Congenital Muscular Torticollis

Torticollis, from the Latin words for “twisted neck,” is lateral neck flexion with contralateral head rotation (Figure 24-1). Although the majority of torticollis cases result from sternocleidomastoid muscle (SCM) shortening, other causes include neurologic conditions, cervical spine abnormalities, and vision or hearing deficits.

Figure 24-1 Torticollis.

Congenital muscular torticollis (CMT) occurs in 0.3% to 2% of newborns. Although the cause is unknown, intrauterine crowding or birth trauma may cause muscle damage. More than half of infants with CMT are firstborn or had a history of difficult delivery, including use of forceps or breech presentation. Magnetic resonance imaging (MRI) and surgical histopathology have demonstrated muscle atrophy and fibrosis similar to the vascular complications of compartment syndrome. Abnormal head positioning in CMT can cause plagiocephaly and facial asymmetry.

Evaluation of CMT should include a thorough birth history and description of presenting symptoms. The physical examination classically demonstrates an infant with the head tilted towards the side of SCM contraction with the chin pointed in toward the opposite shoulder (see Figure 24-1). A soft, nontender mass may be palpable in the body of the SCM. Visual tracking, hearing, and neurologic function should also be assessed to rule out nonmuscular causes. Patients should be evaluated for other associated conditions such as developmental dysplasia of the hip and referred for diagnostic imaging or surgical consultation as necessary.

Cervical spine radiographs can rule out osseous causes, including congenital spinal fusion (e.g., Klippel-Feil syndrome, unilateral atlantooccipital fusion), hemivertebrae, and rotational cervical instability. Ultrasonography, the diagnostic modality of choice, demonstrates a hyperechogenic muscle mass. Computed tomography (CT) and MRI can help exclude suspected neurologic or osseous etiologies of torticollis. However, these modalities may not be as sensitive as ultrasonography in diagnosing CMT, and exposure to radiation or sedation limits their role in routine evaluation of torticollis.

The majority of CMT resolves spontaneously or with regular physical therapy. If muscle shortening persists beyond 6 months of therapy or 12 months of life, orthopedic referral is necessary for surgical SCM lengthening. Although successful CMT therapy typically resolves the associated plagiocephaly and facial asymmetry, patients with residual symptoms may require referral for further evaluation and treatment.

Scoliosis

Scoliosis is a lateral curvature and rotation of the spine (Figure 24-2). Although most cases of scoliosis are idiopathic, it can also arise from congenital or neuromuscular disorders and is associated with various syndromes.

Figure 24-2 Scoliosis.

Idiopathic disease accounts for 80% of all scoliosis cases and is divided by age into infantile (0–3 years), juvenile (3–10 years), and adolescent (>10 years) groups. Infantile idiopathic scoliosis is rare and is unique in that it is more likely to occur in boys, have left-sided curvature, and spontaneously resolve. Juvenile idiopathic scoliosis is similar to the adolescent type; girls are predominantly affected, and the curvature is typically right-sided. Although juvenile idiopathic scoliosis does not occur during a period of rapid spine growth, it is more likely to be progressive than other types. Idiopathic scoliosis most commonly presents in adolescence (70%). Although the cause and pathogenesis of idiopathic scoliosis are largely unknown, there are multiple theories, including genetic factors; lack of melatonin; and abnormalities of platelets, nerves, and muscles.

The evaluation of idiopathic scoliosis should include a careful history and physical examination. Patients are screened for thoracolumbar asymmetry with an Adam’s forward bend test and scoliometer (see Figure 24-2). Examination should include comparison of the shoulders, scapulae, trunk, pelvis, and legs. Because idiopathic scoliosis is a diagnosis of exclusion, a careful assessment of neurologic function and signs of associated orthopedic disorders should be assessed. Congenital scoliosis should not be mistaken for infantile idiopathic scoliosis because the former is associated with other osseous and visceral anomalies. Definitive diagnosis and disease severity are determined by measuring the Cobb angle on a posteroanterior spinal radiograph, with any curvature more than 10 degrees being diagnostic. MRI is typically reserved for an atypical presentation or patients with focal neurologic findings.

Treatment of patients with idiopathic scoliosis depends on the age of onset and degree of curvature. Children with mild to moderate curves (<25 degrees), especially in the skeletally mature, can be observed clinically and with serial spinal radiographs. Physical therapy may also be used for minor disease. Patients with more severe curves, particularly younger children, may require bracing to minimize curve progression and prevent potential surgical correction. Unfortunately, the evidence for physical therapy and orthosis is equivocal, and their use is variable. Surgical correction is reserved for patients with severe curvatures (>45 degrees) or progressive disease that could compromise pulmonary or musculoskeletal function. Surgery can improve both the physical and psychological sequelae of idiopathic scoliosis. However, patients and their parents should be cautioned that although operative management can provide permanent structural correction, there are risks of surgical side effects or persistent symptoms.

Kyphosis

Normal sagittal, thoracic vertebral kyphosis is 20 to 45 degrees by the Cobb angle on a lateral radiograph. Larger angles are pathologic and result in a rounding of the upper back or “hunchback deformity.” The most common causes are postural kyphosis and Scheuermann’s disease (Figure 24-3). Rare causes include congenital kyphosis, infection, malignancy, and other neuromuscular or osseous disorders. Postural kyphosis is mostly seen in adolescent boys as a result of slouching. There is typically no back pain nor any radiographic abnormality. Scheuermann’s disease is an idiopathic osteochondritis that is a common cause of back pain in older children and adolescents. By definition, Scheuermann’s disease results in anterior wedging of at least 5 degrees in at least three adjacent vertebral bodies.

Figure 24-3 Scheuermann’s disease.

Treatment of kyphosis is based on the cause. Because there are no structural irregularities in postural kyphosis, positional exercises are sufficient. The natural history of Scheuermann’s disease is not well described, but physical therapy may improve symptoms. Orthotics may be useful for curves between 45 and 60 degrees, partial-angle correction, and pain relief. Operative repair is indicated for severe angles more than 75 degrees or curvature and pain refractory to bracing.

Spondylolysis and Spondylolisthesis

Spondylolysis is a fracture or other defect in the pars interarticularis of the vertebra. Spondylolisthesis is anterior vertebral slippage caused by spondylolysis or other vertebral trauma, degeneration, or pathology.

Spondylolysis is a sequela of lumbar hyperextension from sports-related repetitive impacts (e.g., football, gymnastics, wrestling) or congenital vertebral abnormalities (e.g., thoracolumbar kyphosis in Scheuermann’s disease). Patients may present with lumbar back pain, radiated buttock pain, or hamstring spasms. Spondylolysis is the most common cause of back pain in children after “idiopathic overuse.” Physical examination may be normal or may reveal ipsilateral lateral spine flexion, tenderness over the affected vertebra, or limited lumbar flexibility due to pain.

Oblique vertebral radiographs in an unaffected patient demonstrate a “Scottie dog” with the transverse process as the nose, the superior articular process as the ear, the spinous process and lamina as the body, and the inferior articular process as the front leg. In spondylolysis, the dog has a fracture line through the neck (Figure 24-4). In spondylolisthesis, the entire head of the dog is displaced, with or without spondylolysis, on a scale graded from I (<25% slip) to V (complete spondylolisthesis) (see Figure 24-4). Spondylolysis and spondylolisthesis most commonly occur at L5 on S1, which can be seen on anteroposterior and lateral radiographs. Radiographs are also useful in identifying the degree of slip and any associated anomalies. CT and MRI are helpful if there is an atypical presentation, if the degree of slip is severe, or for preoperative planning. A single photon emission CT scan can help distinguish an acute from a chronic pars interarticularis defect, with the latter typically requiring operative repair.

Figure 24-4 Spondylolysis and spondylolisthesis.

Medical treatment of patients with spondylolysis and spondylolisthesis includes rest, oral nonsteroidal antiinflammatory medications, and physical therapy. Rehabilitation should focus on reduction of the lumbar lordosis and hamstring stretching. Orthotics may be useful for more symptomatic spondylolysis patients to reduce lumbar lordosis. The majority of lesions heal with medical therapy alone. Surgery is usually reserved for chronic spondylolysis or severe (>grade III), symptomatic spondylolisthesis.

Vertebral Compression Fractures

Most compression fractures result from an axial or flexion load on the vertebral body, such as falls from a height, diving, and other sports injuries. Compression fractures represent the most common pediatric thoracic spine injury and are far more common in the thoracolumbar region than the cervical spine. Multiple fractures or an atypical mechanism should alert the provider to alternative diagnoses, including malignancy and nonaccidental trauma. In the absence of neurologic symptoms, treatment is usually conservative with rest, antiinflammatory medications, and use of orthotics. Many cervical injuries may require halo stabilization, and all unstable fractures require vertebral fusion.

Intervertebral Disk Herniation

Pediatric intervertebral disk herniation is rare but potentially disabling. Most cases are lumbar, typically L4–L5 or L5–S1, with posterolateral herniation. In contrast to adult disease, pediatric disk herniation is more likely to occur in the setting of trauma, with or without prior disk degeneration. Particularly, sports with axial load (e.g., gymnastics, diving) or torsion (e.g., wrestling, football, hockey) confer a higher herniation risk. Patients typically present with acute-onset lower back pain and associated radiculopathy, although the degree of pain varies widely. There are a number of acute and chronic conditions that may present similarly to disk herniation, including muscle strain, vertebral fracture, spondylolysis, spondylolisthesis, ankylosing spondylitis, slipped capital femoral epiphysis, diskitis, and intraspinal tumor. Schmorl’s nodes, a variant of disk herniation through the vertebral end plate instead of posterolaterally, should also be considered.

Examination commonly reveals limitation of movement and pain exacerbated by back flexion and straight-leg raises. There may also be a compensatory scoliosis that serves to alleviate nerve root pressure. Although spinal radiographs can show abnormalities consistent with herniation or other conditions, MRI is the study of choice. Nonoperative management is similar to that for other pediatric spine conditions and consists of rest, pain control, and physical therapy. Epidural steroid injections may provide additional pain relief. Unfortunately, pediatric disk histopathology demonstrates higher water content and elasticity compared with the condition in adults, which increases the likelihood of persistent herniation and need for surgical diskectomy in children. Operative repair is also indicated for debilitating neurologic deficits (e.g., severe motor impairment, incontinence), although these are rare. Long-term outcomes of disk herniation are generally favorable.

Future Directions

Disorders of the neck and spine are uncommon in children but are potentially debilitating. Although many disorders are benign and self-limiting, patients must be adequately assessed for comorbidities, persistent pathology, or symptoms that affect cosmesis and quality of life. Further study of treatment outcomes in a randomized, controlled fashion is paramount to evaluate the most minimally invasive and maximally effective therapies.