Current concepts in management of cervical spine fractures and dislocations ROBY C. THOMPSON, Jr, MD, J. N. MORRIS, Jr, MD AND JOHN A. JANE, MD
Neck
injuries in sports are among the dangerous the athlete faces. A recent survey of 84 cervical spine injuries&dquo; revealed that one-third of these injuries were sustained in sports activities. Fortunately, these severe injuries represent a small proportion of the injuries seen by the physician most
on sports medicine; however, the potential danger involved in these injuries and their treatment dictates an understanding of this problem for every physician caring for athletes. Significant neck injuries have been seen by the authors in athletes involved in football, basketball, gymnastics, wrestling, diving, skiing and all forms of vehicle racing. The clinician searching for an approach to cervical spine injuries is faced with conflicting views in the literature as to appropriate management.2.J.8.11.25 Recent controversy has centered around the use of anterior decompression and fusion9 1°,15,18.2’ versus traction and subsequent stabilization by
concentrating
nonoperative
means
or
posterior
fusion. 4.6.7,19 The choice of treatment in a given patient depends on the presence or absence of neurologic deficit. The neuro-
Roby C. Thompson, Jr., MD, Department of Orthopedic Surgery, University of Minnesota School of Medicine, Minneapolis, Minnesota. J.N. Morris, Jr., MD, Department of Orthopedic Surgery, University of Virginia School of Medicine, Charlottesville, Virginia. John A. Jane, MD, Department of Neurological Surgery, University of Virginia School of Medicine, Charlottesville, Virginia.
logic status of the patient must be protected and improved upon if possible. However, the treatment selected should avoid jeopardizing this status when viable alternatives are available. The type of injury present should determine the inherent stability of the cervical spine and suggest the best means for restoring stability after treatment has been terminated. In addition, consideration must be given to the rehabilitative, psychological, social and medical needs of the patient. By relating the patient’s injury to documented previous studies, appropriate treatment can be initiated which will protect his neurologic status, stabilize his injury through operative or nonoperative means and minimize his hospitalization. Holdsworth’s classification of injuries to the spine&dquo; was derived from the mechanism producing the injury. Cheshire’ modified this to relate directly to cervical spine injuries. The latter study of 257 cases of cervical spine injuries with neurologic deficit described the stability of the spine following nonoperative treatment in 212 cases. Treatment consisted of reduction of the deformity by traction or manipulation. Subsequent protection in skull traction for six to eight weeks was followed by a cervical collar or brace for a total of 12 weeks of immobilization. Assessment of stability was then made by radiographic examination of the cervical spine in flexion and extension. Using this study as a guideline, we treated 62 cervical spine injuries on the Orthopedic 159
and
Neurosurgical Services at the UniverVirginia between 1968 and 1973. Our approach was largely conservative since surgery was deemed necessary in only 17 of our sity
62
of
cases.
CLASSIFICATION OF INJURIES Classification of cervical spine injuries, according to the mechanism producing the injury, is a simple and useful way of determining treatment and prognosis. Flexion may occur with compression or rotation as secondary forces; the direction and magnitude of the force determines the extent of the injury.ls,za.l3 Flexion-compression injuries result in a simple compression fracture of the vertebral body when the
injuries
interspinous ligaments
are
not
disrupted
When the flextion force, being transmitted through the cervical spine, has a magnitude sufficient to produce disruption of the interspinous ligaments, a fracture of the vertebral body at or below the level of the disrupted posterior soft tissues may occur (Figure 1).~5 In contrast, a true vertical compression fracture produces a bursting injury of the vertebral body with the fragments of the body being displaced posteriorly and anteriorly (Figure 2).5 This fracture is uncommon in the cervical spine compared to the thoracolumbar junction and is most commonly seen in the neck with a bursting fracture of the ring of the first cervical vertebra (Jefferson’s fracture). When rotation is combined with a flexion force, facet dislocation or anterior subluxation occurs in the cervical spine (Figures 3 and 4).~ ~Extension injuries are identified by fractures of the posterior elements, avulsion of the anterior longitudinal ligament with or without a portion of the anterior body below the level of the injury. Extension injuries may sometimes involve complete posterior dislocation of a vertebral body (Figure 5).’,&dquo; Utilizing this classification of cervical spine injuries, Cheshire reported an overall incidence of instability (after 12 weeks of immobilization) of 5.4 per cent with a range from 0 to 7.3 per cent. Anterior subluxations, however, revealed an incidence of late instability of 21per cent. Odontoid fractures have been classified 160
and studied by several authors. In Cheshire’s series there were only eight atlantoaxial injuries out of 257 cases. This is a low percentage compared to most studies of cervical spine fractures.12,21 One would suspect that since all of his patients had neurologic deficit, a smaller proportion of atlantoaxial injuries reached his center, as most of these injuries either result in death or minimal neurologic defici t.22 Anderson’s classification of odontoid fractures allows prognostication of bony union as an end result based on the anatomic location of the fracture. In a retrospective study of nonoperative treatment in odontoid fractures, they found that fractures through the base of the odontoid (Figure 6) had a 37% nonunion
Figure
of the fifth cervical vertebral body with disruption of the interspinous ligaments between C5 and C6 posteriorlv. A flexion-compression injury with the inferior margin of the vertebral body above being avulsed by the vertebral body below.
I-Fraction
I
or a cervical brace was used for a minimum of 12 weeks. Thirty-seven of our 62 cases had either cord or nerve root injury, and 13 had associated head injuries. Five of the patients with neurologic deficit died. Three of the five patients had a complete cord lesion, and two of these underwent posterior decompression at two and three weeks post-injury respectively. One complete cord lesion patient died three weeks post-injury from a C5 level lesion managed with supportive care. Two of the five deaths occurred from a partial cord lesion. One of these patients died following laminectomy on the day of injury, and another elderly patient died of unknown causes three weeks after a C6-7 subluxation which had been reduced in traction and was showing progressive neurologic improvement at the time of death. None of the surviving patients showed an increase in neurologic deficit after admission to the hospital. Twenty of the 32 patients improved significantly, and seven of these underwent
cast
surgical
treatment.
DISCUSSION
Figure
2-Vertical compression fracture of sixth cervical vertebrae with compression of the vertebral bodv below by the vertebral body above and disruption of the posterior soft tissues at the CS-6 interspace. (Illustration shows patient in traction.)
rate whether
in down into the body of the second cervical vertebra (Figure 7) where only one out of 11nonunions was encountered.
displaced
or
undisplaced
contrast to fractures that extended
MATERIALS Our injuries were classified according to Cheshire’s criteria except for odontoid fractures where Anderson’s method was used. Ten percent of our cases involved odontoid fractures, 25% anterior subluxations, 8% flexion-rotation injuries with locked facets, 30% flexion-compression injuries, and 27% were extension injuries. Two of our patients had laminectomies, five had posterior fusions, and nine had anterior fusions. The remainder were treated by traction for three to six weeks, and then, either a halo body
With minor exceptions, our data support Cheshire’s findings that nonoperative treatment of most cervical spine injuries can be expected to produce a stable spine without increasing neurologic deficit. After reviewing the literature on cervical spine injuries and considering our own results, we have arrived at a scheme that allows the clinician to select a rational method to determine prognosis and a choice of therapy, in cases of cervical spine injury, best suited to the individual patient and surgeon. Our plan is to categorize the patient’s condition, first on the basis of his neurologic deficit, and second to classify the type of injury according to the method outlined above. In the patient with no detectable neurologic deficit (Table I), the neck injury may be a mild compression fracture of the vertebral body. Mechanisms of injury might have involved the presence of flexion forces, a simple sprain of the anterior longitudinal ligament, undisplaced fractures through the lamina, or lateral masses in the presence of extension forces. In these cases, sympto161
matic treatment with traction and subse-
quent protection using a cervical brace very often brings good results. If there displacement, we feel it should be
is bony reduced system protected from
and the nervous further damage by surgical or nonsurgical methods until stability of the cervical spine has been restored. In deciding on surgical versus nonsurgical methods of managing these injuries, we feel there are some absolute indications for stabilization of the cervical spine by operative methods (Table II). Under absolute indications, we include late instabilitv following closed treatment for anv injurv and flexion-rotation injuries where locked facet joints are unreduced bv closed means. In addition to these absolute indications, certain relative indications (Table III) for surgical stabilization in the neurologically normal patient would include those injuries where a relatively high incidence of late instability might be expected, such as anterior subluxations or fractures through the neck of the odontoid at its junction with the body of C2. When careful consideration is given to the patient with an anterior subluxation and when rapid mobilization has been determined to be a sufficiently important factor, an anterior cervical fusion can be done with negligible morbidity and mortality. The fusion is performed four to eight days postinjury, and the patient is allowed out of bed on the fourth postoperative day with adequate protection. If flexion and extension
films, taken
at six weeks, reveal no movement, further immobilization is discontinued. It can also be argued that all of these injuries should not be operated on when four out of five may be expected to be stable at the end of 12 weeks of conservative treatment.5 Likewise, the same rationale may be applied to the odontoid fractures described above. Results of treatment in odontoid fractures are usually expressed on the basis of bony union at the site of the fracture. In other words, a firm fibrous union without radiographic evidence of bony union and with no evidence of motion on cineradiography or flexion and extension films would be classified as a failure. Whether, in fact, it is necessary for bony union to
162
Figure
3a-Anterior subluxation C5 on C6 with residual angulation at the CS-6 interspace secondary to a
Jlexion
rotation
injury.
occur at the site of the odontoid fracture, when the ligamentous complex posteriorly and anteriorly has healed adequately to provide stability, remains to be proven. This fact probably explains, to some degree, the variance in reported statistics for conservative treatment (eg, Schatzker,22 64 to 5 per cent successful). Recent experience with the use of a halo body cast 19 in the management of cervical spine injuries may further alter these relative indications for surgical intervention. In our recent series, we fused 8 out of 15 anterior subluxations anteriorly and I of our 6 odontoid fractures posteriorly. The decision to elect surgical management for these relative indications rests first on the ability of the surgeon to perform a fusion without endangering the neurologic status of the patient, and secondly, on the rehabilitative and socioeconomic needs of the patient.
It is noteworthy that none of our extension injuries below the odontoid required fusion for late instability, confirming Cheshire’s finding. In the patient with neurologic deficit (Table IV), it is our feeling that these injuries (ie, fractures, dislocations) should all be
reduced and stabilized in traction for
a
period of seven to ten days prior to any surgical intervention unless documented progressive neurologic deficit is present. The report by Verbiest24 of two deaths associated with ear!y intervention in complete cord lesions indicates that a period
Figure 3b-Eleven months after
anterior
infusion.
of stabilization in traction is desirable. Our own experience with death following laminectomy in one patient who underwent surgical decompression within 24 hours of an incomplete cord lesion supports this concept. When a complete cord lesion is present, it should be stabilized in traction and then managed by open or closed means depending upon the classification of the injury, and its propensity for late instability as well as the individual surgeon’s preference for management. Our preference in the complete cord lesion has been initial reduction and stabilization in traction followed by an anterior interbody fusion unless locked facets are present. The use of the anterior interbody fusion allows earlier mobilization of the patient in a cervical brace for rehabilitative means.
igure
4-Flexion rotation injury at CS-6 with anterior subluxation and locked facet joints with 60 pounds of traction while attempting reduction.
In the presence of an incomplete cord lesion the patient must be evaluated carefully as to his neurologic status on admission after the institution of cervical traction and during attempts at reduction in traction to avoid increasing the neurologic injury.&dquo; Should a documented increase in neurologic deficit occur, consideration must be given to surgical intervention. However, bearing in mind the high mortality and reported increase in neurologic deficit following laminectomy, we do not recommend laminectomy as the method of decompressing partial cord lesions following cervical spine trauma. Since many of these are anterior cord syndromes,23 we prefer the anterior approach. Furthermore, with partial lesions where the neurologic deficit has remained
163
stable,
we
have
myelography
performed air or pantopaque
to determine if an
intraspinal
lesion is present. If an anterior fusion is contemplated, and no protuded disc is demonstrated, then the posterior longitudinal ligament need not be further compromised, and a simple bony fusion may be performed. A similar simplification of the operative procedure occurs if the posterior approach is used, i.e., subluxed facets, and prior knowledge exists concerning the presence of a mass lesion. Where nerve root involvement is present, a posterior approach may be indicated for foraminotomy after the acute trauma to the cord has subsided. Yet, in our experience this has been well-handled by an anterior approach where adequate reduction of the fracture and stabilization by interbody fusion has produced resolution of the nerve root injury. We feel laminectomy has a place only in the removal of foreign bodies, such as missiles or bone fragments in the spinal canal. These might best be approached from the posterior aspect of the neck. When there is a progressive neurologic deficit, either with a bursting fracture compressing the cord anteriorly or a combined fracture dislocation with extrusion of the cervical intervertebral disc into the spinal canal, anterior decompression and interbody fusion seems to offer the most reasonable approach to restoring neurologic function and, at the same time, providing good stabilization. However, once again we would like to emphasize that an initial period of stabilization with cervical traction seems to be beneficial rather than harmful. In our own experience this type of management avoids the potential mortality when early anterior fusions are done as reported by Verbiest.
CHOICE OF OPERATIVE PROCEDURE Anterior fusion or posterior fusion for an unstable vertebral element following injury to the cervical spine will provide the same long-term stability assuming fusion occurs. The choice of approach for stabilizing the cervical spine, in many instances, rests with the individual surgeon’s preference. We prefer anterior stabilization when anterior subluxations are managed operative164
Figure
5-Extensioti rnjurv at the C2 level with fracture throu4 pedicles of C2 indicating an extension injurv at’ avulsion of the anterior margin of the second vertebra where it remains attached to the anteri . longitudinal ligament between C2 and C3.
cervic
I
Figure
6-A tvpe II odontoid fracture with a fracture li extending through the base of the odontoid and i junction with the body of the second cervical vert
I
bra.
ly. In the case of a neurologic deficit, decompression and single interspace fusion may be accomplished with minimal trauma to the patient and can provide excellent early stability allowing the patient to be rapidly
Figure
TABLE III
Indications for Surgical Stabilization in Unstable Injuries without Neurologic Deficits
TABLE IV
Cervical
Spine Fractures Neurologic Defects
with
7-A tvpe III I odontoid
extending
into
fracture with the fracture the bodv of the second cervical
vertebra and carrving bilization alone.
TABLEI
a
good prognosis after immo-
Cervical
Spine
Fracture
or
Frac-
ture/Dislocation without Neuro-
logic
TABLE II
Deficit
Indications for Surgical Stabilization in Unstable Injury without Neurologic Defect
mobilized. We manage these patients in traction for the first week to ten days after surgery, and then mobilize them in a brace or halo body cast for an additional eight to ten weeks. A posterior approach is preferred for open reduction of locked facet joints to
permit full visualization of the facets and to facilitate osteotomy of the bony block, if necessary. A concomitant posterior fusion with wire stabilization from the vertebral spine and lamina above the dislocation, to the vertebral spine and lamina below the dislocation, is then carried out. These patients are then managed in a manner similar to those in which anterior fusions are performed. However, they are rarely transferred to a neck brace alone prior to six weeks postsurgery. In those flexion-compression injuries with disrupted posterior soft tissues and fractures of the body anteriorly, which have not been reduced and held in traction (Figure 8), we prefer a posterior fusion unless there is an indication for decompression of the anterior spinal canal to alleviate neurologic deficit. When no neurologic deficit is present, it is our feeling that reduction and fusion can best be achieved by using the intact posterior bony elements for wire fixation and bone grafting. A posterior approach for open reduction of locked facets is preferred to Cloward’s
165
technique8 where blind reduction is accomplished from the front and requires removal of the normal disc above the injury level. In those cases of late instability following closed treatment, theoretical advantages of posterior or anterior fusion may be proposed by advocates of either approach. We can see no clear contraindications to fusion from either the anterior or posterior approach in this circumstance. However, we favor fusing from the anterior approach when there is no gross disruption of the vertebral body, and likewise fusion posteriorly when the body is comminuted and the posterior soft tissues are disrupted with intact posterior bony elements. We feel that these criteria allow for a more secure fixation and earlier mobilization of the patient. In recent years the use of the halo body cast for protection of potentially unstable lesions has added a new dimension to our treatment of cervical spine fractures. It may well be that many of the injuries we now consider to be surgical candidates for stability alone may in the future require only immobilization in the halo body cast. At the present time, we use a halo body cast routinely on fractures of the odontoid, whether they are treated surgically or nonsurgically. In addition, the common fracture of the second cervical vertebra that occurs in extension, the so-called &dquo;hangman’s fracture&dquo; described by Cornish,’has been wellmanaged in our hands utilizing a halo body
Figure
8a-Fracture dislocation C5 on C6 treated in traction l weeks with residual anterior angulation.
cast.
For the athlete who has sustained a cervical spine injury, where neurologic function has not been compromised, the question
arises as to when a return to be expected. It is our feeling that once a stable spine has been achieved, return to previous levels of activities is not contraindicated. This implies a solid bony fusion or the absence of detectable instability on flexion and extension, confirmed in x-ray, 6 months post injury. In those injuries with relatively high rates of late instability (Type II odontoid fractures and anterior subluxations), we prefer an early surgical fusion to insure stability for the individual who plans to return to sports activities where the neck may again be in jeopardy.
frequently
sports
166
can
Figure 8b-Eight
weeks
after fusion of C4
to
C6.
SUMMARY In order to manage the patient with a cervical spine injury, one must be familiar with a diagnostic classification of these injuries and be able to apply this classification to the individual patient. When a cooperative effort is made between orthopedists and neurosurgeons, we have found that most cervical spine injuries can be managed successfully without operative means using Cheshire’s classification for predicting late instability. We have been able to identify ( I ) those patients who would not substantially benefit from surgical intervention; (2) certain types of injuries where relative indications for surgery may be considered; and (3) we have confirmed the danger and risk of early operative intervention following cervical spine trauma in the neurologically damaged spinal cord. References 1. Anderson LD, D’Alonzo RT: Fractures of the odontoid process of the axis. J Bone Joint Surg, 56-A: 1663 -1674, 1974. 2. Braakman R, Vinken PJ: Unilateral facet interlocking in the lower cervical spine. J Bone Joint Surg, 49-B: 249-257, 1967. 3. Burke DC: Hyperextension injuries of the spine. J Bone Joint Surg, 53-B: 3-12, 1971. 4. Burke DC, Berryman D: The place of closed manipulation in the management of flexionrotation dislocations of the cervical spine. J Bone Joint Surg., 53-B: 165-182, 1971. 5. Cheshire DJ: The stability of the cervical spine following the conservative treatment of fractures and fracture dislocations. Paraplegia 7: 193-203, 1969. 6. Chapman MN, Hoff JT: Skull traction for spinal cord injury. JAMA, 227: 1006, 1974. 7. Clawson DK, Gunn DR, Fry LR, Garrick J, Grainger DW, Hansen ST, Mulholland RC: Early anterior fusion for cervical spine injury. JAMA, 215: 2113, 1971. 8. Cloward RB: Reduction of traumatic dislocation of the cervical spine with locked facets. J Neurosurg, 38: 527-531, 1973. 9. Cloward RB: Skull traction for cervical spine
injury:
Should it be abandoned? JAMA, 225:
1008, 1973. 10. Cloward RB: Treatment of spinal cord injury. JAMA, 228: 1096-1097, 1974. 11. Cornish BL: Traumatic spondylolisthesis of the axis. J Bone Joint Surg, 50-B: 31-43, 1968. 12. David D, Bohlman H, Walker AE, Fisher R, Robinson R: The pathological findings in fatal craniospinal injuries. J Neurosurg, 34: 603-613, 1971. 13. Ducker TB, Lucas JT, and Perot PL: National spinal cord injury registry. Division of Neurosurgery, Medical University of South Carolina, Charleston, S.C. October, 1974. 14. Fried LC: Cervical spinal cord injury during skeletal traction. JAMA, 229: 181-183, 1974. 15. Garger WN, Fisher RB, Halfmann HW: Vertebrectomy and fusion for "teardrop fracture" of the cervical spine: Case report. J Trauma, 9: 887-893, 1969. 16. Gosch HH, Godding E, Schneider RC: An experimental study of cercical spine and cord injuries. J Trauma 12: 570-576, 1972. 17. Holdsworth FW: Fractures, dislocations, and fracture-dislocations of the spine. J Bone and Joint Surg, 45-B: 6-20, 1963. 18. Lima C, deOliveira JC: Anterior fusion for fractures and dislocations of the cervical spine. Injury, 2: 205-210, 1971. 19. Prolo DJ, Runnels JB, Jameson RM: The injured cervical spine: Immediate and longterm immobilization with the halo. JAMA, 224: 591-594, 1973. 20. Roaf R: A study of the mechanics of spinal injury. J Bone Joint Surg, 42-B: 810-823, 1960. 21. Rogers WA: Fractures and dislocations of the cervical spine. J Bone Joint Surg, 39-A:
341-376, 1957. 22. Schatzker K, Rorabelk CH, Waddell J: Fractures of the dens. J Bone Joint Surg, 53-B:
392-405, 1971. 23. Schneider RC, Kahn EA: Chronic neurological sequelae of acute trauma to the spine and spinal cord. J Bone Joint Surg, 38-A: 985-997, 1956. 24. Verbiest H: Anterolateral operations for fractures and dislocations in the middle and lower parts of the cervical spine. J Bone Joint Surg, 51-A: 1489-1530, 1969. 25. White RJ: Skull traction for spinal cord injury. JAMA, 227: 1006, 1974.
167
Neck
injuries in sports are among the dangerous the athlete faces. A recent survey of 84 cervical spine injuries&dquo; revealed that one-third of these injuries were sustained in sports activities. Fortunately, these severe injuries represent a small proportion of the injuries seen by the physician most
on sports medicine; however, the potential danger involved in these injuries and their treatment dictates an understanding of this problem for every physician caring for athletes. Significant neck injuries have been seen by the authors in athletes involved in football, basketball, gymnastics, wrestling, diving, skiing and all forms of vehicle racing. The clinician searching for an approach to cervical spine injuries is faced with conflicting views in the literature as to appropriate management.2.J.8.11.25 Recent controversy has centered around the use of anterior decompression and fusion9 1°,15,18.2’ versus traction and subsequent stabilization by
concentrating
nonoperative
means
or
posterior
fusion. 4.6.7,19 The choice of treatment in a given patient depends on the presence or absence of neurologic deficit. The neuro-
Roby C. Thompson, Jr., MD, Department of Orthopedic Surgery, University of Minnesota School of Medicine, Minneapolis, Minnesota. J.N. Morris, Jr., MD, Department of Orthopedic Surgery, University of Virginia School of Medicine, Charlottesville, Virginia. John A. Jane, MD, Department of Neurological Surgery, University of Virginia School of Medicine, Charlottesville, Virginia.
logic status of the patient must be protected and improved upon if possible. However, the treatment selected should avoid jeopardizing this status when viable alternatives are available. The type of injury present should determine the inherent stability of the cervical spine and suggest the best means for restoring stability after treatment has been terminated. In addition, consideration must be given to the rehabilitative, psychological, social and medical needs of the patient. By relating the patient’s injury to documented previous studies, appropriate treatment can be initiated which will protect his neurologic status, stabilize his injury through operative or nonoperative means and minimize his hospitalization. Holdsworth’s classification of injuries to the spine&dquo; was derived from the mechanism producing the injury. Cheshire’ modified this to relate directly to cervical spine injuries. The latter study of 257 cases of cervical spine injuries with neurologic deficit described the stability of the spine following nonoperative treatment in 212 cases. Treatment consisted of reduction of the deformity by traction or manipulation. Subsequent protection in skull traction for six to eight weeks was followed by a cervical collar or brace for a total of 12 weeks of immobilization. Assessment of stability was then made by radiographic examination of the cervical spine in flexion and extension. Using this study as a guideline, we treated 62 cervical spine injuries on the Orthopedic 159
and
Neurosurgical Services at the UniverVirginia between 1968 and 1973. Our approach was largely conservative since surgery was deemed necessary in only 17 of our sity
62
of
cases.
CLASSIFICATION OF INJURIES Classification of cervical spine injuries, according to the mechanism producing the injury, is a simple and useful way of determining treatment and prognosis. Flexion may occur with compression or rotation as secondary forces; the direction and magnitude of the force determines the extent of the injury.ls,za.l3 Flexion-compression injuries result in a simple compression fracture of the vertebral body when the
injuries
interspinous ligaments
are
not
disrupted
When the flextion force, being transmitted through the cervical spine, has a magnitude sufficient to produce disruption of the interspinous ligaments, a fracture of the vertebral body at or below the level of the disrupted posterior soft tissues may occur (Figure 1).~5 In contrast, a true vertical compression fracture produces a bursting injury of the vertebral body with the fragments of the body being displaced posteriorly and anteriorly (Figure 2).5 This fracture is uncommon in the cervical spine compared to the thoracolumbar junction and is most commonly seen in the neck with a bursting fracture of the ring of the first cervical vertebra (Jefferson’s fracture). When rotation is combined with a flexion force, facet dislocation or anterior subluxation occurs in the cervical spine (Figures 3 and 4).~ ~Extension injuries are identified by fractures of the posterior elements, avulsion of the anterior longitudinal ligament with or without a portion of the anterior body below the level of the injury. Extension injuries may sometimes involve complete posterior dislocation of a vertebral body (Figure 5).’,&dquo; Utilizing this classification of cervical spine injuries, Cheshire reported an overall incidence of instability (after 12 weeks of immobilization) of 5.4 per cent with a range from 0 to 7.3 per cent. Anterior subluxations, however, revealed an incidence of late instability of 21per cent. Odontoid fractures have been classified 160
and studied by several authors. In Cheshire’s series there were only eight atlantoaxial injuries out of 257 cases. This is a low percentage compared to most studies of cervical spine fractures.12,21 One would suspect that since all of his patients had neurologic deficit, a smaller proportion of atlantoaxial injuries reached his center, as most of these injuries either result in death or minimal neurologic defici t.22 Anderson’s classification of odontoid fractures allows prognostication of bony union as an end result based on the anatomic location of the fracture. In a retrospective study of nonoperative treatment in odontoid fractures, they found that fractures through the base of the odontoid (Figure 6) had a 37% nonunion
Figure
of the fifth cervical vertebral body with disruption of the interspinous ligaments between C5 and C6 posteriorlv. A flexion-compression injury with the inferior margin of the vertebral body above being avulsed by the vertebral body below.
I-Fraction
I
or a cervical brace was used for a minimum of 12 weeks. Thirty-seven of our 62 cases had either cord or nerve root injury, and 13 had associated head injuries. Five of the patients with neurologic deficit died. Three of the five patients had a complete cord lesion, and two of these underwent posterior decompression at two and three weeks post-injury respectively. One complete cord lesion patient died three weeks post-injury from a C5 level lesion managed with supportive care. Two of the five deaths occurred from a partial cord lesion. One of these patients died following laminectomy on the day of injury, and another elderly patient died of unknown causes three weeks after a C6-7 subluxation which had been reduced in traction and was showing progressive neurologic improvement at the time of death. None of the surviving patients showed an increase in neurologic deficit after admission to the hospital. Twenty of the 32 patients improved significantly, and seven of these underwent
cast
surgical
treatment.
DISCUSSION
Figure
2-Vertical compression fracture of sixth cervical vertebrae with compression of the vertebral bodv below by the vertebral body above and disruption of the posterior soft tissues at the CS-6 interspace. (Illustration shows patient in traction.)
rate whether
in down into the body of the second cervical vertebra (Figure 7) where only one out of 11nonunions was encountered.
displaced
or
undisplaced
contrast to fractures that extended
MATERIALS Our injuries were classified according to Cheshire’s criteria except for odontoid fractures where Anderson’s method was used. Ten percent of our cases involved odontoid fractures, 25% anterior subluxations, 8% flexion-rotation injuries with locked facets, 30% flexion-compression injuries, and 27% were extension injuries. Two of our patients had laminectomies, five had posterior fusions, and nine had anterior fusions. The remainder were treated by traction for three to six weeks, and then, either a halo body
With minor exceptions, our data support Cheshire’s findings that nonoperative treatment of most cervical spine injuries can be expected to produce a stable spine without increasing neurologic deficit. After reviewing the literature on cervical spine injuries and considering our own results, we have arrived at a scheme that allows the clinician to select a rational method to determine prognosis and a choice of therapy, in cases of cervical spine injury, best suited to the individual patient and surgeon. Our plan is to categorize the patient’s condition, first on the basis of his neurologic deficit, and second to classify the type of injury according to the method outlined above. In the patient with no detectable neurologic deficit (Table I), the neck injury may be a mild compression fracture of the vertebral body. Mechanisms of injury might have involved the presence of flexion forces, a simple sprain of the anterior longitudinal ligament, undisplaced fractures through the lamina, or lateral masses in the presence of extension forces. In these cases, sympto161
matic treatment with traction and subse-
quent protection using a cervical brace very often brings good results. If there displacement, we feel it should be
is bony reduced system protected from
and the nervous further damage by surgical or nonsurgical methods until stability of the cervical spine has been restored. In deciding on surgical versus nonsurgical methods of managing these injuries, we feel there are some absolute indications for stabilization of the cervical spine by operative methods (Table II). Under absolute indications, we include late instabilitv following closed treatment for anv injurv and flexion-rotation injuries where locked facet joints are unreduced bv closed means. In addition to these absolute indications, certain relative indications (Table III) for surgical stabilization in the neurologically normal patient would include those injuries where a relatively high incidence of late instability might be expected, such as anterior subluxations or fractures through the neck of the odontoid at its junction with the body of C2. When careful consideration is given to the patient with an anterior subluxation and when rapid mobilization has been determined to be a sufficiently important factor, an anterior cervical fusion can be done with negligible morbidity and mortality. The fusion is performed four to eight days postinjury, and the patient is allowed out of bed on the fourth postoperative day with adequate protection. If flexion and extension
films, taken
at six weeks, reveal no movement, further immobilization is discontinued. It can also be argued that all of these injuries should not be operated on when four out of five may be expected to be stable at the end of 12 weeks of conservative treatment.5 Likewise, the same rationale may be applied to the odontoid fractures described above. Results of treatment in odontoid fractures are usually expressed on the basis of bony union at the site of the fracture. In other words, a firm fibrous union without radiographic evidence of bony union and with no evidence of motion on cineradiography or flexion and extension films would be classified as a failure. Whether, in fact, it is necessary for bony union to
162
Figure
3a-Anterior subluxation C5 on C6 with residual angulation at the CS-6 interspace secondary to a
Jlexion
rotation
injury.
occur at the site of the odontoid fracture, when the ligamentous complex posteriorly and anteriorly has healed adequately to provide stability, remains to be proven. This fact probably explains, to some degree, the variance in reported statistics for conservative treatment (eg, Schatzker,22 64 to 5 per cent successful). Recent experience with the use of a halo body cast 19 in the management of cervical spine injuries may further alter these relative indications for surgical intervention. In our recent series, we fused 8 out of 15 anterior subluxations anteriorly and I of our 6 odontoid fractures posteriorly. The decision to elect surgical management for these relative indications rests first on the ability of the surgeon to perform a fusion without endangering the neurologic status of the patient, and secondly, on the rehabilitative and socioeconomic needs of the patient.
It is noteworthy that none of our extension injuries below the odontoid required fusion for late instability, confirming Cheshire’s finding. In the patient with neurologic deficit (Table IV), it is our feeling that these injuries (ie, fractures, dislocations) should all be
reduced and stabilized in traction for
a
period of seven to ten days prior to any surgical intervention unless documented progressive neurologic deficit is present. The report by Verbiest24 of two deaths associated with ear!y intervention in complete cord lesions indicates that a period
Figure 3b-Eleven months after
anterior
infusion.
of stabilization in traction is desirable. Our own experience with death following laminectomy in one patient who underwent surgical decompression within 24 hours of an incomplete cord lesion supports this concept. When a complete cord lesion is present, it should be stabilized in traction and then managed by open or closed means depending upon the classification of the injury, and its propensity for late instability as well as the individual surgeon’s preference for management. Our preference in the complete cord lesion has been initial reduction and stabilization in traction followed by an anterior interbody fusion unless locked facets are present. The use of the anterior interbody fusion allows earlier mobilization of the patient in a cervical brace for rehabilitative means.
igure
4-Flexion rotation injury at CS-6 with anterior subluxation and locked facet joints with 60 pounds of traction while attempting reduction.
In the presence of an incomplete cord lesion the patient must be evaluated carefully as to his neurologic status on admission after the institution of cervical traction and during attempts at reduction in traction to avoid increasing the neurologic injury.&dquo; Should a documented increase in neurologic deficit occur, consideration must be given to surgical intervention. However, bearing in mind the high mortality and reported increase in neurologic deficit following laminectomy, we do not recommend laminectomy as the method of decompressing partial cord lesions following cervical spine trauma. Since many of these are anterior cord syndromes,23 we prefer the anterior approach. Furthermore, with partial lesions where the neurologic deficit has remained
163
stable,
we
have
myelography
performed air or pantopaque
to determine if an
intraspinal
lesion is present. If an anterior fusion is contemplated, and no protuded disc is demonstrated, then the posterior longitudinal ligament need not be further compromised, and a simple bony fusion may be performed. A similar simplification of the operative procedure occurs if the posterior approach is used, i.e., subluxed facets, and prior knowledge exists concerning the presence of a mass lesion. Where nerve root involvement is present, a posterior approach may be indicated for foraminotomy after the acute trauma to the cord has subsided. Yet, in our experience this has been well-handled by an anterior approach where adequate reduction of the fracture and stabilization by interbody fusion has produced resolution of the nerve root injury. We feel laminectomy has a place only in the removal of foreign bodies, such as missiles or bone fragments in the spinal canal. These might best be approached from the posterior aspect of the neck. When there is a progressive neurologic deficit, either with a bursting fracture compressing the cord anteriorly or a combined fracture dislocation with extrusion of the cervical intervertebral disc into the spinal canal, anterior decompression and interbody fusion seems to offer the most reasonable approach to restoring neurologic function and, at the same time, providing good stabilization. However, once again we would like to emphasize that an initial period of stabilization with cervical traction seems to be beneficial rather than harmful. In our own experience this type of management avoids the potential mortality when early anterior fusions are done as reported by Verbiest.
CHOICE OF OPERATIVE PROCEDURE Anterior fusion or posterior fusion for an unstable vertebral element following injury to the cervical spine will provide the same long-term stability assuming fusion occurs. The choice of approach for stabilizing the cervical spine, in many instances, rests with the individual surgeon’s preference. We prefer anterior stabilization when anterior subluxations are managed operative164
Figure
5-Extensioti rnjurv at the C2 level with fracture throu4 pedicles of C2 indicating an extension injurv at’ avulsion of the anterior margin of the second vertebra where it remains attached to the anteri . longitudinal ligament between C2 and C3.
cervic
I
Figure
6-A tvpe II odontoid fracture with a fracture li extending through the base of the odontoid and i junction with the body of the second cervical vert
I
bra.
ly. In the case of a neurologic deficit, decompression and single interspace fusion may be accomplished with minimal trauma to the patient and can provide excellent early stability allowing the patient to be rapidly
Figure
TABLE III
Indications for Surgical Stabilization in Unstable Injuries without Neurologic Deficits
TABLE IV
Cervical
Spine Fractures Neurologic Defects
with
7-A tvpe III I odontoid
extending
into
fracture with the fracture the bodv of the second cervical
vertebra and carrving bilization alone.
TABLEI
a
good prognosis after immo-
Cervical
Spine
Fracture
or
Frac-
ture/Dislocation without Neuro-
logic
TABLE II
Deficit
Indications for Surgical Stabilization in Unstable Injury without Neurologic Defect
mobilized. We manage these patients in traction for the first week to ten days after surgery, and then mobilize them in a brace or halo body cast for an additional eight to ten weeks. A posterior approach is preferred for open reduction of locked facet joints to
permit full visualization of the facets and to facilitate osteotomy of the bony block, if necessary. A concomitant posterior fusion with wire stabilization from the vertebral spine and lamina above the dislocation, to the vertebral spine and lamina below the dislocation, is then carried out. These patients are then managed in a manner similar to those in which anterior fusions are performed. However, they are rarely transferred to a neck brace alone prior to six weeks postsurgery. In those flexion-compression injuries with disrupted posterior soft tissues and fractures of the body anteriorly, which have not been reduced and held in traction (Figure 8), we prefer a posterior fusion unless there is an indication for decompression of the anterior spinal canal to alleviate neurologic deficit. When no neurologic deficit is present, it is our feeling that reduction and fusion can best be achieved by using the intact posterior bony elements for wire fixation and bone grafting. A posterior approach for open reduction of locked facets is preferred to Cloward’s
165
technique8 where blind reduction is accomplished from the front and requires removal of the normal disc above the injury level. In those cases of late instability following closed treatment, theoretical advantages of posterior or anterior fusion may be proposed by advocates of either approach. We can see no clear contraindications to fusion from either the anterior or posterior approach in this circumstance. However, we favor fusing from the anterior approach when there is no gross disruption of the vertebral body, and likewise fusion posteriorly when the body is comminuted and the posterior soft tissues are disrupted with intact posterior bony elements. We feel that these criteria allow for a more secure fixation and earlier mobilization of the patient. In recent years the use of the halo body cast for protection of potentially unstable lesions has added a new dimension to our treatment of cervical spine fractures. It may well be that many of the injuries we now consider to be surgical candidates for stability alone may in the future require only immobilization in the halo body cast. At the present time, we use a halo body cast routinely on fractures of the odontoid, whether they are treated surgically or nonsurgically. In addition, the common fracture of the second cervical vertebra that occurs in extension, the so-called &dquo;hangman’s fracture&dquo; described by Cornish,’has been wellmanaged in our hands utilizing a halo body
Figure
8a-Fracture dislocation C5 on C6 treated in traction l weeks with residual anterior angulation.
cast.
For the athlete who has sustained a cervical spine injury, where neurologic function has not been compromised, the question
arises as to when a return to be expected. It is our feeling that once a stable spine has been achieved, return to previous levels of activities is not contraindicated. This implies a solid bony fusion or the absence of detectable instability on flexion and extension, confirmed in x-ray, 6 months post injury. In those injuries with relatively high rates of late instability (Type II odontoid fractures and anterior subluxations), we prefer an early surgical fusion to insure stability for the individual who plans to return to sports activities where the neck may again be in jeopardy.
frequently
sports
166
can
Figure 8b-Eight
weeks
after fusion of C4
to
C6.
SUMMARY In order to manage the patient with a cervical spine injury, one must be familiar with a diagnostic classification of these injuries and be able to apply this classification to the individual patient. When a cooperative effort is made between orthopedists and neurosurgeons, we have found that most cervical spine injuries can be managed successfully without operative means using Cheshire’s classification for predicting late instability. We have been able to identify ( I ) those patients who would not substantially benefit from surgical intervention; (2) certain types of injuries where relative indications for surgery may be considered; and (3) we have confirmed the danger and risk of early operative intervention following cervical spine trauma in the neurologically damaged spinal cord. References 1. Anderson LD, D’Alonzo RT: Fractures of the odontoid process of the axis. J Bone Joint Surg, 56-A: 1663 -1674, 1974. 2. Braakman R, Vinken PJ: Unilateral facet interlocking in the lower cervical spine. J Bone Joint Surg, 49-B: 249-257, 1967. 3. Burke DC: Hyperextension injuries of the spine. J Bone Joint Surg, 53-B: 3-12, 1971. 4. Burke DC, Berryman D: The place of closed manipulation in the management of flexionrotation dislocations of the cervical spine. J Bone Joint Surg., 53-B: 165-182, 1971. 5. Cheshire DJ: The stability of the cervical spine following the conservative treatment of fractures and fracture dislocations. Paraplegia 7: 193-203, 1969. 6. Chapman MN, Hoff JT: Skull traction for spinal cord injury. JAMA, 227: 1006, 1974. 7. Clawson DK, Gunn DR, Fry LR, Garrick J, Grainger DW, Hansen ST, Mulholland RC: Early anterior fusion for cervical spine injury. JAMA, 215: 2113, 1971. 8. Cloward RB: Reduction of traumatic dislocation of the cervical spine with locked facets. J Neurosurg, 38: 527-531, 1973. 9. Cloward RB: Skull traction for cervical spine
injury:
Should it be abandoned? JAMA, 225:
1008, 1973. 10. Cloward RB: Treatment of spinal cord injury. JAMA, 228: 1096-1097, 1974. 11. Cornish BL: Traumatic spondylolisthesis of the axis. J Bone Joint Surg, 50-B: 31-43, 1968. 12. David D, Bohlman H, Walker AE, Fisher R, Robinson R: The pathological findings in fatal craniospinal injuries. J Neurosurg, 34: 603-613, 1971. 13. Ducker TB, Lucas JT, and Perot PL: National spinal cord injury registry. Division of Neurosurgery, Medical University of South Carolina, Charleston, S.C. October, 1974. 14. Fried LC: Cervical spinal cord injury during skeletal traction. JAMA, 229: 181-183, 1974. 15. Garger WN, Fisher RB, Halfmann HW: Vertebrectomy and fusion for "teardrop fracture" of the cervical spine: Case report. J Trauma, 9: 887-893, 1969. 16. Gosch HH, Godding E, Schneider RC: An experimental study of cercical spine and cord injuries. J Trauma 12: 570-576, 1972. 17. Holdsworth FW: Fractures, dislocations, and fracture-dislocations of the spine. J Bone and Joint Surg, 45-B: 6-20, 1963. 18. Lima C, deOliveira JC: Anterior fusion for fractures and dislocations of the cervical spine. Injury, 2: 205-210, 1971. 19. Prolo DJ, Runnels JB, Jameson RM: The injured cervical spine: Immediate and longterm immobilization with the halo. JAMA, 224: 591-594, 1973. 20. Roaf R: A study of the mechanics of spinal injury. J Bone Joint Surg, 42-B: 810-823, 1960. 21. Rogers WA: Fractures and dislocations of the cervical spine. J Bone Joint Surg, 39-A:
341-376, 1957. 22. Schatzker K, Rorabelk CH, Waddell J: Fractures of the dens. J Bone Joint Surg, 53-B:
392-405, 1971. 23. Schneider RC, Kahn EA: Chronic neurological sequelae of acute trauma to the spine and spinal cord. J Bone Joint Surg, 38-A: 985-997, 1956. 24. Verbiest H: Anterolateral operations for fractures and dislocations in the middle and lower parts of the cervical spine. J Bone Joint Surg, 51-A: 1489-1530, 1969. 25. White RJ: Skull traction for spinal cord injury. JAMA, 227: 1006, 1974.
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