Scoliosis

Differential diagnosis with posture disorders

In the initial stages of development, scoliosis must be strictly differentiated from asymmetric posture. Asymmetric posture is an unstable deviation of the spine in the frontal plane. Its main difference from grade I scoliosis is that the curvature is of a functional (non-fixed) character. The patient is able to straighten their back independently through active muscle contraction, and X-ray examination shows no structural changes in the vertebral bodies.

True scoliosis, by contrast, is characterized by irreversible deformity. The curvature remains noticeable even when axial load is removed, and the progression of the disease is closely related to periods of intensive growth and puberty in the child.

Classification of scoliosis

Globally, the disease is divided into three large groups depending on the causes of onset:

1. Congenital scoliosis. Develops due to intrauterine skeletal anomalies (presence of hemivertebrae, supernumerary ribs, rib or spinous process synostoses). This also includes dysplastic scoliosis, which occurs against the background of spondylolysis, spina bifida occulta, or anomalies of the transitional lumbosacral region (sacralization, lumbarization), as well as hereditary (familial) forms.
2. Acquired scoliosis. Forms after birth under the influence of external or internal factors. It includes neurogenic forms (most often after poliomyelitis due to back and abdominal muscle imbalance, as well as in myopathies, neurofibromatosis), static (the result of lower limb shortening in joint pathologies, e.g., congenital hip dislocation), and rachitic (consequences of past rickets) forms.
3. Idiopathic scoliosis. The largest group, the etiology of which is not fully understood. Modern neurological, biomechanical, and electromyographic studies show that in its pathogenesis, this type is extremely close to dysplastic scoliosis.

Types of postural abnormalities and risk of scoliosis

Abnormalities in the sagittal plane (anteroposterior) directly affect the stability of the spine in the frontal plane (left-right). Orthopedists distinguish several types of abnormal posture:

• Flat back: physiological curves are sharply flattened, pelvic tilt angle is reduced, the chest is flattened, and the shoulder blades become winged. This is the most dangerous type of posture—it is the least resistant to lateral deviations, patients have the maximum predisposition to scoliosis, and require constant monitoring.
• Hunched back (round back): thoracic kyphosis is increased with flattened cervical and lumbar lordosis. The head is protruded forward, pelvic tilt angle is less than 40°. May be complicated by scoliotic deformity.
• Round-concave back: all physiological curves are increased, pelvic tilt angle exceeds 50°. Unlike a flat back, this type is much more stable and less frequently leads to frontal deviations.
• Kyphosis: pathological increase in the thoracic curve (apex at the level of Th7–Th8). A frequent cause in adolescence is Scheuermann's disease.

Role of contractures in the formation of defects

The search for the causes of postural defects (in the absence of systemic diseases) begins with identifying muscle contractures of large joints, which force the body to adopt compensatory postures:

• Shoulder joint: contracture of the pectoralis major muscles prevents raising the arms upward without artificially creating marked lumbar lordosis (tested against a wall).
• Hip joint: occurs due to weakness of the gluteal muscles and shortening of the iliofemoral ligament. Diagnosed by Thomas's sign (pressing one flexed leg to the abdomen in a lying position causes the second leg to rise).
• Hamstrings: shortening of the posterior thigh muscle group leads to the inability to reach the floor with hands while knees are straight. Contributes to the formation of persistent kyphosis in the lower thoracic region.

Principles of Diagnosis and Treatment

For a comprehensive assessment, V. Dega's special questionnaire of 31 tests, anthropometry, and functional tests are used (e.g., assessment of vital capacity, as deformations affect the topography of internal organs).

The basis of conservative treatment is the development of a "sense of correct posture" and elimination of the primary cause (selection of glasses for poor vision, orthopedic footwear for leg length discrepancy). The main method is corrective physical therapy (PT). Classes are held 3 times a week for 30–45 minutes, the exercise program is selected strictly individually depending on the cause of the curvature. The most important factor for success is the patient's conscious self-control.

Class and exam questions

What else to study on this topic

• Methodology for conducting V. Dega's 31 test questions for the diagnosis of postural disorders.
• Scheuermann's disease: etiology, clinical presentation, and radiological signs.
• Detailed biomechanics of the pelvic tilt angle and its effect on the spinal column.
• Technique for eliciting Thomas's sign in hip joint contracture.
• Assessment of vital capacity (VC) and the effect of scoliosis on internal organs.

Other Topics in "Orthopedics"

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