Matrix-induced autologous chondrocyte implantation
(MACI) is an established technique used to treat osteochondral lesions
in the knee. For larger osteochondral lesions (>
5 cm2)
deeper than approximately 8 mm we have combined the use of two MACI
membranes with impaction grafting of the subchondral bone. We report
our results of 14 patients who underwent the ‘bilayer collagen membrane’
technique (BCMT) with a mean follow-up of 5.2 years (2 to 8). There
were 12 men and two women with a mean age of 23.6 years (16 to 40).
The mean size of the defect was 7.2 cm2 (5.2 to 12 cm2)
and were located on the medial (ten) or lateral (four) femoral condyles.
The mean modified Cincinnati knee score improved from 45.1 (22 to
70) pre-operatively to 82.8 (34 to 98) at the most recent review
(p <
0.05). The visual analogue pain score improved from 7.3
(4 to 10) to 1.7 (0 to 6) (p <
0.05). Twelve patients were considered
to have a good or excellent clinical outcome. One graft failed at
six years. The BCMT resulted in excellent functional results and durable
repair of large and deep osteochondral lesions without a high incidence
of graft-related complications.
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:
We report the clinical and radiological results of a two- to three-year prospective randomised study which was designed to compare a minimally-invasive technique with a standard technique in total knee replacement and was undertaken between January 2004 and May 2007. The mini-midvastus approach was used on 50 patients (group A) and a standard approach on 50 patients (group B). The mean follow-up in both groups was 23 months (24 to 35). The functional outcome was better in group A up to nine months after operation, as shown by statistically significant differences in the mean function score, mean total score and the mean Oxford knee score (all, p = 0.05). Patients in group A had statistically significant greater early flexion (p = 0.04) and reached their greatest mean knee flexion of 126.5° (95° to 135°) 21 days after operation. However, at final follow-up there was no significant difference in the mean maximum flexion between the groups (p = 0.08). Technical errors were identified in six patients from group A (12%) on radiological evaluation. Based on these results, the authors currently use minimally-invasive techniques in total knee replacement in selected cases only.
Interfacial defects between the cement mantle and a hip implant may arise from constrained shrinkage of the cement or from air introduced during insertion of the stem. Shrinkage-induced interfacial porosity consists of small pores randomly located around the stem, whereas introduced interfacial gaps are large, individual and less uniformly distributed areas of stem-cement separation. Using a validated CT-based technique, we investigated the extent, morphology and distribution of interfacial gaps for two types of stem, the Charnley-Kerboul and the Lubinus SPII, and for two techniques of implantation, line-to-line and undersized. The interfacial gaps were variable and involved a mean of 6.43% (
Recent studies have shown that modulating inflammation-related
lipid signalling after a bone fracture can accelerate healing in
animal models. Specifically, decreasing 5-lipoxygenase (5-LO) activity
during fracture healing increases cyclooxygenase-2 (COX-2) expression
in the fracture callus, accelerates chondrogenesis and decreases
healing time. In this study, we test the hypothesis that 5-LO inhibition
will increase direct osteogenesis. Bilateral, unicortical femoral defects were used in rats to measure
the effects of local 5-LO inhibition on direct osteogenesis. The
defect sites were filled with a polycaprolactone (PCL) scaffold
containing 5-LO inhibitor (A-79175) at three dose levels, scaffold
with drug carrier, or scaffold only. Drug release was assessed Objectives
Methods
Despite many claims of good wear properties following
total knee replacement (TKR) with an oxidised zirconium (OxZr) femoral
component, there are conflicting clinical results. We hypothesised
that there would be no difference in either the mid-term clinical
and radiological outcomes or the characteristics of the polyethylene
wear particles (weight, size and shape) in patients using an OxZr
or cobalt-chrome (CoCr) femoral component. In all 331 patients underwent
bilateral TKR, receiving an OxZr femoral component in one knee and
a CoCr femoral component in the other. The mean follow-up was 7.5
years (6 to 8). Following aspiration, polyethylene wear particles
were analysed using thermogravimetric methods and scanning electron
microscopy. At the most recent follow-up, the mean Knee Society
score, Western Ontario and McMaster Universities Osteoarthritis
Index score, range of movement and satisfaction score were not significantly
different in the two groups. The mean weight, size, aspect ratio
and roundness of the aspirated wear particles were similar for each
femoral component. Survivorship of the femoral, tibial and patellar
components was 100% in both groups. In the absence of evidence of an advantage in the medium term
we cannot justify the additional expense of an OxZr femoral component.
The treatment of substantial proximal femoral
bone loss in young patients with developmental dysplasia of the
hip (DDH) is challenging. We retrospectively analysed the outcome
of 28 patients (30 hips) with DDH who underwent revision total hip
replacement (THR) in the presence of a deficient proximal femur,
which was reconstructed with an allograft prosthetic composite.
The mean follow-up was 15 years (8.5 to 25.5). The mean number of
previous THRs was three (1 to 8). The mean age at primary THR and
at the index reconstruction was 41 years (18 to 61) and 58.1 years
(32 to 72), respectively. The indication for revision included mechanical
loosening in 24 hips, infection in three and peri-prosthetic fracture
in three. Six patients required removal and replacement of the allograft
prosthetic composite, five for mechanical loosening and one for
infection. The survivorship at ten, 15 and 20 years was 93% (95%
confidence interval (CI) 91 to 100), 75.5% (95% CI 60 to 95) and
75.5% (95% CI 60 to 95), respectively, with 25, eight, and four
patients at risk, respectively. Additionally, two junctional nonunions
between the allograft and host femur required bone grafting and
plating. An allograft prosthetic composite affords a good long-term outcome
in the management of proximal femoral bone loss in revision THR
in patients with DDH, while preserving distal host bone.
Surgical marking during tendon surgery is often used for technical
and teaching purposes. This study investigates the effect of a gentian
violet ink marker pen, a common surgical marker, on the viability
of the tissue and cells of tendon.
Objectives
Methods
The stress response to trauma is the summation of the physiological response to the injury (the ‘first hit’) and by the response to any on-going physiological disturbance or subsequent trauma surgery (the ‘second hit’). Our animal model was developed in order to allow the study of each of these components of the stress response to major trauma. High-energy, comminuted fracture of the long bones and severe soft-tissue injuries in this model resulted in a significant tropotropic (depressor) cardiovascular response, transcardiac embolism of medullary contents and activation of the coagulation system. Subsequent stabilisation of the fractures using intramedullary nails did not significantly exacerbate any of these responses.
In 20 patients undergoing hybrid total hip arthroplasty, the reproducibility and accuracy of templating using digital radiographs were assessed. Digital images were manipulated using either a ten-pence coin as a marker to scale for magnification, or two digital-line methods using computer software. On-screen images were templated with standard acetate templates and compared with templating performed on hard-copy digital prints. The digital-line methods were the least reliable and accuracy of sizing compared with the inserted prostheses varied between −1.6% and +10.2%. The hard-copy radiographs showed better reproducibility than the ten-pence coin method, but were less accurate with 3.7% undersizing. The ten-pence coin method was the most accurate, with no significant differences for offset or acetabulum, and undersizing of only 0.9%. On-screen templating of digital radiographs with standard acetate templates is accurate and reproducible if a radiopaque marker such as a ten-pence coin is included when the original radiograph is taken.
In posterior stabilised total knee replacement
(TKR) a larger femoral component is sometimes selected to manage the
increased flexion gap caused by resection of the posterior cruciate
ligament. However, concerns remain regarding the adverse effect
of the increased anteroposterior dimensions of the femoral component
on the patellofemoral (PF) joint. Meanwhile, the gender-specific
femoral component has a narrower and thinner anterior flange and
is expected to reduce the PF contact force. PF contact forces were
measured at 90°, 120°, 130° and 140° of flexion using the NexGen
Legacy Posterior Stabilized (LPS)-Flex Fixed Bearing Knee system
using Standard, Upsized and Gender femoral components during TKR.
Increasing the size of the femoral component significantly increased
mean PF forces at 120°, 130° and 140° of flexion (p = 0.005, p <
0.001 and p <
0.001, respectively). No difference was found in
contact force between the Gender and the Standard components. Among
the patients who had overhang of the Standard component, mean contact
forces with the Gender component were slightly lower than those
of the Standard component, but no statistical difference was found
at 90°, 120°, 130° or 140° of flexion (p = 0.689, 0.615, 0.253 and
0.248, respectively). Upsized femoral components would increase PF forces in deep knee
flexion. Gender-specific implants would not reduce PF forces.
We investigated the clinical response to arthroscopic
synovectomy in patients with undifferentiated chronic monoarthritis
(UCMA) of the wrist. Arthroscopic synovectomy was performed on 20
wrists in 20 patients with UCMA of the wrist who had not responded
to non-steroidal anti-inflammatory drugs. The mean duration of symptoms
at the time of surgery was 4.3 months (3 to 7) and the mean follow-up
was 51.8 months (24 to 94). Inflamed synovium was completely removed
from the radiocarpal, midcarpal and distal radioulnar joints using
more portals than normal. After surgery, nine patients had early
remission of synovitis and 11 with uncontrolled synovitis received
antirheumatic medication. Overall, there was significant improvement
in terms of pain relief, range of movement and Mayo score. Radiological
deterioration was seen in five patients who were diagnosed as having rheumatoid
arthritis during the follow-up period. Lymphoid follicles and severe
lymphocyte infiltration were seen more often in synovial biopsies
from patients with uncontrolled synovitis. These results suggest that arthroscopic synovectomy provides
pain relief and functional improvement, and allows rapid resolution
of synovitis in about half of patients with UCMA of the wrist.
We performed a three-year radiostereometric analysis (RSA) study of the Elite Plus femoral component on 25 patients undergoing primary total hip replacement. Additional assessments and measurements from standard radiographs were also made. Subsidence of the stem occurred at the cement-stem interface. At 36 months the subsidence of the stem centroid was a mean of 0.30 mm (0.02 to 1.28), and was continuing at a slow rate. At the same time point, internal rotation and posterior migration of the femoral head had ceased. One stem migrated excessively and additional assessments suggested that this was probably due to high patient demand. The failure rate of 4% in our study is consistent with data from arthroplasty registers but contrasts with poor results from another RSA study, and from some clinical studies. We believe that the surgical technique, particularly the use of high-viscosity cement, may have been an important factor contributing to our results.
Controversy surrounds the most appropriate treatment
method for patients with a rupture of the tendo Achillis. The aim
of this study was to assess the long term rate of re-rupture following
management with a non-operative functional protocol. We report the outcome of 945 consecutive patients (949 tendons)
diagnosed with a rupture of the tendo Achillis managed between 1996
and 2008. There were 255 female and 690 male patients with a mean
age of 48.97 years (12 to 86). Delayed presentation was defined
as establishing the diagnosis and commencing treatment more than
two weeks after injury. The overall rate of re-rupture was 2.8%
(27 re-ruptures), with a rate of 2.9%
(25 re-ruptures) for those with an acute presentation and 2.7% (two
re-ruptures) for those with delayed presentation. This study of non-operative functional management of rupture
of the tendo Achillis is the largest of its kind in the literature. Our
rates of re-rupture are similar to, or better than, those published
for operative treatment. We recommend our regime for patients of
all ages and sporting demands, but it is essential that they adhere
to the protocol.
We report the long-term results of revision total
hip replacement using femoral impaction allografting with both uncemented
and cemented Freeman femoral components. A standard design of component
was used in both groups, with additional proximal hydroxyapatite
coating in the uncemented group. A total of 33 hips in 30 patients received
an uncemented component and 31 hips in 30 patients a cemented component.
The mean follow-up was 9.8 years (2 to 17) in the uncemented group
and 6.2 years (1 to 11) in the cemented group. Revision procedures
(for all causes) were required in four patients (four hips) in the
uncemented group and in five patients (five hips) in the cemented
group. Harris hip scores improved significantly in both groups and
were maintained independently of the extent of any migration of
the femoral component within the graft or graft–cement mantle.
We describe the results of surgical treatment in a prospective study of 183 consecutive cases of subluxation (101) and dislocation (82) of the shoulder secondary to obstetric brachial plexus palsy between 1995 and 2000. Neurological recovery was rated ‘good’ or ‘useful’ in all children, whose lesions fell into groups 1, 2 or 3 of the Narakas classification. The mean age at operation was 47 months (3 to 204). The mean follow-up was 40 months (24 to 124). The mean gain in function was 3.6 levels (9.4 to 13) using the Mallet score and 2 (2.1 to 4.1) on the Gilbert score. The mean active global range of shoulder movement was increased by 73°; the mean range of active lateral rotation by 58° and that of supination of the forearm by 51°. Active medial rotation was decreased by a mean of 10°. There were 20 failures. The functional outcome is related to the severity of the neurological lesion, the duration of the dislocation and onset of deformity.
Biomechanical studies involving all-wire and hybrid types of circular frame have shown that oblique tibial fractures remain unstable when they are loaded. We have assessed a range of techniques for enhancing the fixation of these fractures. Eight models were constructed using Sawbones tibiae and standard Sheffield ring fixators, to which six additional fixation techniques were applied sequentially. The major component of displacement was shear along the obliquity of the fracture. This was the most sensitive to any change in the method of fixation. All additional fixation systems were found to reduce shear movement significantly, the most effective being push-pull wires and arched wires with a three-hole bend. Less effective systems included an additional half pin and arched wires with a shallower arc. Angled pins were more effective at reducing shear than transverse pins. The choice of additional fixation should be made after consideration of both the amount of stability required and the practicalities of applying the method to a particular fracture.
We have investigated the changes in anterior laxity of the knee in response to direct electrical stimulation of eight normal and 45 reconstructed anterior cruciate ligaments (ACLs). In the latter, the mean time from reconstruction was 26.7 months (24 to 32). The ACL was stimulated electrically using a bipolar electrode probe during arthroscopy. Anterior laxity was examined with the knee flexed at 20° under a force of 134 N applied anteriorly to the tibia using the KT-2000 knee arthrometer before, during and after electrical stimulation. Anterior tibial translation in eight normal and 17 ACL-reconstructed knees was significantly decreased during stimulation, compared with that before stimulation. In 28 knees with reconstruction of the ACL, in 22 of which the grafts were found to have detectable somatosensory evoked potentials during stimulation, anterior tibial translation was not decreased. These findings suggest that the ACL-hamstring reflex arc in normal knees may contribute to the functional stability and that this may not be fully restored after some reconstructions of the ACL.
The main object of this study was to use a geometric morphometric
approach to quantify the left-right symmetry of talus bones. Analysis was carried out using CT scan images of 11 pairs of
intact tali. Two important geometric parameters, volume and surface
area, were quantified for left and right talus bones. The geometric
shape variations between the right and left talus bones were also
measured using deviation analysis. Furthermore, location of asymmetry
in the geometric shapes were identified. Numerical results showed that talus bones are bilaterally symmetrical
in nature, and the difference between the surface area of the left
and right talus bones was less than 7.5%. Similarly, the difference
in the volume of both bones was less than 7.5%. Results of the three-dimensional
(3D) deviation analyses demonstrated the mean deviation between
left and right talus bones were in the range of -0.74 mm to 0.62
mm. It was observed that in eight of 11 subjects, the deviation
in symmetry occurred in regions that are clinically less important
during talus surgery. Objective
Methods
Results
Inherent disadvantages of reverse shoulder arthroplasty
designs based on the Grammont concept have raised a renewed interest
in less-medialised designs and techniques. The aim of this study
was to evaluate the outcome of reverse shoulder arthroplasty (RSA)
with the fully-constrained, less-medialised, Bayley–Walker prosthesis performed
for the treatment of rotator-cuff-deficient shoulders with glenohumeral
arthritis. A total of 97 arthroplasties in 92 patients (53 women
and 44 men, mean age 67 years (standard deviation ( The Bayley–Walker prosthesis provides reliable pain relief and
reasonable functional improvement for patients with symptomatic
cuff-deficient shoulders. Compared with other designs of RSA, it
offers a modest improvement in forward elevation, but restores external
rotation to some extent and prevents scapular notching. A longer
follow-up is required to assess the survival of the prosthesis and
the clinical performance over time. Cite this article: