Republication of "Ankle Fracture-Dislocations: A Review".

Ankle fractures are common musculoskeletal injuries that may result in tibiotalar joint dislocations. Ankle fracture-dislocations occur via similar mechanisms as ankle fractures, although the persistence or magnitude of the deforming force is sufficient to disrupt any remaining bony or soft-tissue stability. Ankle fracture-dislocations likely represent distinct clinical entities, as the pathology, management, and patient outcomes following these injuries differ from those seen in more common ankle fractures without dislocation. Ankle fracture-dislocations have higher rates of concomitant injury including open fractures, chondral lesions, and intra-articular loose bodies. Long-term outcomes in ankle fracture-dislocations are worse than ankle fractures without dislocation. Higher rates of posttraumatic osteoarthritis and chronic pain have also been reported. In this review, we discuss the current literature regarding the history, management, and outcomes of ankle-fracture dislocations and highlight the need for future study.

Migration Patterns for Revision Total Knee Arthroplasty in the United States as Reported in the American Joint Replacement Registry.

BACKGROUND: Revision total knee arthroplasty (TKA) is associated with a higher complication rate and a greater cost when compared to primary TKA. Based on patient choice, referral, or patient transfers, revision TKAs are often performed in different institutions by different surgeons than the primary TKA. The aim of this study is to evaluate the effect of hospital size, teaching status, and revision indication on the migration patterns of failed primary TKA in patients 65 years of age and older. METHODS: All primary and revision TKAs reported to the American Joint Replacement Registry from January 2012 through March 2020 were included and merged with the Centers for Medicare and Medicaid Services database. Migration was defined as a patient having a primary TKA and revision TKA performed at separate institutions by different surgeons. RESULTS: In total, 9167 linked primary and revision TKAs were included in the analysis. Overall migration rates were significantly higher from small (<100 beds; P = .019), non-teaching institutions (P = .002) driven primarily by patients diagnosed with infection. Infection patients had significantly higher migration rates from small (46.8%, P < .001), non-teaching (43.5%, P < .001) institutions, while migration rates for other causes of revision were statistically similar. Most patients migrated to medium or large institutions (84.7%) for revision TKA rather than small institutions (15.3%, P < .001) and to teaching (78.3%) rather than non-teaching institutions (21.7%, P < .001). CONCLUSION: There is a diagnosis-dependent referral bias that affects the migration rates of infected primary TKA from small non-teaching institutions leading to a flow of more medically complex patients to medium and large teaching institutions for infected revision TKA.

Anterior Percutaneous-Assisted Total Hip Arthroplasty: Surgical Technique and Early Outcomes.

BACKGROUND: Percutaneous-assisted arthroplasty was introduced to minimize complications traditionally associated with minimally invasive techniques, such as component malposition and periprosthetic fracture. Proponents of percutaneous-assisted techniques have more than 15 years of clinical utilization with good outcomes. This study reports our early experience, and outcomes, with an anterior percutaneous-assisted total hip arthroplasty (AnteriorPath). METHODS: A retrospective evaluation of a single-surgeon experience with the first 46 patients undergoing AnteriorPath using a cannula for acetabular cup instrumentation was compared with a similar-sized cohort undergoing traditional direct anterior (DA) total hip arthroplasty. Patients needed at least 2 postoperative visits for inclusion. Baseline preoperative characteristics, operative time, component positioning, and 6-week all-cause complications were evaluated. P values <.05 were considered statistically significant. RESULTS: Longer operative times were experienced with the AnteriorPath vs DA THA (93.6 minutes ± 38.6 vs 79.6 minutes ± 23.2, respectively, P = .0503). There were no significant differences in component abduction (40.14° DA vs 41.95° AnteriorPath, P = .1058). A statistically significant difference was found in component anteversion (32.8° DA vs 27.25° AnteriorPath, P = .0039). There were higher rates of short-term complications in patients undergoing DA THA (9.09% DA vs 2.5% AnteriorPath). CONCLUSIONS: Early experience with an AnteriorPath demonstrates similar short-term outcomes compared with traditional DA THA. The use of a percutaneous technique has also allowed for a smaller incision, in-line acetabular cup reaming and impaction under direct visualization, and limited trauma to surrounding soft tissues. Further long-term studies with a larger sample size are needed to evaluate the potential benefits and complications of this novel technique.

Risk Adjustment in the California Joint Replacement Registry: Is Patient Complexity Accurately Assessed in Academic Versus Nonacademic Hospitals?

BACKGROUND: We sought to report on the differences in observed versus expected arthroplasty outcomes between academic and nonacademic hospitals in a large joint registry. We utilized the California Joint Replacement Registry's data and risk adjustment model. METHODS: Observed versus expected hip and knee arthroplasty complications were utilized to assess hospital and surgeon risk-adjusted complication rates (RACRs). Based on a hospital and surgeon RACR, each was assigned a performance rating ("worse," "expected," "better"). Associations between academic status and performance ratings, rates of individual complications, prevalence of risk factors associated with increased complication rates, and differences in complication rates were calculated. RESULTS: A higher percentage of academic providers had "worse" than expected ratings, whereas a higher percentage of nonacademic providers had "expected" and "better" than expected ratings (P = .011) based on the observed versus expected complication rates. There was a higher incidence of patients with congestive heart failure and an elevated American Society of Anesthesiologists classification in academic institutions (P = .0001). The complication rate was higher in academic institutions for all total knee arthroplasties (P < .0016). CONCLUSIONS: We identified disparities in RACRs between nonacademic and academic institutions. This may reflect the difficulty of fully adjusting for medical risk and surgical complexity in a large arthroplasty database.

Preoperative Patient-Recorded Outcome Measures Predict Patient Discharge Location Following Unicondylar Knee Arthroplasty.

BACKGROUND: Advantages of unicondylar knee arthroplasty (UKA) over total knee arthroplasty include rapid recovery and shorter lengths of stay following surgery. Patients requiring extended postoperative care fail to recognize these benefits. Patient-reported outcome measures have proved useful in predicting outcomes following joint arthroplasty. The purpose of this study was to identify and report preoperative patient-reported outcome measures and clinical variables that predict discharge to skilled nursing facilities following UKA. METHODS: A prospective cohort of 174 patients was used to collect 36-Item Short Form scores and objective clinical data. Univariate and multivariate analysis with backward elimination were conducted to find a predictive risk model. RESULTS: The predictive model reported (78.7% concordance, receiver operating characteristic curve c-statistic 0.719, P = .0016) demonstrates that risk factors for discharge to skilled nursing facilities are: older age (odds ratio 4.18; 95% confidence interval [CI] 1.256-13.911, P = .019), bilateral UKA procedures (odds ratio 1.887; 95% CI 1.054-3.378, P = .0326) and lower patient-reported preoperative 36-Item Short Form physical function scores (odds ratio 0.968; CI 0.938-1, P = .0488). CONCLUSION: The information presented here regarding possible patient disposition following UKA could aid informed decision-making regarding patients' short-term needs following surgery and help streamline preoperative planning.

Lumbar corpectomy for correction of degenerative scoliosis from osteoradionecrosis reveals a delayed complication of lumbar myxopapillary ependymoma.

Osteoradionecrosis is a known complication following radiation therapy, presenting most commonly in the cervical spine as a delayed consequence of radiation that is often necessary in the management of head and neck cancers. In contrast, osteoradionecrosis has rarely been described in the lumbar spine. Here we describe, to our knowledge, the first reported case of lumbar spine osteoradionecrosis, after adjuvant radiation for a primary spinal cord tumor, leading to progressive degenerative scoliosis which required subsequent operative management. Established guidelines recommend that mature bone can tolerate a dose of up to 6000 cGy without injury. However, once bone has been exposed to radiation over this level progressive soft tissue changes may lead to devascularization, leaving the bone vulnerable to osteonecrosis, specifically when manipulated. Radiation necrosis can be progressive and lead to eventual mechanical instability requiring debridement and surgical fixation. In the setting of the lumbar spine, osseous necrosis can lead to biomechanical instability, deformity, pain, and neurologic deficit.

Evaluation of Internet Information About Rotator Cuff Repair.

The content and quality of Internet websites are not governed or regulated. Therefore, patients who consult the Internet may receive outdated or incorrect medical information. Researchers have analyzed the quality of web information about various orthopedic surgeries, but no such analysis has been performed on websites covering rotator cuff repair. We conducted a study to evaluate and analyze rotator cuff repair information available to the general public through the Internet; to assess changes in the quality of information over time; to determine if sites sponsored by academic institutions offered higher-quality information; and to assess whether the readability of the material varied according to DISCERN scores. Two Internet searches were conducted, in 2011 and 2014. The 3 most commonly used search engines were used to search for rotator cuff repair. The first 50 websites from each search engine were evaluated for authorship and content. The DISCERN instrument was used to analyze the quality of each website's health information. The 2011 search revealed 21% of websites were associated with an academic institution, 38% were authored by a hospital or physician group, and 11.5% were industry-sponsored. The 2014 search revealed a similar distribution of contributors. The highest DISCERN scores were given to academic institution websites (51.6) and public education websites (49). There was no correlation between readability and DISCERN scores. Websites associated with academic institutions produced the highest-quality medical information. Over the past few years, authorship and content have changed little with respect to Internet information about rotator cuff repair.

ESET histone methyltransferase regulates osteoblastic differentiation of mesenchymal stem cells during postnatal bone development.

To investigate the effects of histone methyltransferase ESET (also known as SETDB1) on bone metabolism, we analyzed osteoblasts and osteoclasts in ESET knockout animals, and performed osteogenesis assays using ESET-null mesenchymal stem cells. We found that ESET deletion severely impairs osteoblast differentiation but has no effect on osteoclastogenesis, that co-transfection of ESET represses Runx2-mediated luciferase reporter while siRNA knockdown of ESET activates the luciferase reporter in mesenchymal cells, and that ESET is required for postnatal expression of Indian hedgehog protein in the growth plate. As the bone phenotype in ESET-null mice is 100% penetrant, these results support ESET as a critical regulator of osteoblast differentiation during bone development.

Mesenchyme-specific knockout of ESET histone methyltransferase causes ectopic hypertrophy and terminal differentiation of articular chondrocytes.

The exact molecular mechanisms governing articular chondrocytes remain unknown in skeletal biology. In this study, we have found that ESET (an ERG-associated protein with a SET domain, also called SETDB1) histone methyltransferase is expressed in articular cartilage. To test whether ESET regulates articular chondrocytes, we carried out mesenchyme-specific deletion of the ESET gene in mice. ESET knock-out did not affect generation of articular chondrocytes during embryonic development. Two weeks after birth, there was minimal qualitative difference at the knee joints between wild-type and ESET knock-out animals. At 1 month, ectopic hypertrophy, proliferation, and apoptosis of articular chondrocytes were seen in the articular cartilage of ESET-null animals. At 3 months, additional signs of terminal differentiation such as increased alkaline phosphatase activity and an elevated level of matrix metalloproteinase (MMP)-13 were found in ESET-null cartilage. Staining for type II collagen and proteoglycan revealed that cartilage degeneration became progressively worse from 2 weeks to 12 months at the knee joints of ESET knock-out mutants. Analysis of over 14 pairs of age- and sex-matched wild-type and knock-out mice indicated that the articular chondrocyte phenotype in ESET-null mutants is 100% penetrant. Our results demonstrate that expression of ESET plays an essential role in the maintenance of articular cartilage by preventing articular chondrocytes from terminal differentiation and may have implications in joint diseases such as osteoarthritis.

ESET histone methyltransferase is essential to hypertrophic differentiation of growth plate chondrocytes and formation of epiphyseal plates.

The ESET (also called SETDB1) protein contains an N-terminal tudor domain that mediates protein-protein interactions and a C-terminal SET domain that catalyzes methylation of histone H3 at lysine 9. We report here that ESET protein is transiently upregulated in prehypertrophic chondrocytes in newborn mice. To investigate the in vivo effects of ESET on chondrocyte differentiation, we generated conditional knockout mice to specifically eliminate the catalytic SET domain of ESET protein only in mesenchymal cells. Such deletion of the ESET gene caused acceleration of chondrocyte hypertrophy in both embryos and young animals, depleting chondrocytes that are otherwise available to form epiphyseal plates for endochondral bone growth. ESET-deficient mice are thus characterized by defective long bone growth and trabecular bone formation. To understand the underlying mechanism for ESET regulation of chondrocytes, we carried out co-expression experiments and found that ESET associates with histone deacetylase 4 to bind and inhibit the activity of Runx2, a hypertrophy-promoting transcription factor. Repression of Runx2-mediated gene transactivation by ESET is dependent on its H3-K9 methyltransferase activity as well as its associated histone deacetylase activity. In addition, knockout of ESET is associated with repression of Indian hedgehog gene in pre- and early hypertrophic chondrocytes. Together, these results provide clear evidence that ESET controls hypertrophic differentiation of growth plate chondrocytes and endochondral ossification during embryogenesis and postnatal development.

Evaluation of information available on the Internet regarding anterior cruciate ligament reconstruction.

Searching the Internet is one of the most popular methods for acquiring information related to health. The Internet offers physicians and patients easy access to a wide range of medical material from anywhere in the world. For many patients, this information helps formulate decisions related to their health and health care. An important caveat is that virtually anything can be published on the Internet. Although academic publications require rigorous peer review, Internet websites have no regulatory body monitoring quality and content. With a lack of external regulation, the information retrieved may be incorrect or outdated. The Internet can be a valuable asset for educating patients, but because of significant variability physicians should be familiar with the quality of information available. This article discusses both the strengths and weaknesses of information available on the Internet regarding anterior cruciate ligament repair.