History of Spinal Orthotic Management

The first evidence of the use of spinal orthoses can be traced back to Galen (c.131 to 201 AD). Primitive orthotic devices were made of items that were readily available during this period (Figure 16-1). These items consisted of leather, whalebone, and tree bark. Spinal orthoses, although crude in their construction, have been recovered by archaeologists from the cliff dwellings of pre-Columbian Indians. The word orthosis is Greek and means “to make straight.”² Ambroise Paré (1510 to 1590) wrote about bracing and spinal supports, and Nicholas Andry (1658 to 1742) coined the term orthopaedia, pertaining to the straightening of children.⁴ Unstable areas such as fractures were often held in a corrected position with an orthosis, to allow for healing to occur. Normally fixed deformities were accommodated while flexible deformities were corrected. Orthopaedia was the predecessor to the field of orthotics.¹

FIGURE 16-1 Traction device, 1889.

In the past there were no organized training programs in the fabrication and application of orthoses, and an orthotist began as an apprentice, much like the village blacksmith. The training process for orthotists is now well defined and rigorous, with a certification process in the United States. Orthotists are now required to have extensive knowledge of pathologies and the proper fabrication and use of orthotic devices. Technology has revamped the field of orthotics, with new stronger and lighter materials. Although materials available for orthotic construction have changed, the types of pathologic conditions treated have remained virtually constant for years.

The primary goal of modern orthoses is to aid a weakened muscle group or correct a deformed body part. The orthosis can protect a body part to prevent further injury, or can correct the position (immediate term or long-term) of the body part. The same approach is true for spinal orthoses. The clinician’s priority should be to determine which spinal motion to control. Good clinical outcomes can be maximized through the proper selection, use, and application of the orthosis. (See Chapters 14 and 15 for further information on orthoses.)

Terminology

Terminology is currently often misused in the field of orthotics. Definitions of some terms commonly used in the field are listed below:

Acronyms are frequently used to describe orthoses. They are named for the parts of the body where they are located and have some influence on the motion in that body region. Some examples of spinal orthoses follow:

Prefabricated Versus Custom Orthoses

The availability of prefabricated orthoses today presents the rehabilitation team with a variety of choices and some challenges. Many of the prefabricated orthoses come in various sizes and can be fitted to patients often with little or no adjustment. While this can be a benefit to the patient and the team in terms of time, care should be taken to ensure that the design and function of these orthoses are appropriate for the patient’s condition and not used purely for convenience. Custom orthoses, in most cases, provide a more comfortable fit with a higher degree of control, and can be designed to accommodate a patient’s unique body shape or deformities. Recognition of the time needed to fabricate the orthosis, the experience of the fabricator, the patient’s specific condition, and the expectations of the patient are all factors that should be considered when ordering a custom orthosis.

Orthotic Prescription

The orthotic prescription allows for improved communication between clinicians, and it serves as a justification of the funding of the orthosis. Insurer-requested justification for the orthosis is becoming more common as medical costs have increased. Insurer approval of the prescription is more likely if the orthosis clearly increases independence or helps prevent detrimental outcomes, such as a fall. The prescribing rehabilitation physician is responsible for the final order. The prescription should be accurate and descriptive, but not so descriptive as to limit the orthotic team’s independent ability to maximize functionality and patient acceptance.

Prescriptions should include the following items:

Prescriptions should include a justification, such as the correction of alignment, to decrease pain, or to improve function. Brand names and eponyms for the orthosis should be avoided. Established acronyms are acceptable (e.g., TLSO). Detailed descriptions of the orthosis, the joints involved, and the functional goals are important. For a nonarticulated orthosis the fixed angle should be indicated. For an orthosis with a moveable joint, the range of motion desired, end limitations of range, and assistance (or resistance) through the range should be specified. Before the prescription is finalized, input from the patient, physician, therapist, and orthotist is needed. It is especially important for physicians to review the use, or lack of use, of past orthoses, because this will help guide their new prescription. If a patient discontinues the use of an orthosis prematurely, the reason why this occurred should be investigated by the provider before additional resources are expended. Knowledge of the patient’s medical condition(s) is essential for a number of reasons. For example, the condition might be progressive, with further expected functional loss. On the other hand, the condition might be expected to improve partially or completely in the future.

Spinal Anatomy

The vertebral column is composed of 33 vertebrae, including 7 cervical, 12 thoracic, 5 lumbar, 5 inferiorly fused vertebrae that form the sacrum, and 5 coccygeal. The spinal column not only bears the weight of the body, but it also allows motion between body parts and serves to protect the spinal cord from injury. Before birth, there is a single C-shaped concave curve anteriorly. At birth, infants have only a small angle at the lumbosacral junction. As a child learns to stand and walk, lordotic curves develop in the cervical and lumbar region (age 2 years). These changes can be attributed to the increase in weight-bearing and differences in the depth of the anterior and posterior regions of the vertebrae and disks.^28,32

The cervical vertebrae are small and quadrangular, except for C1 and C2, which have some unique features. The cervical articular processes face upward and backward, or downward and forward. The orientation of the facet joints is important to note, as it relates to limitations of movement of the vertebral column. The thoracic vertebrae have heart-shaped bodies. The thoracic vertebrae are intermittent in size but increase in size caudally. This is related to the increased weight-bearing requirements. The dorsal length of the thoracic vertebrae is approximately 2 mm more than the ventral side, which could account for the thoracic curve. Their superior articular processes face backward and outward, and the inferior ones face forward and inward. The lumbar vertebrae have a large, kidney-shaped body. Their upper articular processes face medially and slightly posteriorly, and the lower ones face laterally and slightly anteriorly. The five sacral vertebrae are fused in a solid mass and do not contain intervertebral disks. The sacral bony structure acts as a keystone, and weight-bearing increases the forces that maintain the sacrum as an integral part of the spinal pelvic complex.

The spine is composed of more than vertebral bodies. The intervertebral disk is composed of a nucleus pulposus, annulus fibrosus, and cartilaginous end plate. Disks make up approximately one third of the entire height of the vertebral column. The nucleus contains a matrix of collagen fibers, mucoprotein, and mucopolysaccharides. They have hydrophilic properties, with a very high water content (90%) that decreases with age.²⁷ The nucleus is centrally located in the cervical thoracic spine, but more posteriorly located in the lumbar spine. The annulus fibrosus has bands of fibrous laminated tissue in concentric directions, and the vertebral end plate is composed of hyaline cartilage.

Normal Spine Biomechanics

Movement of the vertebral column occurs as a combination of small movements between vertebrae. The mobility occurs between the cartilaginous joints at the vertebral bodies and between the articular facets on the vertebral arches. Range of motion is determined by muscle location, tendon insertion, ligamentous limitations, and bony prominences. In the cervical region, axial rotation occurs at the specialized atlantoaxial joint. At the lower cervical levels, flexion, extension, and lateral flexion occur freely. In these areas, however, the articular processes, which face anteriorly or posteriorly, limit rotation. In the thoracic region, movement in all planes is possible, although to a lesser degree. In the lumbar region, flexion, extension, and lateral flexion occur, but rotation is limited because of the inwardly facing articular facets.¹¹ An understanding of the three-column concept of spine stability/instability is helpful to ensure that the proper orthosis is prescribed. The anterior column consists of the anterior longitudinal ligament, annulus fibrosus, and the anterior half of the vertebral body. The middle column consists of the posterior longitudinal ligament, annulus fibrosus and the posterior half of the vertebral body. The posterior column consists of the interspinous and supraspinous ligaments, the facet joints, lamina, pedicles, and the spinous processes. The loss of normal spinal anatomy can affect the stability of the spine.

Spine motion can be classified with reference to the horizontal, frontal, and sagittal planes. Spinal motion can shift the center of gravity, which is normally located approximately 2 to 3 cm anterior to the S1 vertebral body. White and Panjabi³³ provided a summary of the current literature, revealing motion in flexion and extension, laterally, and axially (Figure 16-2). In the cervical spine, extension occurs predominantly at the occipital C1 junction. Lateral bending occurs mainly at the C3–C4 and C4–C5 levels. Axial rotation occurs mostly at the C1–C2 levels. In the thoracic spine, flexion and extension occur primarily at the T11–T12 and T12–L1 levels. Lateral bending is fairly evenly distributed throughout the thoracic levels. Axial rotation occurs mostly at the T1–T2 level, with a gradual decrease toward the lumbar spine. The thoracic spine is the least mobile because of the restrictive nature of the rib cage. In the lumbar spinal segment, movement in the sagittal plane occurs more at the distal segment, with lateral bending predominantly at the L3–L4 level. There is insignificant axial rotation in the lumbar spinal segment.

FIGURE 16-2 Representative values for range of motion of the cervical, thoracic, and lumbar spine as summarized from the literature.

(Data from White AA, Panjabi MM: The lumbar spine. In: White AA, Panjabi MM, editors: Clinical biomechanics of the spine, ed 2, Philadelphia, 1990, Lippincott.)

Knowledge of the normal spinal range of motion helps in understanding how the various cervical orthoses can limit that range (Table 16-1). Soft collars provide very little restriction in any plane. The Philadelphia-type collar mostly limits flexion and extension. The four-poster brace and Yale orthosis have better restriction, especially with flexion-extension and rotation. The halo brace and Minerva body jacket have the most restriction in all planes of motion.

An interesting phenomenon related to movement in the spine occurs during motion. If the movement along one axis is consistently associated with movement around another axis, coupling is occurring. For example, if a patient performs left lateral movement (frontal plane) motion, the middle and lower cervical and upper thoracic spine rotate to the left in the axial plane (Figure 16-3). This causes the spinous processes (posterior side of the body) to move to the right. In the lower thoracic spinal segment, left lateral movement in the frontal plane can cause rotation in the axial plane, with the spinal processes moving in either direction. The lumbar area has a contradictory movement pattern when compared with the cervical spine. With left lateral bending of the lumbar spine, the spinous processes move to the left. A three-dimensional perspective is important to maintain during examination. Patients with scoliosis and patients who undergo radiologic testing would benefit from an evaluation for the normal coupling patterns noted.

FIGURE 16-3 Regional coupling patterns. Summary of the coupling of lateral bending and axial rotation in various subdivisions of the spine. In the middle and lower cervical spine as well as the upper thoracic spine, the same coupling pattern exists. In the middle and lower thoracic spine, the axial rotation, which is coupled with lateral bending, can be in either direction. In the lumbar spine, the spinous processes go to the left with left lateral bending.

(Redrawn from White AA, Panjabi MM: the lumbar spine. In: White AA, Panjabi MM, editors: Clinical biomechanics of the spine, ed 2, Philadelphia, 1990, Lippincott.)

Nachemson^21–23 performed the classic studies on normal adults that measured intradiskal pressures during a variety of activities and positions. Standing pressure was referenced as 100 in the lumbar disk. Lowest pressure measurements were noted in the supine position, with progressively higher pressures in the following positions: side lying, standing, sitting, standing with hip flexion, sitting with forward flexion, standing with forward flexion, and lifting a load while sitting with forward flexion.²⁴

Description of Orthoses

Head Cervicothoracic Orthoses

Type: Halo Orthosis

Biomechanics

The halo orthosis (Figure 16-4) provides flexion, extension, and rotational control of the cervical region. Pressure systems are used for control of motion, as well as to provide slight distraction for immobilization of the cervical spine.

FIGURE 16-4 Halo orthosis.

Design and Fabrication

The halo orthosis consists of prefabricated components such as a halo ring, pins, uprights (or superstructure) and vest. The halo ring is fixed to the outer table of the skull bones with generally four or more metal pins. On the typical adult patient the pins are optimally placed under local anesthesia, less than 1 inch above the lateral third of each eyebrow (to avoid the sinuses) and less than 1 inch above and just posterior to the top of each ear. Upright bars or superstructure connects the ring to a rigid plastic thoracic vest, which is lined with lamb’s wool.

The halo is adjustable for flexion, extension, anterior and posterior translation, rotation, and distraction. The vest wraps around the thoracic region of the spine and is fastened laterally, usually by buckles. The design is used to effectively immobilize the cervical spine.

This orthosis provides maximum restriction in motion of all the cervical orthoses. It is the most stable orthosis, especially in the superior cervical spine segment. A halo is used for approximately 3 months (10 to 12 weeks) to ensure healing of a fracture or of a spinal fusion. Usually a cervical collar is indicated after the halo is removed, because the muscles and ligaments supporting the head become weak after disuse. All pins on the halo ring should be checked to ensure tightness 24 to 48 hours after application, and retorqued if necessary.

Indications

The halo is generally used for unstable cervical fractures or postoperative management.

Contraindications

Contraindications are stable fractures or when other, less invasive management could be used. Patients with an extremely soft skull might not tolerate the pin placement.

Special Considerations

Skull density determines halo pin placement as well as the number of halo pins to be used. While four pins are used on average, more can be necessary in soft skulls (e.g., osteoporotic, fractured, or in an infant) to distribute the force over a broader area of the skull.

Cervical Orthoses

Type: Philadelphia or Miami J

Biomechanics

The Philadelphia (Figure 16-5) and Miami J (Figure 16-6) orthoses provide some control of flexion, extension, and lateral bending, and minimal rotational control of the cervical region. Pressure systems are used for control of motion, as well as to provide slight distraction for immobilization of the cervical spine. Circumferential pressure is also intended to provide warmth and as a kinesthetic reminder for the patient.

FIGURE 16-5 Philadelphia orthosis.

FIGURE 16-6 Miami J orthosis.

Design and Fabrication

These orthoses are prefabricated, consisting of one or two pieces that are usually attached with Velcro straps. Two-piece designs have an anterior and posterior section. The anterior section supports the mandible and rests on the superior edge of the sternum. The posterior aspect of the collar supports the head at the occipital level.

Indications

They are used primarily for cervical sprains, strains, or stable fractures. They can also be used for protection and to limit mobility after surgery to allow healing.

Contraindications

These orthoses are not indicated for unstable fractures.

Cervicothoracic Orthoses

Type: Sternal Occipital Mandibular Immobilizer

Biomechanics

The sternal occipital mandibular immobilizer (SOMI; Figure 16-7) provides control of flexion, extension, lateral bending, and rotation of the cervical spine. Pressure systems are used for control of motion, as well as to provide slight distraction for immobilization of the spine. A benefit of the SOMI orthosis is that it can be donned while the patient is in the supine position. The SOMI is a good choice for patients who are restricted to bed, because there are no posterior rods to interfere with comfort of the patient. A headband can be added so that the chin piece can be removed. This maintains stability but improves accessibility for daily hygiene and eating.

FIGURE 16-7 Sternal occipital mandibular immobilizer.

Design and Fabrication

The SOMI is prefabricated, consisting of a cervical portion with removable chin piece and bars that curve over the shoulders. Also used are posts that fixate the cervical portion to the sternal portion of the orthosis. The anterior section supports the mandible and rests on the superior edge of the sternum, with the inferior anterior edge terminating at the level of the xiphoid. The posterior aspect of the orthosis supports the head at the occipital level.

Indications

The SOMI is used primarily for cervical sprains, strains, or stable fractures with intact ligaments. It can also be used for protection and to limit mobility during the healing process in the postoperative patient.

Contraindications

This orthosis is not indicated for unstable fractures with ligament instability.

Yale

The Yale orthosis consists of chin and occipital pieces that extend higher on the skull in the posterior region; this increases comfort. The Yale orthosis is a modified Philadelphia collar with a thoracic extension. The extension consists of fiberglass that extends both anteriorly and posteriorly, and has thoracic straps that hold the sections together. The thoracic extension to the orthosis helps to stabilize injuries at the vertebral levels of C6–T2.

Four-Poster

The four-poster is a rigid cervical orthosis with anterior and posterior sections consisting of pads that lie on the chest and are connected by leather straps. The struts on the anterior and posterior sections are adjustable in height. Straps are used to connect the occipital and mandibular support pieces by way of the over-the-shoulder method.

Also note that some cervical orthoses can also incorporate a sternal extension addition, which converts them from a cervical orthosis to a cervicothoracic orthosis (e.g., Aspen, Philadelphia, Miami J).

Thoracolumbosacral Orthoses

Type: Thoracolumbosacral Orthosis (Prefabricated)

Biomechanics

The thoracolumbosacral orthosis (TLSO; prefabricated) (Figure 16-8) provides control of flexion, extension, lateral bending, and rotation using three-point pressure systems and circumferential compression.

FIGURE 16-8 Thoracolumbosacral orthosis (prefabricated).

Design and Fabrication

This orthosis can be designed in modular forms, with anterior and posterior sections connected by padded lateral panels and fastened with Velcro straps or pulley systems. Many of these are covered in breathable fabric and have a variety of different shapes and options, such as sternal pads or shoulder straps.

Indications

This orthosis can be used for treatment of traumatic or pathologic spinal fractures in the mid to lower thoracic region or lumbar region.

Contraindications

These include a body habitus that is obese with a pendulous abdomen, excessive lordosis, or a need for increased lateral stability.

Special Considerations

Cost is reduced in some models because of the mass production of prefabricated modules. The use of breathable material can increase compliance with wearing.

Type: Thoracolumbosacral Orthosis (Custom-Fabricated Body Jacket)

Biomechanics

The body jacket (Figure 16-9) provides control of flexion, extension, lateral bending, and rotation. It uses three-point pressure systems and circumferential compression.

FIGURE 16-9 Thoracolumbosacral orthosis (custom-fabricated body jacket).

Design and Fabrication

It is molded to fit the patient and designed for patient needs. Anterior trim lines are usually located inferior to the sternal notch and superior to the pubic symphysis. The posterior trim lines have a superior border at the spine of the scapula, and an inferior border at the level of the coccyx. These trim lines are adjusted during fitting to allow patients to sit comfortably and to use their arms as much as possible without compromising the function of the orthosis.

Indications

This orthosis can be used for treatment of traumatic or pathologic spinal fractures in the mid to lower thoracic region or lumbar region. Most are used for postsurgical management of fractures, such as compression, Chance, or burst. The brace is also used after surgical correction spondylolisthesis, scoliosis, spinal stenosis, herniated disks, and disk infections.

Contraindications

Contraindications include application of the orthosis over a chest tube, colostomy, or large dressings.

Special Considerations

Care must be taken to ensure that contact is maximized to decrease the pressure in any one area. Trim-line changes must be made in small increments to prevent loss of control in terms of both leverage and tissue control. Ventilating holes are often made to improve airflow. Other factors to be considered when making the design include patients who might attempt to remove the orthosis when out of bed. The orthosis can be made with a posterior opening to reduce the risk.

Type: Cruciform Anterior Spinal Hyperextension Thoracolumbosacral Orthosis

Biomechanics

The cruciform anterior spinal hyperextension (CASH) TLSO (Figure 16-10) provides flexion control for the lower thoracic and lumbar regions. It accomplishes this by way of a three-point pressure system. The system consists of posteriorly directed forces through a sternal and suprapubic pad, and an anteriorly directed force applied through a thoracolumbar pad attached to a strap that extends to the horizontal anterior bar.

FIGURE 16-10 Cruciform anterior spinal hyperextension thoracolumbosacral orthosis.

Design and Fabrication

The CASH is prefabricated, consisting of an anterior frame in the form of a cross, from which pads are attached laterally on a horizontal bar and at the sternal and suprapubic areas. A thoracolumbar pad is attached to a strap that extends to the lateral sections of the horizontal bar and adjusts the tension on the body. When properly fitted, the sternal pad is one-half inch below the sternal notch, and the suprapubic pad is one-half inch above the symphysis pubis.

Indications

This orthosis is used primarily for the treatment of mild compression fracture of the lower thoracic and thoracolumbar regions.

Contraindications

The CASH is not indicated for unstable fractures or burst fractures.

Special Considerations

Excessive pressure on the sternum can result in poor compliance with wearing schedule. Subclavicular pads may be added to help distribute this pressure.

Type: Jewett Hyperextension Thoracolumbosacral Orthosis

Biomechanics

The Jewett hyperextension TLSO (Figure 16-11) provides flexion control for the lower thoracic and lumbar regions. This is done with a three-point pressure system consisting of posteriorly directed forces through a sternal and suprapubic pad, and an anteriorly directed force applied through a thoracolumbar pad attached to a strap that extends to the lateral uprights.

FIGURE 16-11 Jewett hyperextension thoracolumbosacral orthosis.

Design and Fabrication

It is prefabricated, consisting of an anterior and lateral frame to which pads are attached laterally on and at the sternal and suprapubic areas. A thoracolumbar pad is attached to a strap that extends to the lateral uprights and adjusts the tension on the body. When properly fit, the sternal pad will be one-half inch below the sternal notch, and the suprapubic pad will be one-half inch above the symphysis pubis.

Indications

The Jewett hyperextension TLSO is used primarily for the treatment of mild compression fractures of the lower thoracic and thoracolumbar regions. The Jewett has more lateral support than the CASH.

Contraindications

It is not indicated for unstable fractures or burst fractures.

Special Considerations

Excessive pressure on the sternum might result in poor compliance with wearing schedule. Subclavicular pads can be added to help distribute this pressure.

Type: Taylor and Knight-Taylor

Biomechanics

The Taylor and Knight-Taylor orthoses provide control of flexion, extension, and a minimal axial rotation via the three-point pressure systems for each direction of motion. For example, flexion is controlled by the posteriorly directed forces applied through the axillary straps and the abdominal apron, and an anteriorly directed force through the paraspinal uprights.

Design and Fabrication

The design of the Taylor consists of a posterior pelvic band extending past the midsagittal plane and across the sacral area. Two paraspinal uprights extend to the spine of the scapula. An apron front extends from the xiphoid to just above the pubic area. There are straps extending from the top of the posterior uprights around the posterior axillary to the scapular bar and forward to the apron. Other straps extend from the paraspinal uprights to the apron.

The Knight-Taylor has an additional thoracic band that extends from the uprights just below the inferior angle of the scapula to the midsagittal plane, and a lateral upright on each side that connects the pelvic band and the thoracic band. These bands provide additional lateral support and motion control to the trunk.

Indications

These orthoses have been used for years for postsurgical support of traumatic fractures, spondylolisthesis, scoliosis, spinal stenosis, herniated disks, and disk infections. However, clinicians typically now prefer the custom-molded TLSO body jackets, because better control of position is obtained.

Contraindications

Contraindications are unstable fractures that require maximum stabilization.

Special Considerations

Pressure per square inch is higher because of the width of the bands and uprights.

Lumbosacral Orthoses

Type: Lumbosacral Corset

Biomechanics

The lumbosacral corset (Figure 16-12) provides anterior and lateral trunk containment, and assists in the elevation of intraabdominal pressure. Restriction of flexion and extension can be achieved with the addition of steel stays posteriorly.

FIGURE 16-12 Lumbosacral corset.

Design and Fabrication

This orthosis is usually made from cloth that wraps around the torso and hips. Adjustments are done with laces on the sides, back, or front. Closure can be with hook and loop (Velcro) or hook and eye fasteners or snaps. Many different styles are available in prefabricated sizes, usually in 2-inch increments, and are designed to fit the body circumference at the level of the hips. The orthosis can be adjusted for body type and proper fit by taking tucks in the cloth, as needed. Steel stays must be contoured to the body shape to encourage a reduction of lordosis or to accommodate a deformity. Custom corsets can be fabricated based on careful measurements of the individual patient.

Indications

This orthosis is the most frequently prescribed support for patients with low back pain.²⁹ It has been used for herniated disks and lumbar muscle strain, and to control gross trunk motion for pain control after single-column compression fractures with one-third or less anterior height loss.³⁴

Contraindications

The orthosis should not be used for unstable fractures, as well as fractures or conditions above the lower lumbar region.

Special Considerations

Long-term use of a lumbosacral corset can cause an increase in motion in the segments above or below the area controlled by the orthosis.²⁶ Muscle atrophy can also potentially occur after long-term use, causing an increased risk of reinjury. Patients can also develop a psychologic dependence on the support after injury.¹⁵

Type: Lumbosacral Chair-Back Orthoses

Biomechanics

This brace (Figure 16-13) provides limitation of flexion, extension, and lateral flexion. It also provides elevation of intraabdominal pressure.

FIGURE 16-13 Lumbosacral orthosis chair-back brace.

Design and Fabrication

This orthosis has a pelvic band that lies posteriorly and extends laterally to just anterior to the midsagittal line. Laterally the ends fall midway between the iliac crest and the greater trochanter. The superior edge of the thoracic band is at the level of T9–T10 or just distal to the inferior angle of the scapulae. The pelvic and thoracic bands are connected by two paraspinal uprights posteriorly and a lateral upright on each side at the midsagittal line. Orthoses can be fabricated from a traditional aluminum frame covered in leather, or thermoplastic material molded into the same shape. Straps are connected in a variety of ways to the frame, providing attachment to the anterior apron front.

Indications

This brace is often used for lower lumbar pathologic conditions, including degenerative disk disease, herniated disk, spondylolisthesis, and mechanical low back pain, and for postsurgical supports for lumbar laminectomies, fusions, or diskectomies.²⁵

Contraindications

These are unstable fractures, or conditions in the upper lumbar or thoracic area.

Special Considerations

Adequate clearance of the paraspinal uprights is required to allow for some reduction of lumbar lordosis when the anterior apron is tightened and while sitting. Clearance on the lateral uprights over the iliac crests is also an area to be monitored.

Scoliosis

Idiopathic (infantile, juvenile, adolescent), congenital, and neuromuscular scoliosis have different etiologies, treatment approaches, and outcomes. Idiopathic scoliosis is the most common form.³⁰ Idiopathic infantile scoliosis is typically described from birth to 3 years of age, juvenile is from 4 years until the onset of puberty, and the adolescent type from puberty to closure of the facets.

With idiopathic scoliosis the evaluation should reveal no anomalous vertebrae, spinal tumors, or other neurologic abnormalities. Most cases remain stable for a long period and progress late in life when osteoporosis and degenerative spinal conditions normally have their onset. Progressive curves need to be treated, but there is not adequate evidence that scoliosis can be treated by electrical stimulation, nutritional supplementation, exercise, or chiropractic treatment. There is evidence to indicate that an orthosis can slow the progression of idiopathic scoliosis, and it is therefore the nonoperative treatment of choice.

Juvenile idiopathic scoliosis is more likely to be associated with adult cor pulmonale and death. Treatment should begin when curves reach approximately 25 degrees. Because thoracic curves predominate, the Milwaukee brace might be more effective than the TLSO. The Milwaukee (CTLSO) brace has a pelvic section with close contact with the iliac crest and lumbar spine. Three uprights (one anterior and two posterior) typically connect to a neck ring, throat mold and occipital pad. The Boston brace is a TLSO that uses symmetric standardized modules, eliminating the need for casting. It extends from below the breast to the beginning of the pelvic area and below the scapulae posteriorly. It maintains flexion of the lumbar area by increasing pressure on the abdomen, and is a popular TLSO brace.

Adolescent idiopathic scoliosis is the most common type for which an orthosis is indicated, usually for curves between 25 and 45 degrees. Curves with an apex at T9 or lower can be managed with a TLSO. Curves with a higher apex require a Milwaukee brace. Single lumbar curves are treated with a lumbosacral orthosis.⁸

Congenital scoliosis is secondary to a vertebral anomaly that is present at birth. Failure of part of the vertebrae to form (e.g., hemivertebrae) or failure of the vertebrae to properly segment (block vertebrae), or a combination of both, can occur. Congenital scoliosis is associated with abnormal development in the embryo, and associated developmental abnormalities in other organ systems should be considered, especially in the renal, urinary, and cardiac systems.¹⁹

Neuromuscular diseases are also associated with scoliosis. The prevalence of scoliosis in this population is much higher than with idiopathic scoliosis, from 25% to 100%. In pediatric patients with a spinal cord injury, almost 100% have scoliosis. In general, there is a significant chance of progression in the presence of severe neurologic disease. In adults, however, scoliosis curvatures tend to be relatively benign and of the C-type appearance, and are less likely to progress to the extent that they cause clinical cardiopulmonary problems. Progression of the curve can occur in adulthood, which is typical for scoliosis in general. Spasticity or flaccidity can be present, depending on whether there is upper versus lower motor neuron involvement. Multisystem involvement is more common in this group because these diseases are not isolated to the spinal column. Consideration should also be made for the presence of contractures, hip dislocations, sensory abnormalities, mental retardation, and pressure ulcers.¹⁴

Scoliosis can continue to progress despite the proper use of an orthosis, and in these cases appropriate surgical referrals should be made. An important factor to consider before surgery is the pulmonary function in a patient with neuromuscular disease. Before surgery is considered, the forced vital capacity and forced expiratory volume in 1 second should be at least 40% of that predicted for the patient’s age. Fusions are delayed as long as possible in an attempt to achieve maximal spinal growth (>10 years of age). Declining pulmonary function, however, is a consideration for performing surgery earlier.²⁰

Duval-Beaupere⁷ followed the long-term progression of idiopathic scoliosis and noted that curve progression accelerated during growth spurts. He noted that the younger the child, the higher the risk of curve progression, because of a greater amount of growth that remained. It has also been shown that the greater the curve, the more likely the curve would increase.¹⁴ Curves measured from 5 to 29 degrees, and the curves from 20 to 29 degrees progressed in almost 100% of the patients. Approximately 50% of the curves from 5 to 19 degrees appeared to progress.

Curve progression has been explained using Euler’s theory of elastic buckling of a slender column.³¹ Axial compressive forces evidently cause a column to buckle. This is associated with height growth and weight gain, especially increased upper limb weight during growth spurts. An increase in height and weight commonly occur together and might synergistically promote curve progression. It has been noted by these authors and others that the condition of a child with a large curve is more likely to progress than that of a child with a small curve.

The timing for surgery in a child with scoliosis is controversial. A child with a curve greater than 45 degrees, a child who is still growing, or a child who cannot or does not wear a brace are at a greater risk of curve progression and may be considered for surgery.

Type: Thoracolumbosacral Low-Profile Scoliosis Orthoses

Boston Brace, Miami Orthosis, Wilmington Brace

Biomechanics

The TLSO low-profile scoliosis orthoses (Figure 16-14) provide dynamic action using three principles (end-point control, transverse loading, and curve correction) to prevent curve progression and to stabilize the spine.

FIGURE 16-14 Thoracolumbosacral low-profile scoliosis orthosis.

Design and Fabrication

The use of orthoses or other devices to halt the curve progression of structural scoliosis has been reported as far back as Hippocrates.¹⁸ Many different types of orthoses have been described in the literature. The one that stands out as being the most successful is the Milwaukee orthosis, which was described previously.

The effective nonoperative treatment of idiopathic scoliosis using a low-profile TLSO has been demonstrated over the past 30 years. The most common of these orthoses is the Boston brace, introduced by Hall and Miller¹⁰ in 1975.³ This system is available in prefabricated modules that are available in 30 sizes and can be ordered by measurement; they are then custom-fit to the patient. Modules can be used to fit approximately 85% of patients. Six of these sizes will fit approximately 60% of patients requiring an orthosis.⁹ The orthosis can also be custom-fabricated from a mold of the patient’s body. Trim lines are established based on the patient’s curve; they are designed to provide pressure in specified areas to maximize corrective forces, and at the same time be less visible under the patient’s clothing.

Indications

This orthosis is indicated in patients with an immature skeleton and documented progression of a thoracic or thoracolumbar idiopathic scoliosis that measures 25 to 35 degrees (measured by the Cobb method) and has an apex of T7 or lower.⁵

Contraindications

The orthosis is contraindicated in patients with curves that measure greater than 40 degrees and who are skeletally immature, or with curves in excess of 50 degrees after the end of growth. Both of these types of patients are typically candidates for surgery.⁶

Special Considerations

Idiopathic scoliosis occurs mostly in adolescent females. Treatment regimens, both nonoperative and operative, are major events for the patients and their families. To be successful, the treatment team must be sensitive, supportive, honest, and communicate accurate information to patients and their families.

The effectiveness of any orthotic system depends on compliance with the wearing schedule. Most patients should wear the orthosis 23 to 24 hours per day for it to be effective. Some physicians allow time out of the orthosis to participate in athletic activities or swimming and some special occasions, and this seems to improve acceptance and compliance.

Future Technology

Computer-Aided Design and Computer-Aided Manufacturing

Technology is available to help the practitioner improve efficiency in design and fabrication, as well as reducing the invasiveness of orthotic measurement of the patients. The development of computer-aided design (CAD) and computer-aided manufacturing (CAM) has allowed the fabrication of orthoses today in less time than it took only a few years ago. The BioScanner Biosculptor is one of the CAD-CAM systems available (Figure 16-15). (BioScanner biosculptor information is available online at http://www.biosculptor.com.) It combines CAD, laser scanning, three-dimensional imagery, and motion-tracking technology to design orthotic and prosthetic devices. This is an alternative to traditional casting methods. The body part involved is scanned via a handheld scanning wand, which uses a motion-tracking device embedded in the scanner. The wand is passed over the body part. A three-dimensional image of the body part is transmitted to the computer, and the software interprets the data. Any portion of the body can be directly scanned. There is no size limitation. A miniature transmitter is placed on the body to accommodate for any movement. The BioScanner is able to image negative and positive models, allowing the clinician to use the clinical techniques required for each patient. With scan-through-glass technology that the company provides for use with its scanner, the clinician can position the body horizontally for a TLSO. The BioScanner automatically corrects the refraction. The precision of the BioScanner captures shapes to an accuracy of 0.178 mm. It provides the clinician with detailed and accurate three-dimensional measurements. Patients can be scanned for spinal jackets without movement from supine to prone positions. An option in the computer software allows one hemisphere to be scanned, and then the computer develops the other hemisphere to form a complete image. The older plaster cast methods are becoming obsolete because of the following advantages of the scanning system: it is not messy, can be done quickly, minimizes pain for the patient, and is more accurate. Modifications to these scanned computerized models can then be made before fabrication of the device begins.

FIGURE 16-15 BioScanner handheld laser scanner system.

Accuracy of measurement gives detailed surface information often lost with a cast or mechanical digitizer. The patient’s scan is maintained in the computer database, allowing for rapid refitting and medical justification of new devices by showing volumetric changes.

Bone Stimulation

The CMF SpinaLogic bone growth stimulator is a portable, battery-powered, microcontrolled, noninvasive bone growth stimulator indicated for adjunct electromagnetic treatment to primary lumbar spinal fusion surgery for one or two levels (Figure 16-16). (Information about the CMF SpinaLogic is available at the website of DJO, Inc: http://www.djortho.com.)

FIGURE 16-16 CMF SpinaLogic bone stimulator.

There are different bone stimulators on the market that are in use today. Some are used in conjunction with spinal orthoses and do not interfere with the control that the orthosis provides or the treatment protocol set by the physician. Some of the benefits of these bone stimulators are as follows: (1) they are lightweight, comfortable, and easy to use; (2) they can be used after an anterior or posterior approach in surgery; and (3) they are noninvasive.

This treatment has been shown to give a 21% point increase in healing over those who did not use the stimulator. It also helps the body’s own healing process to begin working.

Summary

The proper prescription, construction, and fitting of a spinal orthosis is a complicated process. It is important that a complete, clear, and agreed plan of care is constructed. Success is likely to be limited if there is no agreement or understanding of the process and goals. The typical orthotic team in the United States includes the patient, orthotist, rehabilitation physician, and therapist. Experienced and knowledgeable providers working in a team approach provide the maximum likelihood that the orthosis will contribute to the overall therapeutic goals for the patient.