science

Vertebral augmentation

Vertebral augmentation is a science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Vertebral augmentation rather than just read about it. In short: Vertebral augmentation, including vertebroplasty and kyphoplasty, refers to similar percutaneous spinal procedures in which bone cement is injected through a small hole in the skin into a fractured vertebra in order to relieve back pain caused by a vertebral compression fracture. After decades of medical research into the efficacy and safety of vertebral augmentation, there is still a lack of consensus regarding cer…

Key takeaways

Vertebral augmentation belongs to science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Vertebral augmentation to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Vertebral augmentation from memory before moving on to harder problems.

Reference excerpt

Vertebral augmentation, including vertebroplasty and kyphoplasty, refers to similar percutaneous spinal procedures in which bone cement is injected through a small hole in the skin into a fractured vertebra in order to relieve back pain caused by a vertebral compression fracture. After decades of medical research into the efficacy and safety of vertebral augmentation, there is still a lack of consensus regarding certain aspects of vertebroplasty and kyphoplasty.

Procedure Vertebroplasty and kyphoplasty are the two most common procedures for spinal augmentation.

Vertebroplasty Vertebroplasty is typically performed by a spine surgeon or interventional radiologist. It is a minimally invasive procedure and patients usually go home the same or next day as the procedure. Patients are given local anesthesia and light sedation for the procedure, though it can be performed using only local anesthetic for patients with medical problems who cannot tolerate sedatives well. During the procedure, bone cement is injected with a biopsy needle into the collapsed or fractured vertebra. The needle is placed with fluoroscopic x-ray guidance. The cement (most commonly poly methyl methacrylate (PMMA), although more modern cements are used as well) quickly hardens and forms a support structure within the vertebra that provide stabilization and strength. The needle makes a small puncture in the patient's skin that is easily covered with a small bandage after the procedure.

Kyphoplasty

Kyphoplasty is a variation of a vertebroplasty which attempts to restore the height and angle of kyphosis of a fractured vertebra (of certain types), followed by its stabilization using injected bone cement. The procedure typically includes the use of a small balloon that is inflated in the vertebral body to create a void within the cancellous bone prior to cement delivery. Once the void is created, the procedure continues in a similar manner as a vertebroplasty, but the bone cement is typically delivered directly into the newly created void. In a 2011 review Medicare contractor NAS determined that there is no difference between vertebroplasty and kyphoplasty, stating, "No clear evidence demonstrates that one procedure is different from another in terms of short- or long-term efficacy, complications, mortality or any other parameter useful for differentiating coverage."

Effectiveness As of 2019, the effectiveness of vertebroplasty is not supported. A 2018 Cochrane review found no role for vertebroplasty for the treatment of acute or sub-acute osteoporotic vertebral fractures. The subjects in these trials had primarily non-acute fractures and prior to the release of the results they were considered the most ideal people to receive the procedure. After trial results were released vertebroplasty advocates pointed out that people with acute vertebral fractures were not investigated. A number of non-blinded trials suggested effectiveness, but the lack of blinding limits what can be concluded from the results and some have been criticized because of being funded by the manufacturer. One analysis has attributed the difference to selection bias. Some have suggested that this procedure only be done in those with fractures less than 8 weeks old; however, analysis of the two blinded trials appear not to support the procedure even in this acute subgroup. Others consider the procedure only appropriate for those with other health problems making rest possibly detrimental, those with metastatic cancer as the cause of the spine fracture, or those who do not improve with conservative management. Evidence does not support a benefit of kyphoplasty over vertebroplasty with respect to pain, but the procedures may differ in restoring lost vertebral height, and in safety issues like cement extravasation (leakage). As with vertebroplasty, several unblinded studies have suggested a benefit from balloon kyphoplasty. As of 2012, no blinded studies have been performed, and since the procedure is a derivative of vertebroplasty, the unsuccessful results of these blinded studies have cast doubt upon the benefit of kyphoplasty generally. Some vertebroplasty practitioners and some health care professional organizations continue to advocate for the procedure. In 2010, the board of directors of the American Academy of Orthopaedic Surgeons released a statement recommending strongly against use of vertebroplasty for osteoporotic spinal compression fractures, while the Australian Medical Services Advisory Committee considers both vertebroplasty and kyphoplasty only to be appropriate in those who have failed to improve after a trial of conservative treatment, with conservative treatment (analgesics primarily) being effective in two-thirds of people. The National Institute for Health and Care Excellence similarly states that the procedure in those with osteoporotic fractures is only recommended as an option if there is severe ongoing pain from a recent fracture even with optimal pain management. Vertebral body stenting, also known by the brand Kiva, is a similar procedure which also has poor evidence to support its use.

Adverse effects

Some of the associated risks are from the leak of acrylic cement to outside of the vertebral body. Although severe complications are extremely rare, infection, bleeding, numbness, tingling, headache, and paralysis may ensue because of misplacement of the needle or cement. This particular risk is decreased by the use of X-ray or other radiological imaging to ensure proper placement of the cement. In those who have fractures due to cancer, the risk of serious adverse events appears to be greater at 2%. The risk of new fractures following these procedures does not appear to be changed; however, evidence is limited, and an increase risk as of 2012 is not ruled out. Pulmonary cement embolism is reported to occur in approximately 2-26% of procedures. It may occur with or without symptoms. Typically, if there are no symptoms, there are no long term issues. Symptoms do occur in about 1 in 2000 procedures. Other adverse effects include spinal cord injury in 0.6 per 1000.

Prevalence In the United States in 2003 approximately 25,000 vertebroplasty procedures were paid for by Medicare. As of 2011/2012 this number may be as high as 70,000-100,000 per year.

… excerpt ends here. Continue reading the full article.

Illustrations

Worked examples

Example 1 — a first encounter with Vertebral augmentation

Start with the simplest possible case. Write down what Vertebral augmentation claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Vertebral augmentation before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Vertebral augmentation ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Vertebral augmentation

In research: Vertebral augmentation appears in science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Vertebral augmentation in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Vertebral augmentation is common in secondary-school and first-year university syllabi. It links to neighbouring topics Bones of the vertebral column, Interventional radiology, Orthopedic surgical procedures, so understanding it makes those chapters shorter.
In everyday life: Look for Vertebral augmentation outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Vertebral augmentation in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Vertebral augmentation means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Vertebral augmentation out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Vertebral augmentation in simple terms?

Why does Vertebral augmentation matter?

Because it connects several science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Vertebral augmentation?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Vertebral augmentation.