Spinal Disorders: Fundamentals of Diagnosis and Treatment Part 108 ppsx

ab
c
d
Figure 5. Multisegmental posterior wedge osteotomy
This technique creates lordosis and is usually applied to one or multiple levels. a The spine is instrumented with pedicle
screws two levels above and below the planned osteotomies.
b The interspinous ligament and the adjoining spinous
process are resected with a rongeur. The yellow ligament is removed and v-shaped bilateral osteotomies are carried out
through the isthmus.
c These osteotomies are directed laterocranially at an angle of 30 –40 degrees. The desired slot
width of 5–7 mm is obtained by using appropriate rongeurs. If there is a scoliotic deformity, the osteotomies are made
slightly larger on the convex side.
d The rods are applied first cranially. The osteotomy gaps are closed by stepwise seg-
mental compression and connection to the rods. A posterior spinal fusion is added. With one single osteotomy approxi-
mately 10 degrees of correction can be achieved.
1074 Section Tumors and Inflammation
Osteotomies can be per-
formed at four to six levels
monic bending of the spine. In contrast to a closing wedge osteotomy, the MPWO
removes the posterior elements of a thoracic and/or lumbar level without the
need for a wedge excision of the vertebral body (
Fig. 5). Osteotomies can be per-
formed at four to six thoracic or lumbar levels depending on the extent and loca-
tion of the spinal deformity [47, 98]. With one singular osteotomy approximately
10 degrees of correction can be achieved [98]. The results of this technique are
satisfying [47] (
Table 7).
Cervical Wedge Osteotomy
Cervical closing wedge
osteotomy corrects severe
cervicothoracic kyphosis

A fixed cervicothoracic kyphotic deformity is rare (Case Study 1). However, this
deformity can cause a significant morbidity because of an impingement of the
chin with the chest, making eating and drinking difficult. Furthermore, patients
lose their horizontal gaze. A cervical corrective osteotomy was first described by
Uristin1958[95].Theopening wedge osteotom y wasoriginallycarriedoutat the
level of C7/T1 during local anesthesia. The osteotomy level is chosen at the cervi-
cothoracic junction because the vertebral artery only enters the spine at the level
of C6. With the advent of neuromonitoring, these interventions can today be per-
formed with the patient under general anesthesia and with less stress for the
patient. The disadvantage of the opening wedge osteotomy is the resulting ante-
rior gap with potential instability and need for an additional anterior fusion
(
Case Study 1). The correction of kyphosis can be balanced up to the level of lor-
dosis and corrections have been reported up to 54° [70]. Webb advocates a clos-
ing wedge osteotomy because of a better stability without the need for an uncon-
trolled cracking of the spine to achieve the correction [104] (
Fig. 6). Method of
choice is a closing wedge osteotomy with or without an anterior interbody fusion
depending on the fusion status of the anterior column. Case reports of chin on
chest deformities so far show excellent resolution of the deformity and solid
fusion [73]. Retrospective studies show that cervical spine surgery in AS appears
to have a fairly good clinical outcome [56] (
Table 7). However, this osteotomy is
very demanding and carries a high risk of neurological injuries [60, 70].
Treatment for Fracture and Spondylodiscitis
Fractures are most common
at thoracic level and
unstable
Fractures in AS patients are most commonly localized at the thoracic spine and
are very often unstable because they involve the anterior and posterior column

[10, 34, 77, 84, 109]. In contrast to a healthy individual, AS patients sustain frac-
tures more easily from minor trauma and experience fatigue fractures. These
fractures often remain occult (see above) as clinical symptoms are masked by
chronic pain. Not infrequently, the spine spontaneously corrects its kyphotic
deformity within the fracture (
Case Study 2). Thirty to 75% of cases are associ-
ated with severe neurological deficits [10, 34, 42, 77].
Instrumentation should be
long rather than short in AS
The general concepts of treatment also apply (see Chapters 30 , 31 , 36 )for
spinal injuries in AS and aseptic spondylodiscitis (Andersson lesions). In con-
trast to common fractures and spondylodiscitis, however, the stabilization
should be long rather than short because of the risk of a secondary kyphotic
deformity, implant failure and non-union. The degree of instability in AS deter-
mines the use of long instrumentation over a minimum of two vertebral bodies
above and below the lesion [59]. Laminectomy is indicated when defective posi-
tionsorbonyhypertrophyleadstoconstrictionorstenosisofthespinalcanalor
in the presence of epidural hematoma. Operative fracture stabilization is pre-
ferred to allow for early mobilization of the patient. However, treatment of spinal
fracture causing paralysis is difficult and controversial and is associated with
a high risk of complications [4, 10, 34, 42, 77, 78, 109]. Surgical management
Ankylosing Spondylitis Chapter 38 1075
ab
c
d
e
fg
Case Study 1
A 58-year-old male was diagnosed
with ankylosing spondylitis, which

had been present for over 20 years.
The patient was severely handi-
capped by his inability to look
straight ahead (
a). The standing lat-
eral radiograph demonstrated a sag-
ittal well balanced spine with the
deformity located at the cervicotho-
racic junction (
b, c). A cervical open-
ing wedge osteotomy at C7 was
done (
d). The spine was stabilized
with facet joint screws at C4 and C5
and pedicle screw fixation at T1 (
e).
In a second stage, an anterior inter-
corporal fusion and plate/screw fixa-
tion was added to close the gap and
additionally stabilize the spine (
f).
Postoperative photograph (g)shows
an excellent correction of the posi-
tion of the head.
1076 Section Tumors and Inflammation
ab
cd
Figure 6. Cervical closing wedge osteotomy
For this osteotomy the patient is positioned prone within a Mayfield headrest. Sensorimotor potentials should be
obtained prior to surgery as a baseline measurement.

a The spine is exposed from C4 to T3. Pedicle screws are inserted
three levels above and below the osteotomy. In the cervical spine, facet joint screws can be used as an alternative to pedi-
cle screws because of a lower risk of neurovascular injuries. The lamina of C7 and the hemilaminae of C6 and T1 are
resected. Care has to be taken to completely liberate the nerve roots C6 –8.
b The articular processes of C7 are
completely removed including the C7 pedicles. The vertebral body of C7 is decancellated with curettes and the posterior
wall osteomized with a Kerrison rongeur.
c Both rods are inserted and locked in the cervical screws. d The Mayfield head-
rest is loosened by an assistant who continues to manually hold the head during the correction. The rods are slowly
levered to the thoracic screws and locked. Great care has to be taken that the head extension does not result in a com-
promise of the nerve roots. A posterior spinal fusion completes the operation.
Treatment of fracture
causing paralysis is
associated with a high risk
of complications
of fractures or lesions in AS should be done in specialized interdisciplinary
clinics. The reasons are the high rate of complications (e.g., neurological fail-
ure, loss of fixation, wound infections, respiratory failure) and mortality post-
operatively.
Ankylosing Spondylitis Chapter 38 1077
ab
cd
e
f
Case Study 2
a A 59-year-old male who had suffered from ankylosing spondylitis for three
decades was well adapted to his disease. He sustained a fall on the stairs and
complained of weakness in his legs. At hospital admission the patient had a
mild paraparesis sub-L1 with decreased sensation and mild weakness in both
legs (MRC Grade 4). CT reformatted image (

b) shows a luxation fracture at L1
with significant posterior angulation of the spine. T1 and T2W MRI scans (
c, d)
demonstrate the luxation fracture and significant canal enchroachment. The
previously ankylosed kyphotic spine corrected at the level of the fracture. After
decompression of the spinal canal, the patient was instrumented with a pedicle
screw system in the corrected position. Fusion was added at the site of the frac-
ture (
e). At one year follow-up visit, the patient had completely recovered and
was very satisfied with the correction of the trunk position, which had bothered
him for many years prior to his fracture (
f).
1078 Section Tumors and Inflammation
Table 7. Surgical results of correction osteotomies
Author Cases Localiza-
tion
Design Technique Complications/outcome Conclusions
Langeloo
et al.
(2006) [60]
16 cervical retro-
spective
C7 correction
osteotomy (OT)
with internal fixa-
tion from C2–C6
to T1–T6
9 transient paresthesia
1 irreversible neurological
complication

2 deep wound infection
2 major general complica-
tion
C7 correction osteotomy is
a reliable technique. At the
cervical level neuromonito-
ring (TES-MEP) is manda-
tory
McMaster
et al.
(1997) [70]
15 cervical retro-
spective
C7/T1 extension
OT with (n =3)
and without
(n= 12) internal
fixation
2 transient paresthesia
2 irreversible neurological
complication
1 deep wound infection
4 subluxation
1 major general complica-
tion
cervical osteotomies are dif-
ficult techniques. Subluxa-
tion at the osteotomy site is
associated with non-union
Willems et

al. (2005)
[108]
105 cervical-
thoracic
and lumbar
retro-
spective
cervical-thoracic
OT (n= 22),
lumbar closing-
wedge OT (n=62),
polysegmental
lumbar OT
(n= 20), anterior-
posterior
lumbar OT (n=11)
8 transient paresthesia
9 irreversible neurological
complication
11 deep wound infection
12 major general complica-
tion
correction osteotomies in
AS show high complication
rates. Reasons are a difficult
surgery and a complex dis-
ease. AS surgery should be
carried out in specialized
interdisciplinary centers
Danisa

et al.
(2000) [33]
11 thoracic
and thora-
columbar
retro-
spective
“eggshell” osteo-
tomy
5 transient paresthesia
0 irreversible neurological
complication
0 deep wound infection
1 major general complica-
tion
an “eggshell” osteotomy
shows lower complication
ratesthanwithopenwedge
osteotomies. Main goal of
this procedure is to restore
sagittal balance
Van Royen
et al.
(1998) [98]
21 thoracic
and thora-
columbar
retro-
spective
polysegmental

lumbar OT
4 transient paresthesia
0 irreversible neurological
complication
7 deep wound infection
2 major general complica-
tion
polysegmental lumbar oste-
otomies are associated with
high complication rates.
Only in the mild phase of
AS should a polysegmental
lumbar osteotomy be used
Hehne et
al. (1990)
[47]
177 thoracic
and thora-
columbar
retro-
spective
polysegmental
lumbar OT
19 transient paresthesia
4 irreversible neurological
complication
6 deep wound infection
4 major general complica-
tion
the technique results in a

harmonious spinal correc-
tion. And reduces the
potential of severe compli-
cations. Most patients are
pain free after polysegmen-
tal lumbar OT
Bradford
et al.
(1987) [14]
21 thoracic
and thora-
columbar
retro-
spective
open wedge OT
(n= 8), two stage
osteotomy (ante-
rior and posterior)
(n=8)
2 transient paresthesia
0 irreversible neurological
complication
0 deep wound infection
0 major general complica-
tion
a neurological monitoring
with a wake-up test is nec-
essary. A correction of sagit-
tal balance seems to be
associated with decreased

risk of loss of correction
Lazennec
et al.
(1997) [63]
31 lumbar retro-
spective
open wedge OT
(n= 19) vs. close
wedge OT (
n= 12)
4 transient paresthesia
2 irreversible neurological
complication
3 reoperations (non-
union)
vs.
3 transient paresthesia
0 irreversible neurological
complication
1 reoperation (non-union)
the level of lumbar osteo-
tomy is very important,
because sagittal translation
is a basic mechanism for
correcting sagittal imbal-
ance
Ankylosing Spondylitis Chapter 38 1079
Complications
Surgical interventions for AS most often represent major surgery and are techni-
cally demanding. Not infrequently patients exhibit malnutrition and are prone to

infections. The morbidity and mortality rate can be decreased by careful surgical
planning, new operating techniques, new implants and improved intensive care
[26, 28, 29, 47, 60, 63, 72, 82, 86, 92, 100]. Complications after ankylosing surgery
include [28, 60, 98, 100, 108]:
transient paresthesia (0–45%)
postoperative infections (0–33%)
implant failure (2–33%)
loss of correction (5–40°)
irreversible neurological deterioration (0–10%)
major general complications (0–10%)
non-unions (<5%)
Surgery for AS is prone
to complications
Theseinterventionsarerelatedtoalongoperativetime,highlossofbloodanda
high rate of peri- and postoperative complications. Therefore, indications need
to be discussed on an individual basis and patients have to be consulted exten-
sively.
Recapitulation
Epidemiology.
Ankylosing spondylitis (AS) is a sys-
temic seronegative inflammatory rheumatic disor-
der belonging to the group of spondyloarthritis.
AS is associated with sacroiliitis and inflammatory
alteration at the axial skeleton. The male:female ra-
tio is about 2–7:1. Prevalence estimates vary be-
tween 0.2 and 1.2/100000. The peak age of onset is
15– 35 years. The diagnosis is delayed by up to
10 years, because of its insidious nature.
Pathogenesis. The pathogenesis is still unclear.
There is increasing evidence that AS is genetically

determined. AS has a strong association with HLA-
B27 and 90 % of all patients are HLA-B27 positive.
However, 80–90 % of all HLA-B27 carriers do not de-
velop AS. It is therefore widely assumed that addi-
tional genetic factors are involved. An infection-
triggered onset has recently been added to the ex-
isting hypothesis. This concept involves a preced-
ing bacterial infection with subsequent autoim-
mune responses. The pathological changes of the
vertebral column due to AS occur in three consecu-
tive stages: inflammation, proliferation and anky-
losis.
Clinical presentation. Patient complaints are non-
specific and difficult to distinguish from general
chronic back pain. Cardinal symptoms are inflam-
matory back pain, typical arthritis pain (pain at
night and stiffness in the morning), progressive
spinal stiffness and the inability to look straight
ahead. Additional symptoms are enthesis, uveitis,
pulmonary, cardial and bowel inflammation as well
as reduced chest expansion.
Diagnostic work-up. Early diagnosis of AS can be
difficult due to unspecific symptoms and diagnos-
tic findings of the spinal column. In the case of sus-
picion of AS, the diagnosis should be enforced. The
diagnostic work-up includes a thorough clinical ex-
amination, laboratory investigations (infection pa-
rameter, HLA-B27) and imaging studies. The goal is
todetectASintheearlydiseasesoastocommence
therapy in good time. In the early disease stage,

MRI is the state-of-the-art diagnostic tool. Charac-
teristic findings on MRI suggestive of AS are discitis,
erosions with zones of subchondral sclerosis with-
out increased signal after use of a contrast agent,
periarticular fat accumulation and syndesmophy-
tes. Alternatively, a bone scan can be of further di-
agnostic use. Radiographs and computed tomog-
raphy are suitable tools for monitoring chronic in-
flammatory progression. Furthermore the CT can
be utilized for preoperative planning. Following a
trauma and suspicion of lesion or fracture radio-
graphs, CT and MRI of the whole spine should be
performed.
1080 Section Tumors and Inflammation
Non-operative treatment. The non-operative phar-
macological therapy is the mainstay of care in con-
junction with physical exercises. Goal of the treat-
ment is the reduction of clinical symptoms, inflamma-
tion and delay of disease. The pharmacological ther-
apy includes non-selective and selective cyclooxyge-
nase (COX) inhibitors (NSAIDs), analgesics, disease
modifying antirheumatic drugs (e.g. sulfasalazine,
methotrexate) and TNF- inhibitors. Physiotherapy
and patient education are in parallel to medical treat-
ment cornerstones of AS therapy.
Operative treatment. Surgery is of value when con-
servative therapy fails, i.e., in the case of massive
kyphotic deformity or severe pain. Absolute indica-
tions forsurgeryareunstablespinalfractures,kypho-
sis-related progressive myelopathy and progressive

spondylodiscitis. Surgical correction in AS patients is
prone to a high peri- and postoperative complication
rate (such as neurological deficits, deep wound infec-
tions, failure of implants). However, the morbidity
and mortality rate can be decreased by careful surgi-
cal planning, new operating techniques, new im-
plants and improved intensive care. An important
aspect is the perioperative anesthesia. Patient posi-
tioning and intubation are often very difficult due to
kyphotic deformation. Intraoperative neuromonito-
ring is nowadays regarded as indispensable for a safe
deformity correction.
The ultimate goal of surgical techniques of osteo-
tomies is to rebalance the spine and correct the
chin-brow angle to an extent that the patient is
again able to look straight ahead. The most com-
mon technique is a closing wedge osteotomy in
the lumbar spine. The underlying concept is to
achieve a monosegmental extension while keeping
the anterior longitudinal ligament intact. The aim
of multisegmental posterior wedge osteotomy is
to address deformities predominantly located in
thethoracicspineandtoallowforaharmonic
bending of the spine. Four to six thoracic or lumbar
levels can osteotomized depending on the extent
and location of the spinal deformity.
Corrections at the level of the cervical spine are
performed at the C7/T1 level. The procedure of
choice is a closing or opening wedge osteotomy in
combination with an instrumented fusion. Cervical

spine surgery in AS appears to have a fairly good
clinical outcome, although it is a very demanding
operational procedure with a potentially high risk
of neurological injuries.
Fractures in AS patients can already appear after
minimal trauma and are often overlooked. Most
often, fractures appear in the thoracic spine and are
frequently unstable because they involve the ante-
rior and posterior spinal column. In 30 –75 % of cases
there is an association of severe neurological deficits.
In contrast to common fractures, however, the stabili-
zation should be long rather than short because of
the risk of a secondary kyphotic deformity.
Key Articles
van Royen BJ (1995) Closing-wedge posterior osteotomy for ankylosing spondylitis.
Partial corpectomy and transpedicular fixation in 22 cases. J Bone Joint Surg Br 77:
117 – 121
This retrospective study with closing wedge osteotomy at lumbar level L4 shows that this
surgical procedure is effective in addressing the kyphotic deformity.
Murrey DB (2002) Transpedicular decompression and pedicle subtraction osteotomy
(eggshell procedure): a retrospective review of 59 patients. Spine 27(21):2338 – 45
The eggshell procedure was described and analyzed retrospectively in 59 patients with
deformity (n=37) and tumor or infection (n = 22). This surgical procedure is safe and
predictable for complex spine deformities.
Hehne HJ (1990) Polysegme ntal lumbar osteotomies and transpedicled fixation for cor-
rection of long-curved kyphotic deformities in ankylosing spondylitis. Report on 177
cases. Clin Orthop Relat Res 258:49 – 55
This is a retrospective study with a high number of polysegmental lumbar osteotomies in
patients with AS. The authors describe surgery procedure, correction of spine postopera-
tively up to 18 months follow-up and associated complications.

Urist MR (1958) Osteotomy of the cervical spine; report of a case of ankylosing rheuma-
toid spondylitis. J Bone Joint Surg Am 40A:833 – 43
Classic article on the cervical opening wedge osteotomy for AS.
Ankylosing Spondylitis Chapter 38 1081
Smith-Petersen M, Larson C, Aufranc O (1945) Osteo tom y of the spine for correction of
flexion deformity in rheumatoid arthritis. J Bone Joint Surg Br 27:1–11
Classic article on an opening wedge osteotomy in the thoracolumbar spine and V-shaped
thoracic osteotomies for AS.
References
1. Amor B, Santos RS, Nahal R, Listrat V, Dougados M (1994) Predictive factors for the long-
term outcome of spondyloarthropathies. J Rheumatol 21:1883–7
2. Andersson O (1937) Röntgenbilden vid spondylarthritis ankylopoetica. Nord Med Tidskr
14:200
3. Appel H, Kuhne M, Spiekermann S, Ebhardt H, Grozdanovic Z, Kohler D, Dreimann M,
Hempfing A, Rudwaleit M, Stein H, Metz-Stavenhagen P, Sieper J, Loddenkemper C (2006)
Immunohistologic analysis of zygapophyseal joints in patients with ankylosing spondylitis.
Arthritis Rheum 54:2845–51
4. Apple DF, Jr, Anson C (1995) Spinal cord injury occurring in patients with ankylosing spon-
dylitis: a multicenter study. Orthopedics 18:1005–11
5. Aufdermaur M (1989) Pathogenesis of square bodies in ankylosing spondylitis. Ann Rheum
Dis 48:628–31
6. Baek HJ, Kang SW, Lee YJ, Shin KC, Lee EB, Yoo CD, Song YW (2005) Osteopenia in men
with mild and severe ankylosing spondylitis. Rheumatol Int 26:30–4
7. Baraliakos X, Hermann KG, Landewe R, Listing J, Golder W, Brandt J, Rudwaleit M, Bollow
M, Sieper J, van der Heijde D, Braun J (2005) Assessment of acute spinal inflammation in
patients with ankylosing spondylitis by magnetic resonance imaging: a comparison
between contrast enhanced T1 and short tau inversion recovery (STIR) sequences. Ann
Rheum Dis 64:1141–4
8. Baraliakos X, Landewe R, Hermann KG, Listing J, Golder W, Brandt J, Rudwaleit M, Bollow
M, Sieper J, van der Heijde D, Braun J (2005) Inflammation in ankylosing spondylitis: a sys-

tematic description of the extent and frequency of acute spinal changes using magnetic res-
onance imaging. Ann Rheum Dis 64:730–4
9. Bechterew W (1893) Steifigkeit der Wirbelsäule und ihre Verkrümmung als besondere
Erkankungsform. Neurol Centralblatt 12:426– 434
10. Bernd L, Blasius K, Lukoschek M (1992) [Spinal fractures in ankylosing spondylitis]. Z
Orthop Ihre Grenzgeb 130:59–63
11. Boachie-Adjei O (2006) Role and technique of eggshell osteotomies and vertebral column
resections in the treatment of fixed sagittal imbalance. Instr Course Lect 55:583–9
12. Boonen A (2006) A review of work-participation, cost-of-illness and cost-effectiveness
studies in ankylosing spondylitis. Nat Clin Pract Rheumatol 2:546–53
13. Boulos P, Dougados M, Macleod SM, Hunsche E (2005) Pharmacological treatment of anky-
losing spondylitis: a systematic review. Drugs 65:2111–27
14. Bradford DS, Schumacher WL, Lonstein JE, Winter RB (1987)Ankylosing spondylitis: expe-
rience in surgical management of 21 patients. Spine 12:238–43
15.
BraunJ,BaraliakosX, Godolias G, Bohm H (2005)Therapyof ankylosing spondylitis – areview.
Part I: Conventional medical treatment and surgical therapy. Scand J Rheumatol 34:97–108
16. Braun J, Baraliakos X, Golder W, Brandt J, Rudwaleit M, Listing J, Bollow M, Sieper J, Van
Der Heijde D (2003) Magnetic resonance imaging examinations of the spine in patients with
ankylosing spondylitis, before and after successful therapy with infliximab: evaluation of a
new scoring system. Arthritis Rheum 48:1126–36
17. Braun J, Baraliakos X, Golder W, Hermann KG, Listing J, Brandt J, Rudwaleit M, Zuehlsdorf
S, Bollow M, Sieper J, van der Heijde D (2004) Analysing chronic spinal changes in ankylos-
ing spondylitis: a systematic comparison of conventional x rays with magnetic resonance
imaging using established and new scoring systems. Ann Rheum Dis 63:1046–55
18. Braun J, Bollow M, Neure L, Seipelt E, Seyrekbasan F, Herbst H, Eggens U, Distler A, Sieper
J (1995) Use of immunohistologic and in situ hybridization techniques in the examination
of sacroiliac joint biopsy specimens from patients with ankylosing spondylitis. Arthritis
Rheum 38:499–505
19. Braun J, Sieper J (2007) Ankylosing spondylitis. Lancet 369:1379–90

20. Braun J, van der Heijde D (2002) Imaging and scoring in ankylosing spondylitis. Best Pract
Res Clin Rheumatol 16:573–604
21. Brophy S, Calin A (2001) Ankylosing spondylitis: interaction between genes, joints, age at
onset, and disease expression. J Rheumatol 28:2283–8
22. Brophy S, Mackay K, Al-Saidi A, Taylor G, Calin A (2002) The natural history of ankylosing
spondylitis as defined by radiological progression. J Rheumatol 29:1236–43
1082 Section Tumors and Inflammation
23. Brown MA, Edwards S, Hoyle E, Campbell S, Laval S, Daly AK, Pile KD, Calin A, Ebringer A,
Weeks DE, Wordsworth BP (2000) Polymorphisms of the CYP2D6 gene increase susceptibil-
ity to ankylosing spondylitis. Hum Mol Genet 9:1563–6
24. BrownMA, Laval SH, Brophy S, Calin A (2000) Recurrence risk modelling of the genetic sus-
ceptibility to ankylosing spondylitis. Ann Rheum Dis 59:883–6
25. Calin A, Elswood J (1989) Retrospective analysis of 376 irradiated patients with ankylosing
spondylitis and nonirradiated controls. J Rheumatol 16:1443–5
26. Camargo FP, Cordeiro EN, Napoli MM (1986) Corrective osteotomy of the spine in ankylos-
ing spondylitis. Experience with 66 cases. Clin Orthop Relat Res:157–67
27. Cawley MI, Chalmers TM, Kellgren JH, Ball J (1972) Destructive lesions of vertebral bodies
in ankylosing spondylitis. Ann Rheum Dis 31:345–58
28. Chang KW, Chen YY, Lin CC, Hsu HL, Pai KC (2005) Closing wedge osteotomy versus open-
ing wedge osteotomy in ankylosing spondylitis with thoracolumbar kyphotic deformity.
Spine 30:1584–93
29. Chang KW, Tu MY, Huang HH, Chen HC, Chen YY, Lin CC (2006) Posterior correction and
fixation without anterior fusion for pseudoarthrosis with kyphotic deformity in ankylosing
spondylitis. Spine 31:E408–13
30. Charlesworth CH, Savy LE, Stevens J, Twomey B, Mitchell R (1996) MRI demonstration of
arachnoiditis in cauda equina syndrome of ankylosing spondylitis. Neuroradiology 38:
462–5
31. Dagfinrud H, Kvien TK, Hagen KB (2004) Physiotherapy interventions for ankylosing spon-
dylitis. Cochrane Database Syst Rev:CD002822
32. Dagfinrud H, Kvien TK, Hagen KB (2005) The Cochrane review of physiotherapy interven-

tions for ankylosing spondylitis. J Rheumatol 32:1899–906
33. Danisa OA, Turner D, Richardson WJ (2000) Surgical correction of lumbar kyphotic defor-
mity: posterior reduction “eggshell” osteotomy. J Neurosurg 92:50–6
34. Detwiler KN, Loftus CM, Godersky JC, Menezes AH (1990) Management of cervical spine
injuries in patients with ankylosing spondylitis. J Neurosurg 72:210–5
35. Dougados M, Gueguen A, Nakache JP, Velicitat P, Zeidler H, Veys E, Calin A (1999) Clinical
relevance of C-reactive protein in axial involvement of ankylosing spondylitis. J Rheumatol
26:971–4
36. Dougados M, van der Heijde D (2002) Ankylosing spondylitis: how should the disease be
assessed? Best Pract Res Clin Rheumatol 16:605–18
37. Eksioglu E, Bal A, Gulec B, Aydog E, Cakci A (2006) Assessment of shoulder involvement
and disability in patients with ankylosing spondylitis. Rheumatol Int 27:169 –73
38. Emery RJ, Ho EK, Leong JC (1991) The shoulder girdle in ankylosing spondylitis. J Bone
Joint Surg Am 73:1526–31
39. Fang D, Leong JC, Ho EK, Chan FL, Chow SP (1988) Spinal pseudarthrosis in ankylosing
spondylitis. Clinicopathological correlation and the results of anterior spinal fusion. J Bone
Joint Surg Br 70:443– 7
40. Feldtkeller E, Vosse D, Geusens P, van der Linden S (2006) Prevalence and annual incidence
of vertebral fractures in patients with ankylosing spondylitis. Rheumatol Int 26:234–9
41. Frauendorf E, von Goessel H, May E, Marker-Hermann E (2003) HLA-B27-restricted T cells
from patients with ankylosing spondylitis recognize peptides from B*2705 that are similar
to bacteria-derived peptides. Clin Exp Immunol 134:351–9
42. Graham B, Van Peteghem PK (1989) Fractures of the spine in ankylosing spondylitis. Diag-
nosis, treatment, and complications. Spine 14:803–7
43. Gran JT, Skomsvoll JF (1997) The outcome of ankylosing spondylitis: a study of 100 patients.
Br J Rheumatol 36:766–71
44. Grundy PL, Gill SS (1998) Odontoid process and C1-C2 corrective osteotomy through a pos-
terior approach: technical case report. Neurosurgery 43:1483–6; discussion 1486–7
45. Halm H, Metz-Stavenhagen P, Zielke K (1995) Results of surgical correction of kyphotic
deformities of the spine in ankylosing spondylitis on the basis of the modified arthritis

impact measurement scales. Spine 20:1612–9
46. Harrop JS, Sharan A, Anderson G, Hillibrand AS, Albert TJ, Flanders A, Vaccaro AR (2005)
Failureofstandardimagingtodetectacervicalfractureinapatientwithankylosingspon-
dylitis. Spine 30:E417–9
47. Hehne HJ, Zielke K, Bohm H (1990) Polysegmental lumbar osteotomies and transpedicled
fixation for correction of long-curved kyphotic deformities in ankylosing spondylitis.
Report on 177 cases. Clin Orthop Relat Res:49–55
48. Inanc N, Atagunduz P, Sen F, Biren T, Turoglu HT, Direskeneli H (2005) The investigation of
sacroiliitis with different imaging techniques in spondyloarthropathies. Rheumatol Int
25:591–4
49. Jaakkola E, Herzberg I, Laiho K, Barnardo MC, Pointon JJ, Kauppi M, Kaarela K, Tuomi-
lehto-Wolf E, Tuomilehto J, Wordsworth BP, Brown MA (2006) Finnish HLA studies confirm
the increased risk conferred by HLA-B27 homozygosity in ankylosing spondylitis. Ann
Rheum Dis 65:775–80
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