UPPER BACK AND THORACIC SPINE TRAUMA
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Upper-thoracic spasms and trigger points are the most common of the milder complaints heard in a chiropractic office. Typical posttraumatic injuries of the posterior thorax involve the large posterior musculature, thoracic spine, spinocostal joints, and tissues supporting and mobilizing the scapula (especially the rhomboids).
Severe biomechanical lesions of the thoracic spine are seen less frequently than those of the cervical or lumbar spine. But when they occur, they may be serious if related to disc protrusion or a dynamic facet defect. Shoulder girdle, rib cage, spinal cord, cerebrospinal fluid flow, and autonomic visceral problems originating in the thoracic spine are far from being uncommon. Common biomechanical concerns are the prevention of thoracic hyperkyphosis, flattening, or twisting, as each can contribute to both local and distal, acute and chronic health-threatening manifestations. Compression fractures vary from a single slight irregularity in the anterior or lateral margins of the vertebral body similar to a long-bone torus fracture to a complete collapse of a portion of the centrum. Milder forms are usually asymptomatic, but there may be persistent local tenderness. Chronic vertebral compression forces such as occurring in trampolining or horseback riding accidents are usually diagnosed without difficulty except for the active adolescent with end-plate irregularities. Vertebral margin irregularities usually point to old trauma or infection. Comminuted fractures are the result of greater trauma in which the vertebra is severely shattered by either direct violence or another vertebra impacting it.
Scapular fractures are not frequently seen. In severe trauma, however, fractures of the body and spine of the scapula can occur. The strong muscular attachments usually prevent significant displacement. All that is usually required in uncomplicated cases is rest in a sling until acute pain subsides, then early mobilization. In rare cases, the brachial plexus or axillary nerve may be injured. Fractures of the scapular neck (uncommon) are usually impacted and present little displacement. Acromion fractures are the result of a downward blow on the shoulder, often leading to avulsion of the brachial plexus. Fractures of the coracoid process, easily confused with an ununited epiphysis, are uncommon; and when they occur, they are usually associated with acromioclavicular separations. Brudzinski’s test: A positive sign is elicited when the patient’s head is passively flexed toward the chest that is followed by involuntary flexion of the lower limbs. Such a reaction is indicative of meningeal irritation. The neck is rigid and painful to flexion and, in most cases, also to rotation. This test is unreliable in children below 2 years of age. Trousseau’s line test: This sign of meningitis consists of a bright red line produced where the finger is drawn across the trunk or forehead.
Unlike the rectangular centrum of a cervical or lumbar vertebra when viewed laterally, the body of a thoracic vertebra is wedge shaped, with its posterior aspect 1—2 mm higher than its anterior aspect. For this reason, lines drawn through the inferior vertebral body planes on a lateral roentgenograph normally meet anteriorly. This osseous wedge produces the relatively stiff primary thoracic kyphosis and encourages acquired exaggeration after prolonged axial loading. Cailliet points out that electromyographic studies on paraspinous muscles in idiopathic scoliosis fail to reveal significant muscle activity on either side of the curvature. Roaf’s experiments have added to the complexity of understanding the etiology in all cases of scoliosis. He shows that unilateral shortening (eg, abdominal wall hypertonicity) of the prevertebral components of the spine relative to the posterior components results in severe lateral distortion of the spine. This would appear to support but not necessarily confirm the theory of T. J. Bennett that many situations of scoliosis are the result of noxious viscerosomatic reflexes.
The major muscles of the trunk, their functions, and their innervation are shown in Table 11.1.
The study of the thoracic spine is often perplexing. It was Gillet’s opinion that many fixations found in the thoracic spine were secondary (compensatory) to focal lesions in either the upper cervical spine or the sacroiliac joints. Thus, a maze of potential variables exists. Empiric evidence shows many thoracic problems have their origin in its base, the lumbar spine or lower, while others are reflections of cervical reflexes. Also, a thoracic lesion may manifest symptoms in either the cervical or lumbar spine. Foremost in an examiner’s thoughts should be the recognition that the thoracic spine is the structural support and sympathetic source for the esophagus, heart, bronchi, lungs, diaphragm, stomach, liver, gallbladder, pancreas, spleen, kidneys, and much of the pelvic contents.
Screening Thoracic Vertebral Fractures
Thoracic fractures occur most frequently at the T12 transitional area, next in the midthoracic (kyphotic apex) region. Most are compression fractures with collapse of a vertebral body. Midthoracic fractures generally result from falls on the pelvis or when the head is severely forced between the knees.
Fractures of the thorax sometimes occur during convulsions or seizures, and usually occur in the T5—T7 region. The mechanism is strong abdominal contraction accompanied by paraspinal cervical and lumbar spasm. This places the midthoracic area under severe compression forces.
Gozna/Harrington point out that bending moments and axial compressive forces produce compressive normal stresses that are cumulative at the anterior portion of the thoracic spine. They feel this fact explains the high incidence of spinal fracture in the thoracic region.
The Soto-Hall test is primarily employed when fracture of a vertebra is suspected. The patient is placed supine without pillows. One hand of the examiner is placed on the sternum of the patient, and a mild pressure is exerted to prevent flexion at either the lumbar or thoracic regions of the spine. The other hand of the examiner is placed under the patient’s occiput, and the head is slowly flexed toward the chest. Flexion of the head and neck toward the chest progressively produces a pull on the posterior spinous ligaments from above. When the spinous process of the injured vertebra is reached, acute local pain is experienced by the patient.
Fracture lines are rarely recognized within vertebral bodies unless the area is crushed. These fractures are usually the result of considerable violence such as sudden extreme flexion, a heavy crushing injury, or extreme muscular exertion. Abnormalities in outlines and relations with neighboring vertebrae are the usual findings, especially in the lateral view. There are two general centrum types of fracture, compression and comminuted.
Neural Arch Fractures. In comparison to vertebral body fractures, fractures of the neural arch including the articular processes are more disabling because of the neuroreceptor irritation increased by motion or distortion. Fortunately, they are infrequently seen. Demonstration of a definite break is often difficult in the thoracic region, but callus formation later offers indirect evidence. Unlike vertebral bodies, the posterior aspects of the motion unit readily form callus that becomes calcified in a few weeks. Severe acute traumatic subluxation may call attention to a subtle fracture.
Transverse Process Fractures. Fractures of the transverse processes are usually multiple among adjacent vertebrae, but single processes may be broken by a blow from a sharp object. A slight callus can be expected, and fibrous union sometimes develops. Black lines formed by muscle shadows crossing transverse processes should not be confused with fracture. Muscle lines are smooth, straight, and extend beyond the bony margins.
Fracture vs Infection. Traumatic lesions are sometimes difficult to distinguish from infectious lesions. Traumatic lesions usually reveal a substantial portion of the intervening disc still present, while the disc commonly disappears or greatly thins in infection. The infectious process is frequently accompanied by or an extension of a paravertebral abscess.
Because hyperextension is strongly resisted in the thoracic region, which is normally in a state of structural flexion in the neutral position, fracture of the posterior element is rare. The biomechanical explanation is again offered by Gozna/Harrington: “The distance between the flexion axis and the tip of the spinous process is three to four times greater than the distance between the axis and the anterior margin of the vertebral body. Therefore, when exposed to flexion stress, the anterior portion of the vertebral body experiences a compression load that is three or four times greater than the tensile load falling upon the spinous processes and supraspinous ligaments.” Because of this, these researchers believe that hyperflexion forces will always produce an anterior wedge-shaped fracture of the vertebral body but never an avulsion or ligament rupture at the posterior element.
Fortunately, gross neurologic damage and severe disability are rare. Adequate management in uncomplicated cases can usually be provided by bed rest followed by extension exercises to stretch and strengthen the affected muscles. A light brace or corset should be worn initially by the patient when ambulated.
Pain, both local and referred, and paravertebral thoracic spasm are common manifestations of local and/or visceral disorder. The possibility of myelopathy, nerve root irritation, and bone disease should be weighed against the common complaints of a postural origin. Arthrosis, spondylosis, osteochondrosis, gout, and osteoporosis are common pathologies affecting the thoracic spine producing or contributing to biomechanical faults and spinal distortions affecting spinal design, dynamics, and equilibrium. Only a thorough physical, orthopedic, neurologic, and roentgenographic examination will help differentiate the many possible syndromes that have their origin in the thoracic spine.
A screening test can be performed by having the patient sit or recline while the examiner holds digital pressure over the jugular veins from 30—45 seconds (Naffziger’s test). The patient is then instructed to cough deeply. Pain following the distribution of a nerve may indicate nerve root compression. Though more commonly used for low back involvements, thoracic and cervical root compression may also be aggravated. Local pain in the spine does not surely indicate nerve compression; it may suggest the site of a strain, sprain, or another lesion.
Naffziger’s test is almost always positive in the presence of cord tumors, particularly spinal meningiomas. The resulting increased spinal fluid pressure above the tumor causes the growth to compress or pull sensory structures to produce radicular pain. The test is contraindicated in geriatrics, and extreme care should be taken with anyone suspected of having atherosclerosis. In all cases, the patient should be alerted that jugular pressure may result in vertigo.
Osteochondrosis of the vertebral plates is commonly associated with backache (thoracodynia) and round shoulders in adolescents. It can be asymptomatic and is unlikely to be associated with sports injury except when activity results in a superimposed injury. This growth disturbance of the vertebral epiphyseal ring results in deformity of the vertebral end plate with formation of Schmorl’s nodes, vertebral body wedging, and a smooth kyphosis. Taut hamstrings are often associated. Unless symptoms and signs are severe, corrective adjustments and therapeutic exercises may allow continued sports participation.
To check for ankylosis, chest measurements are taken after the patient inhales and exhales completely (chest expansion test). A 2-inch difference is a negative sign (may be less in females). A positive sign is indicated by no or very little difference in measurements and suspect of spinal ankylosis or spondylitis. Roentgenography offers confirmatory evidence.
Two physical tests are helpful in supporting a suspicion of meningitis:
ARTHROKINEMATICS: PERTINENT FUNCTIONAL ANATOMY OF THE THORACIC SPINE
The Articular Facets
The flat oval superior articular facets face posterior and superior near a 60° angle, with a slight lateral slant to match the inferior facets above. From above, they appear as an arc of a circle whose axis is slightly anterior to the vertebral body.
A common error in adjusting the thoracic spine is to direct the force closer to an 80° angle than the proper 60° angle. An improperly directed force on facets produces a jamming, rather than a sliding, action resulting in articular trauma. However, one should rely on individual roentgenographic findings rather than textbook averages.
The Intervertebral Discs
Thoracic spine flexibility is minimal because disc height in comparison to vertebral body height is less in the thoracic spine than that of any spinal region. This is readily apparent by noting there is little decrease in the thoracic curve on forward flexion or in the supine or sitting positions.
Unlike the cervical and lumbar regions, thoracic disc spaces are fairly parallel rather than wedge shaped. Thus, the primary thoracic kyphosis is produced by bone while the secondary cervical and lumbar lordoses are produced by fibrocartilage. Also, the thoracic nucleus sits slightly more central within the anulus. It is more posterior to the midline in the cervical and lumbar regions. This means the thoracic apophyses play less of a role in dispersing axial forces.
During axial rotation, oblique anular fibers running in the direction of rotation become tensed while those coursing in the opposite direction relax. This twists the anulus, but there are no appreciable shear forces involved in the thoracic spine during pure axial rotation.
The Spinal Muscles
As mentioned in earlier chapters, little muscle activity is necessary to maintain the erect posture if the weight-bearing structures are in good alignment and the ligaments are healthy. It would then appear logical that if distortion exists, greater muscle activity and ligament strength are necessary to maintain balance. Many medical and chiropractic authors emphasize this in scoliosis and exaggerated A-P spinal curves, as well as in hip deformities; genu varum, genu valgum, and recurvatum; pes planus, etc.
In most approaches to functional scoliosis, it has been presumed that the initial distortion is muscular in nature; ie, either agonist weakness on the side of the convexity or hypertonicity or spasticity of antagonists on the side of the concavity. Here, attention is on the strong posterior and intrinsic spinal musculature. This purely kinesiologic approach must be considered against facts brought out by recent research.
The Righting Reflexes
Experiments by Ponsetti and associates show unilateral labyrinthine stimulation or removal can result in scoliosis. This points to the delicate relationship between righting reflexes and spinal balance and offers an explanation to how cervical disrelationships with vertebral artery or vasomotor effects can produce scoliosis. Yamada et al found that 99 out of 100 scoliotic patients studied had an associated equilibrium defect and that the greater the spinal distortion, the greater the dysfunction in the proprioceptive and optic reflex systems. However, this finding has not been confirmed by research in this country.
The Spinal Ligaments
In comparison to the cervical and lumbar regions, the elastic ligamentum flava and the anterior and posterior longitudinal ligaments are thicker and stronger. On the other hand, the interspinous and capsular ligaments are thinner and looser in the neutral position. These latter ligaments receive support from ligaments radiating from the costovertebral and costotransverse joints.
KINESIOLOGY OF THE THORAX
Table 11.1. Major Muscles of the Trunk
Severe biomechanical lesions of the thoracic spine are seen less frequently than those of the cervical or lumbar spine. But when they occur, they may be serious if related to disc protrusion or a dynamic facet defect. Shoulder girdle, rib cage, spinal cord, cerebrospinal fluid flow, and autonomic visceral problems originating in the thoracic spine are far from being uncommon. Common biomechanical concerns are the prevention of thoracic hyperkyphosis, flattening, or twisting, as each can contribute to both local and distal, acute and chronic health-threatening manifestations.
Compression fractures vary from a single slight irregularity in the anterior or lateral margins of the vertebral body similar to a long-bone torus fracture to a complete collapse of a portion of the centrum. Milder forms are usually asymptomatic, but there may be persistent local tenderness. Chronic vertebral compression forces such as occurring in trampolining or horseback riding accidents are usually diagnosed without difficulty except for the active adolescent with end-plate irregularities. Vertebral margin irregularities usually point to old trauma or infection.
Comminuted fractures are the result of greater trauma in which the vertebra is severely shattered by either direct violence or another vertebra impacting it.
Scapular fractures are not frequently seen. In severe trauma, however, fractures of the body and spine of the scapula can occur. The strong muscular attachments usually prevent significant displacement. All that is usually required in uncomplicated cases is rest in a sling until acute pain subsides, then early mobilization. In rare cases, the brachial plexus or axillary nerve may be injured. Fractures of the scapular neck (uncommon) are usually impacted and present little displacement. Acromion fractures are the result of a downward blow on the shoulder, often leading to avulsion of the brachial plexus. Fractures of the coracoid process, easily confused with an ununited epiphysis, are uncommon; and when they occur, they are usually associated with acromioclavicular separations.
Brudzinski’s test: A positive sign is elicited when the patient’s head is passively flexed toward the chest that is followed by involuntary flexion of the lower limbs. Such a reaction is indicative of meningeal irritation. The neck is rigid and painful to flexion and, in most cases, also to rotation. This test is unreliable in children below 2 years of age.
Trousseau’s line test: This sign of meningitis consists of a bright red line produced where the finger is drawn across the trunk or forehead.
Unlike the rectangular centrum of a cervical or lumbar vertebra when viewed laterally, the body of a thoracic vertebra is wedge shaped, with its posterior aspect 1—2 mm higher than its anterior aspect. For this reason, lines drawn through the inferior vertebral body planes on a lateral roentgenograph normally meet anteriorly. This osseous wedge produces the relatively stiff primary thoracic kyphosis and encourages acquired exaggeration after prolonged axial loading.
Cailliet points out that electromyographic studies on paraspinous muscles in idiopathic scoliosis fail to reveal significant muscle activity on either side of the curvature.
Roaf’s experiments have added to the complexity of understanding the etiology in all cases of scoliosis. He shows that unilateral shortening (eg, abdominal wall hypertonicity) of the prevertebral components of the spine relative to the posterior components results in severe lateral distortion of the spine. This would appear to support but not necessarily confirm the theory of T. J. Bennett that many situations of scoliosis are the result of noxious viscerosomatic reflexes.
The major muscles of the trunk, their functions, and their innervation are shown in Table 11.1.
|External oblique||Rotation, flexion, forced respiration|
|Intercostals, external||Inspiration, extension|
|Intercostals, internal||Expiration, extension|
|Interspinalis||Extension, lateral flexion, rotation|
|Intertransversarii||Lateral flexion, rotation|
|Internal oblique||Rotation, flexion, forced respiration|
|Multifidus||Extension, lateral flexion, rotation|
|Rectus abdominis||Flexion, forced respiration|
|Rotators||Extension, lateral flexion, rotation|
|Semispinalis||Extension, lateral flexion, rotation|
|Serratus posterior inferior||Expiration|
|Serratus posterior superior||Inspiration|
|Transverse abdominis||Forced respiration|
KINEMATICS OF THE THORACIC SPINE
Movements in the thoracic spine are relatively limited compared to those of the cervical area, especially in the upper region, due to the restrictions imposed by the costovertebral and costotransverse articulations, the direction and shape of the articular facets, the relatively thin discs, and the tension of the ligamentum flava.
All thoracic movements are somewhat three-dimensional. Rotation and lateral flexion are the most evident. Movement of the thoracic spine cannot occur in any direction without the involved vertebrae somewhat carrying their attached ribs with them.
Flexion and Extension
Flexion and extension of the thoracic spine are quite limited. An average of only 4° occurs in the upper discs, 6° in the middle discs, and about 12° in the lower discs. As in the other spinal areas, excessive A-P motion is restricted by the check ligaments but the thoracic cage adds an additional mechanical barrier to flexion and intercostal straps to restrict extension.
Thoracic extension from full flexion takes places in two phases:
(1) The articular surfaces glide posterior and inferior, the interspinous spaces diminish, and the stretched posterior anulus of the disc returns to its normal shape as the individual achieves the erect position. There is no appreciable change in the anterior portion of discs or nucleus.
(2) It is not until the shingle-like facets, transverse processes, and spinous processes reach their limit as the spine is extended posteriorly to the midline that the anterior portion of discs and anterior intercostal spaces begin to widen. On forced extension, the articular processes impact. The vertebrae then push between their ribs, and the rib heads and their angles are moved slightly aside by the transverse processes.
Thoracic A-P mobility includes a good amount of facet gliding, but it is far less than that of the cervical region where the facets almost separate on forward flexion. Because of the rather limited normal movement of the thoracic spine, gross idiopathic scolioses in this area are difficult to comprehend when little structural damage is present.
As in other spinal areas, the anulus and its nucleus bulge in opposite directions during A-P and lateral bending moments to stabilize each other. During forced extension, the anulus thins and bulges posteriorly and stretches and contracts anteriorly. The nucleus bulges anteriorly without appreciable shifting. The anterior ligaments tense while the posterior ligaments relax. At the end of forced extension, the inferior facets tend to pivot open anteriorly as their posterior aspect jams on its neighbor below. These actions are fairly minimal when the normal kyphosis is present, but it may be exaggerated in the flat “military” spine. During flexion, the mechanisms are essentially the opposite.
Rotation of the thoracic spine, usually coupled with some vertebral body tilting, is somewhat greater than flexion and extension that are approximately equal in range. Rotation up to about 10° occurs at the T1 segment but progressively diminishes inferiorly to a maximum of 2°—3° at the T12 area. The total range of thoracic rotation is about 40°. Grice reports there are also a few degrees of coupled flexion during upper thoracic rotation and a few degrees of coupled extension during lower thoracic rotation. This becomes a significant point in analyzing scolioses.
During thoracic rotation, the spine does not rotate between the ribs but with the ribs. This is accompanied by a degree of lateral gliding of the vertebrae involved. However, when rotation is forced beyond the limit of rib motion, there is a slight push by the transverse processes against the rib heads on the side moving anteriorly and a slight pull by the transverse processes on the rib heads moving posteriorly. This motion is often revealed by palpation, rarely by roentgenography. It is recognized easier in the upper thoracic region where rotation is greater and the ribs are firmly attached to the sternum than in the lower thoracic area where the floating ribs more readily follow vertebral movement.
According to its design, the thoracic spine would have a considerable range of rotary motion if it were not for the restricting thoracic cage. This is seen in scoliosis, where every movement of the spine is registered by a corresponding movement in the attached ribs.
Although lateral flexion is hampered by the rib cage, the average person should be able to touch the ipsilateral knee with the fingertips. In the average adult spine, less than 10° of motion occurs at the upper and middle discs, and a few more degrees of motion are attained by the lower discs. The total range of lateral flexion for the healthy thoracic spine is slightly greater than 50°.
During lateral flexion in either the neutral or flexed (Adams) position, there is some coupled rotation where the upper vertebral bodies swing toward the concave side and the spinous processes rotate toward the convexity as in the cervical spine. This bending-rotation requires anterior transverse process movement pushing against the respective rib on the convex side and posterior transverse process movement pulling away from the rib on the concave side. This is the primary restricting mechanism. The ligaments play only a minor role except in traumatic forces.
In the lower thoracic segments, the vertebral bodies swing toward the convex side and the spinous processes rotate toward the concavity as in the lumbar spine. However, Grieve states that an opposite effect occurs during lateral flexion when the spine is in the extended position and vertebral body rotation is toward the convexity in the upper thorax and toward the concavity in the lower thoracic region. This fact tends to explain how various primary subluxations influence the direction a scoliosis will take; ie, a focal vertebral motion unit locked in either neutral, flexion, or extension.
Some authors give more credit to the thoracic ligaments than they deserve because they study the thoracic spine separate from the rib cage. But it is not separate in vivo, and studying the spine by itself does not reveal the total mechanics involved (eg, using a plastic model of the spine). A thoracic spine detached from the rib cage is fairly flexible in all directions except extension.
If the thoracic ligaments are supple (eg, those of a child), the ribs react to this movement of the transverse processes and enhance rotation. The rib spaces on the convex side will not open until the ribs on the concave side have reached their limit of approximation. In the adult thoracic spine, however, there is little rotation accompanying lateral bending except in the lower thoracic region where the ribs “float.” On forced lateral bending where the ribs approximate on the concave side and their limit is reached, the associated vertebrae are capable of slight additional lateral gliding.
Note: The position of a thoracic vertebra in lateral flexion is identical to that of the common subluxation in the neutral position where one facet has slipped inferoposteriorly while its counterpart has glided superoanteriorly.
As explained previously, it is fallacy to consider the thoracic spine biomechanically apart from the rib cage. The attached ribs, although individually quite flexible, offer increased stiffness and strength to the vertebral segments. The thoracic spine’s moment of inertia is increased by the rib cage, which also increases the area’s stiffness against torques and bending moments. The stiffness property of the thoracic spine is decreased at least in half in all loading directions once the ribs are removed.
It has been explained that the thoracic cage is stressed during axial rotation so that the ribs are pushed posteriorly on the side of movement and pulled anteriorly on the other side. This subjects the sternum to shear forces, and the sternum minutely tips obliquely toward the direction of rotation.
Unique Factors of the Thoracic Spine
Several unique factors arise regarding the stability of the thoracic spine have been explained. The major points are that it:
(1) is stiffer,
(2) is less mobile,
(3) has a smaller vertebral canal,
(4) has a high incidence of cord damage associated with structural damage,
(5) offers less vascularity to the cord,
(6) has restricting costal articulations,
(7) has an increased moment of inertia because of the added thoracic cage,
(8) has an anatomic curvature directed posteriorly,
(9) tends to be clinically unstable during flexion,
(10) has relatively thin discs,
(11) is a common site for bursting anterior centrum fractures (lower region only),
(12) has the nuclei more centered within the anuli,
(13) has thicker yellow ligaments,
(14) has thinner and looser apophyseal capsules,
(15) has thinner and weaker interspinous ligaments,
(16) has a great resistance to extension,
(17) possesses coupling variants from top to bottom, and
(18) is the major source of supply of sympathetic fibers.
BIOMECHANICAL ARTHROLOGY OF COSTOVERTEBRAL AND COSTOTRANSVERSE JOINTS
In terms of biomechanical stability, the costovertebral joints exhibit their highest stiffness property in the lateral direction and their lowest stiffness against superior or inferior loading. The sternocostal joints are just the opposite. They exhibit higher resistance against vertical forces and lower resistance against A-P forces.
The Costovertebral Joints
Posteriorly, the convex-shaped head of a rib articulates (slides and pivots) upon two adjacent thoracic vertebral bodies at the concave demifacets, above and below disc level. This occurs within a richly innervated synovial joint. Exceptions to this motion are the 1st rib and floating ribs whose heads articulate with only one vertebra.
The capsule of a costovertebral joint is typically quite thin and weak by itself but stronger anteriorly than posteriorly. It is attached to the anulus via the intermediate intra-articular ligament, which divides the cavity and attaches to the rib head between the facets. Interosseous fibers also extend from the rib head superiorly to the vertebral body above and inferiorly to the vertebral body below. These intermediate, superior, and inferior fibers greatly strengthen the inherently weak capsule proper. Capsule fibers merge posteriorly with the lateral extensions of the posterior longitudinal ligament. During inspiration, the rib heads undergo a slight rotatory and gliding movement.
The Costotransverse Joints
As a rib is directed posteriorly from the attachment of its head, a convex posterior tubercle on the rib articulates with a concave facet on the anterior tip of the transverse process of the same vertebra. This is also a richly innervated synovial joint that allows lubricated movement. The T1—T7 joints are concave-convex shaped to allow rotation, while the T8—T10 joints are flat to allow gliding.
Strength is provided to the thin capsule by medial and lateral costotransverse ligaments. A strong superior costotransverse ligament connects an adjacent rib neck below to the transverse process above, but it offers only slight protection to the costotransverse capsule. During inspiration, the tubercles glide superiorly and posteriorly. The lower two or three ribs have neither articular tubercles nor costotransverse joints.
Costovertebral and Costotransverse Coupling
Kapandji points out that the costotranverse joint and the costovertebral joint serve as a mechanical couple restricting normal movement to only rotation about an axis that passes through the center of each of these joints. These joints, along with the elasticity of the sternocostal articulations, produce pivot points from which the ribs elevate and depress laterally.
Because the axis running through the costotransverse and costovertebral joints lies close to the frontal plane in the upper ribs and nearly parallel to the sagittal plane in the lower ribs, elevation of the ribs during inspiration appreciably increases only the A-P diameter of the upper thorax, increases both the A-P and transverse diameters in the mid thorax, and increases only the transverse diameter of the lower thorax. All these changes of thoracic diameter can be accomplished by the diaphragm itself.
For every 3° of lateral arm abduction, 1° occurs at the scapulothoracic articulation for every 2° at the glenohumeral joint. If you wish to check solely glenohumeral joint passive abduction, your stabilizing hand should anchor the scapula while your active hand passively abducts the patient’s arm horizontally. The shoulder blade will normally not be felt to move until about 20° of abduction have occurred. Abduction normally continues in this position to about 120° where the surgical neck of the humerus meets the tip of the acromion. Then turn the patient’s forearm to externally rotate the humerus, turn the surgical neck away from the acromion, and continue abduction to its maximum.
Abduction is painful against resistance in shoulder tendinitis. In the “frozen shoulder” syndrome, scapulothoracic motion will be normal and glenohumeral motion will be absent.
1. STAGE OF ACUTE INFLAMMATION AND ACTIVE CONGESTION
The major goals are to control pain and reduce swelling by vasoconstriction, compression, and elevation; to prevent further irritation, inflammation, and secondary infection by disinfection, protection, and rest; and to enhance healing mechanisms. Common electives include:Disinfection of open skin (eg, scratches, abrasions, etc) Cryotherapy Cold packs Ice massage Vapocoolant spray Pressure bandage Protection (padding) Indirect therapy (reflex therapy) Iontophoresis/phonophoresis Auriculotherapy Meridian therapy Spondylotherapy Mild pulsed ultrasound Rest Bedrest Foam/padded appliance Shoe orthotic Shoelift Immobilization Brace Rigid appliance Strap Full-torso stayed corset Plaster cast Indicated diet modification and nutritional supplementation.
2. STAGE OF PASSIVE CONGESTION
The major goals are to control residual pain and swelling, provide rest and protection, prevent stasis, disperse coagulates and gels, enhance circulation and drainage, maintain muscle tone, and discourage adhesion formation. Common electives include:Indirect articular therapy (reflex therapy) Alternating superficial heat and cold Pressure bandage Protect lesion (padding) Light nonpercussion vibrotherapy Passive exercise of adjacent joints Mild surging alternating current Mild pulsed ultrasound Phonophoresis Pool cryokinetics (passive exercise) Meridian therapy Spondylotherapy Rest Bedrest Foam/padded appliance Shoe orthotic Shoelift Immobilization Brace Rigid appliance Strap Plaster cast Indicated diet modification and nutritional supplementation.
3. STAGE OF CONSOLIDATION AND/OR FORMATION OF FIBRINOUS COAGULANT
The major goals are the same as in Stage 2 plus enhancing muscle tone and involved tissue integrity and stimulating healing processes. Common electives include:Mild adjustment technics Moist superficial heat Thermowraps Spray-and-stretch Pool cryokinetics (active exercise) Moderate active range-of-motion exercises Meridian therapy Alternating traction Sinusoidal current Ultrasound, continuous Phonophoresis Vibromassage High-volt therapy Interferential current Spondylotherapy Mild transverse friction massage Mild proprioceptive neuromuscular facilitation techniques Rest Bedrest Foam/padded appliance Shoe orthotic Shoelift Semirigid support Indicated diet modification and nutritional supplementation.
4. STAGE OF FIBROBLASTIC ACTIVITY AND POTENTIAL FIBROSIS
At this stage, causes for pain should be corrected but some local tenderness likely exists. The major goals are to defeat any tendency for the formation of adhesions, taut scar tissue, and area fibrosis and to prevent atrophy. Common electives are:Deep heat Articular adjustment technics Spondylotherapy Local vigorous vibromassage Transverse friction massage Spray-and-stretch Active range-of-motion exercises without weight bearing Motorized alternating traction Negative galvanism Ultrasound, continuous Sinusoidal and pulsed muscle stimulation High-volt therapy Interferential current Meridian therapy Proprioceptive neuromuscular facilitation techniques Rest Bedrest Shoe orthotic Shoe orthotic Shoelift Semirigid support Indicated diet modification and nutritional supplementation.
5. STAGE OF RECONDITIONING
Direct articular therapy for chronic fixations Progressive remedial exercise Passive stretching Isometric static resistance Isotonics with static resistance Isotonics with varied resistance Plyometrics Aerobics Indicated diet modification and nutritional supplementation.
Grieve points out that it is a rare thoracic spine that does not exhibit some areas of tenderness when palpated. There are probably more trigger points and reflex fasciculations located on the thoracic cage than any other area of the body.
The thoracic region can be considered a highly critical zone, even though the predominance of current literature emphasizes the importance of its neighboring regions. It can be said that the thoracic spine suffers the “middle child syndrome” from an orthopedic viewpoint. It is just as important as its structural brother and sister above and below, yet fails to receive the same attention. May we remember that chiropractic pioneers took their greatest steps forward when “Meric analysis” was in vogue —long before our preoccupation was placed upon the atlas and sacrum. These were the days when the profession was accused of being undereducated and overmotivated. But these were the days when chiropractic “miracles” were taken for granted.
Postural Disorders of the Upper Trunk
To gather as many facts as possible during differential diagnosis, a comprehensive postural evaluation should include a comparative analysis of the physical signs found in the standing, sitting, Adams, prone, and supine positions.
Many clinicians believe that the causes of pain and discomfort in the shoulder girdle can usually be traced to muscular overuse leading to lower cervical or upper thoracic subluxations. While this is often true, fixed misalignments may be found in the shoulder girdle, especially when the scapulae are chronically affected. Acute or chronic fibrositis of the trapezius and rhomboids with trigger points is often superimposed or consequential. Such syndromes are often found in typists, assembly-line workers, and laborers who work overhead with repetitive motions for long durations with little postural change.
Note: Because chiropractors see so many neuromusculoskeletal conditions arising from the spine, it takes self-discipline not to develop tunnel vision because of these experiences. The author has served as a consultant in five cases during the last 2 years in which the patient complained of paresthesia (eg, numbness) in one or both index and middle fingers in which a thorough trial of cervical adjustments failed to bring adequate relief. All five cases had been diagnosed by allopaths as having carpal tunnel syndrome. It was found that one patient was suffering diabetic neuropathy, another advanced arteriosclerosis, and the remaining three experienced permanent relief simply by correcting fixations existing in the elbow (two patients) or wrist (one patient). Thus, we should not overlook the fact that the spine is just one area in which the vasomotor system may be adversely affected.
Postural Patterns and Classes
Any postural pattern is a reflection of an individual’s biomechanics responding to underlying processes. The process may be essentially antalgic, muscular, ligamentous, osseous, proprioceptive, or a combination of these factors.
DeJarnette believed that many idiopathic patterns reflect massive movement of structure held in a state of fixation by increased myosensory input. Goodheart places emphasis on muscular weakness, usually of a reflex etiology, and Barge feels the initial distortion is frequently the result of a nuclear shift. B. J. Palmer felt they were the result of proprioceptive or motor disturbances originating in the upper cervical area, and Hugh Logan felt they were responsive mechanisms to sacral base inferiorities. Today, few would disagree that all such mechanisms can be involved singularly or in combination.
There is always a danger in describing classic patterns because they lead to such variances in subjective interpretation. There is almost no limit to the possible distortions that may occur. Classifications tend to encourage the examiner to try to fit an individual’s unique distortion into a certain arbitrary category. This limits thought and can lead to error. Patterns only offer visual clues that require challenging by standard diagnostic procedures.
Standard muscle testing and inspection may disclose a pathologic weakness in the absence of palpable or measurable atrophy. This type of relative muscle weakness in comparison to its antagonist is often associated with a palpable trigger point at the origin and/or insertion of affected muscles. For example, a weak quadratus lumborum is frequently found associated on the side of pelvic slant and lumbar rotation (eg, a functional short leg). If this is the case, increasing the muscle’s strength tends to normalize the pelvic level and consequent thoracolumbar rotation. Any distortion produced by muscular hypo- or hyper-activity is an indication of debilitating postural stress.
Postural Realignment and Structural Fixations
The entire thoracic region is prone to a number of types of muscular and ligamentous vertebral and costovertebral fixations. Gillet believed that primary thoracic fixations generally tend to produce secondary areas of fixation in the cervical spine.
The lower thoracic region (T9—T12) is probably more prone to fixation than any other area of the spine. This is likely due to the abrupt change in facet planes between the superior and inferior processes of the transitional vertebra, the altered stiffness between thoracic and lumbar vertebrae, the lack of strong supporting muscles enjoyed by the lumbar region, the lack of firm anterior support by the floating ribs, and the large compressive forces concentrated at this area. A sudden change in the stiffness properties of a structure at a given point subjects the structure to stress concentration at that point. This can lead to eventual failure.
General Realignment Through Myotherapy
In postural alignment of functional thoracolumbar curves, the common muscles requiring strengthening are:
(1) the quadratus lumborum on the side of concavity,
(2) the upper and lower trapezius and the major and minor rhomboids to improve scapular adduction and rotation, and
(3) the infraspinatus and teres minor to improve lateral rotation of the shoulder.
It is also unusual in thoracolumbar distortions that certain muscles do not need stretching such as:
(1) the quadratus lumborum on the side of lower thoracic convexity,
(2) the latissimus dorsi, teres major, and subscapularis to improve shoulder adduction and medial rotation, and
(3) the pectoral group to improve shoulder adduction and medial rotation. Invariably, stretching of the intercostals on the side of thoracic concavity is necessary.
The common muscles to be stretched in postural misalignment restricted to the thoracic spine and shoulder girdle are the shoulder adductors and medial rotators; eg, the latissimus dorsi, teres major, subscapularis, and pectoralis major and minor. When these muscles are stretched, the scapula should be firmly stabilized.
In the therapeutic alignment of the thoracic spine and the shoulder girdle following adjustive therapy, the common muscles to be strengthened are the scapular adductors and rotators; eg, trapezius, rhomboid major and minor, infraspinatus, and teres minor. An associated weakness will invariably be found in the gluteals and abdominals, inducing primary or secondary pelvic misalignment.
Specific Muscle Hypertonicity
Most fixations seen in the thoracic area are muscular in type. This is fortunate because difficult to manage fibrotic pseudoankylosis can readily develop in the thoracic spine. While this would not contraindicate manipulation, the tough tissues adapt slowly. Correction takes frequent care using a wide scope of therapy over many months, if not years, to obtain an appreciable change because of the poor vascularity of the tissues involved.
The Interspinous and Intertransverse Muscles. Bilateral interspinous and/or intertransverse muscle hypertonicity produces extension fixation. In unilateral intertransverse hypertonicity, the involved transverse processes approximate, the discs thin ipsilaterally and the height of the IVFs is reduced. The superior articulation is pulled into a stressed position away from the inferior process (facet syndrome). The articular spaces have an abnormal V-shaped appearance. The IVD spaces increase at the anterior and decrease at the posterior. The acute stage is due to muscular spasm. But in prolonged conditions, the ipsilateral muscles become fibrotic and the paravertebral ligaments shorten. Stretching occurs on the contralateral side.
The Rotatores. A unilateral hypertonic rotatores, which courses in the groove between the spinous and transverse processes, will pull the corresponding spinous process into rotation and the transverse process below into counterrotation, similar in effect to that of intertransverse hypertonicity. This unilateral state, usually acute, commonly extends over several thoracic segments.
Bilateral rotatores hypertonicity, often a generalized reflex condition in the thoracic spine, tends to initiate the interspinous syndrome. Rotation is restricted and lateral bending is almost nil. This state is more readily palpable in the upper dorsal area and usually accompanied by bulging levator costarum muscles. Gillet believed that this disorder is frequently secondary to a primary fixation in one or both feet.
The Rhomboids. The rhomboideus major arises from the spinous processes of T2—T5 and inserts at the vertebral margin of the scapula. The rhomboideus minor connects the spinous processes of C7—T1 and the lower part of the nuchal ligament to the vertebral margin of the scapula at the root of the scapular spine. As their function is to retract and fix the scapula, hypertonicity of these muscles produces this normal function in a fixed state. In unilateral involvement, the scapula is pulled medially and upward so that the ipsilateral shoulder is higher than the other. This condition, often secondary, is infrequently symptomatic even though a postural distortion may be quite evident.
The Anterior Longitudinal Ligament. Shortening of the anterior longitudinal ligament is a common site of fixation in the thoracic spine, but it’s rare in the lumbar region. It displays on a lateral roentgenograph as an increased kyphosis and decreased anterior disc spaces and may be confused with anulus degeneration, which may or may not be present. IVFs will appear elongated. Gillet felt that this traction appears to have considerable effect on the sympathetic nerves (visceral symptoms), be a source of noxious reflex activity, but have little or no effect on the somatic nerves.
The Posterior Longitudinal Ligament. For some unexplained reason, shortening of the posterior longitudinal ligament is rarely found. This could possibly be explained by the greater flexion exercise required in normal activity, keeping in mind that A-P and P-A thoracic motion is minimal at best. While this may explain the thoracic state, one would think that these ligaments would be shortened in chronic cervical or lumbar lordosis but this is rarely demonstrated.
Most trapezius bruises will be found in the proximal portion, rarely distal to the scapular spine. That aspect between the occiput and the shoulder is the only significant muscle that can resist forceful shoulder depression. It is also this aspect that suffers contusion from a blow to the body from above that strikes lateral to the neck.
Management. The grade of trapezius injury parallels its disability, from minor to crippling, depending on the degree of related spasm and pain. Treatment consists of initial cryotherapy followed by correction of concomitant subluxations, radiant heat, frequent hot showers, trigger-point therapy, and vibrotherapy or massage to reduce spasm and congestion and encourage healing.
THORACIC SPINE OVERSTRESS
Posterior Thoracic Strain
The upper trapezius strain syndrome, often loosely labeled cervical fibrositis, is frequently found in patients who have a postural forward head displacement. The head position, which may be compensatory, is associated with a fixed rounded (kyphotic slump) curvature of the upper spine, resulting in fixed hyperextension of the cervical spine and restricted hyperflexion of the upper thoracic spine.
Undue spinal compression posteriorly (on the facets of the vertebrae) is characterized by a flattened area within the normal thoracic kyphosis. The typical clinical picture is posterior neck pain, weakness of anterior neck flexors, and tenderness of the upper dorsal transverse processes. Tension of neck extensors, including the upper trapezius and cervical erectors, causes chronic fatigue and an ache at the base of the neck. The patient frequently stretches the lower neck in an attempt to gain relief. A related impingement of suboccipital nerves as they emerge through fascia and muscle at the base of the skull may account for the commonly associated occipital headaches.
Middle Posterothoracic Strain. A painful mid-back disorder can result from gradual and continuous tension on the middle and lower trapezius fibers (a stretch-weakness condition). The chief problem is excessive tension on the posterior thoracic muscles. There is also a problem of undue compression on the anterior surfaces of the bodies of the thoracic spine, exhibited by hyperkyphosis and depression of the anterior rib cage. Common causes are habitual posture position of forward (round) shoulders and a rounded upper back, overdevelopment of the anterior shoulder girdle muscles with shortening, or heavy breasts that are not adequately supported.
Lower Posterothoracic Strain. This state of chronic muscle strain is rarely associated with an acute onset, but the symptoms may reach a point of severe pain after unusual physical activity. The syndrome is characterized by initial soreness and fatigue that progresses to a burning sensation within the course of the middle and lower trapezius. Traction by the muscle on its bony attachments may cause complaints of an isolated sore spot or trigger point. Palpation frequently elicits acute tenderness in the region of the dorsolumbar attachment of the lower trapezius.
Teres Spasm Sign
When the relaxed standing patient is viewed from behind, the arms normally rest so that the palms face the thighs. If a palm faces distinctly backward (toward the examiner) on the involved side, a spastic contraction of the teres major muscle is suggested.
Thoracic Spine Sprains
Acute traumatic spondylitis may follow contusions or wrenching of the spine. As in sprains of other joints, the symptoms are pain, tenderness, and reflex muscle rigidity limiting function. Symptoms may appear immediately after injury or not become apparent for a few hours or days. Diagnosis is based on history, physical findings, and x-ray to exclude fracture and destructive lesions.
Concomitant Vertebral Subluxation-Fixation. Posttraumatic thoracic subluxation complexes are managed in sports and industrial clinics as they are in general practice, but the athletic subluxation is more often associated with acute symptoms of paravertebral strain and sprain. Leverage adjustments on the medial transverse processes are preferred to pisiform recoil corrections with a spinous process contact. Because of the athlete’s heavy muscles, moist heat prior to correction is helpful, as a rule, in relieving spasm unless acute symptoms make this contraindicated.
Concomitant Thoracic Disc Herniation. Protrusion of a thoracic disc is the least common of any spinal region. It occurs predominantly in males over 50 years of age, commonly occurring in the T11—T12 area. The clinical picture is relative pain, usually unilateral in chronic cases or bilateral in acute cases, with girdle-like distribution. The pain may radiate to the abdomen, flank, or groin. Spastic paraparesis with sensory complaints may be involved. Bowel and bladder incontinence and impotence are infrequently associated. Motion restriction and tenderness on percussion may be the only local physical signs. Hyperactive tendon reflexes in the lower extremity and a positive Babinski are sometimes found. Common differentiations must be made from intercostal neuralgia, ankylosing spondylitis, metastatic or intramedullary spinal cord tumors, neurofibroma, disc-space infection, and viscerosomatic reflexes.
Management. During the acute hyperemic stage, structural alignment, cold, strapping or bracing, positive galvanism, ultrasound, and rest are indicated. After 48—72 hours, passive congestion may be managed by light massage, gentle passive manipulation, sinusoidal stimulation, ultrasound, and a mild range of motion exercise. During the stage of consolidation, local moderate heat, moderate active exercise, motorized alternating traction, moderate range of motion manipulation, and ultrasound are beneficial. In the stage of fibroblastic activity, deep heat, massage, active exercise, motorized alternating traction, negative galvanism, ultrasound, and joint manipulation speed recovery and inhibit postinjury effects.
Spinal rotation in scoliosis occurs posteriorly on the side of convexity of the curve and anteriorly on the side of concavity. This manifests as rib cage deformity (hump) in the thoracic area and bulging erector spinae in the lumbar area. The intercostal spaces are vertically stretched on the side of convexity and narrowed on the side of concavity. The normal contour of the entire thorax is distorted, taking on an oblique configuration rather than a relatively ovoid shape when viewed from above. This is produced so that the shoulders and head can be oriented forward —the effect of a biologic mandate rather than a biomechanical need.
Rib hump is readily observed in the Adams position and can be measured by various methods. Ribs do not distort by themselves; the distortion is essentially the result of vertebral rotation coupled with tilting. Thus, rib distortion offers an indirect measurement of spinal rotation.
In measuring in vivo rib cage distortion transverse to the apical vertebra, the doctor can apply the simple carpenter’s instrument used for measuring curved surfaces to which a small line level has been fixed. As the points of the instrument are quite sharp, a thin sheet of pliable plastic is placed on the patient’s back. This sheet should be thick enough to protect the patient’s skin, yet thin enough to conform exactly to the curvature present. The instrument is applied, then the curve formed is traced on a sheet of paper and made part of the patient’s progress record. This method may be used in the erect, prone, and Adams’ positions if desired. It can be used on any region of the spine and on extremity joints to record progressive changes in skin configuration (eg, swelling reduction).
The primary considerations involved in the treatment of any functional scoliosis is the application of correcting loads and the balancing of asymmetrical forces. This is usually strived for in chiropractic essentially by corrective segmental adjustments, the freeing of articular fixations, muscle balancing, traction, therapeutic exercise, and the use of corrective lifts and corsets. In any approach, basic biomechanical and bioengineering principles must be applied if the therapy is to be optimally successful.
Restricted movements are commonly found in the scapular area that influence physical performance and posture. Their usual causes are:
(1) the consequence of injury,
(2) trigger-point spasm, or
(3) viscerosomatic reflexes. The somatic source of the difficulty may be local, at the spine, or in the shoulder. The common loci to search first are a costovertebral or upper-thoracic subluxation, or spasm of any muscles that have a scapular attachment such as the rhomboids, trapezius, levator scapulae, supraspinatus, infraspinatus, or teres major and minor.
Evaluation. It was previously described that scapular motion cannot be conducted without a reciprocal action at the glenohumeral joint. To test involuntary scapular mobility, Mennell suggests that the patient be placed in a relaxed lateral recumbent position with the side of suspected mobility restriction upward. Stand behind the patient, and cup your caudad hand over the patient’s shoulder. Grasp the apex of the scapula with your other hand. This requires that the scapular is “winged” somewhat so that you can get your fingertips slightly beneath the blade. With both hands in the positions described, rotate the apex of the scapular downward and laterally while bringing the shoulder tip upward and medially to test scapular rotation on the chest wall.
Management. Scapular mobility should be found in all directions: superior, lateral, inferior, medial, and slightly clockwise and counterclockwise. If not, corrective manipulation is usually necessary. The procedure is conducted with the patient prone. Pressure is made with the base of the contact hand, the stabilizing hand is positioned on the wrist of the contact hand as in a toggle recoil, and the direction of thrust is into the restriction on almost a horizontal plane so that the underlying thoracic cage is not greatly disturbed. To inhibit recurrence, therapeutic exercises should be prescribed that will stretch the shoulder in flexion, extension, adduction, and horizontal abduction. Posttreatment commonly includes deep heat and interferential therapy followed by muscle therapy and passive manipulation to a degree just below pain expression or to stretch and relax the shortened connective tissues involved. After the acute stage, this procedure is often followed by chronic sprain therapy.
Strains and associated fibrositis are often seen in the muscle attachments to the vertebral border of the scapula from throwing heavy objects (eg, shot put). The initial trauma may not be remembered.
Clinical Features. Fibrositis is a general term referring to a syndrome of spasm, stiffness through the range of motion without limitation, a dull gnawing ache at rest that is aggravated by exercise, localized tenderness, possible soft-tissue crepitus, and one or more palpable trigger points. The disorder is most often seen in the rhomboids and trapezius. However, the levator scapulae, scalene group, or erector spinae may be involved. Fibrofatty nodules herniate through the superficial fascia of the involved muscles. Palpation and movements may cause pain to radiate up the posterior neck and/or over the shoulder and sometimes down the arm. Cervical motions cause a vague soreness in the affected tissues. This is usually worse in the morning after arising and during cold damp weather.
Management. Trigger-point therapy should be applied and a search made for the primary focus such as a postural defect, chronic subluxation, or disc lesion. Once primary trigger nodules are controlled, several secondary sites may appear that require therapy. Bony and soft-tissue adjustive technics, heat, massage, progressive passive manipulation, and active exercise will usually show excellent results. Initially, some soreness always follows muscle therapy that will be quickly relieved by a hot bath. The affected tissues enjoy warmth and prudent use. Chilling of the part should be avoided by the use of sweaters, etc. Instructions should be given for isometric exercises and to help develop proper postural and sleeping habits.
Winging is a distortion of the scapula in which the medial border flares overtly backward when the subject presses forward with the outstretched upper limb. When the involved arm is laterally abducted, the scapula pulls away from the chest wall in an abnormal manner so that the arm cannot be abducted much beyond the horizontal level. This occurs because the serratus anterior is unable to rotate the glenoid cavity upward.
Injury (eg, compression, laceration, or surgical trauma; viral infection) to the long thoracic nerve of Bell (C5 C7) can result in paralysis of the serratus anterior muscle. This is a pure motor nerve (without sensory fibers). Its winding course under the brachial plexus varies considerably from person to person, thus making localization difficult.
Clinical Features. Rarely found excepting athletics, winging features vague pains referred to the shoulder, a degree of abduction weakness, and visible scapula rotation when the arm is abducted laterally against resistance. Early diagnosis is important, yet there is rarely a complaint until marked atrophy has occurred. Muscular dystrophy must be excluded. Seek the slightest sign of winging while the patient’s hands “wall walk” with the elbows locked or while doing demanding pushups. Winging in the well-developed athlete is often disguised by heavy trapezius, latissimus, and rhomboid muscles.
Scapular winging is associated with postural faults that are a result of imbalanced function of the suspensory muscles of the shoulder girdle. Pain is referred to the shoulder region but not into the glenohumeral joint itself. A functional thoracic kyphosis may be found with alterations in scapulohumeral rhythm. A primary subluxation, which may have been present since childhood, may be found near the cervicothoracic transition or the apex of the thoracic curve. Secondary (sometimes primary) costovertebral fixations may also be found.
Management. Treat essentially as a chronic peripheral nerve contusion. Instruct the patient to discontinue strenuous work until symptoms subside. This is an absolute that will probably meet resistance in the young. Check for lower cervical subluxations, scapula fixations, and trigger points. Vitamin C and E supplementation, interferential therapy, and electric current stimulation (especially, pulsating) of the nerve 3 5 times a week during the early stage of rehabilitation is helpful in preventing atrophy while regeneration is in progress. Later, progressive exercises can be carefully initiated; eg, shoulder shrugging against resistance, overhead weights and springs, and pushups.
The Scapulocostal Syndrome
In this myofascial-periostitis, a trigger area is often found at the site of the attachment of the levator scapula muscle to the upper medial angle of the scapula. The mechanism is usually postural, causing tension traction irritation of the attachment site.
The related pain is perceived in the upper interscapular area and reported by the patient to be between the medial border of the blade and the underlying rib cage. The onset is often insidious. Discomfort may radiate to the:
(1) neck and occiput,
(2) upper triceps and deltoid insertions,
(3) around the chest to the anterior, or
(4) medial forearm and/or the hands and fingers where numbness and tingling are sites of complaint. The course is frequently chronic and characterized by remissions and exacerbations.
Suprascapular Nerve Entrapment
Entrapment of the suprascapular nerve infrequently occurs as the nerve passes through the suprascapular foramen, which is formed by the suprascapular notch and the transverse scapular ligament. The suprascapular nerve passes from C5 C6 roots to course under the clavicle and then divides to supply the capsule of the shoulder joint, the acromioclavicular joint, and the supraspinatus and infraspinatus muscles.
Entrapment may be the result of abrupt shoulder trauma, forcing the arm into severe adduction, of forward rotary stress of the scapula that is directed medially, and/or of traumatic acromioclavicular separation.
Clinical Features. The classic signs and symptoms include the reproduction of suprascapular pain (with possible radiation down the radial and/or median nerve) on adduction of the arm across the chest, pain increased while recumbent, weak infraspinatus and supraspinatus muscles, and minimal voluntary use of most all shoulder motions. Priority differentiation must be made from tenosynovitis of the rotary cuff, fracture, and radial nerve neuropathy.
Management. Correction of subluxations (primary or secondary) involving the C5—C6 roots, anti-inflammatory therapy to the suprascapular nerve, stretching of the transverse scapular ligament, and standard physiotherapy regimens for neuritis are the typical procedures applied. Shoulder manipulation should be avoided until any associated neuritis has subsided. Rehabilitative procedures commonly emphasize improving the function of humeral abduction, adduction, and internal and external rotation. Pendulum exercises are often helpful initially.
Normal vertebral rotation can be greatly impaired by a rib fixation because the ribs must move with the rotating transverse processes. Similarly, unilateral or bilateral hypertonicity of the rotatores, multifidi, and/or levator costorum restrict vertebral rotation. Such conditions are frequently found in the upper thoracic area. The intertransverse muscles may be a cause of fixation in the mid-to-lower thoracic area and can be best determined by intertransverse palpation during lateral bending.
COSTOVERTEBRAL AND COSTOTRANSVERSE JOINT SUBLUXATION-FIXATIONS
The articulations between the rib head and vertebral body or between the rib tubercle and the transverse are also common sites of fixation, typically due to serratus and/or levator costarum chronic hypertonicity or fibrosis. Gillet believed this type of fixation is contributed to by capsular shortening that allows enough torsion for unrestricted breathing during nondemanding activities. Associated adhesion-type bands could easily irritate an entrapped sympathetic ganglion during normal motion. Posterior rib fixations are rarely complete. They usually tend to restrict mobility in one or more directions but not in all directions.
These subluxations are featured by misalignment of the costal processes relative to the vertebral bodies and transverse processes independent of vertebral motion-unit subluxation (ie, primary) or misalignment of the costal processes relative to the vertebral bodies and transverse processes as a result of vertebral motion-unit subluxation (ie, secondary). They present with painful, difficult, and/or restricted respiratory movements of the ribs, shearing stress to the capsular ligaments and synovia, inducing a vertebral motion-unit subluxation and/or are contributory to the chronicity of a subluxation, induction of spinal curvatures and/or contribute to the chronicity of curvatures present, and irritation of the sympathetic ganglia and rami communicantes. Vague terms such as idiopathic pleurodynia or intercostal fibrositis are often used in medical literature to describe the disorder.
Clinical Features. Unilateral pain, which may be either stabbing or dull and usually episodic, may be expressed centrally and/or intercostally. The onset is usually rapid following a fall, push, misstep, stretch, sneeze, or cough. Transient but sharp neuralgia, angina, or dyspnea may be reported. Site tenderness, intercostal spasm, and tissue resistance are found at the rib angle and/or near the vertebral or sternal attachments. A midthoracic rib subluxation frequently produces pain that radiates down the lateral arm, sometimes mimicking a scapulocostal syndrome. Symptoms are frequently aggravated during deep inspiration when the trunk is flexed.
Evaluation. Unilateral asymmetry may be palpated below the axilla by noting that one rib is unusually shallow to the one above or below, indicating that some type of detraction mechanism is involved. Maurer points out that, in the nonscoliotic thoracic spine, detraction from the marginal line usually implies the existence of rotation alterations of the vertebral body to which the rib is attached (subluxation), flexion alteration of the same, or alteration of the costovertebral or costotransverse articulation. Detraction would obviously involve numerous soft-tissue changes also.
Posterior rib fixations resulting in decreased chest excursion can be determined by motion palpation of the thoracic cage during deep inspiration with the patient either standing or prone. First, traction the skin of the lateral thorax toward the spine with broad bilateral palmar contacts and place your thumbs near the dorsal midline on the rib being examined. As the patient inhales deeply, note if both thumbs move equally. If the rib rises and the interspace opens, it is considered normal. If it remains down or down to some extent compared with the opposite side, it is considered “locked.” Thumb motion restricted unilaterally suggests the side of fixation.
To determine the site and direction of a specific subluxation-fixation, Schoenholtz recommends that examination should be conducted when the patient is in the sitting position. The examiner should stand behind and ask the patient to laterally flex away from the painful side while lifting the ipsilateral arm over the head to open the ribs. As this is done, the examiner’s fingertips are placed under the lower border of the suspected rib and pushed upward. The maneuver is then repeated while the examiner’s fingertips are placed on the superior border of the suspected rib and downward pressure is exerted. Pain will be increased in the direction of subluxation.
Management. Once identified, a general rib-mobilization technique with and without traction on the ipsilateral iliac crest or shoulder can be applied on the angles of the ribs involved to loosen restrictions. This is usually best followed by a regimen of moist heat or interferential therapy, and graduated stretching exercises.
“Bucket Handle” Complications
Costovertebral and costotransverse subluxations, and less frequently costosternal subluxations, are frequently complicated by reflex spasms in the thoracic cage. Hypertonicity of the scalene group, levator costarum, cervical longissimus, cervical and thoracic iliocostalis, and/or serratus posterior superior tends to raise and displace the upper ribs superiorly. On the other hand, hypertonicity of the thoracic longissimus, lumbar iliocostalis, and/or serratus posterior inferior tends to depress and displace the lower ribs inferiorly. Such attending hypertonicities or weakness of the antagonists should be corrected prior to structural adjustment, or the structural correction will not likely hold.
Determining Associated Costovertebral/Costotransverse Sprains
Compressing the rib cage increases pain in fracture and sprain but not in intercostal strain. Springing the ribs P-A of the prone and relaxed patient to create stress at the vertebral connections aggravates symptoms and causes an immediate apprehensive muscle-guarding response in sprain and subluxation. Over-reaction should make the examiner suspicious of a hidden stress fracture.
Superior First Rib Head Subluxation
Of all rib-head subluxations, those of the short acutely curved 1st rib are the most common. The next incidences are the 2nd, 5th, and 6th ribs, respectively, according to Schultz. Palpation is aided if the patient’s scapula is adducted.
The 1st rib is frequently subluxated superiorly when lower cervical compression tests are positive as in scalenus anticus syndrome, cervicobrachial neuralgias, and various neurovascular shoulder girdle, arm, and hand syndromes. Superior subluxation obviously narrows the costoclavicular space and stretches the neurovascular bundle. It can also be the primary or a contributing factor in torticollis, herpes zoster, and vague anginal or breast aches. Some reports indicate that a superior 1st rib subluxation is frequently associated with quadratus lumborum muscle weakness and/or levator costorum and scaleni muscle spasm. The displacement mechanism is usually initiated by pushing with the elbows locked.
Adjustment. With the patient supine, stand on the ipsilateral side of the involved rib, facing caudally. With your lateral hand, take an open-web contact near the involved rib’s crest that is high on your lateral index finger, with your thumb anterior and your fingers posterior to the patient’s chest. The point of contact is about 4 or 5 inches lateral to the T1 spinous process. Cup your stabilizing palm over the patient’s contralateral ear, with the fingers supporting the occiput. To relax the ipsilateral neck muscles, raise the patient’s neck with your stabilizing fingers and let the occiput extend into your palm. Rotate the patient’s head about 25° away from the fixation, and make a moderate thrust directed inferior and slightly posteromedial toward T4.
Alternative Technic. With the patient prone, stand on the ipsilateral side of the involved rib facing the patient’s contralateral shoulder. With your lateral hand, take an open-web contact on the rib’s crest that is high on your lateral index finger as above. Your lateral elbow will be flexed and pointing superior-lateral as you lean over the patient. A palm contact is made with your stabilizing hand on the patient’s lateral occiput above the ear on the opposite side of involvement. With your stabilizing hand, slightly extend the patient’s head and rotate it away from the involved rib. Apply slight lateral flexion to relax the ipsilateral muscles, and make a thrust with your contact hand directed inferior-medial toward T4.
Superior Second Seventh Rib Head Subluxations
Palpation reveals an increased intercostal space below and a decreased space above the rib that has subluxated superiorly to its vertebral articulations.
Adjustment. This is essentially the opposite procedure to that for a 2nd 7th rib that is listed as inferior. With the patient prone, stand above the ipsilateral side of the involved rib, facing caudad. With your lateral hand, a thumb contact is made slightly above the superior border of the involved rib at the rib’s angle. With your medial stabilizing hand, take a pisiform contact over your contact thumb. Apply traction inferiorly to tighten the overlying tissues, and bring your contact thumb directly onto the rib’s superior edge. At the end of patient expiration, make a short, moderate, recoil thrust directed anterior-inferiorly.
Inferior Rib Head Subluxations
Palpation reveals increased intercostal space above and decreased space below the rib that has subluxated inferiorly to its vertebral articulations. Inferior-extension displacements are infrequent in comparison to superior-flexion subluxations and take much greater force to correct. The latter are more common at the lower ribs and exhibit with local pain that often radiates to the abdomen and splinting lateral flexion on the contralateral side.
Adjustment. With the patient prone, stand on the ipsilateral side of the involved rib, facing cephalad. With your lateral hand, apply a thumbpad contact just below the inferior border of the subluxated rib between the rib’s tubercle and angle. Your contact-hand fingers will overlap the scapula. With your medial stabilizing hand, apply a soft pisiform contact over your contact thumb. Apply traction superiorly to tighten the overlying tissues and to bring your contact thumb directly on the inferior border of the involved rib. Ask the patient to take a deep breath and to exhale. At the end of expiration, make a short, moderate, recoil thrust directed anterior-superiorly by quickly extending your elbows.
HERPES ZOSTER (SHINGLES)
Shingles (sometimes called zona) is an acute CNS viral (chickenpox family) infection involving the thoracic dorsal root ganglia; thus, an acute posterior ganglionitis. The virus appears to lie dormant in the body for many years, and then suddenly become active for some unknown reason.
Outward features (usually unilateral) include early erythemia followed in 3—4 days by small vesicular eruptions mounted on inflammatory bases and intercostal neuralgia in the dermatomes supplied by the involved peripheral sensory fibers. Thus, red blistery streaks arise from the spine and course along the intercostal spaces toward the sternum.
Conduct a thorough physical examination and consider appropriate laboratory profiles according to clinical judgment. Motion palpate the spine, and relate findings with the patient’s complaints. Check pertinent superficial reflexes, and grade the reaction. Test for autonomic imbalance if suspicions of vagotonia or sympathicotonia arise.
Release anterior and posterior rib fixations. Associated spinal majors will likely be found at C1 and T6—T11. After relaxing the tissues and adjusting the subluxated/fixated segments, apply deep high-velocity percussion spondylotherapy over segments T4—L1 for 3—4 minutes. Treat trigger points discovered, especially those found in the serratus anterior, middle trapezius, latissimus dorsi, and iliocostalis muscles. Cryotherapy is beneficial during the initial stage. Other helpful forms of treatment include applying ultraviolet radiation and coating the lesions with comfrey ointment. Ultrasound, galvanism, and interferential currents are recommended by several authorities, but the author has never found them necessary. Supplemental nutrients A, B-complex, C, niacin, pantothenic acid, and copper are recommended, as well as counseling the patient to avoid appropriate antivitamin and antimineral factors. Under chiropractic care, the course rarely exceeds 5 days.
INTERCOSTAL NEURALGIA AND COSTALGIA
The terms intercostal neuralgia and costalgia are synonymous; both mean rib pain of known or unknown origin. Some authors limit the phrase intercostal neuralgia to painful disorders involving the sensory fibers of the anterior rami of T1—T11 peripheral nerves. Both terms refer to the perception of pain (a symptom) and not a diagnostic entity.
Differentiation of a functional from a pathologic disorder must be made early. Costosternal pain may have its origin in an aortic, a cardiac, a gastric, or a mediastinal disorder. Sometimes a sternalis, pectoralis, scaleni, or subclavis trigger point will be at fault. In rare instances, it due to a fracture or sternocostal lesion. Frequently occurring thoracic, costotransverse, and costovertebral fixations are overlooked in traditional medical evaluation.
Besides obvious fracture, intercostal neuralgia, and trigger-point syndromes, Tietze’s syndrome is the most common cause of rib pain. The cause of this costochondritis symptom complex, which usually attacks the upper ribs, is unknown. There are ill-defined pain and localized tenderness. Swelling may or may not be associated.
Release anterior and posterior rib fixations. Associated spinal majors will likely be found at the T6—T9 level. After relaxing the tissues and adjusting the subluxated/fixated segments, apply deep high-velocity percussion spondylotherapy over segments T5—T10 for 3—4 minutes. Treat trigger points discovered, especially those found in the sternalis, pectoralis, scaleni, or subclavis muscles. Other helpful forms of treatment include early cryotherapy and spray-and-stretch trigger point therapy, followed by ultrasound, interferential therapy, iontophoresis with xylocaine, or high-voltage therapy. TENS is often helpful in situations of intractable pain. Supplemental nutrients B1, B6, and pantothenic acid are recommended. Counsel the patient to avoid appropriate antivitamin factors.
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