The aim of this study was to examine whether asymmetric loading
influences macrophage elastase (MMP12) expression in different parts
of a rat tail intervertebral disc and growth plate and if MMP12
expression is correlated with the severity of the deformity. A wedge deformity between the ninth and tenth tail vertebrae
was produced with an Ilizarov-type mini external fixator in 45 female
Wistar rats, matched for their age and weight. Three groups were
created according to the degree of deformity (10°, 30° and 50°).
A total of 30 discs and vertebrae were evaluated immunohistochemically
for immunolocalisation of MMP12 expression, and 15 discs were analysed
by western blot and zymography in order to detect pro- and active
MMP12.Objectives
Methods
This review briefly summarises some of the definitive
studies of articular cartilage by microscopic MRI (µMRI) that were
conducted with the highest spatial resolutions. The article has
four major sections. The first section introduces the cartilage
tissue, MRI and µMRI, and the concept of image contrast in MRI.
The second section describes the characteristic profiles of three
relaxation times (T1, T2 and T1ρ)
and self-diffusion in healthy articular cartilage. The third section
discusses several factors that can influence the visualisation of
articular cartilage and the detection of cartilage lesion by MRI
and µMRI. These factors include image resolution, image analysis
strategies, visualisation of the total tissue, topographical variations
of the tissue properties, surface fibril ambiguity, deformation
of the articular cartilage, and cartilage lesion. The final section
justifies the values of multidisciplinary imaging that correlates
MRI with other technical modalities, such as optical imaging. Rather
than an exhaustive review to capture all activities in the literature,
the studies cited in this review are merely illustrative.
To elucidate the effects of age on the expression levels of the receptor activator of the nuclear factor-κB ligand (RANKL) and osteoclasts in the periodontal ligament during orthodontic mechanical loading and post-orthodontic retention. The study included 20 male Sprague-Dawley rats, ten in the young group (aged four to five weeks) and ten in the adult group (aged 18 to 20 weeks). In each rat, the upper-left first molar was subjected to a seven-day orthodontic force loading followed by a seven-day retention period. The upper-right first molar served as a control. The amount of orthodontic tooth movement was measured after seven-day force application and seven-day post-orthodontic retention. The expression levels of RANKL and the tartrate-resistant acid phosphatase (TRAP)-positive osteoclasts were evaluated on day 7 (end of mechanical force loading) and day 14 (after seven days of post-orthodontic retention). Statistical analysis was performed using the Objectives
Materials and Methods
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:
Mesenchymal stem-cell based therapies have been
proposed as novel treatments for intervertebral disc degeneration,
a prevalent and disabling condition associated with back pain. The
development of these treatment strategies, however, has been hindered
by the incomplete understanding of the human nucleus pulposus phenotype
and by an inaccurate interpretation and translation of animal to
human research. This review summarises recent work characterising
the nucleus pulposus phenotype in different animal models and in
humans and integrates their findings with the anatomical and physiological
differences between these species. Understanding this phenotype
is paramount to guarantee that implanted cells restore the native
functions of the intervertebral disc. Cite this article:
The pathogenesis of rotator cuff disease (RCD) is complex and
not fully understood. This systematic review set out to summarise
the histological and molecular changes that occur throughout the
spectrum of RCD. We conducted a systematic review of the scientific literature
with specific inclusion and exclusion criteria.Introduction
Methods
To investigate the appropriate dose and interval for the administration
of triamcinolone acetonide (TA) in treating tendinopathy to avoid
adverse effects such as tendon degeneration and rupture. Human rotator cuff-derived cells were cultured using three media:
regular medium (control), regular medium with 0.1 mg/mL of TA (low
TA group), and with 1.0 mg/mL of TA (high TA group). The cell morphology,
apoptosis, and viability were assessed at designated time points.Objectives
Methods
We report the outcome of 84 nonunions involving
long bones which were treated with rhBMP-7, in 84 patients (60 men:
24 women) with a mean age 46 years (18 to 81) between 2003 and 2011.
The patients had undergone a mean of three previous operations (one
to 11) for nonunion which had been present for a mean of 17 months
(4 months to 20 years). The nonunions involved the lower limb in
71 patients and the remainder involved the upper limb. A total of 30
nonunions were septic. Treatment was considered successful when
the nonunion healed without additional procedures. The relationship
between successful union and the time to union was investigated
and various factors including age and gender, the nature of the
nonunion (location, size, type, chronicity, previous procedures,
infection, the condition of the soft tissues) and type of index
procedure (revision of fixation, type of graft, amount of rhBMP-7) were
analysed. The improvement of the patients’ quality of life was estimated
using the Short Form (SF) 12 score. A total of 68 nonunions (80.9%) healed with no need for further
procedures at a mean of 5.4 months (3 to 10) post-operatively. Multivariate
logistic regression analysis of the factors affecting union suggested
that only infection significantly affected the rate of union
(p = 0.004).Time to union was only affected by the number of previous
failed procedures
(p = 0.006). An improvement of 79% and 32.2% in SF-12 physical and
mental score, respectively, was noted within the first post-operative
year. Rh-BMP-7 combined with bone grafts, enabled healing of the nonunion
and improved quality of life in about 80% of patients. Aseptic nonunions
were much more likely to unite than septic ones. The number of previous
failed operations significantly delayed the time to union. Cite this article:
We reviewed 59 bone graft substitutes marketed
by 17 companies currently available for implantation in the United Kingdom,
with the aim of assessing the peer-reviewed literature to facilitate
informed decision-making regarding their use in clinical practice.
After critical analysis of the literature, only 22 products (37%)
had any clinical data. Norian SRS (Synthes), Vitoss (Orthovita),
Cortoss (Orthovita) and Alpha-BSM (Etex) had Level I evidence. We question
the need for so many different products, especially with limited
published clinical evidence for their efficacy, and conclude that
there is a considerable need for further prospective randomised
trials to facilitate informed decision-making with regard to the
use of current and future bone graft substitutes in clinical practice. Cite this article:
Injectable Bromelain Solution (IBS) is a modified investigational derivate of the medical grade bromelain-debriding pharmaceutical agent (NexoBrid) studied and approved for a rapid (four-hour single application), eschar-specific, deep burn debridement. We conducted an Specially prepared medical grade IBS was injected into fresh Dupuytren’s cords excised from patients undergoing surgical fasciectomy. These cords were tested by tension-loading them to failure with the Zwick 1445 (Zwick GmbH & Co. KG, Ulm, Germany) tension testing system.Objectives
Materials and Methods
The purpose of this study was to clarify the appearance of the reparative tissue on the articular surface and to analyse the properties of the reparative tissue after hemicallotasis osteotomy (HCO) using MRI T1ρ and T2 mapping. Coronal T1ρ and T2 mapping and three-dimensional gradient-echo images were obtained from 20 subjects with medial knee osteoarthritis. We set the regions of interest (ROIs) on the full-thickness cartilage of the medial femoral condyle (MFC) and medial tibial plateau (MTP) of the knee and measured the cartilage thickness (mm) and T1ρ and T2 relaxation times (ms). Statistical analysis of time-dependent changes in the cartilage thickness and the T1ρ and T2 relaxation times was performed using one-way analysis of variance, and Scheffe’s test was employed for Objectives
Methods
The objective of this study was to determine if the use of fascia lata as a tendon regeneration guide (placed into the tendon canal following harvesting the semitendinosus tendon) would improve the incidence of tissue regeneration and prevent fatty degeneration of the semitendinosus muscle. Bilateral semitendinosus tendons were harvested from rabbits using a tendon stripper. On the inducing graft (IG) side, the tendon canal and semitendinosus tibial attachment site were connected by the fascia lata, which was harvested at the same width as the semitendinosus tendon. On the control side, no special procedures were performed. Two groups of six rabbits were killed at post-operative weeks 4 and 8, respectively. In addition, three healthy rabbits were killed to obtain normal tissue. We evaluated the incidence of tendon tissue regeneration, cross-sectional area of the regenerated tendon tissue and proportion of fatty tissue in the semitendinosus muscle.Objectives
Materials and Methods
This multicentre prospective clinical trial aimed
to determine whether early administration of alendronate (ALN) delays
fracture healing after surgical treatment of fractures of the distal
radius. The study population comprised 80 patients (four men and
76 women) with a mean age of 70 years (52 to 86) with acute fragility
fractures of the distal radius requiring open reduction and internal
fixation with a volar locking plate and screws. Two groups of 40 patients
each were randomly allocated either to receive once weekly oral
ALN administration (35 mg) within a few days after surgery and continued
for six months, or oral ALN administration delayed until four months
after surgery. Postero-anterior and lateral radiographs of the affected
wrist were taken monthly for six months after surgery. No differences
between groups was observed with regard to gender (p = 1.0), age
(p = 0.916), fracture classification (p = 0.274) or bone mineral
density measured at the spine (p = 0.714). The radiographs were
assessed by three independent assessors. There were no significant
differences in the mean time to complete cortical bridging observed
between the ALN group (3.5 months ( Cite this article:
The December 2013 Research Roundup360 looks at: Inflammation implicated in FAI; Ponseti and effective teaching; Unicompartmental knee design and tibial strain; Bisphosphonates and fracture healing; Antibiosis in cement; Zoledronic acid improves primary stability in revision?; Osteoporotic fractures revisited; and electroarthrography for monitoring of cartilage degeneration
Salubrinal is a synthetic agent that elevates phosphorylation
of eukaryotic translation initiation factor 2 alpha (eIF2α) and
alleviates stress to the endoplasmic reticulum. Previously, we reported
that in chondrocytes, Salubrinal attenuates expression and activity
of matrix metalloproteinase 13 (MMP13) through downregulating nuclear
factor kappa B (NFκB) signalling. We herein examine whether Salubrinal
prevents the degradation of articular cartilage in a mouse model
of osteoarthritis (OA). OA was surgically induced in the left knee of female mice. Animal
groups included age-matched sham control, OA placebo, and OA treated
with Salubrinal or Guanabenz. Three weeks after the induction of
OA, immunoblotting was performed for NFκB p65 and p-NFκB p65. At
three and six weeks, the femora and tibiae were isolated and the sagittal
sections were stained with Safranin O.Objectives
Methods
Rotator cuff tears are among the most common and debilitating
upper extremity injuries. Chronic cuff tears result in atrophy and
an infiltration of fat into the muscle, a condition commonly referred
to as ‘fatty degeneration’. While stem cell therapies hold promise
for the treatment of cuff tears, a suitable immunodeficient animal
model that could be used to study human or other xenograft-based
therapies for the treatment of rotator cuff injuries had not previously
been identified. A full-thickness, massive supraspinatus and infraspinatus tear
was induced in adult T-cell deficient rats. We hypothesised that,
compared with controls, 28 days after inducing a tear we would observe
a decrease in muscle force production, an accumulation of type IIB
fibres, and an upregulation in the expression of genes involved
with muscle atrophy, fibrosis and inflammation.Objectives
Methods
Pathological assessment of periprosthetic tissues is important, not only for diagnosis, but also for understanding the pathobiology of implant failure. The host response to wear particle deposition in periprosthetic tissues is characterised by cell and tissue injury, and a reparative and inflammatory response in which there is an innate and adaptive immune response to the material components of implant wear. Physical and chemical characteristics of implant wear influence the nature of the response in periprosthetic tissues and account for the development of particular complications that lead to implant failure, such as osteolysis which leads to aseptic loosening, and soft-tissue necrosis/inflammation, which can result in pseudotumour formation. The innate response involves phagocytosis of implant-derived wear particles by macrophages; this is determined by pattern recognition receptors and results in expression of cytokines, chemokines and growth factors promoting inflammation and osteoclastogenesis; phagocytosed particles can also be cytotoxic and cause cell and tissue necrosis. The adaptive immune response to wear debris is characterised by the presence of lymphoid cells and most likely occurs as a result of a cell-mediated hypersensitivity reaction to cell and tissue components altered by interaction with the material components of particulate wear, particularly metal ions released from cobalt-chrome wear particles. Cite this article: Professor N. A. Athanasou. The pathobiology and pathology of aseptic implant failure.
The December 2014 Foot &
Ankle Roundup360 looks at: Charcot feet, biomarkers and diabetes; weight bearing following Achilles tendon rupture; endobuttons and mal-reduced diastasis; evidence for stem cell therapies in osteochondral lesions of the talus; syndesmosis fixation in SER ankle fractures; and self-reporting for foot and ankle outcomes.
The treatment of osteochondral lesions is of
great interest to orthopaedic surgeons because most lesions do not heal
spontaneously. We present the short-term clinical outcome and MRI
findings of a cell-free scaffold used for the treatment of these
lesions in the knee. A total of 38 patients were prospectively evaluated
clinically for two years following treatment with an osteochondral
nanostructured biomimetic scaffold. There were 23 men and 15 women; the
mean age of the patients was 30.5 years (15 to 64). Clinical outcome
was assessed using the Knee Injury and Osteoarthritis Outcome Score
(KOOS), the Tegner activity scale and a Visual Analgue scale for
pain. MRI data were analysed based on the Magnetic Resonance Observation
of Cartilage Repair Tissue (MOCART) scoring system at three, 12
and 24 months post-operatively. There was a continuous significant
clinical improvement after surgery. In two patients, the scaffold
treatment failed (5.3%) There was a statistically significant improvement
in the MOCART precentage scores. The repair tissue filled most of
the defect sufficiently. We found subchondral laminar changes in all
patients. Intralesional osteophytes were found in two patients (5.3%).
We conclude that this one-step scaffold-based technique can be used
for osteochondral repair. The surgical technique is straightforward,
and the clinical results are promising. The MRI aspects of the repair
tissue continue to evolve during the first two years after surgery.
However, the subchondral laminar and bone changes are a concern. Cite this article:
