used to stabilize the spine, replace the defective parts and maintain anatomic reduction. Internal spinal instrumentation has undergone considerable advances during the last century. Radiologists should be able to identify the devices most commonly used and understand their biomedical principles and specifications.

Common devices

Rods, plates and rectangles

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Rods can extend to single or multiple spine segments. They can be single or double, straight, L-shaped or can be cut and fashioned as required. They are attached to the spine by hooks, pedicle screws or sublaminar or interspinous wires or cables. Rods are usually preferred over plates for multisegment fusion because of their ability to span a long segment. The Hartshill rectangle is seldom used today. It is a stainless-steel rectangle that attaches to the spine by sublaminar wires and occasionally interspinous wires. Various shapes of plates in different sizes have been developed for anterior or posterior spine fusion.9–11 Some of the commonly used instruments and systems, and their specifications, are summarized in Table 1.

Translaminar or facet screws

These devices can be used when posterior spinal elements are intact. They attach the lamina of 2 adjacent vertebrae.

Interbody spacers

Interbody spacers could be solid (ramp) or hollow (cages). Cages are filled with bone-graft material and inserted into the intervertebral space or replace a vertebra after its removal (i.e. corpectomy). Cages are usually made of titanium carbon fibers, polyetherether ketan (PEEK) or of cortical bone graft. Most cages contain 2 radiopaque markers to identify their position in radiographs and to enable their assessment. They are made in different shapes based on the method of approach to the intervertebral disc.

In anterior interbody fusion (AIF), cages are more round in shape, while in posterior interbody fusion (PIF) they are more rectangular. Transforaminal interbody fusion (TIF) cages are more crescent-shaped. Expandable cylindrical or mesh cages are used in vertebral body replacement procedures.

Cages are usually supported by additional posterior, anterior or lateral instrumentation (i.e. screw with plates or rods) to increase stability. For a standalone interbody fusion cage, the interbody spacer is fixed to the adjacent vertebral body with screws to eliminate the need for additional instrumentation support. Retropulsion of the cage is a possible complication, but is more common in PIF.12 A distance of ≤2 mm between the cage’s posterior marker and the posterior margin of the vertebra should exist to provide reassurance that the cage is not invading the spinal canal.11 Cage subsidence (defined as migration of >3 mm into the adjacent vertebra) and lateral displacement is a disadvantage of using mesh and standalone cages.13–15 The incidence of subsidence is reported from 18% to ≤62.5% in patients who undergo spinal procedures with standalone cervical cages. Expandable cages have broader surface area and duller edges at both ends, which minimize their subsidence and also allow immediate load bearing and stability after corpectomy.16


Dynamic stabilization devices are a new category of instruments that are in various stages of development. They can be used alone or in conjunction with other instrumentation. They act by controlling the abnormal motion and uneven load in segments adjacent to the level of fusion in order to minimize progressive degeneration. Artificial ligaments (e.g. Dynamic Stabilization System [Dynesys], Zimmer Inc., Warsaw, IN), interspinous decompression systems (e.g. X-STOP Spacer, Medtronic Spine, Memphis, TN; and the Wallis Dynamic Posterior Stabilization System, Zimmer Inc., Bordeaux, France), and posterior element replacement systems (e.g. Total Facet Arthroplasty System, Archus Orthopedics, Redmond, WA) are examples of such devices.11

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Surgical methods

Surgical techniques can be divided on the basis of perceived patient morbidity into minimally invasive or traditional-open procedures performed via either an anterior or posterior approach. In interbody fusion, the intervertebral disc or a complete vertebra is removed and replaced with bone graft. Interbody fusion of the spine can be approached anteriorly or posteriorly.

Anterior interbody fusion (AIF) has the advantage of a broader access to the disc space. However, it is limited by potential injury to major vessels and sympathetic nerve chain.17 Oskouian and Johnson reported a 5.8% incidence (12 of 207 patients) of vascular complications in patients who underwent anterior thoracolumbar spine reconstruction procedures.18

Extreme lateral interbody fusion (XLIF) is a newer surgical approach to fuse L1 to L5 and to minimize disadvantages of AIF. Extreme lateral interbody fusion approaches the anterior spine from the flank.

In posterior interbody fusion (PIF) bilateral laminectomies are performed and bone-graft material is inserted into the disc space after the disc is removed. Posterior interbody fusion has the disadvantage of potential injury to nerve roots. Retrograde migration of the graft or cage is also more common with the posterior approach.19

Transforminal interbody fusion (TIF) is a modified PIF that uses a more lateral approach and thus leaves the midline bone structures intact. Min et al. showed both AIF and PIF can produce good outcomes in treating lumbar spondylolisthesis, but AIF is more advantageous in preventing the development of adjacent segment degeneration.20

Overall, Lemcke et al. reported that, with regard to the indications and contraindications, AIF and PIF are unquestionably accepted as up-to-date methods.21 The decision to use AIF or PIF is mainly based on the patient’s presenting pathology, spine anatomy, the surgeon’s experience, history of previous surgery and other conditions that may favor one approach over another (e.g. AIF is difficult in the presence of marked vascular calcification).11,22 Laparoscopic interbody fusion can also be performed; however, compared with open surgery, the overall complication rate is higher (19% vs. 14%, respectively).

Posterolateral fusion is an alternative for interbody fusion. In posterolateral fusion, adjacent vertebrae are fused together by placing the bone-graft material between the transverse processes. In comparison, interbody fusion provides a greater surface area of bone contact and produces a more favorable fusion compared to the posterolateral method.23 Addition of instrumentation to interbody fusion increases success rates to nearly 100%. Using cages in interbody fusions provides more immediate stability during bone graft incorporation.23–25

Imaging of postoperative spine fusion

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Postoperative imaging plays an important role in the assessment of fusion and bone formation. It is also helpful to detect instrument failure and other suspected complications. It is necessary to compare current images with previous studies to identify any subtle changes and disease progression.

Evaluation of the postoperative spine usually begins with conventional radiographs in AP and lateral projections. It usually takes 6 to 9 months for a solid bone fusion to be established radiographically. Conventional radiographs are capable of detecting instrument failure, infection and other causes of failed fusion (Figures 1 through 7). Additional views in lateral flexion and extension are sometimes used to evaluate the presence of motion and the integrity of the fusion.17 Ray defined 6 criteria to radiographically verify a solid fusion:

  1. no motion or <3 degrees of intersegment position change on lateral flexion and extension views,
  2. lack of a lucent area around the implant,
  3. minimal loss of disc height,
  4. no fracture of the instrument, bone graft or vertebrae,
  5. no sclerotic change in the graft or adjacent vertebrae, and
  6. visible osseous formation in or around the cage.26

Sometimes radiographs are nondiagnostic and, based on clinical suspicion and the type of the applied instrument, additional imaging with other modalities may be applied. Currently, computed tomography (CT) with multiplanar reconstruction (MPR) is considered the modality of choice for imaging bony detail and assessing osseous formation and hardware position despite artifact formation. CT is also useful in demonstrating the spinal canal and its alignment and is capable of detecting infection and pseudarthrosis12 (Figure 8). Cook et al. evaluated the extent of bony fusion in an animal model and reported that CT was capable of detecting fusion in 83% of cases, but coincidence of CT image results with histological findings was present in only 14% of specimens and CT significantly overestimated the extent of fusion.27

In another study, Heithoff et al. compared CT images with reoperation findings in symptomatic pseudarthrosis patients and reported that CT was not reliable in identifying these patients.28 Artifacts are the primary disadvantage of CT although artifacts are seen less commonly with titanium implants compared with stainless steel because of the lower beam attenuation coefficient of titanium implants.11

Magnetic resonance imaging (MRI) has been used increasingly in recent years since introduction of titanium-based implants with reduced artifact compared to formerly used stainless-steel devices. These artifacts could be decreased even more by changing imaging parameters such as reducing echo time, increasing bandwidth and decreasing voxel size. Aligning the implant along the axis of the magnetic field also reduces artifact although it is often not completely achievable due to the multidirectional configuration of most hardware. Spin echo sequences are less vulnerable to magnetic susceptibility artifact and give better quality images compared with gradient echo sequences. MRI is useful in detecting infection (Figure 9) and assessing recurrent tumor. MRI is the modality of choice in assessing intraspinal contents. Myelography (Figure 6) is an alternative when MRI is contraindicated or is nondiagnostic because of artifact.

Radionuclide scans are mainly used to detect infection.29 Early stages of pseudarthrosis can also be assessed by increased radionuclide uptake, although this may appear indistinguishable from remodeling. Sonography is used to detect fluid collections and abscesses in the postoperative spinal fusion.17

Spinal fusion instrumentation and complications

Potential complications of spinal surgery vary based on the site of surgery, surgical approach, underlying disease, applied instrumentation, surgeon skill and other clinical factors. Besides the common complications associated with spinal fusion procedures; there are some additional complications based on site, procedure and type of instrumentation.

Hardware fracture (Figures 1 through 4) occurs most commonly as a result of metal fatigue from the repeated stress in spinal movements. The fractured appliance may not be displaced, making its detection difficult. A dislodged or fractured appliance does not necessarily indicate instability or clinical failure of the fusion but is most frequently associated with motion, instability and pseudarthrosis.30 The prominence of the instruments can cause chronic tissue irritation leading to pain, bursa formation and even pressure sores with tissue necrosis. This is an occasional indication for hardware removal.30 There is also a risk of bone resorption around screws or under the implants that are in direct contact with the bone (Figures 5 and 7). This will cause the bones to weaken and predisposes them to fracture and it leads to hardware failure. A loose appliance repeatedly moves and produces bone resorption or erosion. Fused bones are less mobile, which makes the bones vulnerable to fractures above or below the implants if subjected to trauma (Figure 10). Unsuccessful fusion may have other causes such as development of facet arthritis (Figure 6C) or disc disease above or below the fusion level.3 Premature degenerative changes at the disc levels above and below the fused segment can occur due to the reduced number of mobile segments. This complication is reported in 10.2% of patients with posterior fusion and instrumentation.31

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In the cervical spine, potential complications of the posterior approach are mainly neurological and include dural, nerve root or cord injury. The anterior approach is associated with risks of injuring the main vascular structures (carotid and vertebral arteries, jugular vein), causing recurrent damage to the laryngeal nerve or soft tissue, such as the esophagus, trachea or lungs (Figure 11). Postoperative complications include hematoma, pseudomeningocele, infection and instability as a result of laminectomy or incorrect hardware placement. Wires and cables are used as a primary or supplementary instrument in stabilizing the posterior cervical spine (Figure 6). Complications include breakage and slippage of skeletal attachments. Cables (e.g. Songer cable) are much more resistant to fatigue fracture and failure. Plates are used for the anterior and posterior cervical spine. They are also prone to fracture and failure (Figure 2). Screws may break or dislodge or may be misplaced and impinge the cord or nerve root when placed posteriorly.17 In a retrospective study of 1015 patients who underwent anterior cervical discectomy for cervical radiculopathy and/or myelopathy due to degenerative disc disease and/ or cervical spondylosis, Fountas et al. reported the most common postoperative complications to be dysphagia (9.5%), postoperative hematoma (5.6%) and recurrent laryngeal nerve palsy (3.1%).32

Screws should approach the opposite cortex but should not breach it. In anterior-plate screw fixation, the screws may back out and impinge soft tissue (e.g. great vessels, trachea and esophagus) or overpenetrate the posterior cortex and impinge on the cord. These complications can be prevented by using a cervical-spine locking plate with screw caps (e.g. Morscher). This device prevents the screws from backing out and provides increased holding power removing the need for transcortical purchase with the risk of over penetration.

Immobility of the fused segment causes additional stress on adjacent levels of the vertebral column. Ossification of anterior longitudinal ligament and facet disease are common complications of anterior plate and screw fixation (Figure 6).9,17

In anterior fusion of the thoracic or lumbosacral spine, the devices should be laterally located in the anterior column. Neurologic deterioration is the most-feared complication of surgery and may be caused by hardware movement or malpositioned screws (Figures 12 through 15). Incorrect use and later dislodgment or fracture of instruments may also contribute to complications such as instability, fusion failure or pain—with possible resultant neurologic damage. Postoperative neurologic complication due to lumbar instrumentation has been reported in 3% to 11% of patients undergoing spinal procedures. Postoperative neurologic injuries can also be due to cord edema or hematoma and are often self-limited.30 Bone graft material can migrate or hypertrophy resulting in impingement on the spinal canal or neural foramen.17,33,34 Radiographs often show the failed instrument that may have caused neurologic deterioration. Rare but life-threatening complications such as delayed aortic rupture due to instrumentation have also been reported.35

Infection is reported in 1% to 2.4% of patients undergoing lumbar instrumentation. Infection leads to bone destruction and resorption around the implant. On imaging, a lucent area around an implant implies a loose appliance and potential infection (Figures 8 through 9). CT-guided aspiration can be used to isolate the microorganism. Unlike superficial infections that can even be diagnosed clinically, deeper infections such as discitis are sometimes more challenging. Osteomyelitis in adjacent vertebrae, disc collapse and destruction indicate discitis radiographically. Radionuclide-labeled white blood cell scintigraphy and MRI can be helpful to detect infection in early stages.36

Failed fusion with the development of pseudarthrosis is a common end result of implant failure or improper surgical technique (Figures 5 and 6). Its incidence in lumbar instrumentation is reported in 5% to 32% of patients. CT is the optimal method for evaluating a bone graft. A failed fusion with pseudarthrosis formation results in continued stress on the implant, and hardware fracture is inevitable. Suda et al. described radiological risk factors for pseudarthrosis and/or instrument breakage after PLF with pedicle screws to be related to preserved disc height and the presence of segmental kyphosis.37

The risk of pseudarthrosis escalates with increased patient age and smoking. Pseudarthrosis is more common using external braces than internal fixation. The rate of pseudarthrosis is decreased with meticulous surgical technique, including careful facet excision and adequate graft placement. Repair is necessary if the patient presents with implant failure or pain. In asymptomatic patients, intervention may be deferred and the patient’s condition should be followed.38,39


Radiologists face new challenges as the number of, and indications for, spinal surgery grow. Adequate understanding of various surgical techniques and instruments, coupled with improved awareness of the possible complications, are vital when interpreting postoperative studies. Radiologists should carefully compare these critical points with baseline studies to develop a targeted assessment of grafts and hardware. With more familiarity of postoperative spinal images obtained on various modalities and the knowledge of how certain situations (e.g. surgical technique and hardware) contribute to failed back surgery syndrome, radiologists can quickly arrive at a precise diagnosis, permitting appropriate treatment and minimizing patient suffering.

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What is the diagnostic test for spinal fusion? ›

MRI Scan (Magnetic Resonance Imaging)

Similar to an X-ray, the MRI is used to take images of the inside of your body. However, the MRI is able to cut through multiple layers of the spine and show any abnormality of soft tissues, such as nerves and ligaments. This is done using a magnetic field.

What is the best imaging after spinal fusion? ›

Computed Tomography. After spine surgery, CT helps assess instrumentation mispositioning, disruption, and loosening; additionally, it can determine bone continuity and graft fusion.

What are the complications of spinal instrumentation radiographics? ›

Postop- erative complications such as incomplete fusion, hardware failure, suboptimal positioning of in- strumentation, infection, hematoma, and others may be detected at imaging. An assessment with any modality is facilitated by an understanding of spinal biomechanics.

What is the best diagnostic test for spinal disease? ›

MRI. MRI uses a strong magnetic field and radio waves to produce computer-generated images. This test is helpful for looking at the spinal cord and identifying herniated disks, blood clots or other masses that might compress the spinal cord.

What is the best diagnostic test for spinal cord injury? ›

Diagnostic tests for spinal cord injuries may include a CT scan, MRI or X-ray These tests will help the doctors get a better look at abnormalities within the spinal cord. Your doctor will be able to see exactly where the spinal cord injury has occurred.

What is fusion imaging in radiology? ›

Fusion imaging helps in the detection and localization of lesions with low conspicuity on standard B-mode US. US fusion imaging can also be associated with the use of different ultrasound techniques such as color Doppler US, elastography, and contrast-enhanced US (CEUS).

What are examples of fusion imaging? ›

One example of fusion imaging is real-time virtual sonography (RVS), a technique that enables the display of an ultrasound B mode image and CT or MR images in real-time[1].

What is the most widely used imaging modality for diagnosis of spinal diseases? ›

Owing to the previously mentioned limitations of radiography and CT, MRI has been considered the gold standard diagnostic modality for spinal pathologies.

What causes spinal fusion complications years later? ›

A patient may experience recurrent pain many years after a spine fusion surgery. This can happen because the level above or below a segment that has been successfully fused can break down and become a pain generator.

What are the long term problems with spinal fusion? ›

The long-term side effects of spinal fusion involve non-union, hardware failure, Adjacent Segment Disease, and spinal muscle injury. All can require additional surgery. The best way to avoid these complications is to avoid spinal fusion surgery.

What are 3 precautions after spinal fusion surgery? ›

You need to avoid twisting and bending. You also need to avoid lifting, pushing or pulling objects greater than 5 lbs. Lifting and activity restrictions will be gradually removed as the healing process takes place. Remember to keep your spine in the neutral position and maintain good posture throughout the day.

What are three major complications of spinal injury? ›

Long-term complications of a spinal cord injury may include:
  • Inability to regulate blood pressure or body temperature.
  • Increased risk of heart or lung problems.
  • Loss of bladder or bowel control.
  • Paralysis in the arms or legs.
  • Persistent pain.
  • Spasticity, joint contracture.
  • Sexual dysfunction.
Dec 1, 2020

What causes pseudarthrosis after fusion? ›

Causes. Pseudarthrosis occurs when bones fail to fuse with one another after spinal fusion surgery. Factors that reduce the ability of bone-producing cells (called osteoblasts) to produce new bone for fusion increase the risk of Pseudarthrosis.

What is the gold standard imaging for spinal cord injury? ›

MRI Scans have become the golden standard for imaging neurological tissues such as the spinal cord, ligaments, discs, and other soft tissues.

Is MRI or CT scan better for spine? ›

Magnetic resonance imaging produces clearer images compared to a CT scan. In instances when doctors need a view of soft tissues, an MRI is a better option than x-rays or CTs. MRIs can create better pictures of organs and soft tissues, such as torn ligaments and herniated discs, compared to CT images.

What is the best test for lumbar spinal stenosis? ›

A CT or CAT scan (computerized axial tomography) or MRI (magnetic resonance imaging) are good imaging tests that provide detailed information your doctor needs to help diagnose spinal stenosis and its cause.

What diagnostic test for lumbar spinal stenosis? ›

How is lumbar spinal stenosis diagnosed?
  • X-rays of your lumbar spine. These may show bone growths called spurs that push on spinal nerves and/or narrowing of the spinal canal.
  • Imaging tests. A CT scan or MRI scan can give a more detailed look at the spinal canal and nerve structures.
  • Other studies.

What are the 5 signs of a spinal injury? ›

Emergency signs and symptoms of a spinal cord injury after an accident include:
  • Extreme back pain or pressure in your neck, head or back.
  • Weakness, incoordination or paralysis in any part of your body.
  • Numbness, tingling or loss of sensation in your hands, fingers, feet or toes.
  • Loss of bladder or bowel control.
Oct 2, 2021

What is the gold standard test for spinal cord compression? ›

Although CT can diagnose metastatic lesions to vertebrae, MRI is the gold standard for diagnosing spinal cord compression.

What are the three types of radiation in diagnostic imaging? ›

Radiography (x-rays) and dental x-rays. Mammography. DEXA Scans (bone density) CT scans (computed tomography scans)

What is the difference between MRI and RAD Tech? ›

Radiologic technologists specialize in x-ray and computed tomography (CT) imaging. Radiologic technologists, also known as radiographers, perform x rays and other diagnostic imaging examinations on patients. MRI technologists operate magnetic resonance imaging (MRI) scanners to create diagnostic images.

What is the advantage of image fusion? ›

The purpose of image fusion is to combine information from multiple images of the same scene into a single image that ideally contains all the important features from each of the original images. The resulting fused image will be thus more suitable for human and machine perception or for further image processing tasks.

What type of radiation is fusion? ›

A fusion reactor produces helium, which is an inert gas. It also produces and consumes tritium within the plant in a closed circuit. Tritium is radioactive (a beta emitter) but its half life is short. It is only used in low amounts so, unlike long-lived radioactive nuclei, it cannot produce any serious danger.

What are two examples of fusion? ›

Nuclear fusion exists naturally in stars including the Sun, where hydrogen nuclei fuse and create helium while releasing the energy that lights and heats the Earth. Nuclear fusion has also been used in nuclear weapons, but research to harness fusion power for electricity generation is still ongoing.

What is fusion image? ›

The general definition of image fusion is the blending of two or more various images to form a new image by implementing a suitable algorithm [3]. The goal of image fusion increases corresponding information from various sources into one new image. The term fusion means extracting the information in different domains.

What is radiological imaging of the spinal cord called? ›

A myelogram is a diagnostic imaging test generally done by a radiologist. It uses a contrast dye and X-rays or computed tomography (CT) to look for problems in the spinal canal. Problems can develop in the spinal cord, nerve roots, and other tissues. This test is also called myelography.

What types of imaging are used for spine? ›

X-rays of the spine may be performed to evaluate any area of the spine (cervical, thoracic, lumbar, sacral, or coccygeal). Other related procedures that may be used to diagnose spine, back, or neck problems include myelography (myelogram), computed tomography (CT scan), magnetic resonance imaging (MRI), or bone scans.

What are four diagnostic imaging modalities? ›

Each modality is unique in terms of the images it gathers, equipment it uses, and conditions it helps radiologists diagnose. Learn more about our five most common modalities for our various types of imaging tests: X-ray, CT, MRI, ultrasound, and PET.

What is the life expectancy of a spinal fusion? ›

Spinal fusion surgery is, usually, a highly effective procedure. Once the fusion sets, the effects are permanent, so the results can last for life.

How many years does a spinal fusion last? ›

How Many Years Does a Spinal Fusion Last? Spinal fusion is intended to last for life, as the results are permanent. Many spinal fusion patients experience improved pain and mobility for many years after the surgery.

What are the signs of hardware failure after spinal fusion? ›

Hardware Failure After Spinal Fusion

Symptoms of hardware failure are often similar to the symptoms that patients experience before spinal fusion: persistent back pain and/or weakness, tingling, and numbness.

Why should you avoid spinal fusion? ›

Spinal Instability and your pain issues

We don't like to recommend spinal fusion because it does not, in many cases, correct the underlying problems of lumbar spinal instability as many people would think it would. In fact, spinal fusion surgery may increase spinal instability and degeneration.

Can one bend ruin a spinal fusion? ›

Avoid bending at all after a lumbar fusion if possible, as bending or twisting can interfere with the way the fusion heals and even damage the work that was done.

Can you ever bend again after spinal fusion? ›

Once the surgeon confirms on x-ray imaging that the fusion has completely solidified into one bone, a full return to an active lifestyle—including bending, lifting, and twisting—is permitted. This approval typically occurs about 6 months after the surgery, but sometimes it may take closer to 12 months.

What can you never do after spinal fusion? ›

Avoid strenuous activities, such as bicycle riding, jogging, weight lifting, or aerobic exercise, until your doctor says it is okay. Do not drive for 2 to 4 weeks after your surgery or until your doctor says it is okay. Avoid riding in a car for more than 30 minutes at a time for 2 to 4 weeks after surgery.

How long is bed rest after spinal fusion? ›

You will need to restrict your activity for the first 2 weeks, and it will likely be about 4-6 weeks before you can return to your normal routine. It takes most patients about 3 months to feel fully recovered from surgery.

How do you wipe after back surgery? ›

While wiping, bend from the knees rather than at the hips. A long- handled device may help to reach all areas. 4. The use of pre-moistened, flushable wipes is strongly recommended.

Which two parts of the spine have the highest risk of injury? ›

The severity of symptoms can be drastically different based on the region that suffers damage. Further, the two most easily injured portions of the spine are the lumbar and cervical spines.

What are the 2 main commonly injured areas of the spine? ›

The most common sites of injury are the cervical and thoracic areas. SCI is a common cause of lifelong (permanent) disability and death in children and adults.

What are the two most injured parts of the spine? ›

According to John Hopkins Medicine, spinal cord injuries are most common in the cervical region (the upper-most region of the spine, starting just below the skull) and the thoracic region (the middle of the spine, between the cervical and lumbar regions).

What syndrome is associated with fusion? ›

Klippel-Feil syndrome is a bone disorder characterized by the abnormal joining (fusion ) of two or more spinal bones in the neck (cervical vertebrae). The vertebral fusion is present from birth.

What are the signs and symptoms of pseudarthrosis? ›

What are the symptoms of pseudarthrosis? The symptoms of pseudoarthrosis are similar to those of osteoarthritis and include; lack of mobility, persistent pain, joint clicking and in some cases, redness and even fever.

What is pseudarthrosis in radiology? ›

Pseudarthrosis is defined as the absence of solid bony fusion at a minimum follow-up of 6 months after surgery [5, 6]. Pseudarthrosis can be associated with persistent or recurrent back and/or leg pain [7], but can also be asymptomatic [7–9].

What is the most precise diagnostic test for spinal cord injury? ›

Computerized tomography (CT) is a noninvasive procedure that uses x-rays to produce a three-dimensional image of the spine. A CT shows more detail than an X-ray, and can identify the bones in greater detail, and show the nerves, spinal cord, and any possible damage to them.

What diagnostic test confirms spinal cord injury? ›

Diagnostic tests for spinal cord injuries may include a CT scan, MRI or X-ray These tests will help the doctors get a better look at abnormalities within the spinal cord. Your doctor will be able to see exactly where the spinal cord injury has occurred.

Can you do an MRI after spinal fusion? ›

This is a great question! Most people who have metal rods and screws inserted during spinal surgery can have a magnetic resonance imaging (MRI) scan. MRI scanners use a large magnet. If there is loose metal in the body, it can move during the scan.

Can you have MRI with spinal fusion rods? ›

If you have metal or electronic devices in your body such as artificial joints or heart valves, a pacemaker or rods, plates or screws holding bones in place, be sure to tell the technician. Metal may interfere with the magnetic field used to create an MRI image and can cause a safety hazard.

What is the preferred imaging modality for spinal cord dysfunction? ›

As indicated above, computed tomography (CT) is the preferred imaging technique when cervical spine injury is suspected following trauma.

Can you have an MRI if you have metal plates and screws? ›

Pins, plates and metallic joints

Metal that is well secured to the bone, such as hip and knee joint replacements, will not be affected by an MRI. The metal won't heat up or move in response to the machine. But if the metal is near an organ, such as the prostate, distortion could be a problem.

Can you have an MRI with titanium screws in your back? ›

Titanium is a paramagnetic material that is not affected by the magnetic field of MRI. The risk of implant-based complications is very low, and MRI can be safely used in patients with implants.

What can you no longer do after spinal fusion? ›

Avoid strenuous activities, such as bicycle riding, jogging, weight lifting, or aerobic exercise, until your doctor says it is okay. Do not drive for 2 to 4 weeks after your surgery or until your doctor says it is okay. Avoid riding in a car for more than 30 minutes at a time for 2 to 4 weeks after surgery.

What is the alternative to MRI if metal in body? ›

A CT scan may be recommended if a patient can't have an MRI. People with metal implants, pacemakers or other implanted devices shouldn't have an MRI due to the powerful magnet inside the machine. CT scans create images of bones and soft tissues.

Can you go through a metal detector with a spinal fusion? ›

This increase in security has led many patients to wonder if the instrumentation used in their spinal surgery could set off airport metal detectors and require them to undergo additional screening. The most basic answer for individuals undergoing spine surgery is: no, this scenario is unlikely.

Who Cannot have an MRI scan? ›

However, due to the use of the strong magnet, MRI cannot be performed on patients with: Implanted pacemakers. Intracranial aneurysm clips. Cochlear implants.

When is an MRI contraindicated? ›

Devices or metal foreign bodies that are most likely absolute contraindications include: Pacemaker, defibrillator or wires other than sternal wires – the exact mechanism of malfunction is not certain, but death has been recorded.

Are too many MRIs harmful? ›

Is the procedure safe? MRI is a very safe procedure. As noted above, MRI does not use x-rays. In theory, you could undergo many MRI examinations without any cumulative effects.

What metals are not MRI safe? ›

Projectile or missile effect: Ferrous-based materials, nickel alloys and most stainless steel materials are not compatible with the MRI environment. When these materials are exposed to a strong magnetic field, they can be pulled violently toward the magnetic source.

Can you have a CT scan with metal implants? ›

Certain materials will cause more artifact on CT. For instance, surgical materials such as plastic is usually not a problem. Titanium metal is also less of an issue. Stainless steel however will typically cause significant artifact.


1. AO Spine NA Webinar— Complications and Legal Ramifications in Spine Surgery
(AO Spine North America)
2. Virtual Spine Journal Club - Complications of Cervical Spine Surgery
(Seattle Science Foundation)
3. APSS 3rd Webinar: Complications in Cervical Spine Surgery
(Ortho TV : Orthopaedic Video Channel)
4. Lumbar Spinal Fusions: Is Evidence Based Medicine Science or Nonsense -James S. Harrop, M.D.
(Seattle Science Foundation)
5. Lumbar Laminectomy and Fusion Presented by Spine Nevada, Reno Spine Surgeons and Spine Center
(Swift Institute)
6. How to Order Diagnostic Imaging
(Radiology Education by Joseph W. Owen, MD)


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