Improvement of Orthopedic Residency Programs and Diversity: Dilemmas and Challenges, an International Perspective.

Background: To date, little has been published comparing the structure and requirements of orthopedic training programs across multiple countries. The goal of this study was to summarize and compare the characteristics of orthopedic training programs in the U.S.

Extra- vs. intramedullary treatment of pertrochanteric fractures: a biomechanical in vitro study comparing dynamic hip screw and intramedullary nail.

Introduction: Due to the demographic trend, pertrochanteric fractures of the femur will gain increasing importance in the future. Both extra- and intramedullary implants are used with good results in the treatment of these fractures. New, angular stable extramedullary implants promise increased postoperative stability even with unstable fractures.

Treatment of osteochondral fractures of the knee: a meta-analysis of available scientific evidence.

Purpose: Although traumatic osteochondral fractures of the knee represent a common pathology of the knee joint, there is no general agreement concerning specific treatment of this entity. This meta-analysis was initiated in order to evaluate scientific evidence on different treatment options for acute osteochondral fractures of the knee.

Methods: For this purpose an OVID-based systematic literature search was performed including the following databases: MEDLINE, MEDLINE preprints, Embase, CINAHL, Life Science Citations, British National Library of Health and Cochrane Central Register of Controlled Trials.

CaReS (MACT) versus microfracture in treating symptomatic patellofemoral cartilage defects: a retrospective matched-pair analysis.

Background: Treating patellofemoral articular cartilage lesions remains a challenging task in orthopedic surgery. Whereas microfracture and autologous chondrocyte implantation yield good results on femoral condyles, the therapeutic state of the art for treating patellofemoral lesions is yet to be determined. In this study, we compared the CaReS technique, which is a matrix-associated autologous chondrocyte implantation technique, to microfracture for treating patellofemoral articular cartilage lesions.

Bone marrow stromal cells in a liquid fibrin matrix improve the healing process of patellar tendon window defects.

Following injury, ligaments and tendons do not regain their normal biological and biomechanical status. This study analyzed whether an injection of human bone marrow stromal cells (BMSC) or human fibroblast in a liquid fibrin matrix influences the histological results, ultrastructural morphology, mRNA expression of essential extracellular matrix proteins, and material properties of the healing tissue. Standardized full-thickness, full-length defects of the central portion of patellar tendons were created in 96 immunodeficient rats, and filled with human BMSC in a fibrin matrix (BMSC group), human fibroblasts in a fibrin matrix (fibroblast group), or fibrin matrix only (matrix group), or left untreated (defect group).

Tissue engineering of osteochondral constructs in vitro using bioreactors.

Articular cartilage is a relatively simple tissue, but has a limited capacity of restoration. Tissue engineering is a promising field that seeks to accomplish the in vitro generation of complex, functional, 3-dimensional tissues. Various cell types and scaffolds have been tested for these purposes.

Influence of fibrin glue on proliferation and differentiation of human bone marrow stromal cells seeded on a biologic 3-dimensional matrix.

For tissue engineering of bone, a carrier matrix and efficient cell seeding are desirable. This study analysed the effect of fibrin glue on bone marrow stromal cells (BMSC) adhesion, proliferation (MTS-Test), differentiation (alkaline phosphatase (AP), osteocalcin (OC), ELISA) and compared the results with cells seeded within culture media on a decellularized, xenogenic bone matrix. There was no significant difference regarding cell adhesion.

A system for engineering an osteochondral construct in the shape of an articular surface: preliminary results.

A tissue-engineered articular condyle could provide a new alternative approach to joint replacement. This study describes progress made towards engineering an articular condyle in vitro using human bone marrow stromal cells (hBMSCs) in a biphasic matrix. hBMSCs were transferred to a rat collagen-I hydrogel which was then pressed onto a bovine cancellous bone matrix.

No mid-term difference in mosaicplasty in previously treated versus previously untreated patients with osteochondral lesions of the talus.

Introduction: Osteochondral transplantations, albeit technically challenging, appear promising not only in knee joint lesions, but also in the treatment of talus lesions. We hypothesized that in patients suffering osteochondral lesions of the talus, favorable outcomes are obtained in patients undergoing primary mosaicplasty as compared to patients undergoing secondary mosaicplasty.

Materials And Methods: Over a 3-year period (1998-2001), 14 patients (six male, eight female, median age 22 years) were treated with an autologous osteochondral transplantation of the talus.

Tissue engineering of tendons and ligaments by human bone marrow stromal cells in a liquid fibrin matrix in immunodeficient rats: results of a histologic study.

Introduction: The original complex structure and mechanical properties are not fully restored after ligament and tendon injuries. Due to their high proliferation rate and differentiation potential, Bone Marrow Stromal Cells (BMSC) are considered to be an ideal cell source for tissue engineering to optimize the healing process. Ideal matrices for tissue engineering of ligaments and tendons should allow for homogenous cell seeding and offer sufficient stability.

Eccentric training decreases paratendon capillary blood flow and preserves paratendon oxygen saturation in chronic achilles tendinopathy.

Study Design: A controlled, randomized, prospective study,

Objective: To assess the changes in paratendon microcirculation after 12 weeks of daily painful eccentric training in individuals with chronic Achilles tendinopathy.

Background: Changes in tendon and paratendon microcirculation are evident in insertional and midportion Achilles tendinopathy. Whether the paratendon is involved in eccentric training response is not known.

[Open reduction and internal fixation by primary subtalar arthrodesis for intraarticular calcaneal fractures].

Objective: To prevent the development of painful posttraumatic degenerative joint disease by a primary one-stage procedure to treat calcaneal fractures involving obvious comminution or severe and extensive cartilage damage to the subtalar facet.

Indications: Sanders type IV calcaneal fractures with severe and extensive cartilage destruction. The definitive indication for arthrodesis can only be established intraoperatively.

Arthroscopic partial meniscectomy.

Objective: Excision of damaged meniscal tissue whereby the mechanical obstacles to joint movement are eliminated. As much functional, intact meniscal tissue should be retained as possible. Resection of only the bare minimum.

Changes of Achilles midportion tendon microcirculation after repetitive simultaneous cryotherapy and compression using a Cryo/Cuff.

Background: Cryotherapy and compression have been shown to decrease pain and improve function. The dosage and timing of these options remain unclear.

Purpose: To examine the effects of a standardized compression and cryotherapy device (Cryo/Cuff) on midportion Achilles tendon microcirculation during intermittent administration.

Rapid rehabilitation programme following sacral stress fracture in a long-distance running female athlete.

Stress fractures occur in normal bone due to mechanical overload by cyclic stress increasing the osteoclastic activity, thus facilitating weakening leading to fracture of bones. Long-distance running may lead to stress fractures of the mid- and distal tibia and of the metatarsal bones. Stress fractures to the sacrum are rare.

Recurrent shoulder instability among athletes: changes in quality of life, sports activity, and muscle function following open repair.

Background: Recurrent anterior shoulder instability is a disabling condition in young athletes with possibly underestimated impact on quality of life and sports activity. Commonly used clinical scoring systems do not reflect the impairment of quality of life and sports activity. It was our aim to assess the return to preinjury levels of quality of life and sports activity as well as the changes in muscle function among competitive and recreational athletes.

Hinged external fixation and closed reduction for distal humerus fracture.

Elbow fractures are relatively rare in extremity injuries. Functional deficits often comprise the outcome. We report of a 77-year-old diabetic lady with a distal humerus fracture.

Achilles tendon and paratendon microcirculation in midportion and insertional tendinopathy in athletes.

Background: Neovascularisation can be detected qualitatively by Power Doppler in Achilles tendinopathy. Quantitative data regarding tendon microcirculation have not been established and may be substantial.

Purpose: To assess the microcirculation of the Achilles tendon and the paratendon in healthy volunteers as well as in athletes with either midportion or insertional tendinopathy.

Modulation of proliferation and differentiation of human bone marrow stromal cells by fibroblast growth factor 2: potential implications for tissue engineering of tendons and ligaments.

Bone marrow stromal cells (BMSCs) play a central role in the repair and regeneration of mesenchymal tissues. For tissue engineering of ligaments and tendons, both stimulation of cell proliferation and differentiation with increased expression of essential extracellular matrix proteins and cytoskeletal elements are desirable. This study analyzes the effect of low-dose (3 ng/mL) fibroblast growth factor 2 (FGF-2) and high-dose FGF-2 (30 ng/mL) on proliferation (bromodeoxyuridine content, spectrophotometry), differentiation (transcription of collagen I, collagen III, fibronectin, elastin, alpha-smooth muscle actin, and vimentin, reverse transcription-polymerase chain reaction, and cell density and apoptosis (annexin V, fluorescence-activated cell sorting) of human BMSCs, and compares the results with those of a control group without FGF-2.

Alpha-smooth muscle actin containing contractile fibroblastic cells in human knee arthrofibrosis tissue. Winner of the AGA-DonJoy Award 2003.

Introduction: Primary arthrofibrosis is of major concern after joint trauma or knee ligament surgery. The underlying mechanism in detail remains unclear. Highly differentiated fibroblastic cells, so-called myofibroblasts, express the actin isoform alpha-smooth muscle actin (ASMA) and have been found to play a major role in tissue contraction during wound healing and organ fibrosis.

Modulation of cell functions of human tendon fibroblasts by different repetitive cyclic mechanical stress patterns.

Mechanical stress is a factor that is thought to play an essential role in tissue generation and reparation processes. The aim of the present study was to investigate the influence of different repetitive cyclic longitudinal stress patterns on proliferation, apoptosis and expression of heat shock protein (HSP) 72. To perform this study, human tendon fibroblasts were seeded on flexible silicone dishes.

Cyclic mechanical strain induces NO production in human patellar tendon fibroblasts--a possible role for remodelling and pathological transformation.

The mechanism by which tendon fibroblasts can detect strain forces and respond to them is fairly unknown. Nitric oxide (NO) is a messenger molecule that among others can respond to shear stress in endothelial cells. Therefore, it was investigated whether cyclic mechanical strain induces NO in vitro in human patellar tendon fibroblasts.