; and Summa Health Systems, Akron, Ohio (IG) S U M M A R Y To test the hypothesis that a perturbation of endoplasmic reticulum (ER) function is involved in the pathogenesis of osteoarthritis (OA), articular cartilage was isolated from non-OA patients secondary to resection of osteo-or chondrosarcomas. Intra-joint samples of minimal and advanced osteoarthritic cartilage were isolated from patients undergoing total knee arthroplasty and scored for disease severity. Glucose-regulated protein-78 (grp78) and bcl-2-associated athanogene-1 (bag-1) were detected via immunofluorescence as markers of non-homeostatic ER function. Additionally, the expression of type VI collagen and its integrin receptor, NG2, was determined to examine cartilage matrix health and turnover. There was an upregulation of grp78 in advanced OA, and variable expression in minimal OA. Non-OA cartilage was consistently grp78 negative. The downstream regulator bag-1 was also upregulated in OA compared with normal cartilage. Collagen VI was mainly cellassociated in non-OA cartilage, with a more widespread distribution observed in OA cartilage along with increased intracellular staining intensity. The collagen VI integral membrane proteoglycan receptor NG2 was downregulated in advanced OA compared with its patientmatched minimally involved cartilage sample. These results suggest that chondrocytes exhibit ER stress during OA, in association with upregulation of a large secreted molecule, type VI collagen. (J Histochem Cytochem 57:923-931, 2009) K E Y W O R D S osteoarthritis cartilage ER stress bag-1 grp78 collagen VI NG2 OSTEOARTHRITIS (OA) IS A PROGRESSIVE DISEASE, with changes in chondrocyte gene expression and extracellular matrix (ECM) composition occurring before macroscopic structural damage is observed (Hamerman 1989). Articular chondrocytes in OA exhibit a hypermetabolic phenotype, with studies describing highly proliferative clonal chondrocytes, along with the upand downregulation of ECM molecules such as aggrecan
A three-dimensional computer model of a total hip replacement was used to examine the relationship between the position of the components, the range of motion and the prosthetic joint contact area. Horizontal acetabular positions with small amounts of acetabular and femoral anteversion provide the largest contact areas, but result in limited joint movement. These data will allow surgeons to select implant positions that will provide the largest possible joint contact area for a given joint range of motion although these are conflicting goals. In some component positions a truncated spherical prosthetic head resulted in smaller contact areas than a completely spherical head.
Low back pain is one of the most common reasons for physician visits in the United States and is a chief complaint frequently seen by orthopedic surgeons. Patients with chronic low back pain can experience recurring debilitating pain and disability, decreasing their quality of life. A commercially available software platform, Explorys (Explorys, Inc, Cleveland, Ohio), was used to mine a pooled electronic health care database consisting of the medical records of more than 26 million patients. According to the available medical history data, 1.2 million patients had a diagnosis of low back pain (4.54%). The information was used to determine the incidence of low back pain in patients with a history of nicotine dependence, obesity (body mass index, >30 kg/m(2)), depressive disorders, and alcohol abuse. Relative risk was then calculated for the defined modifiable risk factors. Patients with nicotine dependence, obesity, depressive disorders, and alcohol abuse had a relative risk of 4.489, 6.007, 5.511, and 3.326 for low back pain, respectively, compared with patients without the defined risk factor. A statistically significant difference was found in the incidence of low back pain between all 4 groups with the risk factors evaluated and the general population (P<.05). By determining treatable patient risk factors for low back pain, physicians can monitor at-risk patients and focus on prevention and control of debilitating disease. These approaches can decrease the number of patients with isolated low back pain who are seen by orthopedic surgeons. [Orthopedics. 2016; 39(3):e413-e416.].
A three-dimensional computer model of a total hip replacement was used to examine the relationship between the position of the components, the range of motion and the prosthetic joint contact area. Horizontal acetabular positions with small amounts of acetabular and femoral anteversion provide the largest contact areas, but result in limited joint movement. These data will allow surgeons to select implant positions that will provide the largest possible joint contact area for a given joint range of motion although these are conflicting goals. In some component positions a truncated spherical prosthetic head resulted in smaller contact areas than a completely spherical head.
Several orthopedic registries have described the incidence of total knee arthroplasty (TKA) in patients who have undergone knee arthroscopy. Patient risk factors may play a role in the conversion rate from knee arthroscopy to TKA. This study quantifies the incidence of conversion of knee arthroscopy to TKA from a US mixed-payer database and describes some common patient risk factors for conversion. The medical records of more than 50 million patients who were treated between 1998 and 2014 were mined with a commercially available software platform. During the study period, a total of 68,090 patients older than 50 years underwent knee arthroscopy for partial meniscectomy, chondroplasty, or debridement. Reported rates of TKA at 1, 2, and 3 years after arthroscopy were 10.1%, 13.7%, and 15.6%, respectively. Obesity, depressive disorder, rheumatoid arthritis, diabetes, and age 70 years and older were associated with increased relative risk of conversion to TKA at 2 years. When obesity was combined individually with the top 5 other risk factors, no combination produced a higher relative risk than that of obesity alone. Patients who were 50 to 54 years of age had the lowest incidence of conversion to TKA (8.3%, P<.001). Men had a lower incidence of conversion to TKA (11.3%) than women (15.8%, P<.001). This information can help surgeons to counsel patients on the incidence of TKA after knee arthroscopy and identify preoperative risk factors that increase risk. [Orthopedics. 2016; 39(6):e1041-e1044.].
This study investigated surgeons’ perceptions of their experience while adopting a novel CAOS enhanced mechanical instrument system for TKA, including ease of usage, task complexity, and demands of surgical time and physical activity. A group of 9 surgeons from multiple countries with no experience in the investigated system used the CAOS enhanced mechanical instrument system during their surgical practice. After performing each TKA case, the surgeon independently completed a 6-section questionnaire formulated to survey his/her experience with the case. The results demonstrated high level of surgeons’ experiences with the adoption of the CAOS enhanced conventional instrumentation, with particularly satisfying experiences in minimum demand of time in landmark acquisition and disruption of the existing surgical process.
IntroductionPreoperative planning for total hip arthroplasty (THA) is an essential step taken to reduce surgical errors and improve patient outcomes. Previously, templating using acetate radiographs proved accurate and beneficial. However, digital templating of digitally acquired radiographs has become more commonplace. The purpose of this study was to quantify accuracy of digital templating for THA’s performed by a single surgeon over a 4-year period and to determine if accuracy improved over time. Materials and Methods491 patients undergoing primary THA from 2013-2017 performed by a single surgeon were retrospectively analyzed. Digital templating was performed using ORTHOVIEW Orthopaedic Digital Templating for CARESTREAM PACS (© 2019 Carestream Health). Digitally templated acetabular and femoral component sizes were compared to actual implanted sizes to determine template percent accuracy. To investigate changes in accuracy over time, THA cases were divided in half and compared. Chi Square and Fisher’s Exact Tests were used to determine statistically significant differences in percent accuracy over time. Results Overall percent accuracy of acetabular and femoral components was 97.4% and 87.2% respectively. When comparing the first and second half, percent accuracy of acetabular and femoral components was 98.4% versus 97.1% (P =0.58) and 89.4% versus 84.9% (P= 0.14) respectively. ConclusionsThis study represents one of the largest retrospective analyses aimed at determining accuracy of digital templating in THA procedures performed by a single surgeon at a single institution. Percent accuracy was consistently high throughout time and deemed an accurate methodology for preoperative planning of cementless THA.
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