To analyse the effectiveness of debridement and implant retention
(DAIR) in patients with hip periprosthetic joint infection (PJI)
and the relationship to patient characteristics. The outcome was
evaluated in hips with confirmed PJI and a follow-up of not less
than two years. Patients in whom DAIR was performed were identified from our
hip arthroplasty register (between 2004 and 2013). Adherence to
criteria for DAIR was assessed according to a previously published
algorithm.Aims
Patients and Methods
Taper junctions between modular hip arthroplasty femoral heads and stems fail by wear or corrosion which can be caused by relative motion at their interface. Increasing the assembly force can reduce relative motion and corrosion but may also damage surrounding tissues. The purpose of this study was to determine the effects of increasing the impaction energy and the stiffness of the impactor tool on the stability of the taper junction and on the forces transmitted through the patient’s surrounding tissues. A commercially available impaction tool was modified to assemble components in the laboratory using impactor tips with varying stiffness at different applied energy levels. Springs were mounted below the modular components to represent the patient. The pull-off force of the head from the stem was measured to assess stability, and the displacement of the springs was measured to assess the force transmitted to the patient’s tissues.Objectives
Methods
The aims of this study were to evaluate the clinical and radiological
outcomes of instrumented posterolateral fusion (PLF) performed in
patients with rheumatoid arthritis (RA). A total of 40 patients with RA and 134 patients without RA underwent
instrumented PLF for spinal stenosis between January 2003 and December
2011. The two groups were matched for age, gender, bone mineral
density, the history of smoking and diabetes, and number of fusion
segments. The clinical outcomes measures included the visual analogue scale
(VAS) and the Korean Oswestry Disability Index (KODI), scored before
surgery, one year and two years after surgery. Radiological outcomes
were evaluated for problems of fixation, nonunion, and adjacent
segment disease (ASD). The mean follow-up was 36.4 months in the RA
group and 39.1 months in the non-RA group.Aims
Methods
We describe 13 patients with cerebral palsy and
lordoscoliosis/hyperlordosis of the lumbar spine who underwent a posterior
spinal fusion at a mean age of 14.5 years (10.8 to 17.4) to improve
sitting posture and relieve pain. The mean follow-up was 3.3 years
(2.2 to 6.2). The mean pre-operative lumbar lordosis was 108° (80
to 150°) and was corrected to 62° (43° to
85°); the mean thoracic kyphosis from 17° (-23° to
35°) to 47° (25° to 65°);
the mean scoliosis from 82° (0° to 125°)
to 22° (0° to 40°); the mean pelvic
obliquity from 21° (0° to 38°)
to 3° (0° to 15°); the mean sacral
slope from 79° (54° to 90°) to
50° (31° to 66°). The mean pre-operative
coronal imbalance was 5 cm (0 cm to 8.9 cm) and was corrected to
0.6 cm (0 to 3.2). The mean sagittal imbalance of -8 cm (-16 cm
to 7.8 cm) was corrected to -1.6 cm
(-4 cm to 2.5 cm). The mean operating time was 250 minutes (180
to 360 minutes) and intra-operative blood loss 0.8 of estimated
blood volume (0.3 to 2 estimated blood volume). The mean intensive
care and hospital stay were 3.5 days (2 to 8) and 14.5 days (10
to 27), respectively. Three patients lost a significant amount of
blood intra-operatively and subsequently developed chest or urinary
infections and superior mesenteric artery syndrome. An increased pre-operative lumbar lordosis and sacral slope were
associated with increased peri-operative morbidity: scoliosis and
pelvic obliquity were not. A reduced lumbar lordosis and increased
thoracic kyphosis correlated with better global sagittal balance
at follow-up. All patients and their parents reported excellent
surgical outcomes. Lordoscoliosis and hyperlordosis are associated with significant
morbidity in quadriplegic patients. They are rare deformities and
their treatment is challenging. Sagittal imbalance is the major
component: it can be corrected by posterior fusion of the spine
with excellent functional results. Cite this article:
The bony shoulder stability ratio (BSSR) allows for quantification of the bony stabilisers Four polyethylene balls (radii: 19.1 mm to 38.1 mm) were used to mould four fitting sockets in four different depths (3.2 mm to 19.1mm). The SR was measured in biomechanical congruent and incongruent experimental series. The experimental SR of a congruent system was compared with the calculated SR based on the BSSR approach. Differences in SR between congruent and incongruent experimental conditions were quantified. Finally, the experimental SR was compared with either calculated SR based on the socket concavity or plastic ball radius.Objectives
Methods
The aim of this study was to evaluate the effects of using a
portable, accelerometer-based surgical navigation system (KneeAlign2)
in total knee arthroplasty (TKA) on the alignment of the femoral
component, and blood loss. A total of 241 consecutive patients with primary osteoarthritis
of the knee were enrolled in this prospective, randomised controlled
study. There were 207 women and 34 men. The mean age of the patients
was 74.0 years (57 to 89). The KneeAlign2 system was used for distal
femoral resection in 121 patients (KA2 group) and a conventional intramedullary
femoral guide was used in 120 patients (IM group).Aims
Patients and Methods
The aims of this study were to determine the proportion of patients
with outlier varus or valgus alignment in kinematically aligned
total knee arthroplasty (TKA), whether those with outlier varus
or valgus alignment have higher forces in the medial or lateral
compartments of the knee than those with in-range alignment and
whether measurements of the alignment of the limb, knee and components
predict compartment forces. The intra-operative forces in the medial and lateral compartments
were measured with an instrumented tibial insert in 67 patients
who underwent a kinematically aligned TKA during passive movement.
The mean of the forces at full extension, 45° and 90° of flexion
determined the force in the medial and lateral compartments. Measurements
of the alignment of the limb and the components included the hip-knee-ankle
(HKA) angle, proximal medial tibial angle (PMTA), and distal lateral
femoral angle (DLFA). Measurements of the alignment of the knee
and the components included the tibiofemoral angle (TFA), tibial
component angle (TCA) and femoral component angle (FCA). Alignment was
measured on post-operative, non-weight-bearing anteroposterior (AP)
scanograms and categorised as varus or valgus outlier or in-range
in relation to mechanically aligned criteria.Aims
Patients and Methods
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:
Chronic osteomyelitis may recur if dead space management, after
excision of infected bone, is inadequate. This study describes the
results of a strategy for the management of deep bone infection
and evaluates a new antibiotic-loaded biocomposite in the eradication
of infection from bone defects. We report a prospective study of 100 patients with chronic osteomyelitis,
in 105 bones. Osteomyelitis followed injury or surgery in 81 patients.
Nine had concomitant septic arthritis. 80 patients had comorbidities
(Cierny-Mader (C-M) Class B hosts). Ten had infected nonunions. All patients were treated by a multidisciplinary team with a
single-stage protocol including debridement, multiple sampling,
culture-specific systemic antibiotics, stabilisation, dead space
filling with the biocomposite and primary skin closure. Aims
Patients and Methods
In this study of patients who underwent internal fixation without
fusion for a burst thoracolumbar or lumbar fracture, we compared
the serial changes in the injured disc height (DH), and the fractured
vertebral body height (VBH) and kyphotic angle between patients
in whom the implants were removed and those in whom they were not. Radiological
parameters such as injured DH, fractured VBH and kyphotic angle
were measured. Functional outcomes were evaluated using the Greenough
low back outcome scale and a VAS scale for pain. Between June 1996 and May 2012, 69 patients were analysed retrospectively;
47 were included in the implant removal group and 22 in the implant
retention group. After a mean follow-up of 66 months (48 to 107),
eight patients (36.3%) in the implant retention group had screw
breakage. There was no screw breakage in the implant removal group.
All radiological and functional outcomes were similar between these
two groups. Although solid union of the fractured vertebrae was
achieved, the kyphotic angle and the anterior third of the injured
DH changed significantly with time (p <
0.05). Methods
Results
The aim of this study is to introduce and investigate the efficacy
and feasibility of a new vertebral osteotomy technique, vertebral
column decancellation (VCD), for rigid thoracolumbar kyphotic deformity
(TLKD) secondary to ankylosing spondylitis (AS). We took 39 patients from between January 2009 and January 2013
(26 male, 13 female, mean age 37.4 years, 28 to 54) with AS and
a TLKD who underwent VCD (VCD group) and compared their outcome
with 45 patients (31 male, 14 female, mean age 34.8 years, 23 to
47) with AS and TLKD, who underwent pedicle subtraction osteotomy
(PSO group), according to the same selection criteria. The technique
of VCD was performed at single vertebral level in the thoracolumbar
region of AS patients according to classification of AS kyphotic
deformity. Pre- and post-operative chin-brow vertical angle (CBVA),
sagittal vertical axis (SVA) and sagittal Cobb angle in the thoracolumbar
region were reviewed in the VCD and PSO groups. Intra- , post-operative
and general complications were analysed in both group.Aims
Patients and Methods
The aim of this study was a quantitative analysis of a surgeon’s
learning curve for scoliosis surgery and the relationship between
the surgeon’s experience and post-operative outcomes, which has
not been previously well described. We have investigated the operating time as a function of the
number of patients to determine a specific pattern; we analysed
factors affecting the operating time and compared intra- and post-operative
outcomes. We analysed 47 consecutive patients undergoing scoliosis
surgery performed by a single, non-trained scoliosis surgeon. Operating time
was recorded for each of the four parts of the procedures: dissection,
placement of pedicle screws, reduction of the deformity and wound
closure.Aims
Patients and Methods
The purpose of this study was to measure the
radiological parameters of femoral component alignment of the Oxford
Phase 3 unicompartmental knee replacement (UKR), and evaluate their
effect on clinical outcome. Multiple regression analysis was used
to examine the relative contributions of the radiological assessment
of femoral component alignment in 189 consecutive UKRs performed
by a single surgeon. The American Knee Society scores were compared
between groups, defined as being within or outside recommended tolerances
of the position of the femoral component. For the flexion/extension
position 21 UKRs (11.1%) lay outside the recommended limits, and for
posterior overhang of the femoral component nine (4.8%) lay outside
the range. The pre-operative hip/knee/ankle (HKA) angle, narrowest
canal distance from the distal femoral entry point of the alignment
jig and coronal entry-point position had significant effects on
the flexion/extension position. Pre-operative HKA angle had a significant
influence on posterior overhang of the femoral component. However,
there was no significant difference in American Knee Society scores
relative to the position of the femoral component.
We report our early experience with the use of
a new prosthesis, the Modular Hemipelvic Prosthesis II, for reconstruction
of the hemipelvis after resection of a primary malignant peri-acetabular
tumour involving the sacroiliac joint. We retrospectively reviewed the outcome of 17 patients who had
undergone resection of a pelvic tumour and reconstruction with this
prosthesis between July 2002 and July 2010. One patient had a type I+II+III+IV resection (ilium + peri-acetabulum
+ pubis/ischium + sacrum) and 16 had a type I+II+IV resection (ilium
+ acetabulum + sacrum). The outcome was assessed at a mean follow-up
of 33 months (15 to 59). One patient was alive with disease, 11
were alive without disease and five had died of disease. The overall
five-year survival rate was 62.4%. Six patients had a local recurrence.
The mean Musculoskeletal Tumour Society score was 58% (33 to 77).
Deep infection occurred in two patients, problems with wound healing
in five and dislocation in one. For patients with a primary malignant peri-acetabular sarcoma
involving the sacroiliac joint, we believe that this new prosthesis
is a viable option for reconstruction of the bony defect left following
resection of the tumour. It results in a satisfactory functional
outcome with an acceptable rate of complications. Cite this article:
Infection of implants is a major problem in elective and trauma surgery. Heating is an effective way to reduce the bacterial load in food preparation, and studies on hyperthermia treatment for cancer have shown that it is possible to heat metal objects with pulsed electromagnetic fields selectively (PEMF), also known as induction heating. We therefore set out to answer the following research question: is non-contact induction heating of metallic implants effective in reducing bacterial load Titanium alloy cylinders (Ti6Al4V) were exposed to PEMF from an induction heater with maximum 2000 watts at 27 kHz after being contaminated with five different types of micro-organisms: Objectives
Methods
Implant-related infection is one of the most devastating complications in orthopaedic surgery. Many surface and/or material modifications have been developed in order to minimise this problem; however, most of the We describe a method for the study of bacterial adherence in the presence of preosteoblastic cells. For this purpose we mixed different concentrations of bacterial cells from collection and clinical strains of staphylococci isolated from implant-related infections with preosteoblastic cells, and analysed the minimal concentration of bacteria able to colonise the surface of the material with image analysis.Objectives
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