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 Foot &
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We compared the rate of revision for instability
after total hip replacement (THR) when lipped and non-lipped acetabular
liners were used. We hypothesised that the use of a lipped liner
in a modular uncemented acetabular component reduces the risk of
revision for instability after primary THR. Using data from the
New Zealand Joint Registry, we found that the use of a lipped liner
was associated with a significantly decreased rate of revision for instability
and for all other indications. Adjusting for the size of the femoral
head, the surgical approach and the age and gender of the patient,
this difference remained strongly significant (p <
0.001). We conclude that evidence from the New Zealand registry suggests
that the use of lipped liners with modular uncemented acetabular
components is associated with a decreased rate of revision for instability
after primary THR. Cite this article:
We evaluated the accuracy with which a custom-made
acetabular component could be positioned at revision arthroplasty
of the hip in patients with a Paprosky type 3 acetabular defect. A total of 16 patients with a Paprosky type 3 defect underwent
revision surgery using a custom-made trabecular titanium implant.
There were four men and 12 women with a median age of 67 years (48
to 79). The planned inclination (INCL), anteversion (AV), rotation
and centre of rotation (COR) of the implant were compared with the post-operative
position using CT scans. A total of seven implants were malpositioned in one or more parameters:
one with respect to INCL, three with respect to AV, four with respect
to rotation and five with respect to the COR. To the best of our knowledge, this is the first study in which
CT data acquired for the pre-operative planning of a custom-made
revision acetabular implant have been compared with CT data on the
post-operative position. The results are encouraging. Cite this article:
The April 2015 Hip &
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We assessed the difference in hospital based and early clinical
outcomes between the direct anterior approach and the posterior
approach in patients who undergo total hip arthroplasty (THA). The outcome was assessed in 448 (203 males, 245 females) consecutive
patients undergoing unilateral primary THA after the implementation
of an ‘Enhanced Recovery’ pathway. In all, 265 patients (mean age:
71 years (49 to 89); 117 males and 148 females) had surgery using
the direct anterior approach (DAA) and 183 patients (mean age: 70
years (26 to 100); 86 males and 97 females) using a posterior approach.
The groups were compared for age, gender, American Society of Anesthesiologists
grade, body mass index, the side of the operation, pre-operative
Oxford Hip Score (OHS) and attendance at ‘Joint school’. Mean follow-up
was 18.1 months (one to 50).Aims
Patients and Methods
The objective of this study was to compare the elution characteristics,
antimicrobial activity and mechanical properties of antibiotic-loaded
bone cement (ALBC) loaded with powdered antibiotic, powdered antibiotic
with inert filler (xylitol), or liquid antibiotic, particularly focusing
on vancomycin and amphotericin B. Cement specimens loaded with 2 g of vancomycin or amphotericin
B powder (powder group), 2 g of antibiotic powder and 2 g of xylitol
(xylitol group) or 12 ml of antibiotic solution containing 2 g of
antibiotic (liquid group) were tested.Objectives
Methods
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Bone loss in the proximal tibia and distal femur
is frequently encountered in revision knee replacement surgery.
The various options for dealing with this depend on the extent of
any bone loss. We present our results with the use of cementless
metaphyseal metal sleeves in 103 patients (104 knees) with a mean
follow-up of 43 months (30 to 65). At final follow-up, sleeves in
102 knees had good osseointegration. Two tibial sleeves were revised
for loosening, possibly due to infection. The average pre-operative Oxford Knee Score was 23 (11 to 36)
and this improved to 32 (15 to 46) post-operatively. These early
results encourage us to continue with the technique and monitor
the outcomes in the long term. Cite this article:
A common situation presenting to the orthopaedic
surgeon today is a worn acetabular liner with substantial acetabular
and pelvic osteolysis. The surgeon has many options for dealing
with osteolytic defects. These include allograft, calcium based
substitutes, demineralised bone matrix, or combinations of these
options with or without addition of platelet rich plasma. To date
there are no clinical studies to determine the efficacy of using
bone-stimulating materials in osteolytic defects at the time of
revision surgery and there are surprisingly few studies demonstrating
the clinical efficacy of these treatment options. Even when radiographs
appear to demonstrate incorporation of graft material CT studies
have shown that incorporation is incomplete. The surgeon, in choosing
a graft material for a surgical procedure must take into account
the efficacy, safety, cost and convenience of that material. Cite this article:
We hypothesised that the use of tantalum (Ta)
acetabular components in revision total hip arthroplasty (THA) was protective
against subsequent failure due to infection. We identified 966 patients
(421 men, 545 women and 990 hips) who had undergone revision THA
between 2000 and 2013. The mean follow up was 40.2 months (3 months
to 13.1 years). The mean age of the men and women was 62.3 years
(31 to 90) and 65.1 years (25 to 92), respectively. Titanium (Ti) acetabular components were used in 536 hips while
Ta components were used in 454 hips. In total, 73 (7.3%) hips experienced
subsequent acetabular failure. The incidence of failure was lower
in the Ta group at 4.4% (20/454) compared with 9.9% (53/536) in
the Ti group (p <
0.001, odds ratio 2.38; 95% CI 1.37 to 4.27).
Among the 144 hips (64 Ta, 80 Ti) for which revision had been performed
because of infection, failure due to a subsequent infection was
lower in the Ta group at 3.1% (2/64) compared with 17.5% (14/80)
for the Ti group (p = 0.006). Thus, the use of Ta acetabular components during revision THA
was associated with a lower incidence of failure from all causes
and Ta components were associated with a lower incidence of subsequent
infection when used in patients with periprosthetic joint infection. Cite this article:
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:
To compare radiographic failure and re-operation rates of anatomical
coracoclavicular (CC) ligament reconstructional techniques with
non-anatomical techniques after chronic high grade acromioclavicular
(AC) joint injuries. We reviewed chronic AC joint reconstructions within a region-wide
healthcare system to identify surgical technique, complications,
radiographic failure and re-operations. Procedures fell into four
categories: Aims
Patients and Methods
Glenoid bone loss can be a challenging problem when revising
a shoulder arthroplasty. Precise pre-operative planning based on
plain radiographs or CT scans is essential. We have investigated
a new radiological classification system to describe the degree
of medialisation of the bony glenoid and that will indicate the
amount of bone potentially available for supporting a glenoid component.
It depends on the relationship between the most medial part of the
articular surface of the glenoid with the base of the coracoid process
and the spinoglenoid notch: it classifies the degree of bone loss
into three types. It also attempts to predict the type of glenoid reconstruction
that may be possible (impaction bone grafting, structural grafting
or simple non-augmented arthroplasty) and gives guidance about whether
a pre-operative CT scan is indicated. Inter-method reliability between plain radiographs and CT scans
was assessed retrospectively by three independent observers using
data from 39 randomly selected patients. Inter-observer reliability and test-retest reliability was tested
on the same cohort using Cohen's kappa statistics. Correlation of
the type of glenoid with the Constant score and its pain component
was analysed using the Kruskal-Wallis method on data from 128 patients.
Anatomical studies of the scapula were reviewed to explain the findings.Aims
Patients and Methods
Metaphyseal bone loss is common with revision
total knee replacement (RTKR). Using the Anderson Orthopaedic Research
Institute (AORI) classification, type 2-B and type 3 defects usually
require large metal blocks, bulk structural allograft or highly
porous metal cones. Tibial and femoral trabecular metal metaphyseal
cones are a unique solution for large bone defects. These cones
substitute for bone loss, improve metaphyseal fixation, help correct
malalignment, restore the joint line and may permit use of a shorter
stem. The technique for insertion involves sculpturing of the remaining
bone with a high speed burr and rasp, followed by press-fit of the
cone into the metaphysis. The fixation and osteoconductive properties
of the porous cone outer surface allow ingrowth and encourage long-term
biological fixation. The revision knee component is then cemented
into the porous cone inner surface, which provides superior fixation
compared with cementing into native but deficient metaphyseal bone.
The advantages of the cone compared with allograft include: technical
ease, biological fixation, no resorption, and possibly a lower risk
of infection. The disadvantages include: difficult extraction and
relatively short-term follow-up. Several studies using cones report
promising short-term results for the reconstruction of large bone
defects in RTKR. Cite this article:
The continual cycle of bone formation and resorption
is carried out by osteoblasts, osteocytes, and osteoclasts under
the direction of the bone-signaling pathway. In certain situations
the host cycle of bone repair is insufficient and requires the assistance
of bone grafts and their substitutes. The fundamental properties
of a bone graft are osteoconduction, osteoinduction, osteogenesis,
and structural support. Options for bone grafting include autogenous
and allograft bone and the various isolated or combined substitutes
of calcium sulphate, calcium phosphate, tricalcium phosphate, and
coralline hydroxyapatite. Not all bone grafts will have the same
properties. As a result, understanding the requirements of the clinical
situation and specific properties of the various types of bone grafts
is necessary to identify the ideal graft. We present a review of
the bone repair process and properties of bone grafts and their
substitutes to help guide the clinician in the decision making process. Cite this article:
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