Conventional cemented acetabular components are
reported to have a high rate of failure when implanted into previously
irradiated bone. We recommend the use of a cemented reconstruction
with the addition of an acetabular reinforcement cross to improve
fixation. We reviewed a cohort of 45 patients (49 hips) who had undergone
irradiation of the pelvis and a cemented total hip arthroplasty
(THA) with an acetabular reinforcement cross. All hips had received
a minimum dose of 30 Gray (Gy) to treat a primary nearby tumour
or metastasis. The median dose of radiation was 50 Gy (Q1 to Q3:
45 to 60; mean: 49.57, 32 to 72). The mean follow-up after THA was 51 months (17 to 137). The cumulative
probability of revision of the acetabular component for a mechanical
reason was 0% (0 to 0%) at 24 months, 2.9% (0.2 to 13.3%) at 60
months and 2.9% (0.2% to 13.3%) at 120 months, respectively. One
hip was revised for mechanical failure and three for infection. Cemented acetabular components with a reinforcement cross provide
good medium-term fixation after pelvic irradiation. These patients
are at a higher risk of developing infection of their THA. Cite this article:
This paper reviews the current literature concerning the main clinical factors which can impair the healing of fractures and makes recommendations on avoiding or minimising these in order to optimise the outcome for patients. The clinical implications are described.
Cancellous allograft bone chips are commonly
used in the reconstruction of defects in bone after removal of benign tumours.
We investigated the MRI features of grafted bone chips and their
change over time, and compared them with those with recurrent tumour.
We retrospectively reviewed 66 post-operative MRIs from 34 patients
who had undergone curettage and grafting with cancellous bone chips
to fill the defect after excision of a tumour. All grafts showed
consistent features at least six months after grafting: homogeneous
intermediate or low signal intensities with or without scattered
hyperintense foci (speckled hyperintensities) on T1 images; high
signal intensities with scattered hypointense foci (speckled hypointensities)
on T2 images, and peripheral rim enhancement with or without central
heterogeneous enhancements on enhanced images. Incorporation of
the graft occurred from the periphery to the centre, and was completed
within three years. Recurrent lesions consistently showed the same signal
intensities as those of pre-operative MRIs of the primary lesions.
There were four misdiagnoses, three of which were chondroid tumours. We identified typical MRI features and clarified the incorporation
process of grafted cancellous allograft bone chips. The most important
characteristics of recurrent tumours were that they showed the same
signal intensities as the primary tumours. It might sometimes be
difficult to differentiate grafted cancellous allograft bone chips
from a recurrent chondroid tumour. Cite this article:
Curettage and packing with polymethylmethacrylate cement is a routine treatment for giant-cell tumour (GCT) of bone. We performed an We found that the cytotoxic effect of eluted drugs depended on their concentration and the time interval, with even the lowest dose of each drug demonstrating an acceptable rate of cytotoxicity. Even in low doses, cytotoxic drugs mixed with polymethylmethacrylate cement could therefore be considered as effective local adjuvant treatment for GCTs.
A silver-containing hydroxyapatite (Ag-HA) coating has been developed using thermal spraying technology. We evaluated the osteoconductivity of this coating on titanium (Ti) implants in rat tibiae in relation to bacterial infection in joint replacement. At 12 weeks, the mean affinity indices of bone formation of a Ti, an HA, a 3%Ag-HA and a 50%Ag-HA coating were 97.3%, 84.9%, 81.0% and 40.5%, respectively. The mean affinity indices of bone contact of these four coatings were 18.8%, 83.7%, 77.2% and 40.5%, respectively. The indices of bone formation and bone contact around the implant of the 3%Ag-HA coating were similar to those of the HA coating, and no significant differences were found between them (bone formation, p = 0.99; bone contact, p = 0.957). However, inhibition of bone formation was observed with the 50%Ag-HA coating. These results indicate that the 3%Ag-HA coating has low toxicity and good osteoconductivity, and that the effect of silver toxicity on osteoconductivity depends on the dose.
The literature on fracture repair has been reviewed. The traditional concepts of delayed and nonunion have been examined in terms of the phased and balanced anabolic and catabolic responses in bone repair. The role of medical manipulation of these inter-related responses in the fracture healing have been considered.
Although mechanical stabilisation has been a hallmark of orthopaedic surgical management, orthobiologics are now playing an increasing role. Platelet-rich plasma (PRP) is a volume of plasma fraction of autologous blood having platelet concentrations above baseline. The platelet α granules are rich in growth factors that play an essential role in tissue healing, such as transforming growth factor-β, vascular endothelial growth factor, and platelet-derived growth factor. PRP is used in various surgical fields to enhance bone and soft-tissue healing by placing supraphysiological concentrations of autologous platelets at the site of tissue damage. The easily obtainable PRP and its possible beneficial outcome hold promise for new regenerative treatment approaches. The aim of this literature review was to describe the bioactivities of PRP, to elucidate the different techniques for PRP preparation, to review animal and human studies, to evaluate the evidence regarding the use of PRP in trauma and orthopaedic surgery, to clarify risks, and to provide guidance for future research.
We compared the clinical and radiographic results
of total ankle replacement (TAR) performed in non-diabetic and diabetic
patients. We identified 173 patients who underwent unilateral TAR
between 2004 and 2011 with a minimum of two years’ follow-up. There
were 88 male (50.9%) and 85 female (49.1%) patients with a mean
age of 66 years ( The mean AOS and AOFAS scores were significantly better in the
non-diabetic group (p = 0.018 and p = 0.038, respectively). In all,
nine TARs (21%) in the diabetic group had clinical failure at a
mean follow-up of five years (24 to 109), which was significantly
higher than the rate of failure of 15 (11.6%) in the non-diabetic
group (p = 0.004). The uncontrolled diabetic subgroup had a significantly
poorer outcome than the non-diabetic group (p = 0.02), and a higher
rate of delayed wound healing. The incidence of early-onset osteolysis was higher in the diabetic
group than in the non-diabetic group (p = 0.02). These results suggest
that diabetes mellitus, especially with poor glycaemic control,
negatively affects the short- to mid-term outcome after TAR. Cite this article:
Bacterial infection in orthopaedic surgery can be devastating, and is associated with significant morbidity and poor functional outcomes, which may be improved if high concentrations of antibiotics can be delivered locally over a prolonged period of time. The two most widely used methods of doing this involve antibiotic-loaded polymethylmethacrylate or collagen fleece. The former is not biodegradable and is a surface upon which secondary bacterial infection may occur. Consequently, it has to be removed once treatment has finished. The latter has been used successfully as an adjunct to systemic antibiotics, but cannot effect a sustained release that would allow it to be used on its own, thereby avoiding systemic toxicity. This review explores the newer biodegradable carrier systems which are currently in the experimental phase of development and which may prove to be more effective in the treatment of osteomyelitis.
Four uncemented Symax hip stems were extracted at three weeks and nine, 13 and 32 months, respectively, for reasons other than loosening. The reasons for implant removal were infection in two cases, recurrent dislocation in one and acetabular fracture in one. They were analysed to assess the effect and behaviour of an electrochemically deposited, completely resorbable biomimetic BONIT-hydroxyapatite (HA) coating (proximal part) and a DOTIZE surface treatment (distal part) using qualitative histology, quantitative histomorphometry and scanning electron microscopy (SEM). Early and direct bone-implant bonding with signs of active remodelling of bone and the HA coating were demonstrated by histology and SEM. No loose BONIT-HA particles or delamination of the coating were observed, and there was no inflammation or fibrous interposition at the interface. Histomorphometry showed bone-implant contact varying between 26.5% at three weeks and 83.5% at 13 months at the HA-coated implant surface. The bone density in the area of investigation was between 24.6% at three weeks and 41.1% at 32 months. The DOTIZE surface treatment of the distal part of the stem completely prevented tissue and bone apposition in all cases, thereby optimising proximal stress transfer. The overall features of this implant, in terms of geometry and surface texture, suggest a mechanically stable design with a highly active biomimetic coating, resulting in rapid and extensive osseo-integration, exclusively in the metaphyseal part of the stem. Early remodelling of the HA coating does not seem to have a detrimental effect on short-term bone-implant coupling. There were no adverse effects identified from either the BONIT-HA coating or the DOTIZE surface treatment.
There is increasing application of bone morphogenetic proteins
(BMPs) owing to their role in promoting fracture healing and bone
fusion. However, an optimal delivery system has yet to be identified.
The aims of this study were to synthesise bioactive BMP-2, combine
it with a novel α-tricalcium phosphate/poly(D,L-lactide-co-glycolide)
(α-TCP/PLGA) nanocomposite and study its release from the composite. BMP-2 was synthesised using an Objectives
Methods
Electromagnetic fields (EMF) are widely used in musculoskeletal
disorders. There are indications that EMF might also be effective
in the treatment of osteoporosis. To justify clinical follow-up
experiments, we examined the effects of EMF on bone micro-architectural
changes in osteoporotic and healthy rats. Moreover, we tested the
effects of EMF on fracture healing. EMF (20 Gauss) was examined in rats (aged 20 weeks), which underwent
an ovariectomy (OVX; n = 8) or sham-ovariectomy (sham-OVX; n = 8).
As a putative positive control, all rats received bilateral fibular
osteotomies to examine the effects on fracture healing. Treatment
was applied to one proximal lower leg (three hours a day, five days
a week); the lower leg was not treated and served as a control.
Bone architectural changes of the proximal tibia and bone formation
around the osteotomy were evaluated using Objectives
Methods
Osteoradionecrosis is a rare but recognised complication of radiotherapy. Cases have been described in the cervical spine following treatment for head and neck malignancies up to 25 years after administration of radiotherapy. We present a rare case of osteoradionecrosis affecting the L5 and S1 vertebral bodies in a 58-year-old woman who presented with low back pain 25 years after undergoing a hysterectomy with adjuvant radiotherapy for cancer of the cervix.
The success of long-term transcutaneous implants
depends on dermal attachment to prevent downgrowth of the epithelium
and infection. Hydroxyapatite (HA) coatings and fibronectin (Fn)
have independently been shown to regulate fibroblast activity and
improve attachment. In an attempt to enhance this phenomenon we
adsorbed Fn onto HA-coated substrates. Our study was designed to
test the hypothesis that adsorption of Fn onto HA produces a surface
that will increase the attachment of dermal fibroblasts better than
HA alone or titanium alloy controls. Iodinated Fn was used to investigate the durability of the protein
coating and a bioassay using human dermal fibroblasts was performed
to assess the effects of the coating on cell attachment. Cell attachment
data were compared with those for HA alone and titanium alloy controls
at one, four and 24 hours. Protein attachment peaked within one
hour of incubation and the maximum binding efficiency was achieved
with an initial droplet of 1000 ng. We showed that after 24 hours
one-fifth of the initial Fn coating remained on the substrates,
and this resulted in a significant, three-, four-, and sevenfold
increase in dermal fibroblast attachment strength compared to uncoated controls
at one, four and 24 hours, respectively.
For the treatment of ununited fractures, we developed
a system of delivering magnetic labelled mesenchymal stromal cells
(MSCs) using an extracorporeal magnetic device. In this study, we
transplanted ferucarbotran-labelled and luciferase-positive bone
marrow-derived MSCs into a non-healing femoral fracture rat model
in the presence of a magnetic field. The biological fate of the
transplanted MSCs was observed using luciferase-based bioluminescence
imaging and we found that the number of MSC derived photons increased
from day one to day three and thereafter decreased over time. The
magnetic cell delivery system induced the accumulation of photons at
the fracture site, while also retaining higher photon intensity
from day three to week four. Furthermore, radiological and histological
findings suggested improved callus formation and endochondral ossification.
We therefore believe that this delivery system may be a promising
option for bone regeneration.
This preliminary study evaluates a combination
of bone morphogenetic protein (BMP)-7 and non-vascularised autologous
fibular grafting (AFG) for the treatment of osteonecrosis of the
femoral head. BMP-7/AFG combination was applied in seven pre-collapse femoral
heads (five Steinberg stage II, two stage III) in six patients.
Pre- and post-operative evaluation included clinical (Harris hip
score (HHS), visual analogue scale (VAS) for pain) and radiological
assessment (radiographs, quantitative CT) at a mean follow-up of
4 years (2 to 5.5). A marked improvement of function (mean HHS increase of 49.2)
and decrease of pain level (mean VAS decrease of 5) as well as retention
of the sphericity of the femoral head was noted in five hips at
the latest follow-up, while signs of consolidation were apparent
from the third post-operative month. One patient (two hips) required
bilateral total hip replacement at one year post-operatively. In
the series as a whole, quantitative-CT evaluation revealed similar densities
between affected and normal bone. Heterotopic ossification was observed
in four hips, without compromise of the clinical outcome. In this limited series AFG/BMP-7 combination proved a safe and
effective method for the treatment of femoral head osteonecrosis,
leading to early consolidation of the AFG and preventing collapse
in five of seven hips, while the operative time and post-operative
rehabilitation period were much shorter compared with free vascularised fibular
grafts. Cite this article:
We examined osteochondral autografts, obtained at a mean of 19.5 months (3 to 48) following extracorporeal irradiation and re-implantation to replace bone defects after removal of tumours. The specimens were obtained from six patients (mean age 13.3 years (10 to 18)) and consisted of articular cartilage (five), subchondral bone (five), external callus (one) and tendon (one). The tumour cells in the grafts were eradicated by a single radiation dose of 60 Gy. In three cartilage specimens, viable chondrocytes were detected. The survival of chondrocytes was confirmed with S-100 protein staining. Three specimens from the subchondral region and a tendon displayed features of regeneration. Callus was seen at the junction between host and irradiated bone.
We report our experience using a biodegradable
calcium sulphate antibiotic carrier containing tobramycin in the surgical
management of patients with chronic osteomyelitis. The patients
were reviewed to determine the rate of recurrent infection, the
filling of bony defects, and any problems with wound healing. A
total of 193 patients (195 cases) with a mean age of 46.1 years
(16.1 to 82.0) underwent surgery. According to the Cierny–Mader
classification of osteomyelitis there were 12 type I, 1 type II,
144 type III and 38 type IV cases. The mean follow-up was 3.7 years (1.3
to 7.1) with recurrent infection occurring in 18 cases (9.2%) at
a mean of 10.3 months post-operatively (1 to 25.0). After further
treatment the infection resolved in 191 cases (97.9%). Prolonged
wound ooze (longer than two weeks post-operatively) occurred in
30 cases (15.4%) in which there were no recurrent infection. Radiographic
assessment at final follow-up showed no filling of the defect with
bone in 67 (36.6%), partial filling in 108 (59.0%) and complete filling
in eight (4.4%). A fracture occurred in nine (4.6%) of the treated
osteomyelitic segments at a mean of 1.9 years (0.4 to 4.9) after
operation. We conclude that Osteoset T is helpful in the management of patients
with chronic osteomyelitis, but the filling of the defect in bone
is variable. Prolonged wound ooze is usually self-limiting and not
associated with recurrent infection. Cite this article:
The February 2014 Hip &
Pelvis Roundup360 looks at: length of stay; cementless metaphyseal fixation; mortality trends in over 400,000 total hip replacements; antibiotics in hip fracture surgery; blood supply to the femoral head after dislocation; resurfacing and THR in metal-on-metal replacement; diabetes and hip replacement; bone remodelling over two decades following hip replacement; and whether bisphosphonates affect acetabular fixation.
The feasibility of bone transport with bone substitute and the factors which are essential for a successful bone transport are unknown. We studied six groups of 12 Japanese white rabbits. Groups A to D received cylindrical autologous bone segments and groups E and F hydroxyapatite prostheses. The periosteum was preserved in group A so that its segments had a blood supply, cells, proteins and scaffold. Group B had no blood supply. Group C had proteins and scaffold and group D had only scaffold. Group E received hydroxyapatite loaded with recombinant human bone morphogenetic protein-2 and group F had hydroxyapatite alone. Distraction osteogenesis occurred in groups A to C and E which had osteo-conductive transport segments loaded with osteo-inductive proteins. We conclude that scaffold and proteins are essential for successful bone transport, and that bone substitute can be used to regenerate bone.