Effects of fondaparinux on wound drainage after total hip and knee arthroplasty.

Background: The purpose of this investigation was to determine the effects of fondaparinux on postoperative wound drainage, length of hospital stay (LOS) and rate of surgical site infection in total joint patients.

Methods: 117 patients undergoing total joint arthroplasty treated with fondaparinux for venous thromboembolism (VTE) prophylaxis were prospectively studied.

Results: The average time to a dry wound was 3.

Calculating the Position of the Joint Line of the Knee Using Anatomical Landmarks.

Restoration of the joint line of the knee during primary and revision total knee arthroplasty is a step that directly influences patient outcomes. In revision total knee arthroplasty, necessary bony landmarks may be missing or obscured, so there remains a lack of consensus on how to accurately identify and restore the joint line of the knee. In this study, 50 magnetic resonance images of normal knees were analyzed to determine a quantitative relationship between the joint line of the knee and 6 bony landmarks: medial and lateral femoral epicondyles, medial and lateral femoral metaphyseal flares, tibial tubercle, and proximal tibio-fibular joint.

Anemia versus transfusion: does blood conservation increase the risk of complications?

Orthopedic trauma patients are routinely transfused for anemia even when asymptomatic at rest, despite there being relatively little scientific evidence as to what level of anemia can be safely tolerated. Some surgeons prefer a more liberal approach, transfusing to keep hemoglobin (Hgb) levels at 7.0 g/dL or higher; others prefer a more conservative approach, allowing Hgb levels to drop below 7.

Effect of day of the week of primary total hip arthroplasty on length of stay at a university-based teaching medical center.

Length of hospital stay (LHS) after primary total hip arthroplasty (THA) constitutes a critical outcome measure, as prolonged LHS implies increased resource expenditure. Investigations have highlighted factors that affect LHS after THA. These factors include advanced age, medical comorbidities, obesity, intraoperative time, anesthesia technique, surgical site infection, and incision length.

Cartilage oligomeric matrix protein and its binding partners in the cartilage extracellular matrix: interaction, regulation and role in chondrogenesis.

Thrombospondins (TSPs) are widely known as a family of five calcium-binding matricellular proteins. While these proteins belong to the same family, they are encoded by different genes, regulate different cellular functions and are localized to specific regions of the body. TSP-5 or Cartilage Oligomeric Matrix Protein (COMP) is the only TSP that has been associated with skeletal disorders in humans, including pseudoachondroplasia (PSACH) and multiple epiphyseal dysplasia (MED).

Failure of a constrained acetabular liner without reinforcement ring disruption.

Several risk factors for dislocation after total hip arthroplasty (THA) have been identified including operative-, patient-, and implant-related factors. The following case report describes the dislocation of a revision THA without disruption of the constrained liner or containment ring. The possible mechanisms leading to this type of failure include lever-out impingement and poor abductor function, or tension secondary to prior surgery.

Subtrochanteric Fracture following Removal of a Porous Tantalum Implant.

Osteonecrosis of the hip accounts for about 10% of all total hip arthroplasty cases and presents a significant challenge for those patients with and without femoral head collapse. Subtrochanteric femur fractures have been reported with numerous types of proximal femoral implants. Care must be taken to avoid penetrating the lateral cortex of the proximal femur inferior to the distal border of the lesser trochanter.

The Oncogene LRF Stimulates Proliferation of Mesenchymal Stem Cells and Inhibits Their Chondrogenic Differentiation.

Objective: The oncogene leukemia/lymphoma-related factor (LRF) enhances chondrosarcoma proliferation and malignancy. This study aimed to investigate the roles of LRF in chondrogenic differentiation of primary human bone marrow-derived mesenchymal stem cells (BMSCs).

Design: LRF was overexpressed in BMSC by lentiviral transduction.

The pros and cons of using larger femoral heads in total hip arthroplasty.

With the introduction of improved bearing surfaces for total hip arthroplasty (THA) has come a reintroduction of larger femoral heads with the promise of reducing the rate of hip instability and increasing hip range of motion (ROM). The size of femoral heads used for THA ranges from 22 to 40 mm, and even larger heads are used for hip resurfacing. With accurately positioned components, larger heads reduce the hip instability rate and theoretically increase hip ROM.

Identification of the landmark registration safe zones during total knee arthroplasty using an imageless navigation system.

Incorrect registration during computer assisted total knee arthroplasty (CA-TKA) leads to malposition of implants. Our aim was to evaluate the tolerable error in anatomic landmark registration. We incorrectly registered the femoral epicondyles, femoral and tibial centers, as well as the malleoli and documented the change in angulation or rotation.

c-Maf Transcription Factor Regulates ADAMTS-12 Expression in Human Chondrogenic Cells.

Objective: ADAMTS (a disintegrin and metalloproteinase with thrombospondin type-1 motif) zinc metalloproteinases are important during the synthesis and breakdown of cartilage extracellular matrix. ADAMTS-12 is up-regulated during in vitro chondrogenesis and embryonic limb development; however, the regulation of ADAMTS-12 expression in cartilage remains unknown. The transcription factor c-Maf is a member of Maf family of basic ZIP (bZIP) transcription factors.

Cartilage oligomeric matrix protein enhances osteogenesis by directly binding and activating bone morphogenetic protein-2.

Bone morphogenetic proteins (BMPs) are effective for bone regeneration, and are used clinically. However, supraphysiological doses are required, which limits their use. Cartilage oligomeric matrix protein is an extracellular matrix protein, which we have previously shown can bind to growth factors of the TGFs family, suggesting that COMP may also bind to BMP-2.

The application of minimally invasive surgical techniques. Part II: total knee arthroplasty.

Traditional surgical approaches often involve making large skin incisions and extensively dissecting healthy tissue to access diseased anatomy. Obviously more desirable is to make smaller incisions and more focused dissections and achieve the same postsurgical outcomes. Minimally invasive surgery (MIS) is gaining popularity in many orthopedic fields, but MIS techniques are not without risk.

The application of minimally invasive surgical techniques. Part I: total hip arthroplasty.

Traditional surgical approaches often involve making large skin incisions and extensively dissecting healthy tissue to access diseased anatomy. Obviously more desirable is to make smaller incisions and more focused dissections and achieve the same postsurgical outcomes. Minimally invasive surgery (MIS) is gaining popularity in many orthopedic fields, but MIS techniques are not without risk.

Current management options for osteonecrosis of the femoral head: part II, operative management.

Osteonecrosis of the femoral head is a multifactorial disease that can result in significant clinical morbidity and affects patients of any age, including young and active patients. Late sequelae of femoral head osteonecrosis include femoral head collapse and subsequent degeneration of the hip joint. A high index of suspicion and improved radiographic evaluation allow orthopedic surgeons to identify this disease at an earlier stage.

Current management options for osteonecrosis of the femoral head: part 1, diagnosis and nonoperative management.

Osteonecrosis of the femoral head is a multifactorial disease that can result in significant clinical morbidity and affects patients of any age, including young and active patients. Late sequelae of femoral head osteonecrosis include femoral head collapse and subsequent degeneration of the hip joint. A high index of suspicion and improved radiographic evaluation allow orthopedic surgeons to identify this disease at an earlier stage.

Applying computer-assisted navigation techniques to total hip and knee arthroplasty.

Appropriate implant alignment is a major goal of total joint arthroplasty. Obtaining appropriate alignment typically involves making intraoperative decisions in response to visual and tactile feedback. Integrated computer-based systems provide the option of continuous real-time feedback and offer the potential to decrease intraoperative errors while enhancing the surgical learning experience.

Enhanced activity of transforming growth factor β1 (TGF-β1) bound to cartilage oligomeric matrix protein.

Cartilage oligomeric matrix protein (COMP) is an important non-collagenous cartilage protein that is essential for the structural integrity of the cartilage extracellular matrix. The repeated modular structure of COMP allows it to "bridge" and assemble multiple cartilage extracellular matrix components such as collagens, matrilins, and proteoglycans. With its modular structure, COMP also has the potential to act as a scaffold for growth factors, thereby affecting how and when the growth factors are presented to cell-surface receptors.

Total hip arthroplasty in above-knee amputees: a case report.

There are previous case reports in the literature that describe total knee and total hip arthroplasty (THA) in below-knee amputees, but we could find no case reports on above-knee amputees (AKAs) who have severe osteoarthritis of the hip. We present a case involving an AKA who developed severe osteoarthritis of the ipsilateral hip. Out patient underwent THA with a satisfactory postoperative outcome.

Comparison of surgical outcomes and implant wear between ceramic-ceramic and ceramic-polyethylene articulations in total hip arthroplasty.

The results of a prospective multicenter trial comparing 357 hips randomized to total hip arthroplasty with either ceramic-ceramic or ceramic-polyethylene couplings are presented. No statistically significant difference in clinical outcomes scores between the ceramic-ceramic and ceramic-polyethylene groups was observed at any time interval. The mean linear rate was statistically lower (P < .

Differential response of cartilage oligomeric matrix protein (COMP) to morphogens of bone morphogenetic protein/transforming growth factor-β family in the surface, middle and deep zones of articular cartilage.

Cartilage oligomeric matrix protein (COMP) is a prominent non-collagenous component of the extracellular matrix (ECM) in articular cartilage. The regulation of COMP synthesis and secretion is critical for the understanding of cartilage homeostasis in health and disease. We therefore investigated the role of bone morphogenetic protein/transforming growth factor-β (BMP/TGFβ) superfamily members on COMP.