J Neurosurg 72:210-215, 1990
Management of cervical spine injuries in patients with ankylosing spondylitis KARL N. DETWILER, M.D., CHRISTOPHER M. LOFTUS, M.D., JOHN C. GODERSKY, M.D., AND ARNOLD H. MENEZES, M.D. Division of Neurosurgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa ~," Eleven patients with ankylosing spondylitis and traumatic fracture/dislocation of the spine were identified in a retrospective review of all cases of cervical spine injury treated on the neurosurgical service over a 10-year period. Injury was most often secondary to minor trauma or a motor-vehicle accident, and the level of vertebral involvement was most frequently between C-5 and T-1. Neurological symptoms at presentation ranged from neck pain alone to complete loss of function distal to the level of injury. Initial routine treatment consisted of axial traction for realignment with the minimal weight needed to accomplish this, taking into account the flexion deformity. All patients underwent pluridirectional tomography and/or computerized tomography to delineate the exact sites of injury. Three patients died shortly after admission due to pulmonary complications. The remaining eight patients underwent early posterior stabilization and mobilization in a halo or cervicothoracic brace to achieve fusion. Neurological improvement was achieved in six of these eight cases. The experience described here supports the initiation of axial traction as initial therapy for cervical injuries followed by early surgical stabilization in patients with ankylosing spondylitis. The difficulty of maintaining spinal alignment and the devastating pulmonary problems attendant on conservative management may be obviated by early fusion.
KEY WORDS
A
ankylosing spondylitis
NKYLOSINGspondylitis, the term officially adopted in 1963 by rheumatologists in the United States 2 for the disease first described in 1897 by Strtimpel131 and in 1898 by Marie, 22 may result in severe reduction of spinal mobility. The incidence of spinal injury in these patients is relatively low, but when it does occur it is primarily localized to the cervical spine. 16,17,35The rigidly fused " b a m b o o spine" or "poker spine," when fractured, behaves somewhat like a long bone, and is subsequently extremely unstable with an associated high risk o f neurological deterioration, t4,26 In the subgroup of spinal-trauma patients with ankylosing spondylitis, the morbidity and mortality rates are disproportionately higher than those with routine cervical spine injuries. 18,24,29,36 The current study reviews those patients with ankylosing spondylitis treated for traumatic cervical spine injury at our institution in an effort to identify a safe and efficient way to manage these complex cases. The initial treatment, radiographic investigation, medical/ surgical management, complications, morbidity, and mortality are discussed.
21 0
spinal cord injury
9 cervical spine injury
Summary of Cases Clinical M a t e r i a l Eleven patients (two women and nine men) were admitted to the University of Iowa Hospitals and Clinics between April, 1977, and April, 1987, with combined traumatic cervical spine injury and ankylosing spondylitis. The mean age was 67 years (range 38 to 81 years). Each patient had a moderate to severe preexisting flexion deformity of the cervical spine. The demographic data, preinjury level of function, etiology of the spinal trauma, and mechanism of injury are summarized in Table 1. Three patients required a walker for ambulation prior to their injury; this was necessitated by severe ankylosis of the hips. The trauma in each case was of low intensity. Six patients sustained trauma from falls, one with a major fall approximately 6 feet off a ladder and the remainder with only minor falls while either walking or standing. In none of these falls was there an associated loss of consciousness or significant injury. The remaining five patients were all involved in motor-vehicle accidents; the spinal fracture/
J, Neurosurg. / Volume 72/February, 1990
Cervical injuries in cases with ankylosing spondylitis TABLE 1
TABLE 2
Clinical presentalion (?f l 1 patients with ankylosing spondylitis and cervical spine injury
Radiographic,findings in l I patiems with ankylosing spondylilis and cervical spine injury*
Case No,
Case Spinal Disto- Pedicle Lamina Body Myelographic No. Level cation Fracture Fracture Fracture Compression
1 2 3 4
Age (yrs), Sex 70, M 73, M 80, M 73. F
5 6 7 8 9 10 11
66, M 81, M 38, M 55, F 7l, M 71, M 57, M
Preinjury Level of Activity
Type of Accident*
Type of Injury
ambulato~ with walker ambulatory' with walker normal ambulatory with walker, paresthesia of hands normal normal normal normal normal normal normal
fell walking fellstanding fell standing fellwalking
flexion extension extension extension
MVA fell 6 ft MVA fell walking MVA MVA MVA
extension extension extension extension extension extension flexion
1 C6-7 posterior 2 C1-2 anterior 3 C5-6 anterior 4 C4-5 anterior 5 C6-7 anterior 6 C7-T1 anterior 7 C7-T1 anterior 8 C4-5 anterior 9 C7-TI anterior 10 C7-T1 anterior tl C5-6 posterior *+ = injuryr present; - =
. . . + + . . . + + + iniury absent.
+ . + . + + -
+ + + + -
* MVA = motor-vehicle accident. TABLE 3 dislocation was the o n l y m a j o r t r a u m a they suffered, except for m i l d head i n j u r i e s i n two. I n each case n o n e o f the other passengers i n v o l v e d i n the accident was injured. Radiographic studies a n d / o r intraoperative findings revealed several types o f structural a b n o r m a l i t i e s (Table 2). Fracture a n d / o r dislocation occurred at the C 1 - 2 interspace in o n e patient, the C 4 - 5 interspace in two, the C 5 - 6 interspace in two, the C 6 - 7 interspace in two, a n d at the C 7 - T 1 level in four patients. All b u t two injuries were a n t e r i o r s u b l u x a t i o n s secondary to hyperextension. Cases 1 a n d 1 1 h a d posterior dislocations seco n d a r y to flexion injuries. M u l t i p l e levels of involvem e n t were seen i n two cases.
Classification ( f neurotogical d~[~cit at time of admission correlated with grade at discharge*
f i
Admission Grade
Outcome A
A B
2 0
c D
i, It
!
B
C
D
E
0 0
0 0
0 0
0 0
~
o 0
o 0
o 4
o 2
I
E 17 0 0 0 0 * Classification according to Frankel, et aL js t Indicates those patients who died after admission due to pulmonary complications.
Neurological Deficit At admission, the severity o f the neurological deficit was rated according to the classification of Frankel, et at./3 where G r a d e A i n c l u d e s patients with complete m o t o r a n d sensory loss; G r a d e B patients have n o m o t o r function, b u t p r e s e r v a t i o n o f sensation; G r a d e C patients have i n t a c t b u t f u n c t i o n a l l y useless m o t o r function; G r a d e D i n c l u d e s p a t i e n t s with useful m o t o r power; a n d G r a d e E patients are without deficit. At admission, one p a t i e n t (Case 6) was classified as G r a d e E, only c o m p l a i n i n g o f neck a n d intrascapular p a i n (Table 3); seven p a t i e n t s were classified as G r a d e D, one patient (Case 3) as G r a d e C, a n d two patients (Cases 7 a n d 11) as G r a d e A.
Treatment All patients were initially placed in axial traction for spinal r e a l i g n m e n t , except for Case 6, who r e m a i n e d in a Philadelphia collar, T h e traction vector was superior a n d anterior to keep the n e c k flexed, which is n o r m a l for these patients (Fig. !). I n nearly all cases, satisfactory reduction was achieved with less t h a n 10 lb of weight. Following r e a l i g n m e n t all patients u n d e r w e n t either
J. ?~2"urosurg. / Volume 72/February, 1990
pluridirectional t o m o g r a p h y or m y e l o g r a p h y with or w i t h o u t c o m p u t e r i z e d t o m o g r a p h y (CT) to further i d e n tify the pathology. Seven of the 1 1 p a t i e n t s u n d e r w e n t posterior f u s i o n for p e r m a n e n t s t a b i l i z a t i o n b e t w e e n 1 a n d 10 days after admission. A n o t h e r h a d f u s i o n 4 weeks p o s t i n j u r y after stabilization o f his m e d i c a l p r o b l e m s . In four o f these eight patients, a c o n c u r r e n t posterior d e c o m p r e s s i o n was performed. Postoperatively, p a t i e n t s were initially m a i n t a i n e d i n axial t r a c t i o n , followed b y early m o b i l i zation in a halo or cervicothoracic brace,
Outcome Patients w h o s u r v i v e d t h e i r initial t r e a t m e n t a n d u n d e r w e n t surgical fusion were discharged with either stable or i m p r o v i n g n e u r o l o g i c a l findings (Table 3). T w o patients (Cases 8 a n d 9) had resolution o f all deficits, a n d a t h i r d p a t i e n t (Case 4) recovered all m o t o r f u n c t i o n b u t her sensory deficits persisted. T h r e e patients (Cases 2, 5, a n d 10) r e m a i n e d i n G r a d e D w i t h o u t change in their m o t o r deficits, b u t each had r e s o l u t i o n 211
K. N. Detwiler, et al.
FIG. 1. Schematic illustration of traction apparatus for treatment of patients with cervical spine injuries and ankylosing spondylitis. An effort was made to keep the neck in a flexed position which we considered was the normal position at rest for these patients. Accordingly, weights and tongs were applied so as to keep the force vector in a superior-anterior direction.
of all sensory deficits. T w o patients (Cases 7 and 11) had no recovery o f sensory or m o t o r function. Complications Three patients suffered neurological deterioration while immobilized. Case 1 had successful realignment of a posterior C 6 - 7 subluxation after the neck was placed in a flexed position; however, due to neck pain, the patient refused this position. Realignment with the neck in minimal extension resulted in a complete T-3 myelopathy, followed by p u l m o n a r y complications and death. Another patient (Case 3) aspirated while in traction, despite a functioning nasogastric tube, and suffered a respiratory arrest. Following emergency intubation, during which his neck was extended, a complete C-5 myelopathy developed; aspiration pneumonia and death ensued. One patient (Case 6) with an anterior C7-T1 subluxation (Fig. 2) and a T-6 compression fracture, but without neurological deficit, was placed at flat bed rest while in a Philadelphia collar. The day following admission he acutely developed an incomplete T-2 myelopathy which partially resolved with axial traction. Acute respiratory insufficiency developed, followed by a respiratory arrest. The patient died secondary to anoxic cerebral damage. Another patient (Case 7) underwent emergency C 3 - T 1 l a m i n e c t o m y for an epidural h e m a t o m a along with a C 6 - T 1 fusion with rib and wire. Postoperatively, he developed recurrent p n e u m o n i a and was ventilatordependent for 2 weeks. At discharge his neurological deficit was unchanged. Three months after being placed 212
FIG. 2. Plain lateral x-ray film of Case 6. This patient with a C7-T 1 anterior subluxation (arrow) was without neurological deficit at the time of admission. Acute respiratory insufficiency developed after 24 hours in the hospital and, after unsuccessful intubation, a tracheostomy was performed. The patient died due to anoxic cerebral damage associated with the protracted intubation episode.
in the halo brace, the apparatus was removed without our knowledge at an outside rehabilitation unit. The patient returned 1 year postoperatively with new pain in his neck, left arm, and shoulder; his head was resting on his left shoulder. Reoperation revealed nonunion at C 7 - T 1 on the right. The earlier fusion was taken down and a rectangular Luque rod placed with the cervical spine in a neutral position. At discharge the patient's neurological status was unchanged and he was placed in a halo vest for 3 months. Since removal of the vest, his fusion has remained stable. Despite early mobilization following surgical fusion, two other patients (Cases 5 and 11) developed postoperative pneumonia, which responded to antibiotic treatment in both cases. Discussion The estimated incidence of ankylosing spondylitis in the general population is 1.4%. 4 Since the first reported case of cervical spinal cord injury associated with ankylosing spondylitis in 1933, 3o similar reports have appeared only sporadically. In patients with ankylosing spondylitis the occurrence o f traumatic cervical spine injury is 3.5 times greater than the incidence in the normal population. In several large series of cases with spinal cord injuries, the percentage of patients with associated ankylosing spondylitis has varied between 0.3% a n d 0 . 5 % , 1"12"15'38
The characteristic pathological lesions in ankylosing spondylitis are vertebral body osteoporosis, ankylosis J. Neurosurg. / Volume 72/February, 1990
Cervical injuries in cases with ankylosing spondylitis of the apophyseal joints, intervertebral disc calcification, and ligamentous ossification. 6 The vertebrae may develop stress fractures as severe osteoporosis weakens the ankylosed spine. 37 The apophyseal joints undergo progressive destructive changes which lead to eventual ossification, joint narrowing, and ankylosis? 5 Calcification of the anulus fibrosis reduces the movement and elasticity of the intervertebral disc, causing this point to be the site of least resistance when the spine is subjected to trauma. In 13 of 20 patients reported by Weinstein, et al., 35 the fracture began in the interspace. Similar localization to the intervertebral disc space was noted in nine of our 1 1 patients. The ligamentous fragility and multiple fused vertebral segments cause the fractured ankylotic spine to resemble a long-bone fracture. In the absence of bone and ligament stability, the only means of spinal stabilization left in these patients is the cervical musculature. The precipitating trauma may be minor in these c a s e s . 9AOA2'I6,I8.I9`25,26,35'36 In our patients who fell, the majority of the injuries occurred in falls while either standing or walking, without significant associated injury. In patients involved in motor-vehicle accidents, we were unable to ascertain whether the patients were using any restraining devices. However, it is noteworthy that no other individuals involved in these accidents were injured, reinforcing the relatively minor nature of the events. These patients should be advised to use aids for ambulation, 35"38and to avoid alcohol 12'14'23'27'36 and chiropractic manipulations. 28 As with cervical spine fractures in the general population, traumatic fracture/dislocation in the patient with ankylosing spondylitis usually occurs in the lower cervical spine (C-5 to T-l). Hunter and Dubo ~6 and Kiwerski, et al., 2~ found injury in this region in 40 (83.3%) of 48 cases and 26 (78.8%) of 33 cases, respectively. Similarly, eight (73.0%) of our 11 patients suffered injuries to the C5-T1 region. In our subjects, nine (82.0%) suffered a hyperextension injury. Reports by several g r o u p s 3'5"15'24'25~27'33'34'36 have implicated hyperextension as the most frequent mechanism of injury. When these patients fall forward, their face customarily strikes the ground first, since the head juts forward due to a severely kyphotic thoracic spine. This impact forces the neck into hyperextension fracturing the brittle spine. If the patient were to fall backward, the flexed neck and head are then forced posteriorly by the weight of the head, again causing a hyperextension injury. In this patient population, a recent increase in neck pain or an acute change in neurological status, even if no trauma has occurred, are indications for full radiographic study of the vertebral column as multiple spinal fractures, while rare, have been reported. ~4"25Our Case 6 suffered spinal fractures in both the cervical and thoracic regions, but had no apparent deficit on presentation. Thus, studies should include the full spine, and not be limited to the symptomatic region. These studies should include plain films, tomography, and CT. Magnetic resonance imaging is often not feasible, J. Neurosurg. / Volume 7 2 / F e b r u a r y , 1990
and in many of these cases cervical myelography continues to be required to image the spinal cord pathology. Proper initial treatment of the patient with ankylosing spondylitis and acute cervical trauma is crucial to ensure a successful outcome. Ambulance personnel and emergency room staff should be educated that the routinely recommended neutral position, with the head secured to a back board, can be disastrous in these patients. 7 Numerous cases have been described where such care has caused the condition of asymptomatic patients or those with only minor neurological abnormalities to w o r s e n . 18'24'26~32 This can be avoided if the diagnosis of ankylosing spondylitis is suspected in every case where patients voluntarily hold their head in a significant degree of flexion. 26 A vacuum cushion can be individually fitted to the patient during transport, and will maintain the normal cervical flexion. 32 Once confirmation of a fracture/dislocation is made, patients with ankylosing spondylitis are best treated with axial traction. Use of a collar, as in our Case 6, is clearly inadequate, as this patient soon developed an incomplete myelopathy which led to his death. The traction vector must be placed in a superior and anterior direction such that the patient is realigned to his preexisting kyphosis, and minimal weight should be used. Placing the neck in an extended position may precipitate neurological decline as it did in our Cases 1 and 3. Even with properly positioned axial traction, the possibility of further neurological deterioration exists, as this means of immobilization still allows for rotational movement.21.24 The halo brace alone has been advocated by many as the optimal mode of treatment, but is not without complications. 16.~9,32,35,38While the majority of patients placed in a halo brace achieve spinal fusion without difficulty, failures of union or increased neurological deficit while in the halo brace have been described. ~6'3z'35 In our Case 7 the failure of fusion while in a halo brace was certainly related to premature removal of the vest. Furthermore, the disruption of both the anterior and posterior supporting structures that often accompanies the fracture/dislocation may lead to an instability of such degree that halo fixation is not successful. Pressure ulcerations are more prone to develop beneath the halo vest due to the extensive thoracic kyphosis. This complication can usually be alleviated by scrupulous padding or the use of custom-fitted vests. Controversy exists as to whether patients with a fracture/dislocation should be treated with external immobilization alone or with surgical fusion followed by external immobilization. A neurological deficit which can be related to radiographic evidence of cord or nerve root compression is a clear indication for a decompressive laminectomy and f u s i o n . 14'17'35 After reduction of the malalignment by traction, eight of our 1 1 patients underwent surgical fusion via a posterior approach. O f this operative group, four patients also underwent decompressive laminectomy. In our limited series, surgical stabilization has produced results compatible with 21 3
K. N. Detwiler, et al. those seen with external immobilization alone. In an attempt to decrease the risk of respiratory complications, patients are mobilized in a halo brace as soon after surgery as medically feasible. In our series, pneumonia or respiratory insufficiency developed in six (55%) of 11 patients and was either a major contributing factor or the actual cause of death in three. This is similar to the experience of others. 2~ The pulmonary system complications c o m m o n l y seen in spinal cord injuries are c o m p o u n d e d in the patient with ankylosing spondylitis as the lungs are frequently fibrotic and the ribs ankylosed, thus fixing the rib cage. A spinal epidural h e m a t o m a was noted in one of our patients (9%). This would seem much higher than the 1% to 2% incidence of this complication reported for traumatic cervical spine injuries in patients with an otherwise normal spine. ~ Farhat, et al., 8 proposed that ankylosing spondylitis affects the cancellous bone in such a way that, when fractured, there is persistent oozing which may predispose to formation o f an epidural hematoma. Three of our patients died before definitive therapy could be instituted. In each of these cases a complication related to the pulmonary system was the initial event which led to their death. Neurological deficits remained after treatment, or at death, in nine (82%) of the 11 patients. These values are similar to those presented by Foo and Rossier; ~t 85.7% of their treated patients had permanent deficits and they reported a 57.1% mortality rate. In elderly patients and those with a complete cord lesion, the presence of ankylosing spondylitis leads to an especially poor prognosis, with a high mortality rate ranging from 35% to 5 0 % . 12'17'20'35'38 Conclusions
Eleven patients with ankylosing spondylitis and acute cervical spine injury were treated over a 10-year period. The incidence of cervical spine fractures was higher in these patients than in the general population. The pathological changes of the cervical spine inherent in ankylosing spondylitis predisposed these patients to spinal fracture and dislocation after relatively m i n o r trauma. Injury occurred more frequently in the lower cervical spine. Neurological improvement was the rule following early surgical stabilization and ambulation in a halo brace in those patients who did not have complete lesions. Complications occurred in one-half o f our patients, the majority of which were secondary to respiratory difficulties. The mortality rate was high (27%), again secondary to pulmonary complications. We r e c o m m e n d a treatment plan for this group of patients consisting of initial axial traction (taking into account the patients' flexion deformity). Under only extreme circumstances should the neck be placed in a neutral or extended position. Following realignment, the patient should have early surgical stabilization via a posterior approach with early mobilization in a halo brace in an attempt to decrease the respiratory difficulties inherent in these patients. 214
References
1. Bohlman HH: Acute fractures and dislocations of the cervical spine. An analysis of three hundred hospitalized patients and review of the literature. J Bone Joint Surg (Am) 61:1119-1142, 1979 2. Boland EW: Ankylosing spondylitis, in Hollander JL (ed): Arthritis and Allied Conditions: A Textbook of Rheumatology, ed 7. Philadelphia: Lea & Febiger, 1966, pp
633-655 3. Burke DC: Hyperextension injuries of the spine. J Bone Joint Surg (Br) 53:3-12, 1971 4. Calin A, Fries JF: Striking prevalence of ankylosing spondylitis in 'healthy' W27 positive males and females. N Engl J Med 193:835-839, 1975 5. Cheshire DJE: The stability of the cervical spine following the conservative treatment of fractures and fracture-dislocations. Paraplegia 7:193-203, 1969 6. Cruickshank B: Histopathology of diarthrodial joints in ankylosing spondylitis. Ann Rheum Dis 10:393-404, 1951 7. DePalma A: The Management of Fractures and Dislocations, ed 2. Philadelphia: WB Saunders, 1970, Vol 1, pp 296-300 8. Farhat SM, Schneider RC, Gray JM: Traumatic spinal extradural hematoma associated with cervical fractures in rheumatoid spondylitis. J Trauma 13:591-599, 1973 9. Fast A, Parikh S, Matin EL: Spine fractures in ankylosing spondylitis. Arch Phys Med Rehabil 67:595-597, 1986 10. Foo D, Bignami A, Rossier AB: Two spinal cord lesions in a patient with ankylosing spondylitis and cervical spine injury. Neurology 33:245-249, 1983 l l. Foo D, Rossier AB: Post-traumatic spinal epidural hematoma. Neurosurgery 11:25-32, 1982 12. Foo D, Sarkarati M, Marcelino V: Cervical spinal cord injury complicating ankylosing spondylitis. Paraplegia 23: 358-363, 1985 13. Frankel HL, Hancock DO, Hyslop G, et al: The value of postural reduction in the initial management of closed injuries of the spine with paraplegia and tetraplegia. Part 1. Paraplegia 7:179-192, 1969 14. Grisolia A, Bell RL, Peltier LF: Fractures and dislocations of the spine complicating ankylosing spondylitis. A report of six cases. J Bone Joint Surg (Am) 49:339-386, 1967 15. Guttmann L: Traumatic paraplegia and tetraplegia in ankylosing spondylitis. Paraplegia 4:188-203, 1966 16. Hunter T, Dubo H: Spinal fractures complicating ankylosing spondylitis. Ann Intern Med 88:546-549, 1978 17. Hunter T, Dubo HIC: Spinal fractures complicating ankylosing spondylitis. A long-term followup study. Arthritis Rheum 26:751-759, 1983 18. Janda WE, Kelly PJ, Rhoton AL Jr, et al: Fracturedislocation of the cervical part of the spinal column in patients with ankylosing spondylitis. Proc Staff Meet Mayo Clin 43:714-721, 1968 19. Kewalramani LS, Taylor RG, Albrand OW: Cervical spine injury in patients with ankylosing spondylitis. J Trauma 15:931-934, 1975 20. Kiwerski J, Wieclawek H, Garwacka I: Fractures of the cervical spine in ankylosing spondylitis. Int Orthop 8: 243-246, 1985 21. Lemmen LJ, Laing PG: Fracture of the cervical spine in patients with rheumatoid arthritis. J Neurosurg 16: 542-550, 1959 22. Marie P: Sur la spondylose rhizom61ique. Rev Med 18: 285-315, 1898 23. MurrayGC, Persellin RH: Cervical fractures complicating ankylosing spondylitis. A report of eight cases and review of the literature. Am J Med 70:1033-1041, 1981 24. Osgood C, Martin LG, Ackerman E: Fracture-dislocation J. Neurosurg. / Volume 72/February, 1990
Cervical injuries in cases with ankylosing spondylitis
25. 26.
27. 28. 29. 30. 31. 32.
of the cervical spine with ankylosing spondylitis. Report of two cases. J Neurosurg 39:764-769, 1973 Osgood CP, Abbasy M, Mathews T: Multiple spine fractures in ankylosing spondylitis. J Trauma 15:163-166, 1975 Podolsky SM, Hoffman JR, Pietrafesa CA: Neurological complications following immobilization of cervical spine fractures in a patient with ankylosing spondylitis. Ann Emerg Med 12:578-580, 1983 Rand RW, Stern WE: Cervical fractures of the ankylosed rheumatoid spine. Neurochirurgia 4:137-148, 1961 Rinsky LA, Reynolds GG, Jameson RM, et al: A cervical spinal cord injury following chiropractic manipulation. Paraplegia 13:223-227, 1976 Rogers WA: Fractures and dislocations of the cervical spine. An end-result study. J Bone Joint Surg (Am) 39: 341-376, 1957 Stiasny H: Fraktur der Halswirbels~iule bei Spondylarthritis ankylopoetica (Bechterew). Zentralbl Chir 60: 998-1001, 1933 Strtimpell A: Bemerkiing fiber die chronische ankylosirende Entztindung der Wirbels~iule und der H/iftgelenke. Dtsch Z Nervenheilkd 11:338-342, 1897 Surin VV: Fractures of the cervical spine in patients with ankylosing spondylitis. Acta Orthop Scand 51:79-84, 1980
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33. Symonds C: The interrelation of trauma and cervical spondylosis in compression of the cervical cord. Lancet 1:451-454, 1953 34. Taylor AR: Mechanism and treatment of spinal-cord disorders associated with cervical spondylosis. Lancet 1: 717-720, 1953 35. Weinstein PR, Karpman RR, Gall EP, et al: Spinal cord injury, spinal fracture, and spinal stenosis in ankylosing spondylitis. J Neurosurg 57:609-616, 1982 36. Woodruff FP, Dewing SB: Fracture of the cervical spine in patients with ankylosing spondylitis. Radiology 80: 17-21, 1963 37. Yau ACMC, Chan RNW: Stress fracture of the fused lumbo-dorsal spine in ankylosing spondylitis. A report of three cases. J Bone Joint Surg (Br) 56:681-687, 1974 38. Young JS, Cheshire DJE, Pierce JA, et al: Cervical ankylosis with acute spinal cord injury. Paraplegia 15: 133-146, 1977
Manuscript received January 18, 1989. Accepted in final form July 21, 1989. Address reprint requests to." Christopher M. Loftus, M.D., Division of Neurological Surgery, C42 GH, University of Iowa Hospitals and Clinics, Iowa City, Iowa 52242.
215
Management of cervical spine injuries in patients with ankylosing spondylitis KARL N. DETWILER, M.D., CHRISTOPHER M. LOFTUS, M.D., JOHN C. GODERSKY, M.D., AND ARNOLD H. MENEZES, M.D. Division of Neurosurgery, University of Iowa Hospitals and Clinics, Iowa City, Iowa ~," Eleven patients with ankylosing spondylitis and traumatic fracture/dislocation of the spine were identified in a retrospective review of all cases of cervical spine injury treated on the neurosurgical service over a 10-year period. Injury was most often secondary to minor trauma or a motor-vehicle accident, and the level of vertebral involvement was most frequently between C-5 and T-1. Neurological symptoms at presentation ranged from neck pain alone to complete loss of function distal to the level of injury. Initial routine treatment consisted of axial traction for realignment with the minimal weight needed to accomplish this, taking into account the flexion deformity. All patients underwent pluridirectional tomography and/or computerized tomography to delineate the exact sites of injury. Three patients died shortly after admission due to pulmonary complications. The remaining eight patients underwent early posterior stabilization and mobilization in a halo or cervicothoracic brace to achieve fusion. Neurological improvement was achieved in six of these eight cases. The experience described here supports the initiation of axial traction as initial therapy for cervical injuries followed by early surgical stabilization in patients with ankylosing spondylitis. The difficulty of maintaining spinal alignment and the devastating pulmonary problems attendant on conservative management may be obviated by early fusion.
KEY WORDS
A
ankylosing spondylitis
NKYLOSINGspondylitis, the term officially adopted in 1963 by rheumatologists in the United States 2 for the disease first described in 1897 by Strtimpel131 and in 1898 by Marie, 22 may result in severe reduction of spinal mobility. The incidence of spinal injury in these patients is relatively low, but when it does occur it is primarily localized to the cervical spine. 16,17,35The rigidly fused " b a m b o o spine" or "poker spine," when fractured, behaves somewhat like a long bone, and is subsequently extremely unstable with an associated high risk o f neurological deterioration, t4,26 In the subgroup of spinal-trauma patients with ankylosing spondylitis, the morbidity and mortality rates are disproportionately higher than those with routine cervical spine injuries. 18,24,29,36 The current study reviews those patients with ankylosing spondylitis treated for traumatic cervical spine injury at our institution in an effort to identify a safe and efficient way to manage these complex cases. The initial treatment, radiographic investigation, medical/ surgical management, complications, morbidity, and mortality are discussed.
21 0
spinal cord injury
9 cervical spine injury
Summary of Cases Clinical M a t e r i a l Eleven patients (two women and nine men) were admitted to the University of Iowa Hospitals and Clinics between April, 1977, and April, 1987, with combined traumatic cervical spine injury and ankylosing spondylitis. The mean age was 67 years (range 38 to 81 years). Each patient had a moderate to severe preexisting flexion deformity of the cervical spine. The demographic data, preinjury level of function, etiology of the spinal trauma, and mechanism of injury are summarized in Table 1. Three patients required a walker for ambulation prior to their injury; this was necessitated by severe ankylosis of the hips. The trauma in each case was of low intensity. Six patients sustained trauma from falls, one with a major fall approximately 6 feet off a ladder and the remainder with only minor falls while either walking or standing. In none of these falls was there an associated loss of consciousness or significant injury. The remaining five patients were all involved in motor-vehicle accidents; the spinal fracture/
J, Neurosurg. / Volume 72/February, 1990
Cervical injuries in cases with ankylosing spondylitis TABLE 1
TABLE 2
Clinical presentalion (?f l 1 patients with ankylosing spondylitis and cervical spine injury
Radiographic,findings in l I patiems with ankylosing spondylilis and cervical spine injury*
Case No,
Case Spinal Disto- Pedicle Lamina Body Myelographic No. Level cation Fracture Fracture Fracture Compression
1 2 3 4
Age (yrs), Sex 70, M 73, M 80, M 73. F
5 6 7 8 9 10 11
66, M 81, M 38, M 55, F 7l, M 71, M 57, M
Preinjury Level of Activity
Type of Accident*
Type of Injury
ambulato~ with walker ambulatory' with walker normal ambulatory with walker, paresthesia of hands normal normal normal normal normal normal normal
fell walking fellstanding fell standing fellwalking
flexion extension extension extension
MVA fell 6 ft MVA fell walking MVA MVA MVA
extension extension extension extension extension extension flexion
1 C6-7 posterior 2 C1-2 anterior 3 C5-6 anterior 4 C4-5 anterior 5 C6-7 anterior 6 C7-T1 anterior 7 C7-T1 anterior 8 C4-5 anterior 9 C7-TI anterior 10 C7-T1 anterior tl C5-6 posterior *+ = injuryr present; - =
. . . + + . . . + + + iniury absent.
+ . + . + + -
+ + + + -
* MVA = motor-vehicle accident. TABLE 3 dislocation was the o n l y m a j o r t r a u m a they suffered, except for m i l d head i n j u r i e s i n two. I n each case n o n e o f the other passengers i n v o l v e d i n the accident was injured. Radiographic studies a n d / o r intraoperative findings revealed several types o f structural a b n o r m a l i t i e s (Table 2). Fracture a n d / o r dislocation occurred at the C 1 - 2 interspace in o n e patient, the C 4 - 5 interspace in two, the C 5 - 6 interspace in two, the C 6 - 7 interspace in two, a n d at the C 7 - T 1 level in four patients. All b u t two injuries were a n t e r i o r s u b l u x a t i o n s secondary to hyperextension. Cases 1 a n d 1 1 h a d posterior dislocations seco n d a r y to flexion injuries. M u l t i p l e levels of involvem e n t were seen i n two cases.
Classification ( f neurotogical d~[~cit at time of admission correlated with grade at discharge*
f i
Admission Grade
Outcome A
A B
2 0
c D
i, It
!
B
C
D
E
0 0
0 0
0 0
0 0
~
o 0
o 0
o 4
o 2
I
E 17 0 0 0 0 * Classification according to Frankel, et aL js t Indicates those patients who died after admission due to pulmonary complications.
Neurological Deficit At admission, the severity o f the neurological deficit was rated according to the classification of Frankel, et at./3 where G r a d e A i n c l u d e s patients with complete m o t o r a n d sensory loss; G r a d e B patients have n o m o t o r function, b u t p r e s e r v a t i o n o f sensation; G r a d e C patients have i n t a c t b u t f u n c t i o n a l l y useless m o t o r function; G r a d e D i n c l u d e s p a t i e n t s with useful m o t o r power; a n d G r a d e E patients are without deficit. At admission, one p a t i e n t (Case 6) was classified as G r a d e E, only c o m p l a i n i n g o f neck a n d intrascapular p a i n (Table 3); seven p a t i e n t s were classified as G r a d e D, one patient (Case 3) as G r a d e C, a n d two patients (Cases 7 a n d 11) as G r a d e A.
Treatment All patients were initially placed in axial traction for spinal r e a l i g n m e n t , except for Case 6, who r e m a i n e d in a Philadelphia collar, T h e traction vector was superior a n d anterior to keep the n e c k flexed, which is n o r m a l for these patients (Fig. !). I n nearly all cases, satisfactory reduction was achieved with less t h a n 10 lb of weight. Following r e a l i g n m e n t all patients u n d e r w e n t either
J. ?~2"urosurg. / Volume 72/February, 1990
pluridirectional t o m o g r a p h y or m y e l o g r a p h y with or w i t h o u t c o m p u t e r i z e d t o m o g r a p h y (CT) to further i d e n tify the pathology. Seven of the 1 1 p a t i e n t s u n d e r w e n t posterior f u s i o n for p e r m a n e n t s t a b i l i z a t i o n b e t w e e n 1 a n d 10 days after admission. A n o t h e r h a d f u s i o n 4 weeks p o s t i n j u r y after stabilization o f his m e d i c a l p r o b l e m s . In four o f these eight patients, a c o n c u r r e n t posterior d e c o m p r e s s i o n was performed. Postoperatively, p a t i e n t s were initially m a i n t a i n e d i n axial t r a c t i o n , followed b y early m o b i l i zation in a halo or cervicothoracic brace,
Outcome Patients w h o s u r v i v e d t h e i r initial t r e a t m e n t a n d u n d e r w e n t surgical fusion were discharged with either stable or i m p r o v i n g n e u r o l o g i c a l findings (Table 3). T w o patients (Cases 8 a n d 9) had resolution o f all deficits, a n d a t h i r d p a t i e n t (Case 4) recovered all m o t o r f u n c t i o n b u t her sensory deficits persisted. T h r e e patients (Cases 2, 5, a n d 10) r e m a i n e d i n G r a d e D w i t h o u t change in their m o t o r deficits, b u t each had r e s o l u t i o n 211
K. N. Detwiler, et al.
FIG. 1. Schematic illustration of traction apparatus for treatment of patients with cervical spine injuries and ankylosing spondylitis. An effort was made to keep the neck in a flexed position which we considered was the normal position at rest for these patients. Accordingly, weights and tongs were applied so as to keep the force vector in a superior-anterior direction.
of all sensory deficits. T w o patients (Cases 7 and 11) had no recovery o f sensory or m o t o r function. Complications Three patients suffered neurological deterioration while immobilized. Case 1 had successful realignment of a posterior C 6 - 7 subluxation after the neck was placed in a flexed position; however, due to neck pain, the patient refused this position. Realignment with the neck in minimal extension resulted in a complete T-3 myelopathy, followed by p u l m o n a r y complications and death. Another patient (Case 3) aspirated while in traction, despite a functioning nasogastric tube, and suffered a respiratory arrest. Following emergency intubation, during which his neck was extended, a complete C-5 myelopathy developed; aspiration pneumonia and death ensued. One patient (Case 6) with an anterior C7-T1 subluxation (Fig. 2) and a T-6 compression fracture, but without neurological deficit, was placed at flat bed rest while in a Philadelphia collar. The day following admission he acutely developed an incomplete T-2 myelopathy which partially resolved with axial traction. Acute respiratory insufficiency developed, followed by a respiratory arrest. The patient died secondary to anoxic cerebral damage. Another patient (Case 7) underwent emergency C 3 - T 1 l a m i n e c t o m y for an epidural h e m a t o m a along with a C 6 - T 1 fusion with rib and wire. Postoperatively, he developed recurrent p n e u m o n i a and was ventilatordependent for 2 weeks. At discharge his neurological deficit was unchanged. Three months after being placed 212
FIG. 2. Plain lateral x-ray film of Case 6. This patient with a C7-T 1 anterior subluxation (arrow) was without neurological deficit at the time of admission. Acute respiratory insufficiency developed after 24 hours in the hospital and, after unsuccessful intubation, a tracheostomy was performed. The patient died due to anoxic cerebral damage associated with the protracted intubation episode.
in the halo brace, the apparatus was removed without our knowledge at an outside rehabilitation unit. The patient returned 1 year postoperatively with new pain in his neck, left arm, and shoulder; his head was resting on his left shoulder. Reoperation revealed nonunion at C 7 - T 1 on the right. The earlier fusion was taken down and a rectangular Luque rod placed with the cervical spine in a neutral position. At discharge the patient's neurological status was unchanged and he was placed in a halo vest for 3 months. Since removal of the vest, his fusion has remained stable. Despite early mobilization following surgical fusion, two other patients (Cases 5 and 11) developed postoperative pneumonia, which responded to antibiotic treatment in both cases. Discussion The estimated incidence of ankylosing spondylitis in the general population is 1.4%. 4 Since the first reported case of cervical spinal cord injury associated with ankylosing spondylitis in 1933, 3o similar reports have appeared only sporadically. In patients with ankylosing spondylitis the occurrence o f traumatic cervical spine injury is 3.5 times greater than the incidence in the normal population. In several large series of cases with spinal cord injuries, the percentage of patients with associated ankylosing spondylitis has varied between 0.3% a n d 0 . 5 % , 1"12"15'38
The characteristic pathological lesions in ankylosing spondylitis are vertebral body osteoporosis, ankylosis J. Neurosurg. / Volume 72/February, 1990
Cervical injuries in cases with ankylosing spondylitis of the apophyseal joints, intervertebral disc calcification, and ligamentous ossification. 6 The vertebrae may develop stress fractures as severe osteoporosis weakens the ankylosed spine. 37 The apophyseal joints undergo progressive destructive changes which lead to eventual ossification, joint narrowing, and ankylosis? 5 Calcification of the anulus fibrosis reduces the movement and elasticity of the intervertebral disc, causing this point to be the site of least resistance when the spine is subjected to trauma. In 13 of 20 patients reported by Weinstein, et al., 35 the fracture began in the interspace. Similar localization to the intervertebral disc space was noted in nine of our 1 1 patients. The ligamentous fragility and multiple fused vertebral segments cause the fractured ankylotic spine to resemble a long-bone fracture. In the absence of bone and ligament stability, the only means of spinal stabilization left in these patients is the cervical musculature. The precipitating trauma may be minor in these c a s e s . 9AOA2'I6,I8.I9`25,26,35'36 In our patients who fell, the majority of the injuries occurred in falls while either standing or walking, without significant associated injury. In patients involved in motor-vehicle accidents, we were unable to ascertain whether the patients were using any restraining devices. However, it is noteworthy that no other individuals involved in these accidents were injured, reinforcing the relatively minor nature of the events. These patients should be advised to use aids for ambulation, 35"38and to avoid alcohol 12'14'23'27'36 and chiropractic manipulations. 28 As with cervical spine fractures in the general population, traumatic fracture/dislocation in the patient with ankylosing spondylitis usually occurs in the lower cervical spine (C-5 to T-l). Hunter and Dubo ~6 and Kiwerski, et al., 2~ found injury in this region in 40 (83.3%) of 48 cases and 26 (78.8%) of 33 cases, respectively. Similarly, eight (73.0%) of our 11 patients suffered injuries to the C5-T1 region. In our subjects, nine (82.0%) suffered a hyperextension injury. Reports by several g r o u p s 3'5"15'24'25~27'33'34'36 have implicated hyperextension as the most frequent mechanism of injury. When these patients fall forward, their face customarily strikes the ground first, since the head juts forward due to a severely kyphotic thoracic spine. This impact forces the neck into hyperextension fracturing the brittle spine. If the patient were to fall backward, the flexed neck and head are then forced posteriorly by the weight of the head, again causing a hyperextension injury. In this patient population, a recent increase in neck pain or an acute change in neurological status, even if no trauma has occurred, are indications for full radiographic study of the vertebral column as multiple spinal fractures, while rare, have been reported. ~4"25Our Case 6 suffered spinal fractures in both the cervical and thoracic regions, but had no apparent deficit on presentation. Thus, studies should include the full spine, and not be limited to the symptomatic region. These studies should include plain films, tomography, and CT. Magnetic resonance imaging is often not feasible, J. Neurosurg. / Volume 7 2 / F e b r u a r y , 1990
and in many of these cases cervical myelography continues to be required to image the spinal cord pathology. Proper initial treatment of the patient with ankylosing spondylitis and acute cervical trauma is crucial to ensure a successful outcome. Ambulance personnel and emergency room staff should be educated that the routinely recommended neutral position, with the head secured to a back board, can be disastrous in these patients. 7 Numerous cases have been described where such care has caused the condition of asymptomatic patients or those with only minor neurological abnormalities to w o r s e n . 18'24'26~32 This can be avoided if the diagnosis of ankylosing spondylitis is suspected in every case where patients voluntarily hold their head in a significant degree of flexion. 26 A vacuum cushion can be individually fitted to the patient during transport, and will maintain the normal cervical flexion. 32 Once confirmation of a fracture/dislocation is made, patients with ankylosing spondylitis are best treated with axial traction. Use of a collar, as in our Case 6, is clearly inadequate, as this patient soon developed an incomplete myelopathy which led to his death. The traction vector must be placed in a superior and anterior direction such that the patient is realigned to his preexisting kyphosis, and minimal weight should be used. Placing the neck in an extended position may precipitate neurological decline as it did in our Cases 1 and 3. Even with properly positioned axial traction, the possibility of further neurological deterioration exists, as this means of immobilization still allows for rotational movement.21.24 The halo brace alone has been advocated by many as the optimal mode of treatment, but is not without complications. 16.~9,32,35,38While the majority of patients placed in a halo brace achieve spinal fusion without difficulty, failures of union or increased neurological deficit while in the halo brace have been described. ~6'3z'35 In our Case 7 the failure of fusion while in a halo brace was certainly related to premature removal of the vest. Furthermore, the disruption of both the anterior and posterior supporting structures that often accompanies the fracture/dislocation may lead to an instability of such degree that halo fixation is not successful. Pressure ulcerations are more prone to develop beneath the halo vest due to the extensive thoracic kyphosis. This complication can usually be alleviated by scrupulous padding or the use of custom-fitted vests. Controversy exists as to whether patients with a fracture/dislocation should be treated with external immobilization alone or with surgical fusion followed by external immobilization. A neurological deficit which can be related to radiographic evidence of cord or nerve root compression is a clear indication for a decompressive laminectomy and f u s i o n . 14'17'35 After reduction of the malalignment by traction, eight of our 1 1 patients underwent surgical fusion via a posterior approach. O f this operative group, four patients also underwent decompressive laminectomy. In our limited series, surgical stabilization has produced results compatible with 21 3
K. N. Detwiler, et al. those seen with external immobilization alone. In an attempt to decrease the risk of respiratory complications, patients are mobilized in a halo brace as soon after surgery as medically feasible. In our series, pneumonia or respiratory insufficiency developed in six (55%) of 11 patients and was either a major contributing factor or the actual cause of death in three. This is similar to the experience of others. 2~ The pulmonary system complications c o m m o n l y seen in spinal cord injuries are c o m p o u n d e d in the patient with ankylosing spondylitis as the lungs are frequently fibrotic and the ribs ankylosed, thus fixing the rib cage. A spinal epidural h e m a t o m a was noted in one of our patients (9%). This would seem much higher than the 1% to 2% incidence of this complication reported for traumatic cervical spine injuries in patients with an otherwise normal spine. ~ Farhat, et al., 8 proposed that ankylosing spondylitis affects the cancellous bone in such a way that, when fractured, there is persistent oozing which may predispose to formation o f an epidural hematoma. Three of our patients died before definitive therapy could be instituted. In each of these cases a complication related to the pulmonary system was the initial event which led to their death. Neurological deficits remained after treatment, or at death, in nine (82%) of the 11 patients. These values are similar to those presented by Foo and Rossier; ~t 85.7% of their treated patients had permanent deficits and they reported a 57.1% mortality rate. In elderly patients and those with a complete cord lesion, the presence of ankylosing spondylitis leads to an especially poor prognosis, with a high mortality rate ranging from 35% to 5 0 % . 12'17'20'35'38 Conclusions
Eleven patients with ankylosing spondylitis and acute cervical spine injury were treated over a 10-year period. The incidence of cervical spine fractures was higher in these patients than in the general population. The pathological changes of the cervical spine inherent in ankylosing spondylitis predisposed these patients to spinal fracture and dislocation after relatively m i n o r trauma. Injury occurred more frequently in the lower cervical spine. Neurological improvement was the rule following early surgical stabilization and ambulation in a halo brace in those patients who did not have complete lesions. Complications occurred in one-half o f our patients, the majority of which were secondary to respiratory difficulties. The mortality rate was high (27%), again secondary to pulmonary complications. We r e c o m m e n d a treatment plan for this group of patients consisting of initial axial traction (taking into account the patients' flexion deformity). Under only extreme circumstances should the neck be placed in a neutral or extended position. Following realignment, the patient should have early surgical stabilization via a posterior approach with early mobilization in a halo brace in an attempt to decrease the respiratory difficulties inherent in these patients. 214
References
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33. Symonds C: The interrelation of trauma and cervical spondylosis in compression of the cervical cord. Lancet 1:451-454, 1953 34. Taylor AR: Mechanism and treatment of spinal-cord disorders associated with cervical spondylosis. Lancet 1: 717-720, 1953 35. Weinstein PR, Karpman RR, Gall EP, et al: Spinal cord injury, spinal fracture, and spinal stenosis in ankylosing spondylitis. J Neurosurg 57:609-616, 1982 36. Woodruff FP, Dewing SB: Fracture of the cervical spine in patients with ankylosing spondylitis. Radiology 80: 17-21, 1963 37. Yau ACMC, Chan RNW: Stress fracture of the fused lumbo-dorsal spine in ankylosing spondylitis. A report of three cases. J Bone Joint Surg (Br) 56:681-687, 1974 38. Young JS, Cheshire DJE, Pierce JA, et al: Cervical ankylosis with acute spinal cord injury. Paraplegia 15: 133-146, 1977
Manuscript received January 18, 1989. Accepted in final form July 21, 1989. Address reprint requests to." Christopher M. Loftus, M.D., Division of Neurological Surgery, C42 GH, University of Iowa Hospitals and Clinics, Iowa City, Iowa 52242.
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