Minimally invasive fasciotomy using a lighted retractor in the treatment of chronic exertional compartment syndrome.

Chronic exertional compartment syndrome can be a debilitating cause of lower leg pain that typically affects young, healthy people during a variety of aerobic activities. Conservative management has produced a poor success rate and numerous techniques for surgical decompression have been described. Many of these, however, involve blind fascial dissection which increases the risk of direct nerve injury or insufficient fascial release.

Outcome of total hip and knee arthroplasty in HIV-infected patients: A systematic review.

Significant advances in the treatment of Human Immunodeficiency Virus (HIV) have occurred in recent times, with life expectancy now approaching the normal population. Therefore, patients with HIV will increasingly be undergoing joint replacement in the future, however concerns remain regarding the complications and outcome in this patient cohort. The aim was to assess the outcome of total hip and knee arthroplasty in HIV-infected patients.

Molecular Mechanism of Ischaemic Preconditioning of Skeletal Muscle In Vitro.

Introduction Ischaemic preconditioning (IPC) is a phenomenon whereby tissues develop an increased tolerance to ischaemia and subsequent reperfusion if first subjected to sublethal periods of ischaemia. Despite extensive investigation of IPC, the molecular mechanism remains largely unknown. Our aim was to show genetic changes that occur in skeletal muscle cells in response to IPC.

Engineering Tissues That Mimic the Zonal Nature of Articular Cartilage Using Decellularized Cartilage Explants Seeded with Adult Stem Cells.

Articular cartilage (AC) possesses uniquely complex mechanical properties; for example its stiffness increases with depth through the tissue and it softens when compressed. These properties are integral to the function of AC and can be attributed to the tissue's collagen network and how it interacts with negatively charged proteoglycans. In this study, scaffolds containing arrays of channels were produced from decellularized AC explants derived from skeletally immature and mature pigs.

Biofabrication of soft tissue templates for engineering the bone-ligament interface.

Regenerating damaged tissue interfaces remains a significant clinical challenge, requiring recapitulation of the structure, composition, and function of the native enthesis. In the ligament-to-bone interface, this region transitions from ligament to fibrocartilage, to calcified cartilage and then to bone. This gradation in tissue types facilitates the transfer of load between soft and hard structures while minimizing stress concentrations at the interface.

Porous Scaffolds Derived from Devitalized Tissue Engineered Cartilaginous Matrix Support Chondrogenesis of Adult Stem Cells.

ECM-derived scaffolds have previously been developed from devitalized native cartilage and successfully used in tissue engineering. Such ECM-based biomaterials are commonly derived from animal tissue, which may not represent the ideal source for applications in human. Native human ECM can be used as an alternative to xenogeneic tissue; however, its supply may be limited, leading to the need for a more readily available source of such biomaterials.

Stem cells display a donor dependent response to escalating levels of growth factor release from extracellular matrix-derived scaffolds.

Numerous growth factor delivery systems have been developed for tissue engineering. However, little is known about how the dose of a specific protein will influence tissue regeneration, or how different patients will respond to altered levels of growth factor presentation. The objective of the present study was to assess stem cell chondrogenesis within extracellular-matrix (ECM)-derived scaffolds loaded with escalating levels of transforming growth factor (TGF)-β3.

Judgments of Nonverbal Behaviour by Children with High-Functioning Autism Spectrum Disorder: Can they Detect Signs of Winning and Losing from Brief Video Clips?

Typically developing children are able to judge who is winning or losing from very short clips of video footage of behaviour between active match play across a number of sports. Inferences from "thin slices" (short video clips) allow participants to make complex judgments about the meaning of posture, gesture and body language. This study extends the use of the thin slice research paradigm to children with high-functioning autism spectrum disorder (ASD).

Bilateral total hip replacement in arthrogryposis multiplex congenita.

The authors present a case of bilateral total hip replacements (THRs) in a 56-year-old patient with arthrogryposis multiplex congenita (AMC). The considerations for the perioperative period and the outcome are discussed. Preoperative planning included an anaesthetic review and availability of fiberoptic intubation due to poor mouth opening.

Decellularization of porcine articular cartilage explants and their subsequent repopulation with human chondroprogenitor cells.

Engineering tissues with comparable structure, composition and mechanical functionality to native articular cartilage remains a challenge. One possible solution would be to decellularize xenogeneic articular cartilage in such a way that the structure of the tissue is maintained, and to then repopulate this decellularized matrix with human chondroprogenitor cells that will facilitate the reconstitution, maintenance and eventual turnover of the construct following implantation. The overall objective of this study was to develop a protocol to efficiently decellularize porcine articular cartilage grafts and to identify a methodology to subsequently repopulate such explants with human chondroprogenitor cells.

A Long-term Retrospective Evaluation of Functional and Radiographic Outcomes of Pediatric Hip Surgery in Hurler Syndrome.

Background: After successful hematopoietic stem cell transplantation, maintaining function and mobility have become key goals in the management of patients with Hurler syndrome, (mucopolysaccharoidosis type 1H). The aim of this study was to establish the functional and radiologic outcomes after hip surgery in patients with this condition who had reached skeletal maturity.

Methods: We prospectively followed 13 mucopolysaccharoidosis type 1H patients with closed triradiate cartilages who had undergone hip surgery in a single institution (Our Lady's Children's Hospital, Crumlin) in early childhood, after successful hematopoietic stem cell transplantation.

Comparison of four chondral repair techniques in the hip joint: a biomechanical study using a physiological human cadaveric model.

Objective: The objective of this study was to assess the biomechanical stability of three types of chondral flap repair techniques as well as a hydrogel scaffold implantation on the acetabular articular surface using a physiological human cadaveric model.

Methods: Chondral flaps were created in the antero-superior zone of the acetabulum in a series of human cadaveric hip joints. The chondral flap was repaired by fibrin glue, cyanoacrylate, suture technique and an agarose hydrogel scaffold sealed with fibrin glue using six hips in each case.

On the fate of particles liberated from hydroxyapatite coatings in vivo.

Purpose: Hydroxyapatite (HA) has been used as a coating for orthopaedic implants for over 30 years to help promote the fixation of orthopaedic implants into the surrounding bone. However, concerns exist about the fate of the hydroxyapatite coating and hydroxyapatite particles in vivo, especially in the wake of recent concerns about particulates from metal-on-metal bearings.

Methods: Here, we assess the mechanisms of particle detachment from coated orthopaedic devices as well as the safety and performance concerns and biomedical implications arising from the liberation of the particles by review of the literature.

Infrapatellar fat pad-derived stem cells maintain their chondrogenic capacity in disease and can be used to engineer cartilaginous grafts of clinically relevant dimensions.

A therapy for regenerating large cartilaginous lesions within the articular surface of osteoarthritic joints remains elusive. While tissue engineering strategies such as matrix-assisted autologous chondrocyte implantation can be used in the repair of focal cartilage defects, extending such approaches to the treatment of osteoarthritis will require a number of scientific and technical challenges to be overcome. These include the identification of an abundant source of chondroprogenitor cells that maintain their chondrogenic capacity in disease, as well as the development of novel approaches to engineer scalable cartilaginous grafts that could be used to resurface large areas of damaged joints.

Atypical stress-avulsion fracture of the Lisfranc joint complex.

Antiphospholipid syndrome and systemic erythematosus have been associated with metatarsal stress fractures. Stress fractures of the Lisfranc joint complex are uncommon injuries but have been reported to occur most frequently in ballet dancers. We present a case of an avulsion fracture of the Lisfranc joint complex that occurred spontaneously.

A mountain among molehills: removing an impinging large femoral neck osteochondroma in a man with hereditary multiple exostoses.

A 31-year-old man with a history of hereditary multiple exostoses (HME) presented with persistent right groin pain and reduced hip range of movement. Examination demonstrated a positive FADIR (flexion, adduction and internal rotation) test suggesting femoroacetabular impingement (FAI). Investigations showed multiple sessile osteochondromata of the right femur with a dominant anterolateral femoral neck osteochondroma causing flexion block.

Combining BMP-6, TGF-β3 and hydrostatic pressure stimulation enhances the functional development of cartilage tissues engineered using human infrapatellar fat pad derived stem cells.

The objective of this study was to identify a combination of growth factors that could be used with hydrostatic pressure (HP) stimulation to enhance the functional development of cartilaginous grafts engineered using human infrapatellar fat pad derived stem cells (FPSCs) isolated from osteoarthritic patients. Agarose hydrogels were first seeded with FPSCs at different seeding densities and maintained in a chondrogenic media supplemented with TGF-β3. It was found that chondrogenesis of human FPSCs in hydrogel culture is dependent on the cell seeding density (10 versus 30 million cells per ml), with greater sulphated glycosaminoglycan (sGAG) and collagen synthesis (normalised to DNA content) observed at higher seeding densities.

Osteoporotic hip fractures: the burden of fixation failure.

Osteoporotic hip fractures are a major cause of morbidity and mortality in the elderly. Furthermore, reduced implant anchorage in osteoporotic bone predisposes towards fixation failure and with an ageing population, even low failure rates represent a significant challenge to healthcare systems. Fixation failure in fragility fractures of the hip ranges from 5% in peritrochanteric fractures through to 15% and 41% in undisplaced and displaced fractures of the femoral neck, respectively.

Total joint arthroplasty in nonagenarians--a retrospective review of complications and resource use.

Increased age brings with it the potential for increased surgical risk. Assessment of specific age cohorts is necessary to plan future service provision and this is the case in hip and knee arthroplasty as the demand for these procedures is anticipated to increase. We retrospectively reviewed the outcomes, including complications, length of stay and blood transfusion rate, in a cohort of 35 nonagenarians undergoing primary or revision total hip and knee arthroplasty.