ORIGINAL C O N T R I B U T I O N
cervical spine immobilization orthosis
Emergency Cervical-Spine Immobilization From the Regional Spinal Cord Injury Care System of Southern California, Rancho Los Amigos Medical Center, Downey, California;t and the Department of Orthopaedic Surgery, University of Southern California, Los Angeles. *
David R Chandler, MD* Charles Nernejc Rodney H Adkins, PhDt Robert L Waters, MD *t
Received for publication November 20, 1990. Revisions received March 19, 1991, and January 3, 1992. Accepted for publication January 29, 1992. Presented in part at the American Spinal Injury Association Annual Meeting in Las Vegas, Nevada, April 1990. This research was supported in part by the National Institute for Disability and Rehabilitation Research Grant No. G008535134.
Study objective: To determine the effectiveness of a cervicalspine immobilization using a rigid cervical extrication collar and an Ammerman halo orthosis with and without spine boards. Design: A mixed model multivariate design with one within factor (device type) and one between factor (spine board application). Setting: Radiology suite. Type of p a r t i c i p a n t s : Twenty normal men with a mean age of 29.6.
Interventions: Unrestrained cervical motion was compared with motion in a cervical extrication collar and an Ammerman halo orthosis with and without a spine board. Measurements: Photographic measurement of head and neck motion during maximal flexion-extension, lateral bending, and rotation. Radiologic measurement of maximal intervertebral flexion-extension. Main results: Both cervical extrication collar and Ammerman halo orthosis significantly reduced motion in all planes (P< .001) with the Ammerman halo orthosis reducing these motions significantly more (P< .001). With the use of a spine board these motions were restricted even more (P< .001). The Ammerman halo orthosis with a spine board provided the greatest immobilization, equivalent to that provided by an halo-vest. ConclUsion: A rigid cervical collar and a spine board provide significantly better immobilization than the collar alone. Further immobilization is provided by an Ammerman halo orthosis. [Chandler DR, Nemejc C, Adkins RH, Waters RL: Emergency cervicalspine immobilization. Ann EmergMed October 1992;21:1185-1188.]
OCTOBER1992 21:10 ANNALSOF EMERGENCYMEDIClNE
1185/1£
IMMOBILIZATION Chandler et al
INTRODUCTION
In accidents severe enough to require the vehicle to be towed, 33% of passengers will sustain a severe neck injury, and if the passenger is ejected from the vehicle, the risk increases to 71%. 1 Severe neck injuries were defined as those with an A b b r e v i a t e d I n j u r y Scale (AIS) 3, 4, 5, or 6. These include fractures and/or dislocations at or below C4 with or without nerve root damage, or with spinal cord damage, and fractures and/or dislocations at or above C3 with cord damage. Thirty-nine percent of cervical-spine fractures have associated neurologic damage; if the fracture involves the verteb r a l body and the posterior spinal elements with misalignment of the vertebral column, the association with neurologic damage increases to 70%. 2 Unfortunately, a significant numb e r of the associated neurologic injuries are thought to occur or to be aggravated during emergency extrication, t r a n s p o r t , and evaluation of the patient. 3 The s t a n d a r d method of immobilizing the cervical spine in the prehospital setting is the use of a cervical collar in combination with a spine b o a r d , sandbags, and tape. 4 The purpose of this study was to evaluate the effectiveness of a new device, the Ammerman halo orthosis (Ammerman Trauma Systems, Pacific Pahsades, California), that allows secure, noninvasive immobilization of the skull, in comparison with a conventional cervical extrication collar. MATERIALS
AND
METHODS
Twenty volunteers with clinically and radiographically normal cervical spines were tested. All were men, 19 white and one black, with an average age of 29.8 + 4.0 years, average height of 177 _+5.5 cm, and average weight of 77.7 + 9.6 kg. The Ammerman halo orthosis is made of radiolucent Lexan ® (Figure). The cranium rests in a p a d d e d rigid posterior convex shell, and the head is firmly secured in the posterior shell by an adjustable, p a d d e d head band. Caudal support
Figure. Cervical extrication collar is depicted on left; Ammerman halo orthosis is depcted on right.
2 0 / 1 1 86
is achieved by pads that contact the chest anteriorly at or beneath the clavicles and posteriorly over the trapezius muscles. A traction mechanism allows adjustment for different neck lengths, allowing one size to fit all. The anterior neck is left completely unrestricted, allowing access to the cricothyroid membrane and central venous system. In addition, there is nothing restricting the chin, thereby allowing easy airway management and protection from potential aspiration. Clamps on the Ammerman halo orthosis enable rigid attachment to a spine b o a r d , alleviating the necessity of cumbersome sandbags and tape. The cervical extrication collar used was a Stifneck ® collar (California Medical Products, Long Beach, California) (Figure) that provides the best immobilization of conventional field collars. 5 It has a low-reaching chest p a d that provides contact with the sternum to restrict flexion-extension. It has an anterior opening for access to the cricothyroid membrane and is made of radiolucent material. It is adjustable with Velcro ® straps and is manufactured in five sizes. Additional immobilization with a spine b o a r d is recommended when using a cervical extrication collar during extrication of accident victims with suspected neck injuries or other major trauma. Therefore, in the testing procedures outhned below, the effectiveness of the Ammerman halo orthosis and cervical extrication collar was determined with and without a spine b o a r d . Baseline d a t a regarding rest position and the total range of motion without immobilization were determined for each subject by photographic and radiographic measures in the seated position. Subjects were asked to perform maximum cervical extension, flexion, lateral bending, and rotation while seated in a high-backed rigid chair. The principal investigator was present throughout the radiographic and photographic examinations to ensure that the subject's posterior thorax remained in contact with the chair back, thereby preventing thoracic spine motion. Photographs were taken in the rest position and at the end point of each maximal range of motion. Markers attached to the subjects' heads facilitated measurement on the photographs of range of motion. Radiographic measurement of flexion-extension at each i n t e r v e r t e b r a l level was performed according to the method described by Johnson et al, 6 in which the angular displacements are measured from lines drawn through the inferior end-plate of each vertebra. Next, to minimize radiation exposure, the patients were divided into two equal groups. In ten subjects, the range of motion was measured photographically and radiographically in the Ammerman halo orthosis and cervical extrication collar alone. In the other ten subjects, the range of motion was determined photographically and radiographically with the cervical extrication collar in place and the head taped to a supine spine b o a r d , and also with the Ammerman halo orthosis attached to a supine spine b o a r d . Each subject had nine lateral radiographs, with a total radiation dosage of 1.17 rads.
ANNALS OF EMERGENCYMEDICINE 21:10 OCTOBER 1992
IMMOBILIZATION Chandler et al
RESULTS
DISCUSSION
In unrestricted subjects, the photographically determined ranges of motion for the cervical spine were as follows: flexion-extension, 125 + 7.7 degrees; lateral bending, 77.4 + 4.9 degrees; and rotation, 136 + 7.1 degrees. The effectiveness of the various interventions was expressed as a percentage of unrestricted motion. The total flexion-extension range of motion of a subject with either device and with or without spine board was compared to that same subject's unrestricted flexion-extension. Thus, each subject served as his own control. The best immobilization was provided by an Ammerman halo orthosis used with a spine board. The least restriction of motion was provided by the cervical extrication collar alone. There was no significant difference in the amount of motion between the Ammerman halo orthosis without a spine board and the cervical extrication collar with a spine board. There was significantly less motion in the Ammerman halo orthosis alone than in the cervical extrication collar alone. There was also significantly less motion with a spine board than without a spine board (P < .001). The board had a greater effect reducing motion when used with the cervical extrication collar than with the Ammerman halo orthosis (P < .002), but the Ammerman halo orthosis had less available motion to be affected by addition of the spine board. These analyses are summarized (Table 1). The radiographic analysis of flexion-extension measured from occiput to C7 demonstrated similar results to the photographic flexion-extension data. For analysis of radiographic data, the effectiveness of the various interventions was expressed as the absolute degrees of motion measured at each intervertebral motion segment and from the occiput to C7. Significant differences in immobilization were demonstrated between the devices (P < .006) and by the addition of a board to the cervical extrication collar (P < .04) but not to the Ammerman halo orthosis. Significant differences were found between devices without the board for overall flexion-extension (P < .01) and at each intervertebral level (P < .0001). Significant differences also were demonstrated between the devices with the spine board for overall flexion-extension (P < .001) and at each level (P < .001). The means of intervertebral motion during flexion-extension at the different vertebral levels are summarized (Table 2).
The effectiveness of cervical immobilization devices has been quantitatively evaluated in live subjects with goniometric studies, 7,8 plain radiographic studies, 9 combined goniometric and plain radiographic studies, 6-1° and cineradiographic studies. 11,12 Johnson et a] 6 demonstrated that the halo-vest provided the best external cervical immobilization; however, its use in the prehospital setting is not appropriate. Overestimates of cervical motion by photographic methods result from uncontrolled motion of the upper thoracic spine. Our subjects were u n d e r direct observation by the principal investigator to ensure that no thoracic motion occurred. The mean flexion-extension range determined photographically exceeded that measured radiographically by 22 degrees. However, because presence of shoulder musculature does not allow adequate visualization of the C7-T1 motion segment in standard lateral cervical radiographs, our radiographic measurements did not include motion at this segment. If allowance for a 10- to 15-degree flexion arc at C7-T1 is included, there is less than a 10-degree discrepancy between the two methods. Using photographic methods, Podolsky et al a found that taping the head to a spine board with sandbag support allowed 15 degrees of flexion-extension. The addition of a Philadelphia collar further restricted flexion-extension to 7 degrees. 8 We found an average of 14% of unrestricted flexion-extension using a cervical extrication collar with the head taped to a spine board compared with 19% of unrestricted motion using the Ammerman halo orthosis without a spine board. When we attached the Ammerman halo orthosis to a spine board, allowed motion was 5% flexion-extension, 3% lateral bending, and 3% rotation. This motion in the Ammerman halo orthosis with a spine board approximates the 4% flexion-extension, 4% lateral bending, and 1% rotation allowed in the halo-vest. 6 The radiographically determined range of flexion-extension at the intervertebral segments in our normal subjects after application of the cervical extrication collar was comparable with the motion reported by both Fisher et aU ° and
Table 1. Percentage immobilization and photographic data
Level
Percentage of Unrestricted Motion Flexion-Extension Lateral Bending Rotation Cervical extrication collar +board Ammerman halo orthosis + board
42.6+5.3 14.0 ±2.6 19.3 ± 5.5 5.2 ±0.9
51.8±10.6 15.6±3.4 17.6 ± 4.9 3.1 ± 0.9
51.6+11.0 11.6±4.0 9.5 ±4.2 3.2 ± 1.0
Means+ 95% confidencelimits; expressedas a percentageof unrestricted motion.
OCTOBER1992 21:10 ANNALS OF EMERGENCYMEDICINE
Table 2. Flexion-extension and radiographic data (degrees)*
0-1 1-2 2-3 3-4 4-5 5-6 6-7 Overall
None 14±3.2 10±2.8 12±1.6 15±2.0 18±2.0 18±2.4 16±2.3 102±7.3
Cervical Ammerman Cervical Extrication Ammerman Halo Extrication Collar Halo Orthosis Collar + Board Orthosis + Board 5±2.0 4±2.5 4±1.5 8±2.0 9±1.7 11±2.1 10±3.1 35±9.7
5±2.5 6±3.2 6±2.9 4±2.1 4±1.5 3±2.4 4±2.7 20±5.4
3±1.3 5±2.1 3±1.2 5±1,3 5±1,9 3±1,5 3±1,1 9±4,7
4±1.6 3±1,9 2±1.1 3±1.5 3±1.2 3±1.4 3±0.9 8±3.2
*Moans _+95% confidencelimits.
1187/21
IMMOBILIZATION C h a n d l e r et al
Johnson et al 6 after applying a Philadelphia collar and using similar measurement techniques. The cervical extrication collar, combined with taping the head to a spine b o a r d , permitted an average of 20 degrees of motion between the occiput and C7 in comparison with 35 degrees with the cervical extrication collar alone. The Ammerman halo orthosis with or without the spine b o a r d provided enhanced restriction, averaging 11 degrees less than the cervical extrication collar with the head taped to the spine b o a r d . CONCLUSION
The Ammerman halo orthosis examined in this study provides immobilization equivalent to a cervical extrication collar with the head taped to a spine b o a r d . When combined with a spine b o a r d , the Ammerman halo orthosis provides tempor a r y immobilization comparable with a halo-vest without the necessity of cranial pins. Our data indicate that use of the Ammerman halo orthosis allows more r a p i d immobilization of cervical-spine injuries in the prehospital setting. Using the Ammerman halo orthosis as a p r o t o t y p e , further refinement of immobilization devices should be undertaken to minimize the morbidity of suspected neck injuries.
REFERENCES 1. Huelke DF, O'Day J, Mendelsohn RA: Cervical injuries suffered in automobile crashes. J Neurosurg 1981;54:316-322. 2. Riggins RS, Kraus JF: The risk of neurologic damage with fractures of the vertebrae. J Trauma 1977;17:126-133. 3. Cloward RB: Acute cervical spine injuries. Clin Syrup 1980;32:15, 4. American Academy of Orthopaedic Surgeons: Emergency Care and Transportation of the Sick and Injured, ed 3. Menasha, Washington, AAOS, 1981. 5. Dick T, Land R: Spinal immobilization devices. J Emerg Med Serv 1982;7:26-32. 6. Johnson RM, Hart DL, Simmons EF, et al: Cervical erthoses. J Bone JointSurg 1977;59A:332-339. 7. Kaufman WA, Lunsford TR, Lunsford BR, et al: Comparison of three prefabricated cervical collars. OrthotProethetl986;39:21-28. 8. Pedolsky S, Baraff LJ, Simon RR, et al: Efficacy of cervical spine immobilization methods. J Trauma 1983;23:461-465. 9. McCabe JB, Nolan DJ: Comparison of the effectiveness of different cervical immobilization collars. Ann Emerg Med 1986;15:50-53. 10. Fisher SV, Bowar JF, Awad EA, et al: Cervical orthoses effect on cervical spine motion: Roentgenographic and goniometric method of study. Arch Phys Med Rehab 1977;58:109-115.
11, Hartman JT, Palumbo F, Hill BJ: Cineradiegraphy of the braced normal cervica{ spine. Clin Orthop 1975;189:97-182. 12. Jones MD: Cineradiographic studies of the collar-immobilized cervical spine. J Neurosurg 1960;17:633-637. Address for reprints: Robert L Waters, MD 7601 East Imperial Highway HB 117 Downey, California 90242
22/ 1188
ANNALS OF EMERGENCY MEDICINE
21:10
OCTOBER 1992
cervical spine immobilization orthosis
Emergency Cervical-Spine Immobilization From the Regional Spinal Cord Injury Care System of Southern California, Rancho Los Amigos Medical Center, Downey, California;t and the Department of Orthopaedic Surgery, University of Southern California, Los Angeles. *
David R Chandler, MD* Charles Nernejc Rodney H Adkins, PhDt Robert L Waters, MD *t
Received for publication November 20, 1990. Revisions received March 19, 1991, and January 3, 1992. Accepted for publication January 29, 1992. Presented in part at the American Spinal Injury Association Annual Meeting in Las Vegas, Nevada, April 1990. This research was supported in part by the National Institute for Disability and Rehabilitation Research Grant No. G008535134.
Study objective: To determine the effectiveness of a cervicalspine immobilization using a rigid cervical extrication collar and an Ammerman halo orthosis with and without spine boards. Design: A mixed model multivariate design with one within factor (device type) and one between factor (spine board application). Setting: Radiology suite. Type of p a r t i c i p a n t s : Twenty normal men with a mean age of 29.6.
Interventions: Unrestrained cervical motion was compared with motion in a cervical extrication collar and an Ammerman halo orthosis with and without a spine board. Measurements: Photographic measurement of head and neck motion during maximal flexion-extension, lateral bending, and rotation. Radiologic measurement of maximal intervertebral flexion-extension. Main results: Both cervical extrication collar and Ammerman halo orthosis significantly reduced motion in all planes (P< .001) with the Ammerman halo orthosis reducing these motions significantly more (P< .001). With the use of a spine board these motions were restricted even more (P< .001). The Ammerman halo orthosis with a spine board provided the greatest immobilization, equivalent to that provided by an halo-vest. ConclUsion: A rigid cervical collar and a spine board provide significantly better immobilization than the collar alone. Further immobilization is provided by an Ammerman halo orthosis. [Chandler DR, Nemejc C, Adkins RH, Waters RL: Emergency cervicalspine immobilization. Ann EmergMed October 1992;21:1185-1188.]
OCTOBER1992 21:10 ANNALSOF EMERGENCYMEDIClNE
1185/1£
IMMOBILIZATION Chandler et al
INTRODUCTION
In accidents severe enough to require the vehicle to be towed, 33% of passengers will sustain a severe neck injury, and if the passenger is ejected from the vehicle, the risk increases to 71%. 1 Severe neck injuries were defined as those with an A b b r e v i a t e d I n j u r y Scale (AIS) 3, 4, 5, or 6. These include fractures and/or dislocations at or below C4 with or without nerve root damage, or with spinal cord damage, and fractures and/or dislocations at or above C3 with cord damage. Thirty-nine percent of cervical-spine fractures have associated neurologic damage; if the fracture involves the verteb r a l body and the posterior spinal elements with misalignment of the vertebral column, the association with neurologic damage increases to 70%. 2 Unfortunately, a significant numb e r of the associated neurologic injuries are thought to occur or to be aggravated during emergency extrication, t r a n s p o r t , and evaluation of the patient. 3 The s t a n d a r d method of immobilizing the cervical spine in the prehospital setting is the use of a cervical collar in combination with a spine b o a r d , sandbags, and tape. 4 The purpose of this study was to evaluate the effectiveness of a new device, the Ammerman halo orthosis (Ammerman Trauma Systems, Pacific Pahsades, California), that allows secure, noninvasive immobilization of the skull, in comparison with a conventional cervical extrication collar. MATERIALS
AND
METHODS
Twenty volunteers with clinically and radiographically normal cervical spines were tested. All were men, 19 white and one black, with an average age of 29.8 + 4.0 years, average height of 177 _+5.5 cm, and average weight of 77.7 + 9.6 kg. The Ammerman halo orthosis is made of radiolucent Lexan ® (Figure). The cranium rests in a p a d d e d rigid posterior convex shell, and the head is firmly secured in the posterior shell by an adjustable, p a d d e d head band. Caudal support
Figure. Cervical extrication collar is depicted on left; Ammerman halo orthosis is depcted on right.
2 0 / 1 1 86
is achieved by pads that contact the chest anteriorly at or beneath the clavicles and posteriorly over the trapezius muscles. A traction mechanism allows adjustment for different neck lengths, allowing one size to fit all. The anterior neck is left completely unrestricted, allowing access to the cricothyroid membrane and central venous system. In addition, there is nothing restricting the chin, thereby allowing easy airway management and protection from potential aspiration. Clamps on the Ammerman halo orthosis enable rigid attachment to a spine b o a r d , alleviating the necessity of cumbersome sandbags and tape. The cervical extrication collar used was a Stifneck ® collar (California Medical Products, Long Beach, California) (Figure) that provides the best immobilization of conventional field collars. 5 It has a low-reaching chest p a d that provides contact with the sternum to restrict flexion-extension. It has an anterior opening for access to the cricothyroid membrane and is made of radiolucent material. It is adjustable with Velcro ® straps and is manufactured in five sizes. Additional immobilization with a spine b o a r d is recommended when using a cervical extrication collar during extrication of accident victims with suspected neck injuries or other major trauma. Therefore, in the testing procedures outhned below, the effectiveness of the Ammerman halo orthosis and cervical extrication collar was determined with and without a spine b o a r d . Baseline d a t a regarding rest position and the total range of motion without immobilization were determined for each subject by photographic and radiographic measures in the seated position. Subjects were asked to perform maximum cervical extension, flexion, lateral bending, and rotation while seated in a high-backed rigid chair. The principal investigator was present throughout the radiographic and photographic examinations to ensure that the subject's posterior thorax remained in contact with the chair back, thereby preventing thoracic spine motion. Photographs were taken in the rest position and at the end point of each maximal range of motion. Markers attached to the subjects' heads facilitated measurement on the photographs of range of motion. Radiographic measurement of flexion-extension at each i n t e r v e r t e b r a l level was performed according to the method described by Johnson et al, 6 in which the angular displacements are measured from lines drawn through the inferior end-plate of each vertebra. Next, to minimize radiation exposure, the patients were divided into two equal groups. In ten subjects, the range of motion was measured photographically and radiographically in the Ammerman halo orthosis and cervical extrication collar alone. In the other ten subjects, the range of motion was determined photographically and radiographically with the cervical extrication collar in place and the head taped to a supine spine b o a r d , and also with the Ammerman halo orthosis attached to a supine spine b o a r d . Each subject had nine lateral radiographs, with a total radiation dosage of 1.17 rads.
ANNALS OF EMERGENCYMEDICINE 21:10 OCTOBER 1992
IMMOBILIZATION Chandler et al
RESULTS
DISCUSSION
In unrestricted subjects, the photographically determined ranges of motion for the cervical spine were as follows: flexion-extension, 125 + 7.7 degrees; lateral bending, 77.4 + 4.9 degrees; and rotation, 136 + 7.1 degrees. The effectiveness of the various interventions was expressed as a percentage of unrestricted motion. The total flexion-extension range of motion of a subject with either device and with or without spine board was compared to that same subject's unrestricted flexion-extension. Thus, each subject served as his own control. The best immobilization was provided by an Ammerman halo orthosis used with a spine board. The least restriction of motion was provided by the cervical extrication collar alone. There was no significant difference in the amount of motion between the Ammerman halo orthosis without a spine board and the cervical extrication collar with a spine board. There was significantly less motion in the Ammerman halo orthosis alone than in the cervical extrication collar alone. There was also significantly less motion with a spine board than without a spine board (P < .001). The board had a greater effect reducing motion when used with the cervical extrication collar than with the Ammerman halo orthosis (P < .002), but the Ammerman halo orthosis had less available motion to be affected by addition of the spine board. These analyses are summarized (Table 1). The radiographic analysis of flexion-extension measured from occiput to C7 demonstrated similar results to the photographic flexion-extension data. For analysis of radiographic data, the effectiveness of the various interventions was expressed as the absolute degrees of motion measured at each intervertebral motion segment and from the occiput to C7. Significant differences in immobilization were demonstrated between the devices (P < .006) and by the addition of a board to the cervical extrication collar (P < .04) but not to the Ammerman halo orthosis. Significant differences were found between devices without the board for overall flexion-extension (P < .01) and at each intervertebral level (P < .0001). Significant differences also were demonstrated between the devices with the spine board for overall flexion-extension (P < .001) and at each level (P < .001). The means of intervertebral motion during flexion-extension at the different vertebral levels are summarized (Table 2).
The effectiveness of cervical immobilization devices has been quantitatively evaluated in live subjects with goniometric studies, 7,8 plain radiographic studies, 9 combined goniometric and plain radiographic studies, 6-1° and cineradiographic studies. 11,12 Johnson et a] 6 demonstrated that the halo-vest provided the best external cervical immobilization; however, its use in the prehospital setting is not appropriate. Overestimates of cervical motion by photographic methods result from uncontrolled motion of the upper thoracic spine. Our subjects were u n d e r direct observation by the principal investigator to ensure that no thoracic motion occurred. The mean flexion-extension range determined photographically exceeded that measured radiographically by 22 degrees. However, because presence of shoulder musculature does not allow adequate visualization of the C7-T1 motion segment in standard lateral cervical radiographs, our radiographic measurements did not include motion at this segment. If allowance for a 10- to 15-degree flexion arc at C7-T1 is included, there is less than a 10-degree discrepancy between the two methods. Using photographic methods, Podolsky et al a found that taping the head to a spine board with sandbag support allowed 15 degrees of flexion-extension. The addition of a Philadelphia collar further restricted flexion-extension to 7 degrees. 8 We found an average of 14% of unrestricted flexion-extension using a cervical extrication collar with the head taped to a spine board compared with 19% of unrestricted motion using the Ammerman halo orthosis without a spine board. When we attached the Ammerman halo orthosis to a spine board, allowed motion was 5% flexion-extension, 3% lateral bending, and 3% rotation. This motion in the Ammerman halo orthosis with a spine board approximates the 4% flexion-extension, 4% lateral bending, and 1% rotation allowed in the halo-vest. 6 The radiographically determined range of flexion-extension at the intervertebral segments in our normal subjects after application of the cervical extrication collar was comparable with the motion reported by both Fisher et aU ° and
Table 1. Percentage immobilization and photographic data
Level
Percentage of Unrestricted Motion Flexion-Extension Lateral Bending Rotation Cervical extrication collar +board Ammerman halo orthosis + board
42.6+5.3 14.0 ±2.6 19.3 ± 5.5 5.2 ±0.9
51.8±10.6 15.6±3.4 17.6 ± 4.9 3.1 ± 0.9
51.6+11.0 11.6±4.0 9.5 ±4.2 3.2 ± 1.0
Means+ 95% confidencelimits; expressedas a percentageof unrestricted motion.
OCTOBER1992 21:10 ANNALS OF EMERGENCYMEDICINE
Table 2. Flexion-extension and radiographic data (degrees)*
0-1 1-2 2-3 3-4 4-5 5-6 6-7 Overall
None 14±3.2 10±2.8 12±1.6 15±2.0 18±2.0 18±2.4 16±2.3 102±7.3
Cervical Ammerman Cervical Extrication Ammerman Halo Extrication Collar Halo Orthosis Collar + Board Orthosis + Board 5±2.0 4±2.5 4±1.5 8±2.0 9±1.7 11±2.1 10±3.1 35±9.7
5±2.5 6±3.2 6±2.9 4±2.1 4±1.5 3±2.4 4±2.7 20±5.4
3±1.3 5±2.1 3±1.2 5±1,3 5±1,9 3±1,5 3±1,1 9±4,7
4±1.6 3±1,9 2±1.1 3±1.5 3±1.2 3±1.4 3±0.9 8±3.2
*Moans _+95% confidencelimits.
1187/21
IMMOBILIZATION C h a n d l e r et al
Johnson et al 6 after applying a Philadelphia collar and using similar measurement techniques. The cervical extrication collar, combined with taping the head to a spine b o a r d , permitted an average of 20 degrees of motion between the occiput and C7 in comparison with 35 degrees with the cervical extrication collar alone. The Ammerman halo orthosis with or without the spine b o a r d provided enhanced restriction, averaging 11 degrees less than the cervical extrication collar with the head taped to the spine b o a r d . CONCLUSION
The Ammerman halo orthosis examined in this study provides immobilization equivalent to a cervical extrication collar with the head taped to a spine b o a r d . When combined with a spine b o a r d , the Ammerman halo orthosis provides tempor a r y immobilization comparable with a halo-vest without the necessity of cranial pins. Our data indicate that use of the Ammerman halo orthosis allows more r a p i d immobilization of cervical-spine injuries in the prehospital setting. Using the Ammerman halo orthosis as a p r o t o t y p e , further refinement of immobilization devices should be undertaken to minimize the morbidity of suspected neck injuries.
REFERENCES 1. Huelke DF, O'Day J, Mendelsohn RA: Cervical injuries suffered in automobile crashes. J Neurosurg 1981;54:316-322. 2. Riggins RS, Kraus JF: The risk of neurologic damage with fractures of the vertebrae. J Trauma 1977;17:126-133. 3. Cloward RB: Acute cervical spine injuries. Clin Syrup 1980;32:15, 4. American Academy of Orthopaedic Surgeons: Emergency Care and Transportation of the Sick and Injured, ed 3. Menasha, Washington, AAOS, 1981. 5. Dick T, Land R: Spinal immobilization devices. J Emerg Med Serv 1982;7:26-32. 6. Johnson RM, Hart DL, Simmons EF, et al: Cervical erthoses. J Bone JointSurg 1977;59A:332-339. 7. Kaufman WA, Lunsford TR, Lunsford BR, et al: Comparison of three prefabricated cervical collars. OrthotProethetl986;39:21-28. 8. Pedolsky S, Baraff LJ, Simon RR, et al: Efficacy of cervical spine immobilization methods. J Trauma 1983;23:461-465. 9. McCabe JB, Nolan DJ: Comparison of the effectiveness of different cervical immobilization collars. Ann Emerg Med 1986;15:50-53. 10. Fisher SV, Bowar JF, Awad EA, et al: Cervical orthoses effect on cervical spine motion: Roentgenographic and goniometric method of study. Arch Phys Med Rehab 1977;58:109-115.
11, Hartman JT, Palumbo F, Hill BJ: Cineradiegraphy of the braced normal cervica{ spine. Clin Orthop 1975;189:97-182. 12. Jones MD: Cineradiographic studies of the collar-immobilized cervical spine. J Neurosurg 1960;17:633-637. Address for reprints: Robert L Waters, MD 7601 East Imperial Highway HB 117 Downey, California 90242
22/ 1188
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OCTOBER 1992
