Synovial Lipomatosis of the Glenohumeral Joint

Synovial lipomatosis (also known as lipoma arborescens) is a rare and benign lesion affecting synovium-lined cavities. It is characterized by hyperplasia of mature fat tissue in the subsynovial layer. Although the most commonly affected site is the knee joint, rarely additional locations such as tendon sheath and other joints are involved. We present a case of synovial lipomatosis of the glenohumeral joint in a 44-year-old man. The clinical data radiological studies and histopathologic results are described, as well as a review of the current literature

Cigarette Smoking Is Associated with a Lower Concentration of CD105+ Bone Marrow Progenitor Cells

Cigarette smoking is associated with musculoskeletal degenerative disorders, delayed fracture healing, and nonunion. Bone marrow progenitor cells (BMPCs), known to express CD105, are important in local trophic and immunomodulatory activity and central to musculoskeletal healing/regeneration. We hypothesized that smoking is associated with lower levels of BMPC. Iliac bone marrow samples were collected from individuals aged 18–65 years during the first steps of pelvic surgery, under IRB approval with informed consent. Patients with active infectious or neoplastic disease, a history of cytotoxic or radiation therapy, primary or secondary metabolic bone disease, or bone marrow dysfunction were excluded. Separation process purity and the number of BMPCs recovered were assessed with FACS. BMPC populations in self-reported smokers and nonsmokers were compared using the two-tailed t-test. 13 smokers and 13 nonsmokers of comparable age and gender were included. The average concentration of BMPCs was 3.52 × 105/mL ± 2.45 × 105/mL for nonsmokers versus 1.31 × 105/mL ± 1.61 × 105/mL for smokers (t= 3.2, P=0.004). This suggests that cigarette smoking is linked to a significant decrease in the concentration of BMPCs, which may contribute to the reduced regenerative capacity of smokers, with implications for musculoskeletal maintenance and repair

Tranexamic Acid Treatment Reduces Blood Loss After Elective and Semi-Urgent Reverse Total Shoulder Arthroplasty

Introduction Post operative blood loss after reverse shoulder arthroplasty (RSA) is associated with the need for blood transfusion and prolonged hospital stay, among other complications. Tranexamic acid (TXA) reduces perioperative blood loss and is effective when delivered systemically or locally. We compared the effects of TXA on perioperative blood loss between elective and semi-urgent RSA. Methods We retrospectively reviewed patients who underwent either elective or semi-urgent RSA for fracture repair, with and without TXA treatment. Demographics, clinical records, and laboratory results were collected and analyzed to compare peripheral blood hemoglobin concentrations before and after surgery, the need for blood transfusion, and length of hospital stay between the 2 groups. Results In a cohort of 158 patients, 91 (58%) underwent elective RSA. TXA was administered in 91 (58%) patients from the entire group. TXA administration was associated with a significant decrease in post operative hemoglobin concentration reduction in both the elective and fracture groups ( P = .026 and P = .018, respectively), a significant decrease in post operative blood transfusion rates ( P = .004 and P = .003, respectively), and a decrease in the need for prolonged hospitalization ( P = .038 and P = .009, respectively). Discussion The local application of TXA during RSA yielded a significant reduction in perioperative blood loss. We showed a significant positive effect of local TXA administration during RSA that is comparable for both elective and semi-urgent patients. Due to the baseline characteristics of fracture patients, their clinical benefits may be more notable. Conclusions The positive outcomes for surgical patients with the use of TXA during RSA can possibly cause future consideration in clinical practice

Sirt1 Promotes a Thermogenic Gene Program in Bone Marrow Adipocytes: From Mice to (Wo)Men

Bone marrow adipose tissue (MAT) is influenced by nutritional cues, and participates in whole body energy metabolism. To investigate the role of Sirtuin1 (Sirt1), a key player in metabolism, in MAT, marrow adiposity was evaluated in inbred 5-month-old 129/Sv Sirt1 haplo-insufficient (Sirt1Δ/+) and wild type (WT) mice. Decreased expression of the thermogenic genes: Prdm16, Pgc1α, Foxc2, Dio2, and β3AR was detected in whole tibiae derived from Sirt1Δ/+ compared to WT female mice. Similarly, decreased expression of Prdm16 and Pgc1α was observed in primary bone marrow mesenchymal stem cell (BM-MSC) cultures obtained from Sirt1Δ/+ compared to WT female mice, suggesting a cell autonomous effect of Sirt1 in BM-MSCs. In vitro, Sirt1 over-expression in the mesenchymal embryonic fibroblast stem cell line C3HT101/2 increased Pgc1α and Prdm16 protein level. Similarly, pharmacologic activation of Sirt1 by SRT3025 increased Foxc2, Pgc1α, Dio2, Tfam, and Cyc1 expression while inhibition of Sirt1 by EX527 down-regulated UCP1 in C3HT101/2 cells. Importantly, in human femoral BM-MSCs obtained from female patients undergoing hip operations for fracture or osteoarthritis, Sirt1 activation by SRT3025 increased PGC1α mRNA and protein level. Blocking sclerostin, an inhibitor of the WNT pathway and a Sirt1 target, by the monoclonal humanized antibody (Sc-AbII), stimulated β3AR, PRDM16, and UCP1 gene expression, and increased PGC1α protein level. These results show that Sirt1 stimulates a thermogenic gene program in marrow adipocytes in mice and humans via PGC1α activation and sclerostin inhibition. The implications of these findings to bone health, hematopoiesis and whole body energy metabolism remain to be investigated.ISSN:1664-239

Spine Robot-Assisted Vertebral Body Augmentation A Radiation Reduction Tool

Study Design. Retrospective. Objective. To assess radiation exposure time during robot-guided vertebral body augmentation compared with other published fi ndings. Summary of Background Data. Rising incidence of vertebral compression fractures in the aging population result in widespread use of vertebral body cement augmentation with signifi cant radiation exposure to the surgeon, operating room staff, and patient. Radiation exposure leads to higher cancer rates among orthopedic and spine surgeons and patients. Methods. Thirty-three patients with 60 vertebral compression fractures underwent robot-guided vertebral body augmentation performed by 2 surgeons simultaneously injecting cement at 2 levels under pulsed fl uoroscopy. The age of patients was in the range from 29 to 92 (mean, 67 yr). One to 6 vertebrae were augmented per case (average 2). Twenty-fi ve patients had osteoporotic fractures and 8 had pathological fractures. Robotic guidance data included execution rate, accuracy of guidance, total surgical time, and time required for robotic guidance. Radiation-related data included the average preoperative computed tomographic effective dose, radiation time for calibration, registration, placement of Kirschner wires, and total procedure radiation time. Radiation time per level and surgeon's exposure were calculated. Results. Kyphoplasty was performed in 15 patients (1 sacroplasty), vertebroplasty in 13, and intravertebral expanding implants in 5. The average preoperative computed tomographic effective dose was 50 mSv (18-81). Average operative time was 118 minutes (49-350). Mean robotic guidance took 36 minutes. Average operative radiation time was 46.1 seconds per level (33-160). Average exposure time From the