Intraligamentous synovial osteochondroma of the ligamentum teres: a series of 14 cases.

BACKGROUND: The ligamentum teres (LT) is covered by synovium. It acts as a stabilizer of the hip and as such it has been compared to the ACL of the knee joint. Pathologic changes occur in the LT with aging and osteoarthritis (OA), including degeneration, occasional chondroid metaplasia, and synovial chondromatosis are well-recognized in the literature. However, there are no reports of intraligamentous synovial osteochondroma occuring in the LT. METHODS: We reviewed the pathology reports of 542 osteoarthritic femoral arthroplasty specimens between January 2016 and December 2018. The LT was examined histologically in 55 cases because it was abnormal on gross examination. RESULTS: A single synovial osteochondroma, ranging in size from 0.4-1.7 cm in diameter, was present in the body of the LT in 14 cases (9 males; 5 females, aged 34 to 81 years), representing 2.6% of 542 arthroplasty cases. Ten of the osteochondromas had bone marrow fat without hematopoietic elements, 1 had hematopoietic elements, and 3 had no marrow among the bony trabeculae. Radiographically, all cases had moderate to severe osteoarthritis with no mention of an abnormality of LT. CONCLUSION: To our knowledge, this is the first report of intraligamentous synovial osteochondroma in the LT in osteoarthritis patients undergoing hip arthroplasty. It provides further support for microscopic examination of arthroplasty specimens for histologic abnormalities. Further prospective study is needed to determine if this lesion contributes adversely to the development or progression of osteoarthritis and if it is a reactive or neoplastic process.

Academic Orthopaedics As a Driver of Gender Diversity in the Orthopaedic Workforce: A Review of 4,519 Orthopaedic Faculty Members.

BACKGROUND: The purpose of this study was to perform a cross-sectional analysis on the gender composition of practicing academic orthopaedic surgeons using three databases composed of clinical orthopaedic surgeons. METHODS: A comprehensive database of 4,519 clinically active academic orthopaedic surgeons was compiled for this study after the review of publicly available data. The complied data set was evaluated alongside orthopaedic databases obtained from the 2017 Association of American Medical Colleges (AAMC) Faculty Administrative Management Online User System and the 2016 American Academy of Orthopaedic Surgery (AAOS) Orthopaedic Practice in the US census representing the entire academy membership orthopaedic workforce. Gender status was obtained and compared between the three databases. RESULTS: Of the 4,519 clinically active academic orthopaedic surgeons analyzed, 435 (10%) were female compared with 19% for the AAMC faculty database and 7% for the AAOS members. Fourteen percent of women had achieved the rank of professor compared with 25% of the men (P < 0.001). AAMC faculty had a significantly higher percentages of female representation compared with both the clinical faculty (19% versus 10%; P < 0.001) and AAOS members (19% versus 7%; P < 0.001). CONCLUSION: Despite multiple initiatives designed to increase diversity, the 7% female representation in the orthopaedic workforce identified in this study remains markedly lower than other medical and surgical specialties. A higher percentage of women were associated with the AAMC orthopaedic faculty compared with clinically active female surgeons at these institutions. Academic orthopaedic surgeons had greater female representation than the general orthopaedic workforce, highlighting the importance of training institutions at promoting gender equity.

Histiocytic Sarcoma Arising From a Long Bone: Report of Two Cases.

Histiocytic sarcoma is a rare, but aggressive malignant neoplasm of monocyte/macrophage lineage with a wide age distribution. Bone involvement is exceedingly rarer compared to the lymph node, skin, and soft tissue, and no long bone involvement has been reported in the English literature. We here report 2 cases of histiocytic sarcoma involving the long bone: one from the femur of a 77-year-old female, status post the placement of an intramedullary nail for subtrochanteric hip fracture; the other from the radius of a 3-year-old female with no significant medical history. Radiologic imaging showed highly destructive lesions in both cases with soft-tissue extension. Microscopy in both cases showed sheets of polygonal mononuclear cells with abundant eosinophilic cytoplasm, prominent nucleoli, and frequent mitosis. Hemophagocytosis were also identified. Immunohistochemistry showed that the lesional cells were strongly diffusely positive for CD68 and CD163. The first patient deteriorated rapidly, despite the aggressive treatment of amputation and chemotherapy. However, the second patient is disease free 36 months post the treatment of amputation only. We conclude that the long bone could be the primary site of histiocytic sarcoma. Its prognosis could be very variable and it is difficult to predict its behavior based on morphological evaluation only.

The Current Status of Medical School Clerkship Grades in Residency Applicants.

BACKGROUND: Two criteria that have been investigated for evaluating orthopedic surgery residency candidates are achieving an "honors" grade during a surgery clerkship and the total number of honors grades received in all clerkships. Unfortunately, the rate of honors grades given and the criteria for earning an honors grade differ between medical schools, making comparison of applicants from different medical schools difficult. OBJECTIVE: We measured the rate of honors grades in clerkships at different medical schools in the United States to examine the utility of clerkship grades in evaluating orthopedic surgery residency applicants. METHODS: Adequate data via the Electronic Residency Application Service were available for 86 of 142 Association of American Medical Colleges medical schools from the 2017 Match cycle. Descriptive statistics and Wilcoxon rank sum tests were performed to identify differences in grade distributions within each clerkship and in school ranking for research by U.S. News & World Report. RESULTS: For the surgery clerkship, the median rate of honors grades given was 32.5% (range 5%-67%). There was a high rate of interinstitutional variability in all clerkships. We were unable to demonstrate a statistically significant relationship between research ranking and percentage honors grades given for individual clerkships. CONCLUSIONS: A standardized method for grading medical students during clinical clerkships does not exist, resulting in a high degree of interinstitutional variability. Surgery clerkship grades are an unreliable measure for comparing orthopedic surgery residency applicants from different medical schools. Standardized measures of applicant evaluation might be helpful in the future.

Secondary Fracture Prevention: Consensus Clinical Recommendations from a Multistakeholder Coalition.

Osteoporosis-related fractures are undertreated, due in part to misinformation about recommended approaches to patient care and discrepancies among treatment guidelines. To help bridge this gap and improve patient outcomes, the American Society for Bone and Mineral Research assembled a multistakeholder coalition to develop clinical recommendations for the optimal prevention of secondary fractureamong people aged 65 years and older with a hip or vertebral fracture. The coalition developed 13 recommendations (7 primary and 6 secondary) strongly supported by the empirical literature. The coalition recommends increased communication with patients regarding fracture risk, mortality and morbidity outcomes, and fracture risk reduction. Risk assessment (including fall history) should occur at regular intervals with referral to physical and/or occupational therapy as appropriate. Oral, intravenous, andsubcutaneous pharmacotherapies are efficaciousandcanreduce risk of future fracture.Patientsneededucation,however, about thebenefitsandrisks of both treatment and not receiving treatment. Oral bisphosphonates alendronate and risedronate are first-line options and are generally well tolerated; otherwise, intravenous zoledronic acid and subcutaneous denosumab can be considered. Anabolic agents are expensive butmay be beneficial for selected patients at high risk.Optimal duration of pharmacotherapy is unknown but because the risk for second fractures is highest in the earlypost-fractureperiod,prompt treatment is recommended.Adequate dietary or supplemental vitaminDand calciumintake shouldbe assured. Individuals beingtreatedfor osteoporosis shouldbe reevaluated for fracture risk routinely, includingvia patienteducationabout osteoporosisandfracturesandmonitoringfor adverse treatment effects.Patients shouldbestronglyencouraged to avoid tobacco, consume alcohol inmoderation atmost, and engage in regular exercise and fall prevention strategies. Finally, referral to endocrinologists or other osteoporosis specialists may be warranted for individuals who experience repeated fracture or bone loss and those with complicating comorbidities (eg, hyperparathyroidism, chronic kidney disease).

Secondary Fracture Prevention: Consensus Clinical Recommendations from a Multistakeholder Coalition.

Osteoporosis-related fractures are undertreated, due in part to misinformation about recommended approaches to patient care and discrepancies among treatment guidelines. To help bridge this gap and improve patient outcomes, the American Society for Bone and Mineral Research assembled a multistakeholder coalition to develop clinical recommendations for the optimal prevention of secondary fracture among people aged 65 years and older with a hip or vertebral fracture. The coalition developed 13 recommendations (7 primary and 6 secondary) strongly supported by the empirical literature. The coalition recommends increased communication with patients regarding fracture risk, mortality and morbidity outcomes, and fracture risk reduction. Risk assessment (including fall history) should occur at regular intervals with referral to physical and/or occupational therapy as appropriate. Oral, intravenous, and subcutaneous pharmacotherapies are efficacious and can reduce risk of future fracture. Patients need education, however, about the benefits and risks of both treatment and not receiving treatment. Oral bisphosphonates alendronate and risedronate are first-line options and are generally well tolerated; otherwise, intravenous zoledronic acid and subcutaneous denosumab can be considered. Anabolic agents are expensive but may be beneficial for selected patients at high risk. Optimal duration of pharmacotherapy is unknown but because the risk for second fractures is highest in the early post-fracture period, prompt treatment is recommended. Adequate dietary or supplemental vitamin D and calcium intake should be assured. Individuals being treated for osteoporosis should be reevaluated for fracture risk routinely, including via patient education about osteoporosis and fractures and monitoring for adverse treatment effects. Patients should be strongly encouraged to avoid tobacco, consume alcohol in moderation at most, and engage in regular exercise and fall prevention strategies. Finally, referral to endocrinologists or other osteoporosis specialists may be warranted for individuals who experience repeated fracture or bone loss and those with complicating comorbidities (eg, hyperparathyroidism, chronic kidney disease). © 2019 American Society for Bone and Mineral Research.

Recombinant adeno-associated virus-mediated osteoprotegerin gene therapy inhibits wear debris-induced osteolysis.

BACKGROUND: Aseptic loosening of orthopaedic implants secondary to wear debris-induced osteolysis is a serious problem. Osteoprotegerin (OPG) is a natural decoy protein that inhibits osteoclast activation and bone resorption. This study investigated whether gene therapy using a recombinant adeno-associated viral vector that expresses OPG can inhibit wear debris-induced osteolysis. METHODS: A recombinant adeno-associated virus (rAAV) vector co-expressing OPG (rAAV-OPG-IRES-EGFP) was generated. A control vector expressing b-galactosidase (rAAV-LacZ) was also prepared. In vitro validation experiments were performed to determine rAAV-OPG-IRES-EGFP transduction efficiency, OPG expression level and function in bone wafer, and osteoclastic activity. The effect of rAAV-OPG-IRES-EGFP in vivo gene therapy on wear debris-induced osteolysis was then evaluated in a mouse calvarial model in which a single intramuscular injection of the vector was administered prior to the introduction of the wear debris. The effects of the rAAV-OPG-IRES-EGFP gene therapy on wear debris-induced osteoclastogenesis and bone resorption were determined by histomorphometry on day 10. RESULTS: In vitro experiments revealed that 100% of human embryonic kidney 293 cells were transduced at a multiplicity of infection of 1000 with both rAAV-OPG-IRES-EGFP and rAAV-LacZ. At a rAAV-OPG-IRES-EGFP multiplicity of infection of 1000, an OPG concentration of 135 ng/mL of culture media was achieved after four days. Using a bone-wafer assay for osteoclast activity, we found that treatment with rAAV-OPG-IRES-EGFP reduced resorption sevenfold compared with parathyroid hormone-stimulated controls and elevenfold compared with rAAV-LacZ controls. Furthermore, a seventeenfold decrease in RANKL and macrophage colony-stimulating factor-induced splenocyte osteoclastogenesis was observed in co-cultures containing rAAV-OPG-IRES-EGFP-infected fibroblasts. In vivo administration of rAAV-OPG-IRES-EGFP resulted in detectable transduction of myocytes at the injection site and a significant increase in expression of serum OPG levels by the second day (p < 0.05). Maximal concentrations were obtained on day 6 and then leveled off throughout the observation period. In contrast, serum OPG could not be detected in the sham-treated, uninfected titanium-stimulated, or rAAV-LacZ-infected mice. In the control mice, titanium implantation resulted in a threefold increase in the mean number of osteoclasts adjacent to the sagittal suture as well as a twofold increase in the mean area of soft tissue in the sagittal suture compared with the sham-treated mice. In contrast, osteoclast numbers remained at basal levels, and the area of soft tissue in the sagittal suture was markedly reduced in titanium-implanted animals that received rAAV-OPG-IRES-EGFP treatment, demonstrating a complete inhibition of osteolysis in response to titanium particles. CONCLUSIONS: A single intramuscular injection of the rAAV-OPG-IRES-EGFP vector can efficiently transduce myocytes to produce high levels of OPG. The OPG effectively inhibits wear debris-induced osteoclastogenesis and osteolysis. CLINICAL RELEVANCE: Currently, there is no approved drug therapy to prevent or inhibit periprosthetic osteolysis. Although preclinical studies have identified potential drug therapies (i.e., bisphosphonates), there is no evidence that these drugs can effectively treat aseptic loosening in patients. This is the first evidence that in vivo OPG gene therapy can be used to prevent wear debris-induced osteolysis.

Viral interleukin-10 gene inhibition of inflammation, osteoclastogenesis, and bone resorption in response to titanium particles.

OBJECTIVE: To evaluate the potential of viral interleukin-10 (vIL-10) gene therapy as an approach to prevent wear debris-induced inflammation, osteoclastogenesis, and bone resorption as it relates to periprosthetic osteolysis in patients with total joint replacements. METHODS: Replication-defective adenovirus vectors expressing vIL-10 (AdvIL-10) or LacZ (AdLacZ) target genes were used to transduce fibroblast-like synoviocytes (FLS) in vitro, and the effects of these cells on wear debris-induced proinflammatory cytokine production and receptor activator of nuclear factor kappaB ligand + macrophage colony-stimulating factor splenocyte osteoclastogenesis were assessed by enzyme-linked immunosorbent assay and tartrate-resistant acid phosphatase assay. The effects of AdvIL-10 administration on wear debris-induced osteolysis in vivo were analyzed using the mouse calvaria model, in which AdLacZ was used as the control. RESULTS: In the presence of AdLacZ-infected FLS, titanium particle-stimulated macrophages exhibited a marked increase in secretion of tumor necrosis factor alpha (TNFalpha) (6.5-fold), IL-6 (13-fold), and IL-1 (5-fold). Coculture with AdvIL-10-transduced FLS suppressed cytokine secretion to basal levels, while addition of an anti-IL-10 neutralizing antibody completely blocked this effect. The vIL-10-transduced FLS also inhibited osteoclastogenesis 10-fold in an anti-IL-10-sensitive manner. In vivo, titanium implantation resulted in a 2-fold increase in osteoclasts (P < 0.05) and in a 2-fold increase in sagittal suture area (P < 0.05). This increase over control levels was completely blocked in mice receiving intraperitoneal injections of AdvIL-10, all of whom had measurable serum vIL-10 levels for the duration of the experiment. Immunohistochemistry demonstrated reduced cyclooxygenase 2 and TNFalpha expression in AdvIL-10-infected animals. CONCLUSION: This study demonstrates that gene delivery of vIL-10 inhibits 3 processes critically involved in periprosthetic osteolysis: 1) wear debris-induced proinflammatory cytokine production, 2) osteoclastogenesis, and 3) osteolysis.