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ORIGINAL ARTICLE
Posterior thoracic osteotomies
Ferran Pellise • Alba Vila-Casademunt •
European Spine Study Group (ESSG)
Received: 6 March 2014 / Accepted: 9 April 2014
� Springer-Verlag France 2014
Abstract Spinal osteotomies are used to treat partially
flexible and fixed deformities. Fixed thoracic spinal
deformities have been traditionally treated with anterior
release and posterior correction with fusion. In recent
decades, it has been shown that posterior-only osteotomies
might be sufficient to achieve proper deformity correction
with lower complication rates than with combined anterior
and posterior procedures. Different types of osteotomies
have been described to treat spinal deformities through a
single posterior approach. These include posterior column
osteotomies such as the Smith-Petersen osteotomy and the
Ponte osteotomy, and three-column osteotomies such as the
pedicle subtraction osteotomy, the posterior vertebral col-
umn resection and the posterior vertebral column decan-
cellation. In general, three-column osteotomies are most
commonly performed in the lumbar spine, where the vast
majority of reports have focused on. They can also be
performed in the thoracic spine in the setting of rigid
thoracic deformity. A progressive increase in complica-
tions has been reported with more aggressive osteotomies.
The aim of this article was to describe the most common
posterior spinal osteotomies used to treat adult thoracic
spinal deformities, with special emphasis on the technical
aspects, complications and outcomes, based on current
publications and European Spine Study Group (ESSG)
data.
Keywords Thoracic spine osteotomy � Posterior column
osteotomy � Pedicle subtraction osteotomy � Posterior
vertebral column resection � Spinal osteotomy
complications
Introduction
Normal alignment of the thoracic spine is straight in the
coronal plane and kyphotic in the sagittal plane. Studies
using standing lateral radiographs of the entire spine have
reported values for both segmental and total kyphosis and
lordosis in an asymptomatic population [1–9]. It is well
known that each person has their own physiological upright
standing posture and individual pattern of spinopelvic and
sagittal alignment [9]. Although a ‘‘normal’’ mean value
cannot be determined, some authors describe normal tho-
racic kyphosis as ranging from 20� to 40� and normal lumbar
lordosis as ranging from 30� to 80� and always being pro-
portionally balanced. With normal ageing, these physiolog-
ical curves change: thoracic kyphosis increases and lumbar
lordosis decreases, resulting in an anterior shift of the C7
plumb line [8, 10, 11]. The most common aetiologies of adult
spinal deformities in the thoracic region are idiopathic,
congenital, post-traumatic or inflammatory [12–15].
Surgical strategies for treating spinal deformities are
determined based on severity, flexibility, apex location and
deformity shape [16]. Osteotomies are currently used to
treat partially flexible and fixed deformities. Thoracic
deformities with an apex at the cord level are more tech-
nically challenging than lumbar deformities with an apex at
the cauda equina level due to the risk of spinal cord
compromise. Osteotomies should be performed using
intraoperative neuromonitoring. Long, sweeping, rounded
deformities are easier to treat with multiple osteotomies.
F. Pellise (&)
Unitat de Raquis, servei de cirurgia ortopedica i traumatologia,
Hospital Universitari Vall d’Hebron, Passeig Vall d’Hebron
119-129, 08035 Barcelona, Spain
e-mail: 24361fpu@comb.cat
A. Vila-Casademunt
Vall d’Hebron Institut de Recerca, Passeig Vall d’Hebron
119-129, 08035 Barcelona, Spain
123
Eur J Orthop Surg Traumatol
DOI 10.1007/s00590-014-1463-7
Surgical correction can be performed on multiple spinal
segments. Short, angular deformities require a more
aggressive approach in which surgical correction is con-
centrated in a few spinal segments.
Fixed thoracic spinal deformities have been traditionally
treated with anterior release and posterior correction with
fusion [17, 18]. In recent decades, different authors have
shown that posterior-only osteotomies with instrumented
fusion is sufficient to achieve proper deformity correction
with lower complication rates than with combined anterior
and posterior procedures [19, 20].
Different types of osteotomies have been described to
treat fixed or partially flexible spinal deformities through a
single posterior approach. These include posterior column
osteotomies such as the Smith-Petersen osteotomy (SPO)
and the Ponte osteotomy, and three-column osteotomies
such as the pedicle subtraction osteotomy (PSO), the pos-
terior vertebral column resection (PVCR) and the posterior
vertebral column decancellation (PVCD). The variable use
of the terminology to define osteotomy type has led to a
more systematic grading of the complexity of posterior
spinal osteotomies [21]. There is a paucity of information
describing the use of osteotomies to correct adult thoracic
spinal deformities.
In July 2010, a group of European surgeons founded the
European Spine Study Group (ESSG) to evaluate clinical
outcomes for conservative and surgical adult spinal
deformity (ASD) treatment. To do this, the ESSG members
share a comprehensive prospective database into which
data from all consecutive patients meeting pre-established
inclusion criteria and signing informed consent is uploa-
ded. ESSG inclusion criteria are age 18 or over at the time
of surgery or initial consultation, having a spinal coronal
curvature of C20� or a sagittal vertical axis (SVA) of
[5 cm or a pelvic tilt of [25� or thoracic kyphosis of
[60�. By January 2014, the ESSG database included a
total of 897 patients (mean age 49.9 years, 241 females)
from six different European sites: the Ankara Spine Center
in Ankara (Turkey), the Vall d’Hebron Hospital in Barce-
lona (Spain), the CHU de Bordeaux university hospital
centre in Bordeaux (France), the Acibadem Maslak Hos-
pital in Istanbul (Turkey), La Paz University Hospital in
Madrid (Spain) and the Schulthess Klinik in Zurich
(Switzerland). Of these 897 patients, 586 were not surgical
candidates and 311 had undergone surgery. Spinal osteot-
omies had been performed on 145 patients. Thoracic os-
teotomies had been performed on 33 (22.7 %) patients
(mean age 42.1 years, 18 women).
The aim of our paper was to describe the most common
posterior spinal osteotomies used to treat adult thoracic
spinal deformities, with special emphasis on the technical
aspects, complications and outcomes, based on current
publications and ESSG data.
Schwab Grade 2, Smith-Petersen osteotomy (SPO)/
Ponte osteotomy
In a Schwab Grade 2 osteotomy, both inferior and superior
facets of an articulation at a given spinal segment are
resected, as well as the ligamentum flavum; other posterior
elements of the vertebra including the lamina, or the spi-
nous processes may also be resected [21]. The Smith-Pet-
ersen osteotomy can be considered a Schwab Grade 2
osteotomy. In most cases, an SPO is described as an
osteotomy in which the posterior column is resected
between the facet joints at one or more levels to create
additional lordosis [16]. SPOs were first described in 1945
and were used principally for ankylosing spondylitis [22–
24]. Correction was obtained by rupturing and opening the
anterior column. Schwab Grade 2 osteotomies incorporate
resection of bone beyond what was originally described by
Smith-Petersen. The Ponte procedure is also considered a
Schwab Grade 2 since it corresponds to the resection of
multiple facets joints and spinous processes and involves
substantial bone and ligament resection for deformity
correction. It was first described by Alberto Ponte in 1984
to treat flexible Scheuermann’s kyphosis [25].
In all of these osteotomies, the middle and anterior
columns are such that the anterior column opens through
the disc space when closing the osteotomy posteriorly to
correct kyphotic deformities or laterally to correct scoliotic
deformities. It is therefore necessary to have a potentially
mobile disc space to achieve correction with an SPO or
Schwab Grade 2 osteotomy. This is usually done at mul-
tiple levels to create gradual correction in a large number
of spinal segments.
The ideal candidates for multiple Grade 2 osteotomies
are patients who have long, sweeping, rounded deformities
with some anterior column mobility, such as Scheuer-
mann’s kyphosis and idiopathic thoracic scoliosis [16]
(Figs. 1, 2). Schwab Grade 2 SPOs may provide 5�–10�lordosis or 1� per millimetre of correction [16]. The extent
of correction will be proportional to and depend on disc
space or anterior column mobility. Thirteen (13) ESSG
patients underwent multiple Schwab Grade 2 thoracic
SPOs for the following aetiologies: Scheuermann’s ky-
phosis (5), idiopathic kyphoscoliosis (6), proximal junc-
tional kyphosis (1) and syndromic kyphoscoliosis (1). They
experienced a mean correction of 7� per segment with an
overall deformity correction rate of 43.8 %. Schwab Grade
2 SPOs can also be used concurrently with more focused,
aggressive three-column osteotomies to obtain some addi-
tional correction.
Surgical technique starts with complete removal of the
spinous process and inferior facets of the superior vertebra.
Careful opening of the epidural space is followed by a
complete flavectomy and the bilateral removal of the
Eur J Orthop Surg Traumatol
123
superior articular facets. In kyphotic deformities, the spinal
cord will be located anteriorly and subsequently, SPOs can
be performed easily. In scoliotic deformities, the cord will
be located in the concavity of the curve and care should be
taken when removing the concave articular facets. Concave
pedicle screws may be inserted before or after completing
the osteotomy. If inserted before, the screw head may
hinder concave facet joint removal in scoliotic cases. If
inserted once, the osteotomy is completed, pedicle screws
can be placed under direct visual control, but care should
be taken to protect neural structures during screw insertion.
In kyphotic deformities, correction is obtained by closing
the posterior column at the osteotomy sites. This can be
done through sequential segmental compression and pos-
terior osteotomy closure or by thoracic spine extension
with a cantilever manoeuver, or with a combination of
Fig. 1 Scheuermann’s, pre-operative and post-operative X-rays. PSFI T2-L1 with multiple T5–T12 SPOs
Fig. 2 Idiopathic scoliosis, pre-operative and post-operative X-rays. PSFI T2-L1 with multiple T6–T10 SPOs
Eur J Orthop Surg Traumatol
123
both. Scoliotic deformity correction is generally obtained
by closing, compressing or shortening the convexity and
opening the concavity. This can be done using periapical
derotation, translation and compression–distraction
manoeuvres.
The Morbidity & Mortality (M&M) Committee of the
Scoliosis Research Society (SRS) studied and reported
short-term complications associated with the surgical
treatment of thoracolumbar fixed sagittal plane deformities
[26]. Osteotomies were performed in 402 of the 578 ana-
lysed cases and included 135 SPOs, 215 PSOs and 18
VCRs. Cases with thoracic osteotomies were not specifi-
cally identified. The SPO procedure complication rate was
28.1 %, and the most common complications were dural
tears (6.7 %). Neurological deficits developed in 3.7 %.
These data were comparable with the results extracted from
the Cho et al. report [27], in which they reported an SPO
complication rate of 36.6 % and a new neurological deficit
rate of 3.3 %. Our data on 13 patients with Grade 2 tho-
racic osteotomies demonstrated two transient, minor sen-
sory deficits and one posterior arch fracture without further
consequences. No other osteotomy-related complications
were identified.
Schwab Grade 3, thoracic pedicle subtraction
osteotomy (TPSO)
A pedicle subtraction osteotomy (PSO) is a V-shaped
resection through the posterior structures, pedicles and
vertebral body. The hinge point is located anteriorly. In
most cases, the resection is performed entirely through
bone [16]. This type of osteotomy is categorised as Schwab
Grade 3. With this technique, no anterior column length-
ening is performed. A variant of this involves resecting the
disc space above, but this variation would then be con-
sidered a Schwab Grade 4 osteotomy. Michele and Krueger
[28] or Thomasen [29] have been alternately credited with
developing PSO.
Although PSO is a commonly used and reported tech-
nique for lumbar flat back syndrome, it can also be used for
thoracic spine deformities [12–15, 30]. The ideal candi-
dates for a PSO are patients with fixed sagittal (Fig. 3a)
sharp angular deformity, such as what is seen in cases of
post-traumatic kyphosis [16]. Severe, symptomatic roun-
ded and rigid thoracic kyphosis ([80�), for which poten-
tially less-risky osteotomies such as SPOs are not feasible
due to the lack of sagittal curve flexibility, may also be a
good indication for thoracic PSO [12]. The unilateral PSOs
commonly used to treat hemivertebrae in paediatric
patients are seldom used in adults, but could be used to
treat coronal plane deformities. O’Shaughnessy et al. [12]
reported on 15 patients with proximal junctional kyphosis
(n = 5), ankylosing spondylitis (n = 3), post-traumatic
kyphosis (n = 2), idiopathic kyphoscoliosis (n = 3), post-
laminectomy kyphosis (n = 1) and degenerative kypho-
scoliosis (n = 1) who underwent 25 thoracic PSOs. Thir-
teen patients underwent thoracic PSO only to correct a
sagittal deformity and two patients underwent PSO com-
bined with another three-column osteotomy. Yang et al.
[13] reported on seven patients who underwent thoracic
PSO to correct degenerative kyphoscoliosis (5), late-onset
adolescent idiopathic scoliosis (1) and ankylosing spon-
dylitis (1). Lafage et al. [15] analysed eighteen (18)
patients who underwent thoracic PSO. Lehmer et al. [30]
reported the results of four distal thoracic PSOs as part of a
larger series of primarily lumbar PSOs. The ESSG database
includes nine patients who underwent nine thoracic PSOs
to treat thoracolumbar Scheuermann’s kyphosis (4), post-
traumatic kyphosis (4) and idiopathic kyphoscoliosis (1). In
eight cases, we performed a single PSO, and in one patient
with Scheuermann’s kyphosis, the thoracic PSO was
associated with six SPOs (Fig. 3b).
PSOs are typically performed in the apical region of the
deformity [12]. If a PSO is performed in the thoracic spine,
it is important to refrain from retracting the thecal sac and
to resect portions of ribs on both sides in an effort to
approach the vertebral body more laterally [16]. The
proximal 2-to-3 cm of the ribs that articulate with the discs
above and below the planned PSO are exposed and cut. The
thoracic nerve root may or may not be cut. The lateral
vertebral body wall is bilaterally dissected. A posterior,
V-shaped resection that includes the pedicles and part of
the vertebral body is performed. The medial aspect of the
pedicles and the posterior vertebral body wall are preserved
until the end. The final structure resected is the posterior
vertebral body wall. This is performed using an impaction
technique [12]. When closing a PSO, it is necessary to
observe the spine for subluxation. The use of temporary
rods and progressive correction through sequential rod
exchange are advisable [31]. Safe posterior osteotomy
closure should be performed without excessive dural
kinking. Twenty (20) to 25 mm of posterior laminar clo-
sure may be tolerated in a thoracic PSO without adverse
neurological consequences [12]. It is advisable to keep the
canal centrally enlarged when performing a thoracic PSO
[16].
In general, lumbar and thoracic PSOs have a
39.1–58.5 % complication rate [26, 27]. Dural tears, new
neurological deficits and pseudoarthrosis are the most
commonly reported complications. Procedures with a PSO
have been found to have almost twice the rate of new
neurological deficits as procedures with an SPO (7 vs
3.7 %). O’Shaughnessy et al. [12] reported on three tho-
racic PSOs out of 25 that were associated with early
structural complications, including two cases of vertebral
Eur J Orthop Surg Traumatol
123
collapse and one case of segmental translation associated
with osteotomy closure. In the patient who experienced
segmental translation, there was a decline in intraoperative
somatosensory-evoked potentials at the time of the oste-
otomy closure. This was the only case of intraoperative
neurophysiological change. Yang et al. [13] reported one
surgical complication and one late-onset complication
requiring corrective surgery in the thoracic PSO group.
However, none of them were related to the resection
technique. None of the ESSG patients undergoing thoracic
PSO sustained complications directly related to the
osteotomy.
Lumbar PSOs are associated with significant improve-
ments in local, segmental and global measures of sagittal
balance, whereas thoracic PSOs are only associated with
local improvement and fail to produce the same degree of
segmental or global correction [13]. A lumbar PSO will
produce approximately 20�–35� of lordosis. A thoracic
PSO will produce approximately 10�–30� of lordosis [12,
13, 16, 30, 32]. Our patients achieved a 73.9 % overall
deformity correction rate, with a mean 26.6� correction per
thoracic PSO. The extent of thoracic PSO correction may
be dependent on the region in which the osteotomy is
performed [12]. As one moves from distal to proximal,
vertebral bodies become shorter and more triangulated in
the axial plane. Shorter vertebral bodies may offer less
corrective potential than longer ones. O’Shaughnessy et al.
[12] recommended PVCR for corrections between T2 and
T10. PVCR was found to be better than PSO in terms of
stability during closure and offering a more robust and
predictable amount of correction for a single osteotomy. In
a PSO, excessive posterior shortening may result in buck-
ling of the dura and spinal cord. The more posteriorly
located the hinge is, the lesser the need is for spinal cord
shortening, and thus, the safer the correction is. PVCR has
a more posterior hinge and provides correction with less
posterior shortening. In post-traumatic cases, an extended
PSO or Schwab Grade 4 osteotomy is very frequently
needed to ensure good bone contact and anterior column
fusion. In cases where most of the vertebral body has
already collapsed due to the fracture, standard PVCR or
unilateral PVCR preserving the posterior wall and half
posterior arch (described later) may be a better option than
PSO. Lafage et al. [15] compared the correction obtained in
18 thoracic PSOs and 23 thoracic PVCRs and found no
significant difference. Mean focal sagittal correction was
14.4� in all patients and 20.8� in patients with primarily
sagittal or multiplanar deformities. The mean correction
obtained with PSO was 12.8� (SD 14.4�) and with PVCR
was 15.6� (SD 14.9�).
Schwab Grade 5 and Grade 6, thoracic posterior
vertebral column resection (PVCR)
Vertebral column resection (VCR) is an osteotomy of all
three columns of the spine and is normally reserved for
severe rigid spinal deformities. VCRs provide the transla-
tion and shortening necessary to correct multiplanar
deformities [31]. VCR refers to completely resecting one or
more vertebrae, including posterior elements, pedicles and
the entire vertebral body with the discs above and below.
Reconstruction of both the posterior, and frequently, the
anterior column is usually necessary with a VCR. VCR was
initially suggested for tumours. This type of resection can
be included within Schwab osteotomy Grade 5. When more
than one vertebral body is resected, it may be included in
Grade 6. Despite the satisfactory outcomes of the two-stage
anterior–posterior technique, several series of patients have
been treated with posterior-only VCR (PVCR) in recent
years [20]. The osteotomy is usually performed at the apex
of the deformity to increase the effectiveness of the
resection. Despite both being circumferential posterior
osteotomies, the primary difference between a PVCR and a
Fig. 3 a Fixed Scheuermann’s, pre-operative Fulcrum X-ray. b Fixed Scheuermann’s, pre-operative and post-operative X-rays. PSFI T2-Iliac
with T10-L4 SPO and T12 PSO
Eur J Orthop Surg Traumatol
123
PSO is that during a PVCR, both the spinal cord and the
impinging wedge fragment are identified under lateral direct
vision, thus confirming complete decompression. Therefore,
PVCR can be safely performed at the level of the cord. This
provides the powerful translation and shortening necessary to
correct extensive rigid deformities. VCR is a complete de-
stabilising spinal osteotomy, for which the amount of cor-
rection is only limited by the spinal cord. VCR indications
include severe, rigid biplanar deformities with coronal and
sagittal misalignment and sharp angular kyphosis [15, 20].
The majority of reports concerning thoracic PVCR include
paediatric patients [31]; few are focused on adult thoracic
PVCR [15]. Eleven patients in the ESSG database underwent
thoracic PVCR for idiopathic kyphoscoliosis (3), congenital
kyphoscoliosis (5), post-traumatic kyphosis (2) or Scheuer-
mann’s kyphosis (1) (Fig. 4a–c).
After typical midline posterior spinal exposure, seg-
mental instrumentation is performed. Vertebrae are then
instrumented both cephalad and caudally to the osteotomy
site. PVCR is performed through a bilateral costotrans-
versectomy. We recommend dissecting circumferentially
and exposing the anterior aspect of the spine as much as
possible while maintaining the spinal canal closed and the
cord protected. The transverse processes, head of the ribs
and proximal portion of the ribs are excised. Using the
lateral wall of the pedicles as guidance, the parietal pleura
is detached and reflected back from the anterior aspect of
the vertebral body, exposing both the apical and the
immediately adjacent vertebrae circumferentially until the
anterior surface of the vertebral body is palpable. The
sharper and more angular the thoracic kyphosis is, the
easier the circumferential exposure of the spine will be
through a posterior-only approach. A temporary rod is
placed. Following a total laminectomy and bilateral total
foraminal unroofing under direct visual control, the pedi-
cles and the lateral portion of the vertebral body are
Fig. 4 a Congenital scoliosis, pre-operative clinical photographs. b Congenital scoliosis, post-operative clinical photographs. c Congenital
scoliosis. Pre-operative and post-operative X-rays. PSFI T2-Iliac with T10-L4 SPO and T12 PSO
Eur J Orthop Surg Traumatol
123
removed. The vertebral body and discs are removed in a
piecemeal fashion, keeping a thin shell of posterior verte-
bral wall beneath the dural sac. This portion of the pos-
terior wall is the last portion of vertebrae to be removed. In
principle, the minimal amount of resection necessary for
safe, adequate correction of the deformity should be per-
formed. Deformities are corrected either with in situ rod
bending or the sequential exchange of temporary rods with
progressively less deformed pre-contouring [31]. The ver-
tebral column is initially shortened through compression.
The deformity is gradually corrected with repeated addi-
tional compression to shorten the vertebral column until the
exposed cord looks redundant. After correcting the defor-
mity, any residual anterior interbody gap should be filled
with a cage and bone graft to reconstruct anterior column
support and improve the chances of fusion [20]. We would
recommend using a final four-rod construct to avoid early
rod breakage in case bony healing is delayed. Cord pro-
tection should be considered if, after osteotomy closure, the
spinal cord is still the posterior-most spinal structure.
Protection can be provided with bone (rib or allograft) or
metal [33] (Fig. 5).
Papadopoulos et al. [31] reported intraoperative moni-
toring changes in 22 % of patients due to hypotension or
excessive cord manipulation [20]. All but one of these
patients returned to normal after appropriate manoeuvres.
Common strategies to avoid cord damage include main-
taining blood supply by preserving as many neurovascular
bundles as possible and avoiding hypotensive anaesthesia.
Excessive cord shortening may be dangerous. In an
experimental study, Kawahara et al. [34] demonstrate that
during acute spinal shortening, the spinal cord and dura
pass through three phases. Phase 1 is considered safe and
indicates that the vertebral segment is shortened by less
than one-third. There is no dural sac or spinal cord defor-
mity. In Phase 2, a warning stage, the vertebral segment is
shorted by one-third to two-thirds and is accompanied by
shrinking and buckling of the dural sac, but no spinal cord
deformity. In Phase 3, a dangerous stage, vertebral
shortening is in excess of two-thirds and is accompanied by
spinal cord deformity and compression of the buckled dura.
In Phase 3, cord damage is highly probable. Spinal cord
blood flow is markedly increased in Phases 1 and 2.
The SRS M&M reported an overall complication rate
for procedures with a VCR of 61.1 % [26]. Suk reported a
34.3 % complication rate in 70 spinal deformity patients
who had a total of 143 resected vertebrae (76 thoracic and
67 lumbar). The most serious complications were two
complete cord injuries. Kim et al. [35] reviewed 233
patients treated with PVCR and found an overall incidence
of complications of 40.3 %. Xie et al. [36] reported 46
intraoperative and post-operative complications in 18 out
of 28 patients receiving PVCR. There were five cases of
neurological complications including one case of late-onset
paralysis and four cases of thoracic nerve root pain, all of
which resolved during the early follow-up period. Non-
neurological complications occurred more often in ky-
phoscoliotic patients (41 complications). Eleven (11)
patients included in the ESSG database underwent thoracic
PVCR. We identified 19 complications, five of which were
considered major. Two patients suffered rod breakage that
required corrective surgery and one other patient experi-
enced unresolved proximal junctional kyphosis. Two
patients suffered three neurological complications, two of
which were transient and one of which ended up being
permanent paralysis. Overall reported deformity correction
obtained with PVCR ranges from 45 to 68 % [15, 20, 31,
35, 36]. Our patients achieved a mean deformity correction
of 67.6 %, 32.9� per osteotomy.
Other types of thoracic osteotomies
Posterior vertebral column decancellation (PVCD)
Wang [37] suggested a modified PVCR to reduce spinal
column instability, blood loss and excessive cord manip-
ulation. In PVCD, pedicles of apical vertebrae are enlarged
using a high-speed drill. Then, multilevel vertebral body
decancellation and residual disc removal are performed.
After vertebral body decancellation, the posterior elements
are removed. Deformity correction is obtained through
osteoclasis of the concave cortex and compression of the
convex cortex using posterior pedicle instrumentation. In
kyphotic deformities, anterior cortex osteoclasis is
achieved through gentle extension. Autogeneous bone graft
is then applied to fill gaps and ensure bony fusion. In most
cases, segmental vessel exposure is not needed. Wang
reported a mean of 2.2 decancelled vertebrae in 45 patients
with severe sharp angular spinal deformities (29 cases of
congenital kyphoscoliosis and 16 cases of Pott’s disease)
who underwent vertebral decancellation, and an average
Fig. 5 Metal cord protection
Eur J Orthop Surg Traumatol
123
post-operative kyphosis correction of 82.2�. All patients
showed evidence of solid fusion at the last follow-up.
There was a reported surgical complication rate of 17.8 %.
These complications included one case of CSF leak, one
case of deep wound infection, one case of epidural
haematoma and four cases of transient neurological
deficits.
Unilateral PVCR preserving posterior wall and half
posterior arch
In some cases, especially in elderly patients with post-
traumatic kyphosis in which deformity is due to vertebral
body collapse with some movement expected at the disc
level, circumferential reconstruction can be performed
through a unilateral costotransversectomy (Fig. 6). Once
the unilateral costotransversectomy approach is performed
and pedicle screws have been inserted proximally and
distally to the osteotomy site, the ipsilateral posterior arch
is removed exposing the dural sac and the ipsilateral nerve
roots. Ligation of the interfering nerve root is recom-
mended to safely mobilise the spinal cord and create
enough space for bony and soft tissue removal. A tempo-
rary rod is inserted contralaterally. The discs above and
below the resected vertebral bodies should be identified
and removed taking care not to damage the end-plates of
the adjacent vertebral bodies. The collapsed vertebral body
is gradually removed, preserving most of the posterior
wall. Under direct visual control, the anterior vertebral
body wall can be removed using a Kerrison rongeur. At this
stage, rod exchange is performed to progressively correct
the deformity. Anterior release is amplified until full cor-
rection is obtained. The anterior gap is then filled with a
cage and autologous bone to restore anterior column sup-
port and obtain interbody fusion. Compression is provided
to capture the cage and the ipsilateral rod is inserted.
Contralateral posterior arches are decorticated and the bone
graft added. This procedure can be done to reconstruct one
or more spinal segments (Fig. 7).
Conclusions
Spinal osteotomies are well known and highly effective
surgical techniques used to correct partially flexible and
rigid spinal deformities. The recent SRS M&M [26] report
Fig. 6 CT scan. Unilateral PVCR preserving posterior wall and half
posterior arch
Fig. 7 Post-traumatic kyphosis, pre-operative and post-operative X-rays
Eur J Orthop Surg Traumatol
123
clearly demonstrates a progressive increase in complica-
tions with more aggressive osteotomies. There is still very
limited data on thoracic three-column osteotomies in the
adult population. A careful case-by-case analysis of the
magnitude, location and flexibility of deformities is needed
to understand what type of osteotomy or combination of
osteotomies will accomplish various surgical goals. It is
essential to take into consideration the significantly higher
complication rates associated with osteotomies as well as
the relevance of patient characteristics such as age and
comorbidities in determining the best surgical strategy for
each case type and for each patient.
Acknowledgments We acknowledge DepuySynthes Spine for its
funding support.
Conflict of interest Dr. Pellise reports grants from Depuy Synthes
Spine, during the conduct of the study; grants and personal fees from
Depuy Synthes Spine, grants from K2 M, personal fees from Biomet,
outside the submitted work. Dr. Vila-Casademunt reports grants from
Depuy Synthes Spine, during the conduct of the study; grants from
Depuy Synthes Spine, outside the submitted work. Dr. (ESSG) reports
grants from Depuy Synthes Spine, during the conduct of the study;
grants from Depuy Synthes Spine, outside the submitted work.
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