Patients with neuromuscular imbalance who require
total hip arthroplasty (THA) present particular technical problems
due to altered anatomy, abnormal bone stock, muscular imbalance
and problems of rehabilitation. In this systematic review, we studied articles dealing with THA
in patients with neuromuscular imbalance, published before April
2017. We recorded the demographics of the patients and the type
of neuromuscular pathology, the indication for surgery, surgical
approach, concomitant soft-tissue releases, the type of implant
and bearing, pain and functional outcome as well as complications
and survival. Recent advances in THA technology allow for successful outcomes
in these patients. Our review suggests excellent benefits for pain
relief and good functional outcome might be expected with a modest
risk of complication. Cite this article:
We wished to investigate the influence of metal debris exposure
on the subsequent immune response and resulting soft-tissue injury
following metal-on-metal (MoM) hip arthroplasty. Some reports have
suggested that debris generated from the head-neck taper junction
is more destructive than equivalent doses from metal bearing surfaces. We investigated the influence of the source and volume of metal
debris on chromium (Cr) and cobalt (Co) concentrations in corresponding
blood and hip synovial fluid samples and the observed agglomerated
particle sizes in excised tissues using multiple regression analysis
of prospectively collected data. A total of 199 explanted MoM hips
(177 patients; 132 hips female) were analysed to determine rates
of volumetric wear at the bearing surfaces and taper junctions. Aims
Patients and Methods
Patient-specific (PS) implantation surgical technology has been introduced in recent years and a gradual increase in the associated number of surgical cases has been observed. PS technology uses a patient’s own geometry in designing a medical device to provide minimal bone resection with improvement in the prosthetic bone coverage. However, whether PS unicompartmental knee arthroplasty (UKA) provides a better biomechanical effect than standard off-the-shelf prostheses for UKA has not yet been determined, and still remains controversial in both biomechanical and clinical fields. Therefore, the aim of this study was to compare the biomechanical effect between PS and standard off-the-shelf prostheses for UKA. The contact stresses on the polyethylene (PE) insert, articular cartilage and lateral meniscus were evaluated in PS and standard off-the-shelf prostheses for UKA using a validated finite element model. Gait cycle loading was applied to evaluate the biomechanical effect in the PS and standard UKAs.Objectives
Methods
Cervical spondylosis is often accompanied by dizziness. It has
recently been shown that the ingrowth of Ruffini corpuscles into
diseased cervical discs may be related to cervicogenic dizziness.
In order to evaluate whether cervicogenic dizziness stems from the
diseased cervical disc, we performed a prospective cohort study
to assess the effectiveness of anterior cervical discectomy and
fusion on the relief of dizziness. Of 145 patients with cervical spondylosis and dizziness, 116
underwent anterior cervical decompression and fusion and 29 underwent
conservative treatment. All were followed up for one year. The primary
outcomes were measures of the intensity and frequency of dizziness.
Secondary outcomes were changes in the modified Japanese Orthopaedic
Association (mJOA) score and a visual analogue scale score for neck
pain.Aims
Patients and Methods
Adverse reaction to wear and corrosion debris
is a cause for concern in total hip arthroplasty (THA). Modular junctions
are a potential source of such wear products and are associated
with secondary pseudotumour formation. We present a consecutive series of 17 patients treated at our
unit for this complication following metal-on-highly cross-linked
polyethylene (MoP) THA. We emphasise the risk of misdiagnosis as
infection, and present the aggregate laboratory results and pathological
findings in this series. The clinical presentation was pain, swelling or instability.
Solid, cystic and mixed soft-tissue lesions were noted on imaging
and confirmed intra-operatively. Corrosion at the head–neck junction
was noted in all cases. No bacteria were isolated on multiple pre-
and intra-operative samples yet the mean erythrocyte sedimentation
rate was 49 (9 to 100) and C-reactive protein 32 (0.6 to 106) and
stromal polymorphonuclear cell counts were noted in nine cases. Adverse soft–tissue reactions can occur in MoP THA owing to corrosion
products released from the head–neck junction. The diagnosis should
be carefully considered when investigating pain after THA. This
may avoid the misdiagnosis of periprosthetic infection with an unidentified
organism and mitigate the unnecessary management of these cases
with complete single- or two-stage exchange. Cite this article:
The treatment of bone loss in revision total
knee arthroplasty has evolved over the past decade. While the management
of small to moderate sized defects has demonstrated good results
with a variety of traditional techniques (cement and screws, small
metal augments, impaction bone grafting or modular stems), the treatment of
severe defects continues to be problematic. The use of a structural
allograft has declined in recent years due to an increased failure
rate with long-term follow-up and with the introduction of highly
porous metal augments that emphasise biological metaphyseal fixation.
Recently published mid-term results on the use of tantalum cones
in patients with severe bone loss has reaffirmed the success of
this treatment strategy. Cite this article:
Following the resection of an extensive amount of bone in the
treatment of a tumour, the residual segment may be insufficient
to accept a standard length intramedullary cemented stem. Short-stemmed
endoprostheses conceivably have an increased risk of aseptic loosening.
Extra-cortical plates have been added to minimise this risk by supplementing
fixation. The aim of this study was to investigate the survivorship
of short-stemmed endoprostheses and extra-cortical plates. The study involved 37 patients who underwent limb salvage surgery
for a primary neoplasm of bone between 1998 and 2013. Endoprosthetic
replacement involved the proximal humerus in nine, the proximal
femur in nine, the distal femur in 13 and the proximal tibia in
six patients. There were 12 primary (32%) and 25 revision procedures (68%).
Implant survivorship was compared with matched controls. The amount
of bone that was resected was >
70% of its length and statistically
greater than the standard control group at each anatomical site.Aims
Patients and Methods
We present a case series of ten metal-on-polyethylene total hip
arthroplasties (MoP THAs) with delayed dislocation associated with
unrecognised adverse local tissue reaction due to corrosion at the
trunnion and pseudotumour formation. The diagnosis was not suspected in nine of the ten patients (six
female/four male; mean age 66 years), despite treatment in a specialist
unit (mean time from index surgery to revision was 58 months, 36
to 84). It was identified at revision surgery and subsequently confirmed
by histological examination of resected tissue. Pre-operative assessment
and culture results ruled out infection. A variety of treatment
strategies were used, including resection of the pseudotumour and
efforts to avoid recurrent dislocation. Aims
Methods
The aim of this study was to investigate the outcomes of Vancouver
type B2 and B3 fractures by performing a systematic review of the
methods of surgical treatment which have been reported. A systematic search was performed in Ovid MEDLINE, Embase and
the Cochrane Central Register of Controlled Trials. For inclusion,
studies required a minimum of ten patients with a Vancouver type
B2 and/or ten patients with a Vancouver type B3 fracture, a minimum
mean follow-up of two years and outcomes which were matched to the type
of fracture. Studies were also required to report the rate of re-operation
as an outcome measure. The protocol was registered in the PROSPERO
database. Aims
Materials and Methods
Dual mobility cups have two points of articulation,
one between the shell and the polyethylene (external bearing) and
one between the polyethylene and the femoral head (internal bearing).
Movement occurs at the inner bearing; the outer bearing only moves
at extremes of movement. Dislocation after total hip arthroplasty (THA) is a cause of
much morbidity and its treatment has significant cost implications.
Dual mobility cups provide an increased range of movement and a
may reduce the risk of dislocation. This paper reviews the use of these cups in THA, particularly
where stability is an issue. Dual mobility cups may be of benefit
in primary THA in patients at a high risk of dislocation, such as
those who are older with increased comorbidities and a higher American
Association of Anesthesiology grade and those with a neuromuscular
disease. They may be used at revision surgery where the risk of
dislocation is high, such as in patients with many prior dislocations,
or those with abductor deficiency. They may also be used in THA
for displaced fractures of the femoral neck, which has a notoriously
high rate of dislocation. Cite this article:
Instability remains a challenging problem in both primary and
revision total hip arthroplasty (THA). Dual mobility components
confer increased stability, but there are concerns about the unique
complications associated with these designs, as well as the long-term
survivorship. We performed a systematic review of all English language articles
dealing with dual mobility THAs published between 2007 and 2016
in the MEDLINE and Embase electronic databases. A total of 54 articles
met inclusion criteria for the final analysis of primary and revision
dual mobility THAs and dual mobility THAs used in the treatment
of fractures of the femoral neck. We analysed the survivorship and
rates of aseptic loosening and of intraprosthetic and extra-articular
dislocation.Aims
Materials and Methods
Secondary fracture healing is strongly influenced by the stiffness of the bone-fixator system. Biomechanical tests are extensively used to investigate stiffness and strength of fixation devices. The stiffness values reported in the literature for locked plating, however, vary by three orders of magnitude. The aim of this study was to examine the influence that the method of restraint and load application has on the stiffness produced, the strain distribution within the bone, and the stresses in the implant for locking plate constructs. Synthetic composite bones were used to evaluate experimentally the influence of four different methods of loading and restraining specimens, all used in recent previous studies. Two plate types and three screw arrangements were also evaluated for each loading scenario. Computational models were also developed and validated using the experimental tests.Objectives
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
Massive endoprostheses rely on extra-cortical bone bridging (ECBB)
to enhance fixation. The aim of this study was to investigate the
role of selective laser sintered (SLS) porous collars in augmenting
the osseointegration of these prostheses. The two novel designs of porous SLS collars, one with small pores
(Ø700 μm, SP) and one with large pores (Ø1500 μm, LP), were compared
in an ovine tibial diaphyseal model. Osseointegration of these collars
was compared with that of a clinically used solid, grooved design
(G). At six months post-operatively, the ovine tibias were retrieved and
underwent radiological and histological analysis.Aims
Materials and Methods
To investigate the longevity of uncemented fixation of a femoral
component in total hip arthroplasty (THA) in patients with Dorr
type C proximal femoral morphology. A total of 350 consecutive uncemented THA in 320 patients were
performed between 1983 and 1987, by a single surgeon using the Taperloc
femoral component. The 63 patients (68 hips) with Dorr type C proximal
femoral morphology were the focus of this review. The mean age of
the patients was 69 years (24 to 88) and mean follow-up was 16.6
years (ten to 29). Survival analysis included eight patients (eight
hips) who died without undergoing revision surgery prior to obtaining
ten years follow-up. All 55 surviving patients (60 hips) were available
for clinical assessment and radiographic review. As a comparator
group, the survival and implant fixation in the remaining 282 THAs
(257 patients) with Dorr type A and B morphology were evaluated.
The mean age of these patients was 52 years (20 to 82).Aims
Patients and Methods
Hips with metal-on-metal total hip arthroplasty (MoM THA) have a high rate of adverse local tissue reactions (ALTR), often associated with hypersensitivity reactions. Dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) measures tissue perfusion with the parameter Ktrans (volume transfer constant of contrast agent). Our purpose was 1) to evaluate the feasibility of DCE-MRI in patients with THA and 2) to compare DCE-MRI in patients with MoM bearings with metal-on-polyethylene (MoP) bearings, hypothesising that the perfusion index Ktrans in hips with MoM THA is higher than in hips with MoP THA. In this pilot study, 16 patients with primary THA were recruited (eight MoM, eight MoP). DCE-MRI of the hip was performed at 1.5 Tesla (T). For each patient, Ktrans was computed voxel-by-voxel in all tissue lateral to the bladder. The mean Ktrans for all voxels was then calculated. These values were compared with respect to implant type and gender, and further correlated with clinical parameters.Objectives
Methods
This study reports on a secondary exploratory analysis of the early clinical outcomes of a randomised clinical trial comparing robotic arm-assisted unicompartmental knee arthroplasty (UKA) for medial compartment osteoarthritis of the knee with manual UKA performed using traditional surgical jigs. This follows reporting of the primary outcomes of implant accuracy and gait analysis that showed significant advantages in the robotic arm-assisted group. A total of 139 patients were recruited from a single centre. Patients were randomised to receive either a manual UKA implanted with the aid of traditional surgical jigs, or a UKA implanted with the aid of a tactile guided robotic arm-assisted system. Outcome measures included the American Knee Society Score (AKSS), Oxford Knee Score (OKS), Forgotten Joint Score, Hospital Anxiety Depression Scale, University of California at Los Angeles (UCLA) activity scale, Short Form-12, Pain Catastrophising Scale, somatic disease (Primary Care Evaluation of Mental Disorders Score), Pain visual analogue scale, analgesic use, patient satisfaction, complications relating to surgery, 90-day pain diaries and the requirement for revision surgery.Objectives
Methods
Osteosynthesis of anterior pubic ramus fractures using one large-diameter screw can be challenging in terms of both surgical procedure and fixation stability. Small-fragment screws have the advantage of following the pelvic cortex and being more flexible. The aim of the present study was to biomechanically compare retrograde intramedullary fixation of the superior pubic ramus using either one large- or two small-diameter screws. A total of 12 human cadaveric hemipelvises were analysed in a matched pair study design. Bone mineral density of the specimens was 68 mgHA/cm3 (standard deviation (Objectives
Materials and Methods
We present a case series of five patients who had revision surgery
following magnetic controlled growing rods (MGCR) for early onset
scoliosis. Metallosis was found during revision in four out of five
patients and we postulated a mechanism for rod failure based on
retrieval analysis. Retrieval analysis was performed on the seven explanted rods.
The mean duration of MCGR from implantation to revision was 35 months
(17 to 46). The mean age at revision was 12 years (7 to 15; four
boys, one girl).Aims
Patients and Methods
