What Is Considered Severe Scoliosis? A Clear Guide

Scoliosis severity is determined by curve size and treatment plans are crafted in response. A number of measurements are taken during a patient’s initial scoliosis X-ray; their accuracy is crucial. Severe scoliosis involves larger curves that are more complex to treat.

Scoliosis severity ranges from mild to severe and is based on the size of the unnatural spinal curve. While there are additional factors that shape a patient’s scoliosis severity and rate of progression, a patient’s Cobb angle measurement classifies scoliosis as mild, moderate, or severe.

Severe scoliosis requires a more comprehensive treatment plan than mild cases.

Severe Scoliosis

Severe scoliosis involves larger curves, and treatment plans are shaped around curve size and severity.

Because scoliosis is progressive, even cases initially diagnosed as mild or moderate scoliosis can change over time, likely to become severe if left untreated, but scoliosis can be highly treatable, when plans are proactive and work towards preventing mild cases from becoming severe (1).

The main trigger for progression is growth, so cases of childhood scoliosis can involve rapid scoliosis progression. Adolescent idiopathic scoliosis is the most prevalent form, and due to the rapid nature of pubescent growth spurts, adolescent scoliosis can become severe quickly (1, 2).

Severe scoliosis is more complex to treat than mild scoliosis and moderate cases, so the goal is to keep mild cases mild and prevent further curve progression and increasing symptoms (1).

Severe Scoliosis Symptoms

Severe scoliosis symptoms can be overt (3). Scoliosis can be pre-existing or develop fresh in adulthood as degenerative de Novo scoliosis (4).

Scoliosis affects all ages and most commonly develops during adolescence as adolescent idiopathic scoliosis, and the main symptoms of severe childhood scoliosis are overt postural and mobility changes (2).

The larger the size of the spine’s unnatural lateral spinal curve, the more severe the scoliosis, and the more noticeable symptoms are going to be. Another benefit to treating scoliosis proactively and working towards preventing progression is minimizing the potential effects and complications of severe scoliosis (1).

While there are a number of factors that shape a patient’s experience of scoliosis and treatment needs, determining condition severity accurately is an important first step towards a positive treatment outcome.

How is Scoliosis Severity Determined?

A measurement known as Cobb angle assesses the degree of scoliosis, and an X-ray is needed to measure a patient’s Cobb angle, assess, and diagnose scoliosis (5).

Cobb angle measurement is the most widely-used method for assessing scoliosis. Smaller mild curves are measured at less than 20 degrees, and curves more than 35 degrees are diagnosed as moderate scoliosis; curves measuring more than 60 degrees are considered severe (5).

The higher a Cobb angle, the more severe the scoliosis, and the more complex it can be to treat (5). The benefit of diagnosing and treating scoliosis with early intervention is the potential to prevent mild and moderate curves from becoming severe (1).

Cobb Angle Measurement Accuracy

A patient’s Cobb angle is a key piece of information used to quantify curve magnitude and guide treatment plans, so it needs to be as precise and accurate a measurement as possible (5).

Determining a Cobb angle involves locating the most-tilted vertebrae of the curve. Lines are drawn from the endplates of the most misaligned vertebrae, and the intersecting angle is represented in degrees (5).

Many treatment decisions are based on comparisons between a patient’s Cobb angle at the time of diagnosis and how/if it changes throughout the course of treatment; in childhood scoliosis treatment, there is also a focus on how a patient’s Cobb angle measurement responds to growth (5, 6).

In addition to Cobb angle, the angle of trunk rotation, curve location, scoliosis type, and patient age are additional key factors shaping the course of treatment, and the results of a patient’s initial scoliosis X-ray provides most of this information (5, 7).

Scoliosis X-Ray

X-ray imaging is needed to diagnose scoliosis, determine its severity, the degree of rotation, where the curve is located, predict progression, and assess overall spinal health and function (7).

When scoliosis is severe, a large curve is involved, and scoliosis that develops in the thoracic spine is the most likely to progress quickly and become severe (8).

In older adults, the spine’s balance and stability need to be accurately assessed for fall-prevention purposes, and in children, X-rays can also assess bone maturity to predict the rate of curve progression (9, 10).

Scoliosis isn’t static; it changes over time. As a progressive condition triggered by growth, a customized treatment plan needs to allow for adjustments based on how a patient’s curve is responding to treatment and/or growth (6).

Patients should be aware that determining a Cobb angle measurement isn’t a simple process, and even a minor variance of a degree is significant, when it comes to customizing treatment plans for precise results (5).

Standing X-rays are recommended for accuracy as the curve flattens out when the patient is lying down, and it’s also important to measure the spine while it’s supporting body weight and subject to gravitational pressure (5).

So severe scoliosis cases involve large curves that commonly involve overt symptoms, and while the goal is always early diagnosis and intervention, all severity levels require treatment (1).

Severe Scoliosis Treatment

Correcting severe scoliosis can be challenging due to spinal rigidity; as scoliosis progresses, the spine becomes increasingly rigid; this is a primary benefit of starting treatment early, when the spine’s position can be more-easily improved and corrected (11).

Severe scoliosis cases can involve patients with typical types, atypical and rare types, patients whose scoliosis has progressed slowly over time, patients whose scoliosis has progressed rapidly, and cases that have developed later in life due to degenerative instability (2, 4, 12).

Most cases of scoliosis involve idiopathic scoliosis, considered typical, and less-common types are associated with known causes such as neuromuscular scoliosis caused by the presence of a neuromuscular condition like cerebral palsy; these cases can be among the most severe and complex to treat because the neuromuscular condition has to be addressed to impact the scoliosis (12).

Most cases of adult scoliosis involve idiopathic scoliosis that’s pre-existing from adolescence, and older adults can develop degenerative de novo scoliosis later in life, and because degenerative scoliosis is caused by degenerative instability, most cases are progressive and painful (4, 9).

Treatment for adult scoliosis focuses on increasing the spine’s alignment, balance, and stability for fall prevention and pain relief (4).

Treatment for childhood scoliosis focuses on counteracting progression during growth through curvature reductions (6).

While milder cases may respond to scoliosis-specific rehabilitative exercise and/or the prescription of part-time corrective bracing, with moderate scoliosis curves more than 35 degree, full-time corrective bracing is often favored as the primary form of treatment over scoliosis-specific exercise alone (13).

A ScoliBrace® can further support 3-dimensional improvements by maintaining the spine and body’s straight and upright posture (13).

For severe curves of more than 60 degrees, surgical treatment may be necessary, and this most often involves spinal fusion surgery that realigns the spine and holds it in place with attached rods (11).

A goal of proactive nonsurgical treatment options is to help patients avoid the need for surgical intervention (1).

Conclusion

When scoliosis is diagnosed early and treated proactively through scoliosis-specific physical therapy and corrective bracing, the potential for a successful nonsurgical treatment outcome is more likely.

A diagnosis of mild scoliosis doesn’t mean it will stay mild, not without the help of a proactive customized treatment plan.

As a progressive spinal condition, treatment guarantees can’t be given, and treatment needs are ongoing, but many cases of scoliosis are highly treatable, and the sooner treatment is started, and the more customized it is, the better.

The best way to minimize the potential effects and complications of scoliosis is by preventing mild and moderate cases from becoming severe.

References:

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