Accurate placement of the acetabular component during total hip
arthroplasty (THA) is an important factor in the success of the
procedure. However, the reported accuracy varies greatly and is
dependent upon whether free hand or navigated techniques are used.
The aim of this study was to assess the accuracy of an instrument
system that incorporates 3D printed, patient-specific guides designed
to optimise the placement of the acetabular component. A total of 100 consecutive patients were prospectively enrolled
and the accuracy of placement of the acetabular component was measured
using post-operative CT scans.Aims
Patients and Methods
We report the kinematic and early clinical results
of a patient- and observer-blinded randomised controlled trial in which
CT scans were used to compare potential impingement-free range of
movement (ROM) and acetabular component cover between patients treated
with either the navigated ‘femur-first’ total hip arthroplasty (THA) method
(n = 66; male/female 29/37, mean age 62.5 years; 50 to 74) or conventional
THA (n = 69; male/female 35/34, mean age 62.9 years; 50 to 75).
The Hip Osteoarthritis Outcome Score, the Harris hip score, the
Euro-Qol-5D and the Mancuso THA patient expectations score were
assessed at six weeks, six months and one year after surgery. A
total of 48 of the patients (84%) in the navigated ‘femur-first’
group and 43 (65%) in the conventional group reached all the desirable
potential ROM boundaries without prosthetic impingement for activities
of daily living (ADL) in flexion, extension, abduction, adduction
and rotation (p = 0.016). Acetabular component cover and surface
contact with the host bone were >
87% in both groups. There was
a significant difference between the navigated and the conventional
groups’ Harris hip scores six weeks after surgery (p = 0.010). There
were no significant differences with respect to any clinical outcome
at six months and one year of follow-up. The navigated ‘femur-first’
technique improves the potential ROM for ADL without prosthetic
impingement, although there was no observed clinical difference
between the two treatment groups. Cite this article:
Studies reporting specifically on squeaking in total hip arthroplasty have focused on cementless, and not on hybrid, fixation. We hypothesised that the cement mantle of the femur might have a damping effect on the sound transmitted through the metal stem. The objective of this study was to test the effect of cement on sound propagation along different stem designs and under different fixation conditions. An Objectives
Methods
Periprosthetic femoral fractures (PFF) following total hip arthroplasty
(THA) are devastating complications that are associated with functional
limitations and increased overall mortality. Although cementless
implants have been associated with an increased risk of PFF, the
precise contribution of implant geometry and design on the risk
of both intra-operative and post-operative PFF remains poorly investigated.
A systematic review was performed to aggregate all of the PFF literature
with specific attention to the femoral implant used. A systematic search strategy of several journal databases and
recent proceedings from the American Academy of Orthopaedic Surgeons
was performed. Clinical articles were included for analysis if sufficient
implant description was provided. All articles were reviewed by
two reviewers. A review of fundamental investigations of implant
load-to-failure was performed, with the intent of identifying similar
conclusions from the clinical and fundamental literature.Aims
Patients and Methods
The influence of identifiable pre-operative factors on the outcome
of eccentric rotational acetabular osteotomy (ERAO) is unknown.
We aimed to determine the factors that might influence the outcome,
in order to develop a scoring system for predicting the prognosis
for patients undergoing this procedure. We reviewed 700 consecutive ERAOs in 54 men and 646 women with
symptomatic acetabular dysplasia or early onset osteoarthritis (OA)
of the hip, which were undertaken between September 1989 and March
2013. The patients’ pre-operative background, clinical and radiological
findings were examined retrospectively. Multivariate Cox regression
analysis was performed using the time from the day of surgery to
a conversion to total hip arthroplasty (THA) as an endpoint. A risk
score was calculated to predict the prognosis for conversion to
THA, and its predictive capacity was investigated.Aims
Patients and Methods
One method of femoral head preservation following avascular necrosis
(AVN) is core decompression and insertion of a tantalum rod. However,
there may be a high failure rate associated with this procedure.
The purpose of this study was to document the clinical and radiological
outcomes following total hip arthroplasty (THA) subsequent to failed
tantalum rod insertion. A total of 37 failed tantalum rods requiring total hip arthroplasty
were identified from a prospective database. There were 21 hips
in 21 patients (12 men and nine women, mean age 37 years, 18 to
53) meeting minimum two year clinical and radiographic follow-up
whose THAs were carried out between November 2002 and April 2013
(mean time between tantalum rod implantation and conversion to a
THA was 26 months, 6 to 72). These were matched by age and gender
to individuals (12 men, nine women, mean age 40 years, 18 to 58)
receiving THA for AVN without prior tantalum rod insertion.Aims
Patients and Methods
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 degree of displacement of a fracture of the distal radius
is an important factor which can be assessed using simple radiographic
measurements. Our aim was to investigate the reliability and reproducibility
of these measurements and to determine if they should be used clinically. A 10% sample was randomly generated from 3670 consecutive adult
patients who had presented to University Hospitals of Leicester
NHS Trust between 2007 and 2010 with a fracture of the distal radius.
Radiographs of the 367 patients were assessed by two independent
reviewers. Four measurements of displacement of the fracture were recorded
and the inter-observer correlation assessed using the intra-class
correlation coefficient.Aims
Patients and Methods
The effective capture of outcome measures in
the healthcare setting can be traced back to Florence Nightingale’s
investigation of the in-patient mortality of soldiers wounded in
the Crimean war in the 1850s. Only relatively recently has the formalised collection of outcomes
data into Registries been recognised as valuable in itself. With the advent of surgeon league tables and a move towards value
based health care, individuals are being driven to collect, store
and interpret data. Following the success of the National Joint Registry, the British
Association of Spine Surgeons instituted the British Spine Registry.
Since its launch in 2012, over 650 users representing the whole
surgical team have registered and during this time, more than 27 000
patients have been entered onto the database. There has been significant publicity regarding the collection
of outcome measures after surgery, including patient-reported scores.
Over 12 000 forms have been directly entered by patients themselves,
with many more entered by the surgical teams. Questions abound: who should have access to the data produced
by the Registry and how should they use it? How should the results
be reported and in what forum? Cite this article:
We sought to determine if a durable bilayer implant composed of trabecular metal with autologous periosteum on top would be suitable to reconstitute large osteochondral defects. This design would allow for secure implant fixation, subsequent integration and remodeling. Adult sheep were randomly assigned to one of three groups (n = 8/group): 1. trabecular metal/periosteal graft (TMPG), 2. trabecular metal (TM), 3. empty defect (ED). Cartilage and bone healing were assessed macroscopically, biochemically (type II collagen, sulfated glycosaminoglycan (sGAG) and double-stranded DNA (dsDNA) content) and histologically.Objectives
Materials and Methods
We are entering a new era with governmental bodies
taking an increasingly guiding role, gaining control of registries,
demanding direct access with release of open public information
for quality comparisons between hospitals. This review is written
by physicians and scientists who have worked with the Swedish Knee
Arthroplasty Register (SKAR) periodically since it began. It reviews
the history of the register and describes the methods used and lessons
learned. Cite this article:
Accurate characterisation of fractures is essential in fracture management trials. However, this is often hampered by poor inter-observer agreement. This article describes the practicalities of defining the fracture population, based on the Neer classification, within a pragmatic multicentre randomised controlled trial in which surgical treatment was compared with non-surgical treatment in adults with displaced fractures of the proximal humerus involving the surgical neck. The trial manual illustrated the Neer classification of proximal humeral fractures. However, in addition to surgical neck displacement, surgeons assessing patient eligibility reported on whether either or both of the tuberosities were involved. Anonymised electronic versions of baseline radiographs were sought for all 250 trial participants. A protocol, data collection tool and training presentation were developed and tested in a pilot study. These were then used in a formal assessment and classification of the trial fractures by two independent senior orthopaedic shoulder trauma surgeons.Objectives
Methods
We conducted a randomised controlled trial to assess the accuracy
of positioning and alignment of the components in total knee arthroplasty
(TKA), comparing those undertaken using standard intramedullary
cutting jigs and those with patient-specific instruments (PSI). There were 64 TKAs in the standard group and 69 in the PSI group. The post-operative hip-knee-ankle (HKA) angle and positioning
was investigated using CT scans. Deviation of >
3° from the planned
position was regarded as an outlier. The operating time, Oxford
Knee Scores (OKS) and Short Form-12 (SF-12) scores were recorded.Aims
Patients and Methods
Patients from a randomised trial on resurfacing
hip arthroplasty (RHA) (n = 36, 19 males; median age 57 years, 24
to 65) comparing a conventional 28 mm metal-on-metal total hip arthroplasty
(MoM THA) (n = 28, 17 males; median age 59 years, 37 to 65) and
a matched control group of asymptomatic patients with a 32 mm ceramic-on-polyethylene
(CoP) THA (n = 33, 18 males; median age 63 years, 38 to 71) were
cross-sectionally screened with metal artefact reducing sequence-MRI
(MARS-MRI) for pseudotumour formation at a median of 55 months (23
to 72) post-operatively. MRIs were scored by consensus according
to three different classification systems for pseudotumour formation. Clinical scores were available for all patients and metal ion
levels for MoM bearing patients. Periprosthetic lesions with a median volume of 16 mL (1.5 to
35.9) were diagnosed in six patients in the RHA group (17%), one
in the MoM THA group (4%) and six in the CoP group (18%). The classification
systems revealed no clear differences between the groups. Solid
lesions (n = 3) were exclusively encountered in the RHA group. Two patients
in the RHA group and one in the MoM THA group underwent a revision
for pseudotumour formation. There was no statistically significant
relationship between clinical scoring, metal ion levels and periprosthetic
lesions in any of the groups. Periprosthetic fluid collections are seen on MARS-MRI after conventional
CoP THA and RHA and may reflect a soft-tissue collection or effusion. Currently available MRI classification systems seem to score
these collections as pseudotumours, causing an-overestimatation
of the incidence of pseudotumours. Cite this article:
We have observed clinical cases where bone is formed in the overlaying muscle covering surgically created bone defects treated with a hydroxyapatite/calcium sulphate biomaterial. Our objective was to investigate the osteoinductive potential of the biomaterial and to determine if growth factors secreted from local bone cells induce osteoblastic differentiation of muscle cells. We seeded mouse skeletal muscle cells C2C12 on the hydroxyapatite/calcium sulphate biomaterial and the phenotype of the cells was analysed. To mimic surgical conditions with leakage of extra cellular matrix (ECM) proteins and growth factors, we cultured rat bone cells ROS 17/2.8 in a bioreactor and harvested the secreted proteins. The secretome was added to rat muscle cells L6. The phenotype of the muscle cells after treatment with the media was assessed using immunostaining and light microscopy.Objectives
Materials and Methods
The April 2015 Research Roundup360 looks at: MCID in grip strength and distal radial fracture; Experiencing rehab in a trial setting; Electrical stimulation and nerve recovery; Molecular diagnosis of TB?; Acetabular orientation: component and arthritis; Analgesia after knee arthroplasty; Bisphosphonate-associated femoral fractures
The aim of this study was to compare the maximum
laxity conferred by the cruciate-retaining (CR) and posterior-stabilised
(PS) Triathlon single-radius total knee arthroplasty (TKA) for anterior
drawer, varus–valgus opening and rotation in eight cadaver knees
through a defined arc of flexion (0º to 110º). The null hypothesis
was that the limits of laxity of CR- and PS-TKAs are not significantly
different. The investigation was undertaken in eight loaded cadaver knees
undergoing subjective stress testing using a measurement rig. Firstly
the native knee was tested prior to preparation for CR-TKA and subsequently
for PS-TKA implantation. Surgical navigation was used to track maximal
displacements/rotations at 0º, 30º, 60º, 90º and 110° of flexion.
Mixed-effects modelling was used to define the behaviour of the
TKAs. The laxity measured for the CR- and PS-TKAs revealed no statistically
significant differences over the studied flexion arc for the two
versions of TKA. Compared with the native knee both TKAs exhibited
slightly increased anterior drawer and decreased varus-valgus and
internal-external roational laxities. We believe further study is required
to define the clinical states for which the additional constraint
offered by a PS-TKA implant may be beneficial. Cite this article:
In this study we used subject-specific finite
element analysis to investigate the mechanical effects of rotational acetabular
osteotomy (RAO) on the hip joint and analysed the correlation between
various radiological measurements and mechanical stress in the hip
joint. We evaluated 13 hips in 12 patients (two men and ten women, mean
age at surgery 32.0 years; 19 to 46) with developmental dysplasia
of the hip (DDH) who were treated by RAO. Subject-specific finite element models were constructed from
CT data. The centre–edge (CE) angle, acetabular head index (AHI),
acetabular angle and acetabular roof angle (ARA) were measured on
anteroposterior pelvic radiographs taken before and after RAO. The
relationship between equivalent stress in the hip joint and radiological measurements
was analysed. The equivalent stress in the acetabulum decreased from 4.1 MPa
(2.7 to 6.5) pre-operatively to 2.8 MPa (1.8 to 3.6) post-operatively
(p <
0.01). There was a moderate correlation between equivalent
stress in the acetabulum and the radiological measurements: CE angle
(R = –0.645, p <
0.01); AHI (R = –0.603, p <
0.01); acetabular
angle (R = 0.484, p = 0.02); and ARA (R = 0.572, p <
0.01). The equivalent stress in the acetabulum of patients with DDH
decreased after RAO. Correction of the CE angle, AHI and ARA was
considered to be important in reducing the mechanical stress in
the hip joint. Cite this article:
Nylon sutures and skin staples are used commonly in total knee arthroplasty (TKA) surgical wound closure. However, there is no study that compares the wound healing efficacy and patient satisfaction scores of both techniques in the same knee. We randomised 70 patients who underwent primary TKA into two groups. In one group of 34 patients, the skin at the upper half of the wound was closed with skin staples and the lower half of the wound was closed with simple interrupted nylon sutures. In the other group of 36 patients, the skin at the upper half of the wound was closed with nylon stitches and the lower half of the wound was closed with skin staples. We recorded the wound closure time, pain score at the time of stitch removal, wound complication rate, patient satisfaction score, and the Hollander wound evaluation score at the post-operative periods of five days, 14 days, six weeks, three months, and six months. Each half wound was analysed separately.Objectives
Methods
