We treated 12 patients with multilevel stenosis of the cervical canal after spondylosis or ossification of the posterior longitudinal ligament by an expansive open-door laminoplasty, stabilised by using an
Minimal clinically important differences (MCID)
in the scores of patient-reported outcome measures allow clinicians to
assess the outcome of intervention from the perspective of the patient.
There has been significant variation in their absolute values in
previous publications and a lack of consistency in their calculation. The purpose of this study was first, to establish whether these
values, following spinal surgery, vary depending on the surgical
intervention and their method of calculation and secondly, to assess
whether there is any correlation between the two external anchors
most frequently used to calculate the MCID. . We carried out a retrospective analysis of prospectively gathered
data of adult patients who underwent elective spinal surgery between
1994 and 2009. A total of 244 patients were included. There were
125 men and 119 women with a mean age of 54 years (16 to 84); the
mean follow-up was 62 months (6 to 199) The MCID was calculated
using three previously published methods. Our results show that the value of the MCID varies considerably
with the operation and its method of calculation. There was good
correlation between the two external
The aim of this study was to compare outcomes after growth-friendly treatment for early-onset scoliosis (EOS) between patients with skeletal dysplasias versus those with other syndromes. We retrospectively identified 20 patients with skeletal dysplasias and 292 with other syndromes (control group) who had completed surgical growth-friendly EOS treatment between 1 January 2000 and 31 December 2018. We compared radiological parameters, complications, and health-related quality of life (HRQoL) at mean follow-up of 8.6 years (SD 3.3) in the dysplasia group and 6.6 years (SD 2.6) in the control group.Aims
Methods
We compared decompression alone to decompression with fusion surgery for lumbar spinal stenosis, with or without degenerative spondylolisthesis (DS). The aim was to evaluate if five-year outcomes differed between the groups. The two-year results from the same trial revealed no differences. The Swedish Spinal Stenosis Study was a multicentre randomized controlled trial with recruitment from September 2006 to February 2012. A total of 247 patients with one- or two-level central lumbar spinal stenosis, stratified by the presence of DS, were randomized to decompression alone or decompression with fusion. The five-year Oswestry Disability Index (ODI) was the primary outcome. Secondary outcomes were the EuroQol five-dimension questionnaire (EQ-5D), visual analogue scales for back and leg pain, and patient-reported satisfaction, decreased pain, and increased walking distance. The reoperation rate was recorded.Aims
Methods
This study aimed, through bioinformatics analysis and in vitro experiment validation, to identify the key extracellular proteins of intervertebral disc degeneration (IDD). The gene expression profile of GSE23130 was downloaded from the Gene Expression Omnibus (GEO) database. Extracellular protein-differentially expressed genes (EP-DEGs) were screened by protein annotation databases, and we used Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) to analyze the functions and pathways of EP-DEGs. STRING and Cytoscape were used to construct protein-protein interaction (PPI) networks and identify hub EP-DEGs. NetworkAnalyst was used to analyze transcription factors (TFs) and microRNAs (miRNAs) that regulate hub EP-DEGs. A search of the Drug Signatures Database (DSigDB) for hub EP-DEGs revealed multiple drug molecules and drug-target interactions.Aims
Methods
In this investigation, we administered oxidative stress to nucleus pulposus cells (NPCs), recognized DNA-damage-inducible transcript 4 (DDIT4) as a component in intervertebral disc degeneration (IVDD), and devised a hydrogel capable of conveying small interfering RNA (siRNA) to IVDD. An in vitro model for oxidative stress-induced injury in NPCs was developed to elucidate the mechanisms underlying the upregulation of DDIT4 expression, activation of the reactive oxygen species (ROS)-thioredoxin-interacting protein (TXNIP)-NLRP3 signalling pathway, and nucleus pulposus pyroptosis. Furthermore, the mechanism of action of small interfering DDIT4 (siDDIT4) on NPCs in vitro was validated. A triplex hydrogel named siDDIT4@G5-P-HA was created by adsorbing siDDIT4 onto fifth-generation polyamidoamine (PAMAM) dendrimer using van der Waals interactions, and then coating it with hyaluronic acid (HA). In addition, we established a rat puncture IVDD model to decipher the hydrogel’s mechanism in IVDD.Aims
Methods
The aim of this study was to compare the clinical and radiological outcomes of patients with early-onset scoliosis (EOS), who had undergone spinal fusion after distraction-based spinal growth modulation using either traditional growing rods (TGRs) or magnetically controlled growing rods (MCGRs). We undertook a retrospective review of skeletally mature patients who had undergone fusion for an EOS, which had been previously treated using either TGRs or MCGRs. Measured outcomes included sequential coronal T1 to S1 height and major curve (Cobb) angle on plain radiographs and any complications requiring unplanned surgery before final fusion.Aims
Methods
Anchorage of pedicle screw rod instrumentation in the elderly spine with poor bone quality remains challenging. Our study aims to evaluate how the screw bone anchorage is affected by screw design, bone quality, loading conditions, and cementing techniques. Micro-finite element (µFE) models were created from micro-CT (μCT) scans of vertebrae implanted with two types of pedicle screws (L: Ennovate and R: S4). Simulations were conducted for a 10 mm radius region of interest (ROI) around each screw and for a full vertebra (FV) where different cementing scenarios were simulated around the screw tips. Stiffness was calculated in pull-out and anterior bending loads.Aims
Methods
To report the mid-term results of a modified self-growing rod (SGR) technique for the treatment of idiopathic and neuromuscular early-onset scoliosis (EOS). We carried out a retrospective analysis of 16 consecutive patients with EOS treated with an SGR construct at a single hospital between September 2008 and December 2014. General demographics and deformity variables (i.e. major Cobb angle, T1 to T12 length, T1 to S1 length, pelvic obliquity, shoulder obliquity, and C7 plumb line) were recorded preoperatively, and postoperatively at yearly follow-up. Complications and revision procedures were also recorded. Only patients with a minimum follow-up of five years after surgery were included.Aims
Methods
The aim of this retrospective study was to compare the correction achieved using a convex pedicle screw technique and a low implant density achieved using periapical concave-sided screws and a high implant density. We hypothesized that there would be no difference in outcome between the two techniques. We retrospectively analyzed a series of 51 patients with a thoracic adolescent idiopathic scoliosis. There were 26 patients in the convex pedicle screw group who had screws implanted periapically (Group 2) and a control group of 25 patients with bilateral pedicle screws (Group 1). The patients’ charts were reviewed and pre- and postoperative radiographs evaluated. Postoperative patient-reported outcome measures (PROMs) were recorded.Aims
Methods
Magnetically controlled growing rods (MCGR) have been gaining popularity in the management of early-onset scoliosis (EOS) over the past decade. We present our experience with the first 44 MCGR consecutive cases treated at our institution. This is a retrospective review of consecutive cases of MCGR performed in our institution between 2012 and 2018. This cohort consisted of 44 children (25 females and 19 males), with a mean age of 7.9 years (3.7 to 13.6). There were 41 primary cases and three revisions from other rod systems. The majority (38 children) had dual rods. The group represents a mixed aetiology including idiopathic (20), neuromuscular (13), syndromic (9), and congenital (2). The mean follow-up was 4.1 years, with a minimum of two years. Nine children graduated to definitive fusion. We evaluated radiological parameters of deformity correction (Cobb angle), and spinal growth (T1-T12 and T1-S1 heights), as well as complications during the course of treatment.Aims
Methods
To investigate metallosis in patients with magnetically controlled growing rods (MCGRs) and characterize the metal particle profile of the tissues surrounding the rod. This was a prospective observational study of patients with early onset scoliosis (EOS) treated with MCGRs and undergoing rod exchange who were consecutively recruited between February 2019 and January 2020. Ten patients were recruited (mean age 12 years (SD 1.3); 2 M:8 F). The configurations of the MCGR were studied to reveal the distraction mechanisms, with crucial rod parts being the distractable piston rod and the magnetically driven rotor inside the barrel of the MCGR. Metal-on-metal contact in the form of ring-like wear marks on the piston was found on the distracted portion of the piston immediately outside the barrel opening (BO) through which the piston rod distracts. Biopsies of paraspinal muscles and control tissue samples were taken over and away from the wear marks, respectively. Spectral analyses of the rod alloy and biopsies were performed to reveal the metal constituents and concentrations. Histological analyses of the biopsies were performed with haematoxylin and eosin staining.Aims
Methods
Significant correction of an adolescent idiopathic scoliosis in the coronal plane through a posterior approach is associated with hypokyphosis. Factors such as the magnitude of the preoperative coronal curve, the use of hooks, number of levels fused, preoperative kyphosis, screw density, and rod type have all been implicated. Maintaining the normal thoracic kyphosis is important as hypokyphosis is associated with proximal junctional failure (PJF) and early onset degeneration of the spine. The aim of this study was to determine if coronal correction per se was the most relevant factor in generating hypokyphosis. A total of 95 patients (87% female) with a median age of 14 years were included in our study. Pre- and postoperative radiographs were measured and the operative data including upper instrumented vertebra (UIV), lower instrumented vertebra (LIV), metal density, and thoracic flexibility noted. Further analysis of the post-surgical coronal outcome (group 1 < 60% correction and group 2 ≥ 60%) were studied for their association with the postoperative kyphosis in the sagittal plane using univariate and multivariate logistic regression.Aims
Methods
With the identification of literature shortfalls on the techniques employed in intraoperative navigated (ION) spinal surgery, we outline a number of measures which have been synthesised into a coherent operative technique. These include positioning, dissection, management of the reference frame, the grip, the angle of attack, the drill, the template, the pedicle screw, the wire, and navigated intrathecal analgesia. Optimizing techniques to improve accuracy allow an overall reduction of the repetition of the surgical steps with its associated productivity benefits including time, cost, radiation, and safety. Cite this article:
It is uncertain whether instrumented spinal fixation in nonambulatory children with neuromuscular scoliosis should finish at L5 or be extended to the pelvis. Pelvic fixation has been shown to be associated with up to 30% complication rates, but is regarded by some as the standard for correction of deformity in these conditions. The incidence of failure when comparing the most caudal level of instrumentation, either L5 or the pelvis, using all-pedicle screw instrumentation has not previously been reported. In this retrospective study, we compared nonambulatory patients undergoing surgery at two centres: one that routinely instrumented to L5 and the other to the pelvis. In all, 91 nonambulatory patients with neuromuscular scoliosis were included. All underwent surgery using bilateral, segmental, pedicle screw instrumentation. A total of 40 patients underwent fusion to L5 and 51 had their fixation extended to the pelvis. The two groups were assessed for differences in terms of clinical and radiological findings, as well as complications.Aims
Methods
The aim of this study was to compare the outcomes of surgery
using growing rods in patients with severe A review of a multicentre EOS database identified 107 children
with severe EOS (major curve ≥ 90°) treated with growing rods before
the age of ten years with a minimum follow-up of two years and three
or more lengthening procedures. From the same database, 107 matched
controls with moderate EOS were identified.Aims
Patients and Methods
The primary aim of this study was to evaluate the performance
and safety of magnetically controlled growth rods in the treatment
of early onset scoliosis. Secondary aims were to evaluate the clinical
outcome, the rate of further surgery, the rate of complications,
and the durability of correction. We undertook an observational prospective cohort study of children
with early onset scoliosis, who were recruited over a one-year period
and followed up for a minimum of two years. Magnetically controlled
rods were introduced in a standardized manner with distractions
performed three-monthly thereafter. Adverse events which were both related
and unrelated to the device were recorded. Ten children, for whom
relevant key data points (such as demographic information, growth
parameters, Cobb angles, and functional outcomes) were available,
were recruited and followed up over the period of the study. There
were five boys and five girls. Their mean age was 6.2 years (2.5
to 10).Aims
Patients and Methods
Magnetically controlled growing rods (MCGRs) allow non-invasive
correction of the spinal deformity in the treatment of early-onset
scoliosis. Conventional growing rod systems (CGRS) need repeated
surgical distractions: these are associated with the effect of the
‘law of diminishing returns’. The primary aim of this study was to quantify this effect in
MCGRs over sequential distractions. A total of 35 patients with a maximum follow-up of 57 months
were included in the study. There were 17 boys and 18 girls with
a mean age of 7.4 years (2 to 14). True Distraction (TD) was determined
by measuring the expansion gap on fluoroscopy. This was compared
with Intended Distraction (ID) and expressed as the ‘T/I’ ratio.
The T/I ratio and the Cobb angle were calculated at several time
points during follow-up.Aims
Patients and Methods
Magnetically controlled growing rod (MCGR) systems use non-invasive
spinal lengthening for the surgical treatment of early-onset scoliosis
(EOS). The primary aim of this study was to evaluate the performance
of these devices in the prevention of progression of the deformity.
A secondary aim was to record the rate of complications. An observational study of 31 consecutive children with EOS, of
whom 15 were male, who were treated between December 2011 and October
2017 was undertaken. Their mean age was 7.7 years (2 to 14). The
mean follow-up was 47 months (24 to 69). Distractions were completed
using the tailgating technique. The primary outcome measure was
correction of the radiographic deformity. Secondary outcomes were
growth, functional outcomes and complication rates.Aims
Patients and Methods
We present the results of correcting a double or triple curve
adolescent idiopathic scoliosis using a convex segmental pedicle
screw technique. We reviewed 191 patients with a mean age at surgery of 15 years
(11 to 23.3). Pedicle screws were placed at the convexity of each
curve. Concave screws were inserted at one or two cephalad levels
and two caudal levels. The mean operating time was 183 minutes (132
to 276) and the mean blood loss 0.22% of the total blood volume
(0.08% to 0.4%). Multimodal monitoring remained stable throughout
the operation. The mean hospital stay was 6.8 days (5 to 15).Aims
Patients and Methods
Many studies have investigated the kinematics of the lumbar spine and the morphological features of the lumbar discs. However, the segment-dependent immediate changes of the lumbar intervertebral space height during flexion-extension motion are still unclear. This study examined the changes of intervertebral space height during flexion-extension motion of lumbar specimens. First, we validated the accuracy and repeatability of a custom-made mechanical loading equipment set-up. Eight lumbar specimens underwent CT scanning in flexion, neural, and extension positions by using the equipment set-up. The changes in the disc height and distance between adjacent two pedicle screw entry points (DASEP) of the posterior approach at different lumbar levels (L3/4, L4/5 and L5/S1) were examined on three-dimensional lumbar models, which were reconstructed from the CT images.Objectives
Methods
We undertook a prospective non-randomised radiological study
to evaluate the preliminary results of using magnetically-controlled
growing rods (MAGEC System, Ellipse technology) to treat children
with early-onset scoliosis. Between January 2011 and January 2015, 19 children were treated
with magnetically-controlled growing rods (MCGRs) and underwent
distraction at three-monthly intervals. The mean age of our cohort
was 9.1 years (4 to 14) and the mean follow-up 22.4 months (5.1
to 35.2). Of the 19 children, eight underwent conversion from traditional growing
rods. Whole spine radiographs were carried out pre- and post-operatively:
image intensification was used during each lengthening in the outpatient
department. The measurements evaluated were Cobb angle, thoracic kyphosis,
proximal junctional kyphosis and spinal growth from T1 to S1.Aims
Patients and Methods
We reviewed 212 consecutive patients with adolescent
idiopathic scoliosis who underwent posterior spinal arthrodesis
using all pedicle screw instrumentation in terms of clinical, radiological
and Scoliosis Research Society (SRS)-22 outcomes. In Group 1 (51
patients), the correction was performed over two rods using bilateral
segmental pedicle screws. In Group 2 (161 patients), the correction
was performed over one rod using unilateral segmental pedicle screws
with the second rod providing stability of the construct
through two-level screw fixation at proximal and distal ends. The
mean age at surgery was
14.8 years in both groups. Comparison between groups showed no significant
differences with regard to age and Risser grade at surgery, pre-
and post-operative scoliosis angle, coronal Cobb correction, length
of hospital stay and SRS scores. Correction of upper thoracic curves
was significantly better in Group 1 (p = 0.02). Increased surgical time
and intra-operative blood loss was recorded in Group 1 (p <
0.001
and p = 0.04, respectively). The implant cost was reduced by mean
35% in Group 2 due to the lesser number of pedicle screws. Unilateral and bilateral pedicle screw techniques have both achieved
excellent deformity correction in adolescent patients with idiopathic
scoliosis, which was maintained at two-year follow-up. This has
been associated with high patient satisfaction and low complication
rates.
Conventional growing rods are the most commonly
used distraction-based devices in the treatment of progressive early-onset
scoliosis. This technique requires repeated lengthenings with the
patient anaesthetised in the operating theatre. We describe the
outcomes and complications of using a non-invasive magnetically
controlled growing rod (MCGR) in children with early-onset scoliosis.
Lengthening is performed on an outpatient basis using an external remote
control with the patient awake. Between November 2009 and March 2011, 34 children with a mean
age of eight years (5 to 12) underwent treatment. The mean length
of follow-up was 15 months (12 to 18). In total, 22 children were
treated with dual rod constructs and 12 with a single rod. The mean
number of distractions per patient was 4.8 (3 to 6). The mean pre-operative
Cobb angle was 69° (46° to 108°); this was corrected to a mean 47°
(28° to 91°) post-operatively. The mean Cobb angle at final review
was 41° (27° to 86°). The mean pre-operative distance from T1 to
S1 was 304 mm (243 to 380) and increased to 335 mm (253 to 400)
in the immediate post-operative period. At final review the mean distance
from T1 to S1 had increased to 348 mm (260 to 420). Two patients developed a superficial wound infection and a further
two patients in the single rod group developed a loss of distraction.
In the dual rod group, one patient had pull-out of a hook and one
developed prominent metalwork. Two patients had a rod breakage;
one patient in the single rod group and one patient in the dual
rod group. Our early results show that the MCGR is safe and effective
in the treatment of progressive early-onset scoliosis with the avoidance
of repeated surgical lengthenings. Cite this article:
We investigated the incidence of anomalies in
the vertebral arteries and Circle of Willis with three-dimensional
CT angiography in 55 consecutive patients who had undergone an instrumented
posterior fusion of the cervical spine. We recorded any peri-operative and post-operative complications.
The frequency of congenital anomalies was 30.9%, abnormal vertebral
artery blood flow was 58.2% and vertebral artery dominance 40%. The posterior communicating artery was occluded on one side in
41.8% of patients and bilaterally in 38.2%. Variations in the vertebral
arteries and Circle of Willis were not significantly related to
the presence or absence of posterior communicating arteries. Importantly,
18.2% of patients showed characteristic variations in the Circle
of Willis with unilateral vertebral artery stenosis or a dominant
vertebral artery, indicating that injury may cause lethal complications.
One patient had post-operative cerebellar symptoms due to intra-operative
injury of the vertebral artery, and one underwent a different surgical
procedure because of insufficient collateral circulation. Pre-operative assessment of the vertebral arteries and Circle
of Willis is essential if a posterior spinal fusion with instrumentation
is to be carried out safely. Cite this article:
Clinical, radiological, and Scoliosis Research
Society-22 questionnaire data were reviewed pre-operatively and
two years post-operatively for patients with thoracolumbar/lumbar
adolescent idiopathic scoliosis treated by posterior spinal fusion
using a unilateral convex segmental pedicle screw technique. A total
of 72 patients were included (67 female, 5 male; mean age at surgery
16.7 years (13 to 23)) and divided into groups: group 1 included
53 patients who underwent fusion between the vertebrae at the limit
of the curve (proximal and distal end vertebrae); group 2 included
19 patients who underwent extension of the fusion distally beyond
the caudal end vertebra. A mean scoliosis correction of 80% (45% to 100%) was achieved.
The mean post-operative lowest instrumented vertebra angle, apical
vertebra translation and trunk shift were less than in previous
studies. A total of five pre-operative radiological parameters differed
significantly between the groups and correlated with the extension
of the fusion distally: the size of the thoracolumbar/lumbar curve,
the lowest instrumented vertebra angle, apical vertebra translation,
the Cobb angle on lumbar convex bending and the size of the compensatory
thoracic curve. Regression analysis allowed an equation incorporating
these parameters to be developed which had a positive predictive
value of 81% in determining whether the lowest instrumented vertebra
should be at the caudal end vertebra or one or two levels more distal.
There were no differences in the Scoliosis Research Society-22 outcome
scores between the two groups (p = 0.17). In conclusion, thoracolumbar/lumbar curves in patients with adolescent
idiopathic scoliosis may be effectively treated by posterior spinal
fusion using a unilateral segmental pedicle screw technique. Five
radiological parameters correlate with the need for distal extension
of the fusion, and an equation incorporating these parameters reliably
informs selection of the lowest instrumented vertebra. Cite this article:
Transarticular screw fixation with autograft
is an established procedure for the surgical treatment of atlantoaxial instability.
Removal of the posterior arch of C1 may affect the rate of fusion.
This study assessed the rate of atlantoaxial fusion using transarticular
screws with or without removal of the posterior arch of C1. We reviewed
30 consecutive patients who underwent atlantoaxial fusion with a
minimum follow-up of two years. In 25 patients (group A) the posterior
arch of C1 was not excised (group A) and in five it was (group B).
Fusion was assessed on static and dynamic radiographs. In selected
patients CT imaging was also used to assess fusion and the position
of the screws. There were 15 men and 15 women with a mean age of
51.2 years (23 to 77) and a mean follow-up of 7.7 years (2 to 11.6).
Stable union with a solid fusion or a stable fibrous union was achieved
in 29 patients (97%). In Group A, 20 patients (80%) achieved a solid
fusion, four (16%) a stable fibrous union and one (4%) a nonunion.
In Group B, stable union was achieved in all patients, three having
a solid fusion and two a stable fibrous union. There was no statistically
significant difference between the status of fusion in the two groups.
Complications were noted in 12 patients (40%); these were mainly
related to the screws, and included malpositioning and breakage.
The presence of an intact or removed posterior arch of C1 did not
affect the rate of fusion in patients with atlantoaxial instability
undergoing C1/C2 fusion using transarticular screws and autograft. Cite this article:
We compared the clinical, radiological and quality-of-life
outcomes between hybrid and total pedicle screw instrumentation
in patients undergoing surgery for neuromuscular scoliosis. Total pedicle screw instrumentation provided shorter operating
times, less blood loss and better correction of the major curve
compared with hybrid constructs in patients undergoing surgery for
neuromuscular scoliosis.
This prospective multicentre study was undertaken
to determine segmental movement, disc height and sagittal alignment
after total disc replacement (TDR) in the lumbosacral spine and
to assess the correlation of biomechanical properties to clinical
outcomes. A total of 173 patients with degenerative disc disease and low
back pain for more than one year were randomised to receive either
TDR or multidisciplinary rehabilitation (MDR). Segmental movement
in the sagittal plane and disc height were measured using distortion
compensated roentgen analysis (DCRA) comparing radiographs in active flexion
and extension. Correlation analysis between the range of movement
or disc height and patient-reported outcomes was performed in both
groups. After two years, no significant change in movement in the
sagittal plane was found in segments with TDR or between the two
treatment groups. It remained the same or increased slightly in
untreated segments in the TDR group and in this group there was
a significant increase in disc height in the operated segments.
There was no correlation between segmental movement or disc height
and patient-reported outcomes in either group. In this study, insertion of an intervertebral disc prosthesis
TDR did not increase movement in the sagittal plane and segmental
movement did not correlate with patient-reported outcomes. This
suggests that in the lumbar spine the movement preserving properties
of TDR are not major determinants of clinical outcomes. Cite this article:
Fracture of a pedicle is a rare complication of spinal instrumentation using pedicular screws, but it can lead to instability and pain and may necessitate extension of the fusion. Osteosynthesis of the fractured pedicle by cerclage-wire fixation and augmentation of the screw fixation by vertebroplasty or temporary elongation of the fixation, allows stabilisation without sacrifice of the adjacent healthy segment. We describe three patients who developed a fracture of the pedicle in the most caudal instrumented vertebra early after lumbar spinal fusion. During revision surgery the pedicles were reduced and secured by a soft cerclage wire bilaterally. Fusion was obtained at the site of the primary instrumentation and healing of the pedicles was achieved. Cerclage wiring of the fractured pedicle seems to be safe and avoids permanent extension of the fusion without the sacrifice of an otherwise healthy segment.
We investigated the pre-operative and one-year post-operative health-related quality of life (HRQoL) outcome by using a Euroqol (EQ-5D) questionnaire in 230 patients who underwent surgery for lumbar spinal stenosis. Data were obtained from the National Swedish Registry for operations on the lumbar spine between 2001 and 2002. We analysed the pre- and postoperative quality of life data, age, gender, smoking habits, pain and walking ability. The relative differences were compared to a Swedish EQ-5D population survey. The mean age of the patients was 66 years, and there were 123 females (53%). Before the operation 62 (27%) of the patients could walk more than 500 m. One year after the operation 150 (65%) were able to walk 500 m or more. The mean EQ-5D score improved from 0.36 to 0.64, and the HRQoL improved in 184 (80%) of the patients. However, they did not reach the level reported by a matched population sample (mean difference 0.18). Women had lower pre- and post-operative EQ-5D scores than men. Severe low back pain was a predictor for a poor outcome.
Between January 1990 and December 2000 we carried out 226 SB Charité III disc replacements for lumbar disc degeneration in 160 patients. They were reviewed at a mean follow-up of 79 months (31 to 161) to determine the clinical and radiological outcome. The clinical results were collected by an independent observer, who was not involved in patient selection, treatment or follow-up, using a combination of outcome measures, including the Oswestry Disability Index. Pain was recorded using a visual analogue score, and the most recent radiographs were reviewed. Survival of the device was analysed by the Kaplan-Meier method and showed a cumulative survival of 35% at 156 months when radiological failure was taken as the endpoint. The mean improvement in the Oswestry disability index scores after disc replacement was 14% (6% to 21%) and the mean improvement in the pain score was 1.6 (0.46 to 2.73), both falling below the clinically significant threshold. Removal of the implant was required in 12 patients, four because of implant failure. These poor results indicate that further use of this implant is not justified.