Do Demographic or Anthropometric Factors Affect Lateralization of the Tibial Tubercle in a Diverse Population? A Magnetic Resonance Imaging Analysis.

INTRODUCTION: The tibial tubercle-trochlear groove (TT-TG) distance is commonly used to evaluate and guide treatment for patellar instability. There is limited data available regarding TT-TG variability based on patient demographics and anthropometric factors. MATERIALS AND METHODS: TT-TG was measured on magnetic resonance imaging (MRI) for 384 consecutive adult patients. Demographic information for the corresponding was then gathered from the medical record and analyzed. Demographic variables analyzed included age, sex, race, height, weight, and body mass index (BMI). RESULTS: Mean TT-TG among the 384 patients was 12.68mm (standard deviation [SD]: 4.13mm, 95% confidence interval [CI] 12.26-13.10mm, range, 3.2-27.0mm), and there was a significant correlation with height (p=0.009), weight (p=0.017), and race (p<0.001). However, there was no significant correlation seen with sex (p=0.854), BMI (p=0.253), or age (p=0.096). Height and African American race were identified as independent predictors of increased TT-TG (p=0.007 and p<0.001, respectively); and females were found to have an increased TT-TG relative to height (p=0.015). CONCLUSION: Tibial tubercle-trochlear groove distance was significantly correlated with race and height in the 384 patients examined. These findings may help explain clinical differences in these patients and help establish "norms" for patients of various ethnic and anthropometric variability.

Co-chaperone Hsp70/Hsp90-organizing protein (Hop) is required for transposon silencing and Piwi-interacting RNA (piRNA) biogenesis.

Piwi-interacting RNAs (piRNAs) are 26-30-nucleotide germ line-specific small non-coding RNAs that have evolutionarily conserved function in mobile genetic element (transposons) silencing and maintenance of genome integrity. Drosophila Hsp70/90-organizing protein homolog (Hop), a co-chaperone, interacts with piRNA-binding protein Piwi and mediates silencing of phenotypic variations. However, it is not known whether Hop has a direct role in piRNA biogenesis and transposon silencing. Here, we show that knockdown of Hop in the germ line nurse cells (GLKD) of Drosophila ovaries leads to activation of transposons. Hop GLKD females can lay eggs at the same rate as wild-type counterparts, but the eggs do not hatch into larvae. Hop GLKD leads to the accumulation of γ-H2Av foci in the germ line, indicating increased DNA damage in the ovary. We also show that Hop GLKD-induced transposon up-regulation is due to inefficient piRNA biogenesis. Based on these results, we conclude that Hop is a critical component of the piRNA pathway and that it maintains genome integrity by silencing transposons.

Total joint arthroplasty in cancer patients.

Increasing numbers of total joint arthroplasty (TJA) patients have a history, or an active diagnosis, of cancer. We aimed to evaluate the risk of early postoperative complications in these patients. In our series, a history of malignancy was associated with an elevated risk of ischemic cardiac events and postoperative deep vein thrombosis (DVT), while active malignancy was associated with increased respiratory and renal complications, hematoma/seroma formation and early postoperative mortality. Both groups presented increased rates of overall in-hospital complications. Patients with bone metastasis to the hip demonstrated increased DVT and 90-day mortality rates. Cancer patients have increased morbidity and mortality after TJA and should undergo comprehensive medical optimization and adapted thromboprophylaxis.

Fewer postoperative fevers: an unexpected benefit of multimodal pain management?

BACKGROUND: Elevated temperatures after total joint arthroplasty (TJA) are common and can be a source of anxiety both for the patient and the surgical team. Although such fevers rarely are caused by acute infection, many patients are subjected to extensive testing for elevated body temperature after surgery. We recently implemented a multimodal pain management regimen for TJA, which includes acetaminophen, pregabalin, and celecoxib or toradol, and because some of these medications have antipyrexic properties, it was speculated that this protocol might influence the frequency of postoperative pyrexia. QUESTIONS/PURPOSES: The purpose of this study was to determine whether patients treated under this protocol were less likely to exhibit postoperative fever after primary TJA, compared with a historical control group, and whether they were less likely to receive postoperative testing as part of a fever workup. METHODS: We compared 1484 primary TJAs in which pain was controlled primarily with opioid-based relief from July 2004 to December 2006 with 2417 procedures from July 2009 to December 2011 during which time multimodal agents were used. The same three surgeons were responsible for care in both of these cohorts. Oral temperature readings in the first 5 postoperative days (POD) were drawn from a review of medical records, which also were evaluated for fever workup tests, including urinalysis, urine culture, chest radiograph, and blood culture. Fever was defined by the presence of a temperature measurement over 38.5 °C. Patients having preoperative fever or postoperative fever starting later than POD 5 were excluded. Before surgery, there were no differences between the groups' temperature measurements. RESULTS: Fewer patients developed fever in the multimodal analgesia group than in the control group (5% versus 25%, p < 0.001). Furthermore, fewer patients underwent workup for fever in the multimodal analgesia cohort (1.8% of patients undergoing 155 individual tests) compared with the control cohort (9.8% of patients undergoing 247 individual tests; p < 0.001). CONCLUSIONS: In addition to fewer adverse effects and better pain control, the multimodal analgesia protocol has the hidden benefit of dampening the temperature response to the surgical insult of TJA. The decreased rate of postoperative fever avoids unnecessary anxiety for the patient and the treating team and reduces healthcare resource use occasioned by working up postoperative fever. LEVEL OF EVIDENCE: Level III, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

Evaluation of the efficacy and safety of tranexamic acid for reducing blood loss in bilateral total knee arthroplasty.

Tranexamic acid (TA) has been reported to reduce blood loss after total joint arthroplasty; however, the literature is sparse in evaluating its efficacy in simultaneous bilateral total knee arthroplasty (TKA). In this retrospective study of consecutive patients, TA use in bilateral TKA was associated with a significant reduction in perioperative serum hemoglobin drop, as well as allogeneic blood transfusion needs from 50% to 11% of patients. No autologous blood donation or drains were used. There were no venous thromboembolic events reported. Implementation of a systematic intravenous TA protocol in simultaneous bilateral TKA appears highly effective in reducing transfusion requirements, potentially reducing healthcare resource utilization as well as the morbidity and complications associated with allogeneic blood transfusions.

Aquacel surgical dressing reduces the rate of acute PJI following total joint arthroplasty: a case-control study.

An effort to prevent PJI has led to the development of antimicrobial dressings that support wound healing. We sought to determine whether Aquacel Surgical dressing independently reduces the rate of acute PJI following TJA. A single institution retrospective chart review of 903 consecutive cases who received the Aquacel Surgical dressing and 875 consecutive cases who received standard gauze dressing was conducted to determine the incidence of acute PJI (within 3 months). The incidence of acute PJI is 0.44% in the Aquacel dressing group compared to 1.7% in the standard gauze dressing group (P = 0.005). Multivariate analysis revealed that use of Aquacel dressing was an independent risk factor for reduction of PJI (odds ratio of 0.165, 95% confidence interval: 0.051-0.533). Aquacel Surgical dressing significantly reduces the incidence of acute PJI.

Clostridium difficile is common in patients with postoperative diarrhea after hip and knee arthroplasty.

Clostridium difficile is an antibiotic-associated gastrointestinal infection that has detrimental consequences. We sought to determine the incidence of C. difficile in TJA patients with postoperative diarrhea, to determine risk factors for C. difficile infection, and to establish the incidence of C. difficile-related complications. Our institutional protocol includes screening for C. difficile in all patients with diarrhea after TJA. We identified 121 such patients over four years with twenty-eight (23%) testing positive for C. difficile. Revision arthroplasty and prolonged postoperative antibiotic use were risk factors for C. difficile infection. With our protocol of screening and immediate treatment of C. difficile positive patients, we found no C. difficile-associated complications.

Long term cost outcomes among commercially insured patients undergoing bariatric surgical procedures.

Objective: Bariatric procedures have become safer in recent years, warranting new data on long-term costs. This study examined the impact of bariatric procedures on a person's long-term healthcare costs up to 10 years and if it differed by socio-economic status (SES). Methods: This retrospective observational study compared the downstream health care cost of patients with obesity who had undergone bariatric surgery (BS) between 2009 and 2018 to a 1:1 matched group of members with obesity but no surgery. Results: 167,764 individuals from administrative claims data with an obesity diagnosis were included; 83,882 in the BS group and 83,882 in the non-surgical group. In follow-up years 2-10, the BS group was associated with lower total medical healthcare cost compared to the non-surgical group (cost ratios ranged 0.85-0.93, p values < 0.05). When stratifying the BS group by SES quartiles, there were no significant cost differences by SES (cost ratios ranged from 0.96 to 1.05, most p values > 0.05). Conclusions: BS was associated with lower long-term follow-up medical cost and cost savings appeared similar among the SES quartiles in the BS group. The study results may help policy makers and employers in designing benefits and extending coverage for bariatric surgical procedures.

Metabolic reprogramming by Syntenin-1 directs RA FLS and endothelial cell-mediated inflammation and angiogenesis.

A novel rheumatoid arthritis (RA) synovial fluid protein, Syntenin-1, and its receptor, Syndecan-1 (SDC-1), are colocalized on RA synovial tissue endothelial cells and fibroblast-like synoviocytes (FLS). Syntenin-1 exacerbates the inflammatory landscape of endothelial cells and RA FLS by upregulating transcription of IRF1/5/7/9, IL-1ß, IL-6, and CCL2 through SDC-1 ligation and HIF1α, or mTOR activation. Mechanistically, Syntenin-1 orchestrates RA FLS and endothelial cell invasion via SDC-1 and/or mTOR signaling. In Syntenin-1 reprogrammed endothelial cells, the dynamic expression of metabolic intermediates coincides with escalated glycolysis along with unchanged oxidative factors, AMPK, PGC-1α, citrate, and inactive oxidative phosphorylation. Conversely, RA FLS rewired by Syntenin-1 displayed a modest glycolytic-ATP accompanied by a robust mitochondrial-ATP capacity. The enriched mitochondrial-ATP detected in Syntenin-1 reprogrammed RA FLS was coupled with mitochondrial fusion and fission recapitulated by escalated Mitofusin-2 and DRP1 expression. We found that VEGFR1/2 and Notch1 networks are responsible for the crosstalk between Syntenin-1 rewired endothelial cells and RA FLS, which are also represented in RA explants. Similar to RA explants, morphological and transcriptome studies authenticated the importance of VEGFR1/2, Notch1, RAPTOR, and HIF1α pathways in Syntenin-1 arthritic mice and their obstruction in SDC-1 deficient animals. Consistently, dysregulation of SDC-1, mTOR, and HIF1α negated Syntenin-1 inflammatory phenotype in RA explants, while inhibition of HIF1α impaired synovial angiogenic imprint amplified by Syntenin-1. In conclusion, since the current therapies are ineffective on Syntenin-1 and SDC-1 expression in RA synovial tissue and blood, targeting this pathway and its interconnected metabolic intermediates may provide a novel therapeutic strategy.

A Video Teaching Tool Is Effective for Training Residents in Hip Arthroplasty Templating.

Work hour restrictions imposed on orthopedic surgery residents since the early 2000s have reduced educational opportunities at the workplace and encouraged alternative strategies for teaching outside the clinical setting. Preoperative templating is essential for safe and effective total hip arthroplasty (THA) and is accurate in predicting final implants. We sought to determine the effectiveness of a video tool for teaching orthopedic residents basic THA templating skills. We developed a video-based teaching tool with instructions on proper THA templating techniques. Ten cases were selected for testing, after excluding patients with severe hip deformities and poor-quality radiographs and only retaining those with concordance between templating by the senior authors and implanted components. The study subjects included three postgraduate year 1 (PGY-1), three PGY-2, and three PGY-5 residents, and three adult reconstruction fellows (PGY-6). Templating skills were assessed before and after watching the instructional video. The evaluation included the size and positioning of femoral and acetabular components, as well as the restoration of leg length. Each templating session was repeated twice. Variance was measured to evaluate consistency in measurements. A linear mixed model and F-test were used for statistical analyses. The number of years in training significantly affected performance prior to exposure to the instructional video. Post-exposure, there was a significant improvement in the accuracy of sizing and positioning of acetabular and femoral components for PGY-1, PGY-2, and PGY-5 residents. The results achieved were comparable to PGY-6 examiners, who did not gain substantial performance benefits from the instructional video. Limb length restoration was less affected by experience or exposure to the video. Component positioning and sizing, as well as leg length discrepancy (LLD), showed a significant decrease in variance after the intervention in all study groups. Video learning is reliable in teaching invaluable skills to orthopedic surgery residents without encroaching on work hours. We conceived a concise video to train orthopedic residents to perform THA templating with proper technique and demonstrated its efficiency and reproducibility.

Genomic amplifications identified by circulating tumor DNA analysis guide prognosis in metastatic castration-resistant prostate cancer.

Purpose: Analysis of circulating tumor DNA (ctDNA) in patients with metastatic prostate cancer (mPC) provides an opportunity to identify and monitor genomic alterations during a patient's treatment course. We evaluated whether the presence of specific gene amplifications (GAs) and plasma copy number (PCN) alterations are associated with disease features. Methods: This is a single-institution retrospective study of patients with mPC who underwent ctDNA profiling using Guardant360® (Guardant Health Inc.). This test identifies single nucleotide variants (SNVs) and GAs of select genes by next-generation sequencing. A total of 155 men with mPC were studied. Patients were stratified by GA status. The Kaplan-Meier method and multivariate cox regression models were used to estimate overall survival (OS) or failure-free survival (FFS) from either the date of GA detection or the initiation of systemic therapy. The chi-square test was used to evaluate associations between clinical factors and GAs. Results: The presence of liver and/or lung metastases was associated with GAs of BRAF, CDK6, PI3KCA, and FGFR1. Survival analyses were completed on a subset of 83 patients with metastatic castration-resistant prostate cancer (mCRPC). Median OS was improved in patients with 1 GA compared to patients with ≥2 GAs, whether determined from the date of initial GA(s) detection (14.9 mo vs. 8.9 mo) or date of therapy initiation nearest to GA detection (16.7 mo vs. 9.0 mo). Patients without GAs had not reached median OS. Patients with androgen receptor (AR) GA only were also found to have better median OS compared to patients with AR GA plus at least one other additional GA (19.3 mo vs. 8.9 mo). Patients with PIK3CA GA had significantly lower median OS compared to patients with GAs that did not have a PIK3CA GA (5.9 mo vs. 16.0 mo). In patients with AR and/or MYC GA(s), median OS improved in those with reduced AR or MYC PCN during therapy compared to those without such a reduction (25.1 mo vs. 15.9 mo). Conclusions: The association of select GAs with survival provides an additional tool for assessing mCRPC prognosis and informing management. Serial monitoring of ctDNA GAs is also useful to guide prognosis and therapeutic response.

Revision total hip arthroplasty in younger patients: indications, reasons for failure, and survivorship.

Increasing numbers of total hip arthroplasty (THA) procedures are being performed on younger patients, and the incidence of revision THA in this population is also increasing. The goals of our retrospective study were to survey the surgical indications and reasons for failure and survivorship of revision THA in patients aged < 50 years. We identified 139 cases of revision THA performed over a 6-year period in patients aged < 50 years. The most common reason for revision was aseptic loosening, followed by acetabular liner wear with or without osteolysis. We found an overall 10-year survivorship of 76%. When survivorship was stratified by the indication for revision surgery, revision for wear demonstrated the best 10-year survivorship, while revision for instability or infection exhibited poor survivorship.

Fourth-Generation Ceramic Head Fracture in Dual Mobility Total Hip Arthroplasty: A Case Report.

Introduction: Rare cases of Biolox® delta ceramic head fractures in ceramic-on-polyethylene bearings have been reported in the literature. Virtually none of these catastrophic injuries have been documented in dual mobility constructs. Case Report: We report a case of fourth-generation delta ceramic head fracture 4.5 years after implantation in a dual mobility total hip replacement constructs as a result of a ground-level fall. The patient underwent revision arthroplasty with another delta ceramic dual mobility construct and was able to return to work in custodial services 2 weeks after the revision procedure. Conclusion: In summary, we presented an extremely uncommon case of a fractured fourth generation, Biolox® delta ceramic head in a dual mobility total hip arthroplasty (THA), as a result of a ground-level fall. The patient underwent successful revision surgery to another dual mobility delta ceramic THA. Despite substantial advances in ceramic materials, catastrophic failure of 4th generation ceramic head components can still occur even in dual mobility constructs and require revision arthroplasty surgery.

Surgical epiphysiodesis indications and techniques: update.

PURPOSE OF REVIEW: To present a summary of epiphysiodesis indications and to report most recent advances in the field, along with their clinical relevance. RECENT FINDINGS: Percutaneous epiphysiodesis using transphyseal screws (PETS) and guided growth using eight plates represent the most recent techniques used for hemiepiphysiodesis. SUMMARY: PETS and guided growth have yielded very good results and low rates of complications and are the current standard for the management of angular deformities of the lower extremities in children. Permanent percutaneous epiphysiodesis remains the preferred method for the treatment of limb length discrepancies.

An Update on Multimodal Pain Management After Total Joint Arthroplasty.

➤: Multimodal analgesia has become the standard of care for total joint arthroplasty as it provides superior analgesia with fewer side effects than opioid-only protocols. ➤: Systemic medications, including nonsteroidal anti-inflammatory drugs, acetaminophen, corticosteroids, and gabapentinoids, and local anesthetics via local infiltration analgesia and peripheral nerve blocks, are the foundation of multimodal analgesia in total joint arthroplasty. ➤: Ideally, multimodal analgesia should begin preoperatively and continue throughout the perioperative period and beyond discharge. ➤: There is insufficient evidence to support the routine use of intravenous acetaminophen or liposomal bupivacaine as part of multimodal analgesia protocols.

Optimizing the vertical position of the brace thoracic pad: Apical rib or apical vertebra?

INTRODUCTION: The vertical position of the thoracic pad is a subject of controversy in brace design. Traditional recommendations dictate a maximal force applied at the level of the apical rib, about 2 levels below the apical vertebra. We sought to evaluate the optimal vertical position of the brace thoracic pad using fulcrum bending radiographs. HYPOTHESIS: A lateral force applied at the apical vertebra of a thoracic curve is more efficient at correcting coronal deformity than a force placed the apical rib. PATIENTS AND METHODS: In this prospective study, we recruited patients presenting with adolescent idiopathic scoliosis (AIS) and Risser stage 0-2 over a period of 12 months. Patients with a history of spine or thoracic surgery were excluded. Two fulcrum bending radiographs were performed for each patient: one with the center of the fulcrum placed under the most lateral part of the apical rib and another with the fulcrum centered below the apical vertebra. Cobb angles were measured on each fulcrum radiograph and compared using a paired t test. RESULTS: Fifty-two patients were included, with a mean age of 12.4 years and mean thoracic Cobb angle of 39.4˚. Placing a fulcrum under the apical vertebra reduced the Cobb angle to a mean of 11.5˚, which was significantly lower than a fulcrum placed under the apical rib (14.3˚, p=0.001). This corresponded to a 20% relative loss in the absolute correction angle when placing the fulcrum under the apical rib. The difference between the 2 Cobb angles was not significantly correlated to patient age (p=0.896) or curve apex (p=0.813). DISCUSSION: This is the first clinical study addressing the vertical position of the thoracic pad in braces for AIS. A lateral force applied at the level of the apical vertebra was significantly more efficient at reducing thoracic curve deformities than one applied at the apical rib. Our results provide clinical support to finite element studies that refute traditional recommendations of brace design, advocating for a revision of these guidelines to optimize non-operative treatment of AIS. LEVEL OF EVIDENCE: II, prospective comparative study.

Compartment Syndrome of the Hand: A Rare Sequela of Transradial Cardiac Catheterization.

A 64-year-old man who underwent percutaneous coronary intervention via right radial artery access reported right-hand pain and swelling 2 hours after the procedure. He had developed compartment syndrome of the hand, specifically with muscular compromise of the thenar compartment but with no involvement of the forearm. He underwent emergency right-hand compartment release and carpal tunnel release, followed by an uneventful postoperative course. In addition to our patient's case, we discuss compartment syndrome of the hand and related issues.

Periprosthetic joint infection increases the risk of one-year mortality.

BACKGROUND: Periprosthetic joint infection continues to potentially complicate an otherwise successful joint replacement. The treatment of this infection often requires multiple surgical procedures associated with increased complications and morbidity. This study examined the relationship between periprosthetic joint infection and mortality and aimed to determine the effect of periprosthetic joint infection on mortality and any predictors of mortality in patients with periprosthetic joint infection. METHODS: Four hundred and thirty-six patients with at least one surgical intervention secondary to confirmed periprosthetic joint infection were compared with 2342 patients undergoing revision arthroplasty for aseptic failure. The incidence of mortality at thirty days, ninety days, one year, two years, and five years after surgery was assessed. Multivariate analysis was used to assess periprosthetic joint infection as an independent predictor of mortality. In the periprosthetic joint infection population, variables investigated as potential risk factors for mortality were evaluated. RESULTS: Mortality was significantly greater (p < 0.001) in patients with periprosthetic joint infection compared with those undergoing aseptic revision arthroplasty at ninety days (3.7% versus 0.8%), one year (10.6% versus 2.0%), two years (13.6% versus 3.9%), and five years (25.9% versus 12.9%). After controlling for age, sex, ethnicity, number of procedures, involved joint, body mass index, and Charlson Comorbidity Index, revision arthroplasty for periprosthetic joint infection was associated with a fivefold increase in mortality compared with revision arthroplasty for aseptic failures. In the periprosthetic joint infection population, independent predictors of mortality included increasing age, higher Charlson Comorbidity Index, history of stroke, polymicrobial infections, and cardiac disease. CONCLUSIONS: Although it is well known that periprosthetic joint infection is a devastating complication that severely limits joint function and is consistently difficult to eradicate, surgeons must also be cognizant of the systemic impact of periprosthetic joint infection and its major influence on fatal outcome in patients.