INTRODUCTION — Scoliosis is an abnormal lateral curvature of the spine. Although it typically occurs in children and adolescents, adults may develop "de novo" degenerative scoliosis; progression of congenital, early onset, or adolescent idiopathic scoliosis; or scoliosis secondary to another condition (eg, paralysis, trauma, spinal surgery).
The clinical features, evaluation, diagnosis, and management of scoliosis in adults will be reviewed here. Hyperkyphosis and spondylolisthesis are discussed separately. (See "Hyperkyphosis in older persons" and "Subacute and chronic low back pain: Surgical treatment", section on 'Spinal stenosis or degenerative spondylolisthesis'.)
TERMINOLOGY
●Adult spinal deformity – Adult spinal deformity encompasses scoliosis, kyphosis, lordosis, and spondylolisthesis, each of which can lead to imbalance of the structural support of the spinal column [1,2].
●Scoliosis – Adult scoliosis is defined as a lateral curvature of the spine in the coronal plane that is >10° (measured by the Cobb angle (image 1)) in a skeletally mature patient [3]. Curves with Cobb angle ≤10° are considered within normal limits of spinal asymmetry [4].
•The direction (left or right) of the scoliosis is determined by the convexity.
•The location is defined by the vertebral body that is most deviated and rotated from midline (ie, the apical vertebral body) [5]:
-Cervical – C2 to C6
-Cervicothoracic – C7 or T1
-Thoracic – T2 to T11
-Thoracolumbar – T12 or L1
-Lumbar – L2 to L4
-Lumbosacral – L5 or below
●Kyphosis – Kyphosis describes forward curvature of the thoracic spine in the sagittal plane. The degree of kyphosis is measured by the Cobb angle (figure 1), with normal curvature generally considered to be between 30 and 50°. Regional deformity results when the Cobb angle is <30° (known as "straight back syndrome") or >50° (hyperkyphosis, commonly referred to as "dowager hump") [2,6].
●Lordosis – Lordosis refers to the normal posterior curvature of the cervical and lumbar spine in the sagittal plane (figure 2). The degree of lordosis is measured by the Cobb angle. Normal lumbar lordosis is between 35 and 80° [6]. Hypolordosis is defined by lumbar lordosis of <35°. Fixed sagittal imbalance, commonly known as "flatback syndrome," occurs when a hypolordotic spinal deformity prevents a patient from being able to stand up straight [7].
●Spondylolisthesis – Spondylolisthesis is defined as displacement of a vertebral body in relation to the vertebral body below it. The superior vertebral body may be displaced anteriorly (anterolisthesis), laterally lateral (lateral listhesis), or posteriorly (posterolisthesis) (figure 3).
ETIOLOGY — The two most common causes of adult scoliosis are "de novo" scoliosis (scoliosis associated with degenerative changes in patients with no previous history of scoliosis) and progression of adolescent idiopathic, congenital, or early onset scoliosis [8]. Genetic factors are thought to play a role in adolescent idiopathic scoliosis (AIS). (See "Adolescent idiopathic scoliosis: Clinical features, evaluation, and diagnosis", section on 'Etiology'.)
Less commonly, adult scoliosis is secondary to an underlying medical condition, paralysis, trauma, or spinal surgery. Postsurgical spinal deformity may result from weakening of the spine after laminectomy or adjacent level failure after spinal instrumentation and fusion.
Adult scoliosis is sometimes classified according to etiology as follows [4,9]:
●Type I – Primary degenerative (or "de novo") scoliosis
●Type II – Progressive AIS with secondary degenerative changes
●Type III – Scoliosis secondary to another pathologic condition, including Marfan syndrome, Arnold-Chiari malformation, and syringomyelia (table 1A-B)
●Type IIIA – Lumbosacral scoliosis caudal to a previous spine fusion
●Type IIIB – Scoliosis secondary to metabolic bone disease (usually osteoporosis) combined with asymmetric degenerative disease and/or vertebral fracture
PATHOGENESIS — Adult degenerative scoliosis usually begins with asymmetric degeneration of the intervertebral disc and facet joints, which leads to unbalanced loading of the spine [9-13]. Asymmetric degeneration can be accelerated by osteopenia or osteoporosis [14]. Increasing scoliosis may be associated with sagittal imbalance and spondylolisthesis [2,7].
Spinal stenosis and narrowing of the lateral recesses may result from osteophyte formation at the facet joints and intervertebral discs combined with hypertrophy and calcification of the ligamentum flavum and joint capsules (figure 4). Spinal stenosis and nerve root impingement often are more severe at levels affected by both spondylolisthesis and degenerative changes.
Concomitant sagittal imbalance (eg, "flatback syndrome," kyphosis) and spondylolisthesis exacerbate abnormal stress and asymmetric load, contributing to the cycle of progressive spinal deformity [2]. Spondylolisthesis can be degenerative, secondary to abnormal stress and wear on the intervertebral disc and facet joints in patients with long-term scoliosis, or secondary to spondylolysis (a unilateral or bilateral defect in the vertebral pars interarticularis, usually in the lower lumbar vertebrae). Spondylolysis can be associated with trauma (leading to secondary scoliosis) or be congenital. In patients with congenital spondylolysis, spondylolisthesis precedes spinal stenosis.
Although degenerative changes may plateau over time, stenosis can continue to worsen, resulting in increasing radiculopathy and/or neurogenic claudication [3]. (See "Lumbar spinal stenosis: Pathophysiology, clinical features, and diagnosis".)
EPIDEMIOLOGY — The prevalence of adult scoliosis varies with the population studied [15-20]. It is inversely proportional to the magnitude of the curve and increases with age [20,21]. Most patients with scoliosis have minor degrees of curvature that may be asymptomatic.
●Approximately 3 to 4 percent of adolescents have scoliosis, resulting in a similar percentage in young adults. (See "Adolescent idiopathic scoliosis: Clinical features, evaluation, and diagnosis", section on 'Epidemiology'.)
●In a nationally representative sample of adults age 25 to 74, the prevalence of scoliosis was 8.3 percent [17].
●In prospective studies, the prevalence of de novo scoliosis in adults ≥50 years was as high as 68 percent [15,20].
Scoliosis prevalence is similar in males and females [20], but females have a higher risk for deformity progression during adolescence, leading to greater curves in adulthood [22].
CLINICAL PRESENTATION — Patients with adult degenerative scoliosis often are asymptomatic [6,20]. When symptoms are present, it may be difficult to know how much the scoliosis is contributing beyond the arthritis itself. Symptomatic patients are usually ≥50 years of age and may present with [9-11,23,24]:
●Back pain (in up to 90 percent of patients) [25]
●Postural imbalance with difficulties standing and walking
●Symptoms of spinal stenosis in approximately 50 to 89 percent of patients [26,27] (see "Lumbar spinal stenosis: Pathophysiology, clinical features, and diagnosis", section on 'Symptoms')
•Neurogenic claudication – Bilateral pain (often asymmetric), sensory loss, and/or weakness affecting the legs; exacerbated by walking, standing, or certain postures
•Radiculopathy – Pain, numbness, tingling, or weakness that radiates into the legs and/or feet
●Neurologic deficits (eg, weakness, numbness, loss of bowel or bladder control) are rare in adult patients with scoliosis; these patients may have spinal cord compression or cauda equina syndrome and require urgent evaluation (see "Anatomy and localization of spinal cord disorders")
●Concerns about appearance (eg, decreased height, change in posture, asymmetry, change in fit of clothing)
As adult degenerative scoliosis progresses, patients may develop fixed sagittal imbalance (eg, flatback syndrome) [7,24]. (See 'Terminology' above.)
Adult patients with progression of adolescent idiopathic scoliosis or scoliosis secondary to another condition may have presenting complaints similar to those with degenerative scoliosis.
CLINICAL EVALUATION
Objectives — The objectives of the evaluation of the adult with suspected scoliosis are to examine the spine for clinical findings suggestive of scoliosis, determine the etiology (primary degenerative, progression of adolescent idiopathic scoliosis (AIS), or secondary to another condition) and factors contributing to pain (for patients with pain), both of which affect management, including indications for referral [11,24].
Patient history — Important aspects of the history include (table 2):
●Onset – Degenerative adult scoliosis typically has onset at ≥50 years of age as degenerative changes in the spine progress. AIS has onset in adolescence, though symptoms may develop later in life. The onset of scoliosis secondary to an underlying condition varies with the condition.
●Change in posture or balance – Patient-reported change in posture or trunk balance may indicate degenerative or fracture-related vertebral body collapse or buckling of one or more intervertebral discs
●Loss of height – It can be helpful to ask the patient if they remember how tall they were when they obtained their driver's license or when they graduated from high school and compare that to current height. Tracking adult height is also helpful in detecting progressive spinal deformity.
For patients ≥40 years, loss of height ≥0.5 inches (1.3 cm) per decade may indicate osteoporotic compression fracture or progression of scoliosis.
●Characterization of pain – Pain related to spinal deformity should be assessed by:
•Location – Have the patient point to specific areas that are painful to determine the exact location.
-Axial pain in the cervical, thoracic, or lumbar spine may indicate the anatomic site of vertebral collapse
-Pain over the scoliotic convexity may be related to muscle fatigue and spasm [9,24]
-Radiation to the legs suggests radiculopathy or spinal stenosis
•Severity – The severity of pain does not correlate well with the severity of imaging findings or potentially serious causes of pain such as neoplasm, fracture, infection, or other serious pathology that require additional evaluation. (See "Evaluation of low back pain in adults", section on 'Serious etiologies'.)
•Aggravating/relieving factors
-Pain caused by scoliosis is aggravated with exertion and is often relieved by lying supine or bracing (which eliminates or decreases the effect of gravity) [15,24]
●Associated symptoms
•"Red flag signs" – Progressive weakness, clumsiness, numbness, or loss of bowel or bladder control – with or without numbness or shooting extremity pain – suggest a neurologic cause and may require urgent evaluation and possible decompressive surgery for cauda equina syndrome or myelopathy. (See "Anatomy and localization of spinal cord disorders", section on 'Cauda equina syndrome'.)
•Isolated numbness or shooting pain in the legs – Suggests lumbosacral radiculopathy. (See "Acute lumbosacral radiculopathy: Pathophysiology, clinical features, and diagnosis".)
•Shortness of breath – Rarely, restricted cardiopulmonary function is the presenting symptom of thoracic scoliosis [1]. Severe thoracic scoliosis (>60°) and hypokyphosis may decrease cardiorespiratory function by diminishing the size of the chest cavity and restricting normal rib movement, or from restricted movement of the diaphragm due to upward pressure of intra-abdominal contents from thoracolumbar scoliosis curve buckling [28-31].
●Past medical history
•Previous spine surgeries
-Previous laminectomy, especially multilevel laminectomy or laminectomy revision surgery, increases the risk of spinal deformity.
-Previous spinal fusion increases the risk of spinal deformity and scoliosis adjacent to the fusion levels.
Patients with previous spinal fusions may develop early-onset adjacent level failure secondary to fractures or disc and ligament failure called proximal junctional failure or distal junctional failure [32]. Adjacent level failure can be is associated with neurologic findings (eg, clumsiness, weakness) and requires urgent referral to prevent permanent neurologic deficits.
•History of hip or knee replacement, infection, or arthritis; hip dysplasia; or lower extremity fracture or amputation – May be associated with leg length discrepancy, which can contribute to spinal deformity.
•Osteoporosis or degenerative disc disease – Increases the risk for curve progression.
•Menopause – Menopause is associated with progression of scoliosis through disc and ligament accelerated breakdown and spine buckling and/or osteoporotic compression fractures because of the loss of bone density associated with hormonal changes. (See "Clinical manifestations and diagnosis of menopause", section on 'Long-term consequences of estrogen deficiency'.)
•History of associated neurologic conditions – Certain neurologic conditions are commonly associated with scoliosis (eg, Chiari II [Arnold-Chiari] malformation, cerebral palsy, Charcot-Marie-Tooth syndrome, syringomyelia, spinal cord injury, polio). (See 'Etiology' above.)
•History of genetic conditions affecting collagen and bone – Genetic conditions that affect collagen and bone (eg, Marfan syndrome, Ehlers-Danlos syndrome) are commonly associated with scoliosis. (See 'Etiology' above.)
●Family history of scoliosis – Idiopathic scoliosis has a genetic component.
Spine examination
●Inspection – The first step is inspection of the standing patient from behind and from the side. Findings that suggest scoliosis include:
•Lateral curvature of the spine with thoracic (picture 1A-B) or lumbar asymmetry; the most common scoliosis curve is a right thoracic, left lumbar double curve, but many other curve configurations occur [4,33] (see 'Terminology' above)
•Head not centered over the sacrum and/or torso not centered over the pelvis in the coronal plane (ie, trunk shift)
•Asymmetry in shoulder or scapulae height, waistline, or distance that the arms hang from the trunk
Other relevant findings include:
•Increased thoracic kyphosis when viewed from the side
-May be seen with osteoporosis or compression fractures and degenerative disc disease
-May be associated with underlying deformity (eg, Scheuermann kyphosis)
•Decreased thoracic kyphosis when viewed from the side
-May be seen with scoliosis and/or previous back surgery
•Decreased lumbar lordosis when viewed from the side ("flatback syndrome")
-Associated with progression of degenerative scoliosis
●Adam's forward bend test – The Adam's forward bend test evaluates the rotational component of scoliosis by observing the patient from the back while he or she bends forward at the waist until the spine is parallel to the floor with feet together, knees straight ahead, and arms hanging freely. Thoracic (rib) or lumbar (loin) prominence on one side is a sign of scoliosis (figure 5) [4,34]. Observing the patient from the side may also identify kyphosis and loss of lumbar lordosis.
For patients unable to perform the standing test, patients with leg length discrepancy, or asymmetric hamstring tightness, Adam's forward bend test can be performed with the patient sitting on a chair. An alternative for patients with leg length discrepancy is to place an appropriate-sized block under the short leg [35].
Inability to bend forward at the waist or decreased range of motion with forward or side bending may be secondary to pain, lumbar muscle spasm, and/or tightness of the hamstrings [1,4,6]. Any of these findings may indicate an underlying cause of scoliosis. Acute lumbar disc herniation can cause significant scoliotic postural changes with trunk shift as the patient leans away from the side of the disc herniation.
●Scoliometer – A scoliometer is used to evaluate asymmetry in the upper thoracic, mid-thoracic, thoracolumbar, or lumbar region. The scoliometer functions similarly to a carpenter's level and is placed along the patient's spine from cephalad to caudad while the patient is in the Adam's forward bend test position (picture 2) [36]. If rotational prominence is present, then the ball in the scoliometer deviates from the center of the device.
The scoliometer measures the angle of trunk rotation, which differs from the Cobb angle. As a general guideline, a scoliometer angle of 7° corresponds to a Cobb angle for scoliosis of 20° [37].
Potential sources of error in scoliometer measurements include ambiguous markings for degree increments, inconsistent identification of the curve apex, and inconsistent performance of the Adam's forward bend test [38].
Inexpensive scoliometer applications are available on mobile devices. Validation studies of scoliometer applications suggested good correlation with traditional scoliometers [39-41].
●Palpation – Palpate for areas of tenderness along the spine and pelvis, and assess if pain is made better or worse with flexion or extension.
•Localized tenderness of the spine may indicate facet arthritis or fracture.
•Localized tenderness of the sacro-iliac joints may indicate sacro-iliac joint arthritis.
•Localized tenderness of pelvis may indicate or a sacral insufficiency fracture in older patients with osteoporosis.
General examination — Aspects of the general examination that are helpful in assessing severity and progression in patients with scoliosis include (table 3):
●Height measurement – It is important to measure the patient's height every year and to review the trend over time. For patients ≥40 years, loss of height ≥0.5 inches (1.3 cm) per decade may indicate osteoporotic compression fracture or buckling progression of deformity.
●Standing posture, trunk balance – The patient's posture should be assessed in the standing position, checking to see if the head and torso are centered over the pelvis in the coronal and sagittal planes.
•In patients with scoliosis, the head and torso lean to one side in the coronal plane.
•In patients with sagittal imbalance, the head and torso are "pitched forward" in the sagittal plane, or "flatback syndrome." There may be associated pelvic retroversion and loss of lordosis, which is identified by flattening of the buttocks [6,10,42-44]. Patients with flexible sagittal imbalance can stand up straight with compensatory flexion of the hips and knees [24]. Patients with fixed sagittal imbalance are no longer able to stand up straight.
●Gait – Gait should be evaluated, including asking the patient to walk on their heels and toes [2]:
•Clumsiness or spasticity may indicate cervical or thoracic myelopathy or neuromuscular disease
•Antalgic gait may indicate nerve root compression
•Imbalance may indicate global (coronal and sagittal) imbalance or lower extremity arthritis
•Need for walker or cane indicates unsteadiness
●Strength, sensation, and reflexes in the upper and lower extremities – Abnormalities may indicate myelopathy, radiculopathy, or other neurologic process. For example:
•Hyperreflexia, pathologic reflexes, and clonus may indicate myelopathy [2].
•Absent or diminished reflexes may indicate radiculopathy.
(See "The detailed neurologic examination in adults".)
●Leg length discrepancy – Leg length discrepancy is assessed by measuring from the anterior superior iliac spine to the caudal edge of medial malleolus bilaterally with the patient in the supine position. Most patients with scoliosis have equal leg lengths but apparent leg length discrepancy because the pelvis tilts to compensate for the lumbar portion of the curve.
Leg length discrepancy may contribute to the pathogenesis of scoliosis through asymmetric loading. (See 'Pathogenesis' above.)
●Signs of congenital genetic condition – Some genetic conditions are associated with spinal deformity, including:
•Marfan syndrome (see "Genetics, clinical features, and diagnosis of Marfan syndrome and related disorders")
•Ehlers-Danlos syndrome (see "Clinical manifestations and diagnosis of Ehlers-Danlos syndromes")
•Neurofibromatosis type 1 (picture 3A-D and table 4) (see "Neurofibromatosis type 1 (NF1): Pathogenesis, clinical features, and diagnosis")
•Spinal dysraphism (see "Myelomeningocele (spina bifida): Anatomy, clinical manifestations, and complications" and "Closed spinal dysraphism: Clinical manifestations, diagnosis, and management", section on 'Musculoskeletal')
Patients with clinical features of these conditions may have scoliosis secondary to the underlying condition. (See 'Etiology' above.)
Quality of life — The patient's quality of life affects management decisions. Worsening quality of life may require additional or more invasive interventions. (See 'Management' below.)
The patient's quality of life can be assessed informally by asking about:
●Pain with various activities
●Whether and for how long the patient is able to stand and walk
●Whether the patient is able to perform activities of daily living (eg, get in and out of bed)
●Self-image/self-consciousness about posture and appearance (eg, leaning to one side, new skin folds under the rib cage)
Validated tools are available to quantitatively assess quality of life and can be used to monitor quality of life over time. These include the Owestry Disability Index (figure 6) [45] and Scoliosis Research Society-22 (available in several languages from the Scoliosis Research Society).
RADIOGRAPHIC EVALUATION — The initial radiographic evaluation for scoliosis (standing posteroanterior [PA] and lateral views of the spine on a 36-inch digital cassette) may be ordered by the primary care clinician. Additional views and/or advanced imaging for patients with symptoms or more severe or progressive scoliosis is usually obtained by the spine specialist as indicated to identify correctable causes of scoliosis, evaluate conditions that should be treated before surgical correction of scoliosis, and to plan surgery.
Radiographs — Radiographs are required to confirm the diagnosis of scoliosis, evaluate the etiology (eg, postsurgical, posttraumatic, congenital (image 2A-B), degenerative (image 3)), determine the curve pattern (picture 1B), measure the magnitude of the curve (Cobb angle), evaluate the extent of degenerative changes (to determine the risk for progression), and assess sagittal balance [10,46].
●Indications – Indications for radiographic evaluation in an adult scoliosis patient include:
•Clinically evident spinal deformity on physical examination
•Scoliometer reading (angle of trunk rotation) of ≥7°
•Curve progression monitoring of patients previously diagnosed with scoliosis
●Views – The initial radiographic evaluation of scoliosis includes standing posteroanterior (PA) and lateral views of the spine on a 36-inch digital cassette that can portray the entire spine.
PA views minimize radiation exposure to the thyroid and breasts. The lateral view assesses spinal deformities in the sagittal plane (eg, kyphosis, loss of lumbar lordosis) and pelvic parameters. In scoliosis patients, lumbar lordosis and thoracic kyphosis often are reduced. Increased thoracic kyphosis may suggest underlying pathology, particularly osteoporosis [2]. Lateral views can also show abnormalities such as spondylolysis and spondylolisthesis.
To accurately measure spinal balance and curvature on PA and lateral radiographs, the patient should be standing with their knees extended, hips relaxed, and fingertips placed on the clavicles [6,47]. Standing radiographs are required because lying down eliminates the effect of gravity, reduces the magnitude of the curve, and limits the ability to assess coronal and sagittal balance. [47-50]. Leg-length discrepancy can be corrected before imaging by using the patient's existing shoe lift or an appropriately sized block or having the patient in a seated position; the radiograph should be labeled to indicate the side and size of the shoe lift or block.
The radiographs should capture the complete spine from the occipital condyles to the femoral heads [6,47,51]. This can be accomplished with either a full-length, 36-inch digital cassette or with low-dose three-dimensional spine imaging (stereoradiography). Although it is not widely available, low-dose three-dimensional spine imaging can provide better understanding of the deformity and include the lower extremities to evaluate the effect of leg lengths and joint contractures [52-54]. If neither a 36-inch cassette nor low-dose three-dimensional stereoradiography is available, separate thoracic and lumbar radiographs can be obtained, but measurement of curves and global balance will be more difficult.
●Radiographic findings of scoliosis – The diagnosis of scoliosis is confirmed by a Cobb angle of >10° of lateral curvature (image 1).
The Cobb angle is the standard for quantifying the magnitude of a curve in scoliosis [55]. The Cobb angle is formed by intersecting a line parallel to the superior end plate of the most tilted cephalad vertebra in a specific curve, with the line parallel to the inferior end plate of the most tilted caudad vertebra of the curve (image 1).
Although the Cobb angle is the accepted standard for measuring scoliosis on radiographs, it has limitations. It does not measure rotational deformity and is not directly proportionate to the severity of scoliosis [37,56]. Variation in measurement error is between 1 and 5° [47,57-59].
Clinicians treating spinal deformity patients must have training and experience in measuring Cobb angles and should have a digital system that includes measurement functions or, at the very least, the capacity for a good-quality paper printout of the digital image to manually measure the Cobb angle [60]. If possible, it is important to use the same method of measurement when comparing Cobb angles over time.
The severity of scoliosis increases with increasing Cobb angle. The severity of trunk shift can be assessed by measuring the distance that the rib cage "overhangs" the lateral border of the iliac crest. The severity of lateral listhesis (often associated with lumbar scoliosis, most commonly at L3-L4) can be measured in millimeters of vertebral body overhang. The severity of rotation can be assessed by examining the degree of asymmetry of the appearance of the pedicles at each level.
●Radiographic measurement of sagittal imbalance – The sagittal vertical axis (SVA) is a measure of sagittal balance. It is the horizontal distance from the C7 plumb line to the posterior superior corner of the end plate of the S1 vertebra (figure 7). SVA ≥4 cm has been associated with increasing pain and disability [55,61].
●Other spinopelvic parameters – A discussion of other radiographic spinopelvic parameters (eg, pelvic incidence, pelvic tilt) is beyond the scope of this review but available from the Scoliosis Research Society.
MRI of the spine — Magnetic resonance imaging (MRI) of the spine is indicated in patients with spinal deformity and clinical or radiographic findings suggestive of intraspinal pathology or who are experiencing neurologic symptoms. MRI may be superior to computed tomography (CT) of the spine for evaluating intervertebral disc herniations and spinal stenosis of the central canal, lateral recess, and/or neural foramen, though the clinical significance of these findings is sometimes unclear. (See "Evaluation of low back pain in adults", section on 'Limited utility of imaging'.)
Relevant MRI findings may include:
●Lumbar spinal stenosis and conditions that cause or aggravate lumbar spinal stenosis (eg, lateral, anterior, or posterior spondylolisthesis, facet osteophytes or cysts, severe ligamentum flavum hypertrophy, spinal fractures or fracture fragments)
●Spinal cord compression (may be difficult to interpret if the spinal deformity is severe)
MRI is more sensitive and specific than myelography in the evaluation of intraspinal anomalies and avoids ionizing radiation [62].
CT of the spine — CT of the spine is useful in evaluating the bony anatomy (eg, osteophytes in the spinal foramen) and integrity of spinal hardware from previous surgery (eg, loose pedicle screws) [47]. CT scans also can provide a more accurate measurement of axial rotation than radiographs, and can be used to measure bone density, but require significantly more ionizing radiation [47,63,64].
Potential indications for CT include:
●Assessment of spinal stenosis and other pathologies in patients who are not candidates for MRI (eg, cochlear implant, certain pacemakers, and spinal cord stimulators)
●Improved assessment of bony anatomy in patients with congenital scoliosis or vertebral fractures
●Assessment of the position and possible loosening of spinal hardware
DIAGNOSIS — Adult scoliosis is a radiologic diagnosis. Criteria for the diagnosis include:
●Lateral (coronal) curvature with Cobb angle of >10°
●Complete closure of the iliac crest epiphysis (Risser 5 (figure 8))
The severity of scoliosis increases with increasing Cobb angle. The curve pattern and associated sagittal deformity can be categorized according to a variety of systems that are used in making decisions about surgery (eg, King-Moe, Lenke, Schwab, Scoliosis Research Society-Schwab) [5,61,65-69]. Discussion of these classification systems is beyond the scope of this review but is available from the Scoliosis Research Society.
CURVE PROGRESSION — Sixty to 70 percent of adult scoliosis patients have some evidence of curve progression. However, the pace of progression is variable. Curves may be stable for many years and then progress suddenly. In a longitudinal study of 200 patients ≥50 years of age with degenerative lumbar scoliosis, curves progressed at an average of 3° per year (range 1 to 6°) [70]. In another longitudinal study, 11 of 42 female patients with degenerative lumbar scoliosis progressed ≥5° during a mean follow-up of 12 years [71].
Progression of curves in patients with a history of adolescent idiopathic scoliosis (AIS) is discussed separately. (See "Adolescent idiopathic scoliosis: Management and prognosis", section on 'Outcome'.)
Factors that appear to increase the risk for progression include:
●Cobb angle >40° [70,72,73].
●Rotation of the apical vertebra [74,75].
●Lumbar curve – Lumbar curves progress more rapidly and to a greater extent than thoracic curves [2,70]. Additional risk factors specific to lumbar curve progression include Cobb angle >30°, lateral listhesis >6 mm, and fixed angulation in the coronal plane of L5 on S1 [10,76].
●History of decompression laminectomy without spinal fusion [77].
●History of spinal fusion (including correction of AIS, particularly those who were fused in a flatback position with a Harrington rod).
MANAGEMENT — Management of scoliosis in adults is individualized according to etiology, severity of symptoms, and quality of life. Pain and functional limitations (eg, increased back and leg pain with walking) play a major role in the decision to undergo surgery for adult scoliosis [78,79].
Primary care management — Pain and/or difficulties with activities of daily living are indications for treatment of adult scoliosis.
Initial treatment with conservative measures is appropriate for patients without "red flag" findings (progressive weakness, clumsiness, numbness, radiating extremity pain, or loss of bowel and bladder control) or progressive neurologic deficits, with stable coronal and sagittal balance, and with stable curves (progression of ≤1° per year) [10,80-83].
The patient and treating clinician must have realistic expectations regarding the benefits and costs of conservative therapy [24,84]. The goal of conservative management is to maintain or improve function, quality of life, and stamina rather than correction of the spinal deformity. Randomized trials of conservative treatments for adult scoliosis are lacking. In observational studies, conservative interventions have been associated with improved pain, posture, balance, and/or self-image in some patients [85-88].
Conservative treatment for scoliosis is similar to conservative treatment for other types of back pain, which is discussed separately. (See "Subacute and chronic low back pain: Nonpharmacologic and pharmacologic treatment".)
In addition to more general conservative therapies (eg, nonnarcotic analgesics, aerobic and core-strengthening exercises), the following interventions are specific to scoliosis:
●Physiotherapeutic scoliosis-specific exercises (PSSE), such as the Schroth technique, may provide reduction of curvature [89] and improve quality of life and appearance [90].
●Modified Pilates exercise programs may improve strength and quality of life [91].
●Shoe lifts for patients with leg-length discrepancy contributing to scoliosis.
●Soft bracing can be used to provide spinal support (which may improve ambulatory function) and short-term pain relief, but a brace will not stop the curve from progressing in an adult scoliosis patient [92]. Custom-molded plastic braces, especially when combined with PSSE, may help halt or reverse curve progression in some patients [93].
●For overweight or obese patients, weight loss reduces the asymmetric load on the spine. (See 'Pathogenesis' above.)
In addition, obesity may mask the severity of spinal deformity and increases the risk of surgical complications [94-96].
●Patients with osteoporosis should be offered treatment for osteoporosis. Osteoporosis can lead to more rapid progression of scoliosis and kyphosis and affects decisions about spinal surgery. Screening, prevention, and treatment of osteoporosis are discussed separately. (See "Screening for osteoporosis in postmenopausal women and men" and "Prevention of osteoporosis" and "Overview of the management of osteoporosis in postmenopausal women" and "Treatment of osteoporosis in men".)
●A four-wheel rolling walker with brakes and seat allows the patient to walk with better posture and balance. It can improve mobility, decrease pain, and reduce the risk of falls.
Indications for referral — Indications for referral to a spine specialist in patients with scoliosis include:
●Persistent pain affecting quality of life despite conservative measures such as analgesia or physical therapy (see 'Primary care management' above)
Earlier surgical intervention may be associated with improved quality of life [97].
●Radicular pain – Neurogenic claudication or sciatica
●Need for serial monitoring of patients with adult spinal deformity due to unexpected height loss and/or posture change suggesting curve progression and/or documented curve progression >4° during adulthood
●Shortness of breath that is thought to be due to spinal deformity
●Progressive weakness, clumsiness, numbness, or loss of bowel or bladder control – These "red flag" signs may indicate acute spinal cord compression or cauda equina syndrome and require urgent referral
Specialist management — Specialist management of the adult patient with scoliosis includes serial monitoring of symptoms, quality of life, and curve magnitude and shared decision making regarding additional interventions, including surgery.
Serial monitoring — Longitudinal radiographic data can be helpful in assessing curve progression over time, and patients should be encouraged to keep copies of their radiographs and measurements. However, the frequency and type of follow-up for patients with adult scoliosis is individualized according to the type of scoliosis (primary degenerative scoliosis, progressive adolescent idiopathic scoliosis, secondary scoliosis), magnitude (as indicated by the Cobb angle), previous interventions, progression, and preference of the treating surgeon.
Serial monitoring of clinical features and radiographs allows the patient and provider to understand the rate of progression. This permits shared decision making regarding the possibility of earlier, less invasive surgical treatment, when appropriate. (See 'Surgical intervention' below.)
The patient's quality of life should also be monitored over time. (See 'Quality of life' above.)
The quality of life in adult scoliosis patients may remain stable for decades. However, in some patients, it may decline gradually, then decrease dramatically over weeks to months, with markedly increased pain, disability, and deformity. For patients who decline despite conservative treatment, earlier specialist referral may prevent patient suffering, decrease use of analgesic medications, and decrease deconditioning.
Injection therapies — Epidural glucocorticoid injection may be reasonable for scoliosis patients with lumbar stenosis with neurogenic claudication or lumbosacral radiculopathy who have not improved with conservative treatment. However, given that most of these patients have degenerative arthritis and spinal stenosis, benefits are limited and short term, as discussed in the related topics. Although the risk of adverse effects is not increased in adult scoliosis patients, the epidural injection may be more challenging than in patients without scoliosis. (See "Subacute and chronic low back pain: Nonsurgical interventional treatment", section on 'Epidural injection' and "Lumbar spinal stenosis: Treatment and prognosis", section on 'Epidural injections'.)
Glucocorticoid injections with or without a local anesthetic into the facet joints have not been shown to be effective in the treatment of low back pain, but they may be helpful in identifying the source of pain for surgical planning [11,24,98]. (See "Subacute and chronic low back pain: Nonsurgical interventional treatment", section on 'Facet joint injection and medial branch block'.)
Surgical intervention — The goals of spinal deformity surgery for scoliosis are to provide relief from pain and neurologic symptoms while maintaining or restoring three-dimensional spinal balance to improve the patient's overall quality of life, including self-image [2,99-101].
Potential indications and/or prerequisites for surgery include:
●Unacceptable and worsening quality of life
●Lack of response to conservative treatments and injection treatments for pain and/or neurologic deficits (if appropriate)
●Surgically-correctable problem(s) such as spinal stenosis and/or spinal buckling/collapse
●Medically able to undergo the procedure
●Fully understands the risks and benefits of the procedure, tailored to their specific situation
The surgical procedure is individualized according to clinical and radiographic findings (eg, source of pain, functional impairment, comorbidities, past surgical history, severity of coronal and sagittal deformity, curve progression) [10].
For patients with isolated radicular and/or neurogenic claudication symptoms, minimally invasive surgery may decompress the symptomatic nerve root while preserving spinal stability. In cases with milder deformity, minimally invasive short segment instrumentation and fusions can be considered with or without decompression.
Randomized trials of surgical interventions for adult scoliosis are lacking. In observational studies, surgical interventions have been associated with improved quality of life, decreased pain, and improved self-image in scoliosis patients [88,102]. However, the potential benefits must be balanced against the risk of surgical complications, including reoperation for instrumentation or graft failure.
In a retrospective review of the Scoliosis Research Society database of 4990 patients undergoing surgery for adult degenerative or idiopathic scoliosis (2004 to 2007), the overall complication rate was 13.4 percent [103]. Dural tear was the most common complication (2.9 percent), followed by implant complication (1.6 percent) and deep wound infection (1.5 percent), acute neurologic deficit (1 percent), superficial wound infection (0.9 percent), delayed neurologic deficit (0.5 percent), wound hematoma (0.4 percent), death (0.3 percent) pulmonary embolus (0.2 percent), and deep venous thrombosis (0.2 percent). The complication rate was increased among patients undergoing osteotomies, revision procedures, and combined anterior/posterior approaches but was not affected by age or type of scoliosis.
Higher complication rates are reported in studies of surgery for adult spinal deformity (not limited to scoliosis). In a systematic review of 93 randomized and observational studies including 11,692 patients who underwent surgery for adult spinal deformity, the mean overall complication rate was 55 percent. Major perioperative complications (eg, neurologic deficit, severe/deep wound infection, instrumentation/graft failure, excessive bleeding) occurred in 18.5 percent, minor perioperative complications (eg, dural tear, ileus/gastrointestinal complication, transient neurologic deficit, superficial wound infection) occurred in 15 percent, and long-term complications (eg, pseudarthrosis, instrumentation/graft failure, adjacent segment degeneration) occurred in 20.5 percent [104]. In a subsequent multicenter prospective study, 72 percent of patients who underwent operative management of adult spinal deformity had at least one complication [88].
SUMMARY AND RECOMMENDATIONS
●Adult scoliosis is defined as a lateral curvature of the spine in the coronal plane that is >10° (measured by the Cobb angle (image 1)) in a skeletally mature patient. It is often accompanied by abnormal curvature in the sagittal plane (eg, hyperkyphosis of the thoracic spine, loss of lumbar lordosis) and/or displacement of one or more vertebral bodies (spondylolisthesis). (See 'Terminology' above.)
●The two most common causes of adult scoliosis are "de novo" scoliosis (scoliosis associated with degenerative changes in patients with no previous history of scoliosis) and progression of adolescent idiopathic scoliosis (AIS). Less commonly, adult scoliosis is secondary to paralysis, trauma, spinal surgery, or other underlying condition. The prevalence scoliosis increases with age and in adults ≥50 years of age may be as high as 68 percent. (See 'Etiology' above and 'Epidemiology' above.)
●Patients with adult scoliosis often are asymptomatic. Symptomatic patients are usually ≥50 years of age and may present with back pain, postural imbalance with difficulties standing and walking, symptoms of spinal stenosis (neurogenic claudication, radiculopathy), neurologic deficits, and/or concerns about appearance (eg, decreased height, change in posture, asymmetry). (See 'Clinical presentation' above.)
●The objectives of the history (table 2) and examination (table 3) of the adult with scoliosis are to evaluate clinical findings of scoliosis (picture 1A) and determine the etiology (primary degenerative, progression of AIS, or secondary to another condition) and factors contributing to pain (for patients with pain), both of which affect management. (See 'Clinical evaluation' above.)
●The initial radiographic evaluation for scoliosis (standing posteroanterior [PA] and lateral views of the spine on a 36-inch digital cassette) may be ordered by the primary care clinician. Additional views and/or advanced imaging for patients with symptoms or more severe or progressive scoliosis is usually obtained by the spine specialist. (See 'Radiographic evaluation' above.)
●Adult scoliosis is a radiologic diagnosis: lateral (coronal) curvature with Cobb angle of >10° and complete closure of the iliac crest epiphysis (Risser 5 (figure 8)). The severity of scoliosis increases with increasing Cobb angle. (See 'Diagnosis' above.)
●Management of adult scoliosis is individualized according to etiology, severity of symptoms, and quality of life. Primary care management usually includes conservative treatments (eg, analgesic agents, referral for physiotherapeutic scoliosis-specific exercises). (See 'Primary care management' above.)
●Indications for referral to a spine specialist include persistent pain affecting quality of life despite conservative measures, symptoms (eg, neurogenic claudication; radicular pain; progressive weakness, clumsiness, or numbness; loss of bowel or bladder control). (See 'Indications for referral' above.)
●Specialist management of the adult patient with scoliosis includes serial monitoring of symptoms, quality of life, and curve magnitude and shared decision making regarding additional interventions, including surgery. (See 'Specialist management' above.)
