Peri-prosthetic osteolysis and subsequent aseptic
loosening is the most common reason for revising total hip replacements.
Wear particles originating from the prosthetic components interact
with multiple cell types in the peri-prosthetic region resulting
in an inflammatory process that ultimately leads to peri-prosthetic
bone loss. These cells include macrophages, osteoclasts, osteoblasts
and fibroblasts. The majority of research in peri-prosthetic osteolysis
has concentrated on the role played by osteoclasts and macrophages.
The purpose of this review is to assess the role of the osteoblast
in peri-prosthetic osteolysis. In peri-prosthetic osteolysis, wear particles may affect osteoblasts
and contribute to the osteolytic process by two mechanisms. First,
particles and metallic ions have been shown to inhibit the osteoblast
in terms of its ability to secrete mineralised bone matrix, by reducing
calcium deposition, alkaline phosphatase activity and its ability
to proliferate. Secondly, particles and metallic ions have been
shown to stimulate osteoblasts to produce pro inflammatory mediators Cite this article:
Injury to the anterior cruciate ligament (ACL)
is one of the most devastating and frequent injuries of the knee. Surgical
reconstruction is the current standard of care for treatment of
ACL injuries in active patients. The widespread adoption of ACL
reconstruction over primary repair was based on early perception
of the limited healing capacity of the ACL. Although the majority
of ACL reconstruction surgeries successfully restore gross joint stability,
post-traumatic osteoarthritis is commonplace following these injuries,
even with ACL reconstruction. The development of new techniques
to limit the long-term clinical sequelae associated with ACL reconstruction
has been the main focus of research over the past decades. The improved
knowledge of healing, along with recent advances in tissue engineering
and regenerative medicine, has resulted in the discovery of novel
biologically augmented ACL-repair techniques that have satisfactory
outcomes in preclinical studies. This instructional review provides
a summary of the latest advances made in ACL repair. Cite this article:
We performed a systematic review and meta-analysis
of modern total ankle replacements (TARs) to determine the survivorship,
outcome, complications, radiological findings and range of movement,
in patients with end-stage osteoarthritis (OA) of the ankle who
undergo this procedure. We used the methodology of the Cochrane Collaboration,
which uses risk of bias profiling to assess the quality of papers
in favour of a domain-based approach. Continuous outcome scores
were pooled across studies using the generic inverse variance method
and the random-effects model was used to incorporate clinical and
methodological heterogeneity. We included 58 papers (7942 TARs)
with an interobserver reliability (Kappa) for selection, performance,
attrition, detection and reporting bias of between 0.83 and 0.98.
The overall survivorship was 89% at ten years with an annual failure
rate of 1.2% (95% confidence interval (CI) 0.7 to 1.6). The mean
American Orthopaedic Foot and Ankle Society score changed from 40 (95%
CI 36 to 43) pre-operatively to 80 (95% CI 76 to 84) at a mean follow-up
of 8.2 years (7 to 10) (p <
0.01). Radiolucencies were identified
in up to 23% of TARs after a mean of 4.4 years (2.3 to 9.6). The
mean total range of movement improved from 23° (95% CI 19 to 26)
to 34° (95% CI 26 to 41) (p = 0.01). Our study demonstrates that TAR has a positive impact on patients’
lives, with benefits lasting ten years, as judged by improvement
in pain and function, as well as improved gait and increased range
of movement. However, the quality of evidence is weak and fraught
with biases and high quality randomised controlled trials are required
to compare TAR with other forms of treatment such as fusion. Cite this article:
The treatment of osteochondral lesions and osteoarthritis
remains an ongoing clinical challenge in orthopaedics. This review
examines the current research in the fields of cartilage regeneration,
osteochondral defect treatment, and biological joint resurfacing, and
reports on the results of clinical and pre-clinical studies. We
also report on novel treatment strategies and discuss their potential
promise or pitfalls. Current focus involves the use of a scaffold
providing mechanical support with the addition of chondrocytes or mesenchymal
stem cells (MSCs), or the use of cell homing to differentiate the
organism’s own endogenous cell sources into cartilage. This method
is usually performed with scaffolds that have been coated with a
chemotactic agent or with structures that support the sustained
release of growth factors or other chondroinductive agents. We also
discuss unique methods and designs for cell homing and scaffold
production, and improvements in biological joint resurfacing. There
have been a number of exciting new studies and techniques developed
that aim to repair or restore osteochondral lesions and to treat
larger defects or the entire articular surface. The concept of a
biological total joint replacement appears to have much potential. Cite this article:
Pre-operative variables are increasingly being
used to determine eligibility for total knee replacement (TKR).
This study was undertaken to evaluate the relationships, interactions
and predictive capacity of variables available pre- and post-operatively
on patient satisfaction following TKR. Using nationally collected
patient reported outcome measures and data from the National Joint
Registry for England and Wales, we identified
22 798 patients who underwent TKR for osteoarthritis between August
2008 and September 2010. The ability of specific covariates to predict
satisfaction was assessed using ordinal logistic regression and
structural equational modelling. Only 4959 (22%) of 22 278 patients
rated the results of their TKR as ‘excellent’, despite the majority
(71%, n = 15 882) perceiving their knee symptoms to be much improved.
The strongest predictors of satisfaction were post-operative variables.
Satisfaction was significantly and positively related to the perception
of symptom improvement (operative success) and the post-operative
EuroQol-5D score. While also significant within the models pre-operative
variables were less important and had a minimal influence upon post-operative
satisfaction. The most robust predictions of satisfaction occurred
only when both pre- and post-operative variables were considered
together. These findings question the appropriateness of restricting
access to care based on arbitrary pre-operative thresholds as these
factors have little bearing on post-operative satisfaction. Cite this article:
Medial patellofemoral ligament (MPFL) reconstruction
is used to treat patellar instability and recurrent patellar dislocation.
Anatomical studies have found the MPFL to be a double-bundle structure.
We carried out a meta-analysis of studies reporting outcomes of
patellofemoral reconstruction using hamstring tendon autograft in
a double-bundle configuration and patellar fixation via mediolateral
patellar tunnels. A literature search was undertaken with no language restriction
in various databases from their year of inception to July 2012.
The primary outcome examined was the post-operative Kujala score.
We identified 320 MPFL reconstructions in nine relevant articles.
The combined mean post-operative Kujala score was 92.02 (standard
error ( Cite this article:
There is currently no consensus about the mean
volume of blood lost during spinal tumour surgery and surgery for metastatic
spinal disease. We conducted a systematic review of papers published
in the English language between 31 January 1992 and 31 January 2012.
Only papers that clearly presented blood loss data in spinal surgery
for metastatic disease were included. The random effects model was
used to obtain the pooled estimate of mean blood loss. We selected 18 papers, including six case series, ten retrospective
reviews and two prospective studies. Altogether, there were 760
patients who had undergone spinal tumour surgery and surgery for
metastatic spinal disease. The pooled estimate of peri-operative
blood loss was 2180 ml (95% confidence interval 1805 to 2554) with catastrophic
blood loss as high as 5000 ml, which is rare. Aside from two studies
that reported large amounts of mean blood loss (>
5500 ml), the
resulting funnel plot suggested an absence of publication bias.
This was confirmed by Egger’s test, which did not show any small-study
effects
(p = 0.119). However, there was strong evidence of heterogeneity
between studies (I2 = 90%; p <
0.001). Spinal surgery for metastatic disease is associated with significant
blood loss and the possibility of catastrophic blood loss. There
is a need to establish standardised methods of calculating and reporting
this blood loss. Analysis should include assessment by area of the
spine, primary pathology and nature of surgery so that the amount
of blood loss can be predicted. Consideration should be given to
autotransfusion in these patients. Cite this article:
The December 2012 Spine Roundup360 looks at: the Japanese neck disability index; adjacent segment degeneration; sacroiliac loads determined by limb length discrepancy; whether epidural steroids improve outcome in lumbar disc herniation; spondylodiscitis in infancy; total pedicle screws; and iliac crest autograft complications.
Mobile-bearing (MB) total knee replacement (TKR)
was introduced to reduce the risk of aseptic loosening and wear of
polyethylene inserts. However, no consistent clinical advantages
of mobile- over fixed-bearing (FB) TKR have been found. In this
study we evaluated whether mobile bearings have an advantage over
fixed bearings with regard to revision rates and clinical outcome
scores. Furthermore, we determined which modifying variables affected
the outcome. A systematic search of the literature was conducted to collect
clinical trials comparing MB and FB in primary TKR. The primary
outcomes were revision rates for any reason, aseptic loosening and
wear. Secondary outcomes included range of movement, Knee Society
score (KSS), Oxford knee score (OKS), Short-Form 12 (SF-12) score
and radiological parameters. Meta-regression techniques were used
to explore factors modifying the observed effect. Our search yielded 1827 publications, of which 41 studies met
our inclusion criteria, comprising over 6000 TKRs. Meta-analyses
showed no clinically relevant differences in terms of revision rates,
clinical outcome scores or patient-reported outcome measures between
MB and FB TKRs. It appears that theoretical assumptions of superiority
of MB over FB TKR are not borne out in clinical practice. Cite this article:
The survivorship of contemporary resurfacing arthroplasty of the hip using metal-on-metal bearings is better than that of first generation designs, but short-term failures still occur. The most common reasons for failure are fracture of the femoral neck, loosening of the component, osteonecrosis of the femoral head, reaction to metal debris and malpositioning of the component. In 2008 the Australian National Joint Registry reported an inverse relationship between the size of the head component and the risk of revision in resurfacing hip arthroplasty. Hips with a femoral component size of ≤ 44 mm have a fivefold increased risk of revision than those with femoral components of ≥ 55 mm irrespective of gender. We have reviewed the literature to explore this observation and to identify possible reasons including the design of the implant, loading of the femoral neck, the orientation of the component, the production of wear debris and the effects of metal ions, penetration of cement and vascularity of the femoral head. Our conclusion is that although multifactorial, the most important contributors to failure in resurfacing arthroplasty of the hip are likely to be the design and geometry of the component and the orientation of the acetabular component.
Deficiency of the abductor mechanism is a well-recognised
cause of pain and limping after total hip replacement (THR). This
can be found incidentally at the time of surgery, or it may arise
as a result of damage to the superior gluteal nerve intra-operatively,
or after surgery owing to mechanical failure of the abductor muscle
repair or its detachment from the greater trochanter. The incidence
of abductor failure has been reported as high as 20% in some studies.
The management of this condition remains a dilemma for the treating
surgeon. We review the current state of knowledge concerning post-THR
abductor deficiency, including the aetiology, diagnosis and management,
and the outcomes of surgery for this condition. Cite this article:
We investigated the incidence of and risk factors
for venous thromboembolism (VTE) following surgery of the shoulder
and elbow and assessed the role of thromboprophylaxis in upper limb
surgery. All papers describing VTE after shoulder and elbow surgery
published in the English language literature before 31 March 2012
were reviewed. A total of 14 papers were available for analysis,
most of which were retrospective studies and case series. The incidence
of VTE was 0.038% from 92 440 shoulder arthroscopic procedures,
0.52% from 42 261 shoulder replacements, and 0.64% from 4833 procedures
for fractures of the proximal humerus (open reduction and internal fixation
or hemiarthroplasty). The incidence following replacement of the
elbow was 0.26% from 2701 procedures. Diabetes mellitus, rheumatoid
arthritis and ischaemic heart disease were identified as the major
risk factors. The evidence that exists on thromboprophylaxis is based on level
III and IV studies, and we therefore cannot make any recommendations
on prophylaxis based on the current evidence. It seems reasonable
to adopt a multimodal approach that involves all patients receiving
mechanical prophylaxis, with chemical prophylaxis reserved for those
who are at high risk for VTE. Cite this article:
By and large, physicians and surgeons trust what they read, even if they take authors’ conclusions with a pinch of salt. There is a world of difference between being cautious about the implications of what you read and being defrauded by dishonest researchers. Fraud and scientific research are incompatible bedfellows and yet are an unhappy part of our research existence. All subspecialties are to blame and orthopaedics is no exception.
The October 2012 Research Roundup360 looks at: whether you can escape your genes; oral prophylaxis for DVT; non-responders and the internet; metal-on-metal, mice and damaged livers; sleeping on the job; cartilage contact stress in the normal human hip; and a perfect reason to subscribe to
We carried out a systematic review of the literature
to evaluate the evidence regarding the clinical results of the Ilizarov
method in the treatment of long bone defects of the lower limbs. Only 37 reports (three non-randomised comparative studies, one
prospective study and 33 case-series) met our inclusion criteria.
Although several studies were unsatisfactory in terms of statistical
heterogeneity, our analysis appears to show that the Ilizarov method
of distraction osteogenesis significantly reduced the risk of deep
infection in infected osseous lesions (risk ratio 0.14 (95% confidence
interval (CI) 0.10 to 0.20), p <
0.001). However, there was a
rate of re-fracture of 5% (95% CI 3 to 7), with a rate of neurovascular
complications of 2.2% (95% CI 0.3 to 4) and an amputation rate of
2.9% (95% CI 1.4 to 4.4).The data was generally not statistically
heterogeneous. Where tibial defects were >
8 cm, the risk of re-fracture
increased (odds ratio 3.7 (95% CI 1.1 to 12.5), p = 0.036). The technique is demanding for patients, illustrated by the voluntary
amputation rate of 1.6% (95% CI 0 to 3.1), which underlines the
need for careful patient selection. Cite this article:
Wrong-level surgery is a unique pitfall in spinal
surgery and is part of the wider field of wrong-site surgery. Wrong-site
surgery affects both patients and surgeons and has received much
media attention. We performed this systematic review to determine
the incidence and prevalence of wrong-level procedures in spinal
surgery and to identify effective prevention strategies. We retrieved
12 studies reporting the incidence or prevalence of wrong-site surgery
and that provided information about prevention strategies. Of these,
ten studies were performed on patients undergoing lumbar spine surgery
and two on patients undergoing lumbar, thoracic or cervical spine procedures.
A higher frequency of wrong-level surgery in lumbar procedures than
in cervical procedures was found. Only one study assessed preventative
strategies for wrong-site surgery, demonstrating that current site-verification protocols
did not prevent about one-third of the cases. The current literature
does not provide a definitive estimate of the occurrence of wrong-site
spinal surgery, and there is no published evidence to support the
effectiveness of site-verification protocols. Further prevention
strategies need to be developed to reduce the risk of wrong-site surgery.
Fractures of the femoral neck in children are
rare, high-energy injuries with high complication rates. Their treatment has
become more interventional but evidence of the efficacy of such
measures is limited. We performed a systematic review of studies
examining different types of treatment and their outcomes, including
avascular necrosis (AVN), nonunion, coxa vara, premature physeal
closure (PPC), and Ratliff’s clinical criteria. A total of 30 studies
were included, comprising 935 patients. Operative treatment and
open reduction were associated with higher rates of AVN. Delbet
types I and II fractures were most likely to undergo open reduction
and internal fixation. Coxa vara was reduced in the operative group,
whereas nonunion and PPC were not related to surgical intervention. Nonunion
and coxa vara were unaffected by the method of reduction. Capsular
decompression had no effect on AVN. Although surgery allows a more
anatomical union, it is uncertain whether operative treatment or
the type of reduction affects the rate of AVN, nonunion or PPC,
because more severe fractures were operated upon more frequently.
A delay in treatment beyond 24 hours was associated with a higher
incidence of AVN. Cite this article:
The August 2012 Shoulder &
Elbow Roundup360 looks at: platelet-rich fibrin matrix and the torn rotator cuff; ultrasound, trainees, and ducks out of water; the torn rotator cuff and conservative treatment; Bankart repair and subsequent degenerative change; proprioception after shoulder replacement; surgery for a terrible triad, with reasonable short-term results; and the WORC Index.
Using meta-analysis we compared the survival and clinical outcomes of cemented and uncemented techniques in primary total knee replacement. We reviewed randomised controlled trials and observational studies comparing cemented and uncemented fixation. Our primary outcome was survival of the implant free of aseptic loosening. Our secondary outcome was joint function as measured by the Knee Society score. We identified 15 studies that met our final eligibility criteria. The combined odds ratio for failure of the implant due to aseptic loosening for the uncemented group was 4.2 (95% confidence interval (CI) 2.7 to 6.5) (p <
0.0001). Subgroup analysis of data only from randomised controlled trials showed no differences between the groups for odds of aseptic loosening (odds ratio 1.9, 95% CI 0.55 to 6.40, p = 0.314). The weighted mean difference for the Knee Society score was 0.005 (95% CI −0.26 to 0.26) (p = 0.972). There was improved survival of the cemented compared to uncemented implants, with no statistically significant difference in the mean Knee Society score between groups for all pooled data.