Tibial bone loss.

Critical bone loss after open fractures, while relatively uncommon, occurs most frequently in high-energy injuries. Fractures of the tibia account for the majority of open fractures with significant bone loss. A number of different surgical strategies exist for treatment of tibial bone loss, all with different advantages and disadvantages. Care should be taken by the surgeon to review appropriate indications and all relevant evidence before selecting a strategy.

Nanoparticle ultrasonication outperforms conventional irrigation solutions in eradicating Staphylococcus aureus biofilm from titanium surfaces: an in vitro study.

PURPOSE: Bacterial biofilms create a challenge in the treatment of prosthetic joint infection (PJI), and failure to eradicate biofilms is often implicated in the high rates of recurrence. In this study, we aimed to compare the effectiveness of a novel nanoparticle ultrasonication technology on Staphylococcus aureus biofilm eradication compared to commonly used orthopedic irrigation solutions. METHODS: Twenty-four sterile, titanium alloy discs were inoculated with a standardized concentration of methicillin-resistant S. aureus and cultured for seven days to allow for biofilm formation. Discs were then treated with either ultrasonicated nanoparticle therapy or irrigation with chlorhexidine gluconate, povidone-iodine or normal saline. The remaining bacteria on each surface was subsequently plated for colony-forming units of S. aureus. Bacterial eradication was reported as a decrease in CFUs relative to the control group. Mann-Whitney U tests were used to compare between groups. RESULTS: Treatment with ultrasonicated nanoparticles resulted in a significant mean decrease in CFUs of 99.3% compared to controls (p < 0.0001). Irrigation with povidone-iodine also resulted in a significant 77.5% reduction in CFUs compared to controls (p < 0.0001). Comparisons between ultrasonicated nanoparticles and povidone-iodine demonstrated a significantly higher reduction in bacterial CFUs in the nanoparticle group (p < 0.0001). CONCLUSION: Ultrasonicated nanoparticle were superior to commonly used bactericidal irrigation solutions in the eradication of S. aureus from a titanium surface. Future clinical studies are warranted to evaluate this ultrsonication technology in the treatment of PJI.

Stiffness After Total Knee Arthroplasty A Review.

Postoperative stiffness is a challenging problem in the setting of primary total knee arthroplasty. There remains a relatively high prevalence of patients suffering from this condition, and it can lead to unsatisfactory outcomes and need for revision surgery as well as a large financial burden on the health care system. There are a number of factors that predispose patients to developing arthrofibrosis, including patient-specific factors and intraoperative and postoperative considerations. Arthrofibrosis can be treated effectively in the early stages with manipulation under anesthesia with or without lysis of adhesions, however, those who fail to respond to these interventions may require revision surgery, which generally has poorer outcomes when performed for this indication. Current research is focused on understanding the pathologic cascade of arthrofibrosis and novel targeted therapeutics that may decrease stiffness in these patients and improve outcomes.

Revision rate following unipolar versus bipolar hemiarthroplasty.

INTRODUCTION: There has been much debate on use of bipolar or unipolar femoral heads in hemiarthroplasty for the treatment of femoral neck fractures. The outcome of these implants should be studied in the America Joint Replacement Registry (AJRR). METHODS: All primary femoral neck fractures treated with hemiarthroplasty between January 2012 and June 2020 were searched in the AJRR. All cause-revision of unipolar and bipolar hemiarthroplasty and reasons for revision were assessed for these patients until June of 2023. RESULTS: There were no differences in number and reason for all cause revisions between unipolar and bipolar hemiarthroplasty (p = 0.41). Bipolar hemiarthroplasty had more revisons at 6 months postoperatively (p = 0.0281), but unipolar hemiarthroplasty had more revisions between 2 and 3 years (p = 0.0003), and after 3-years (p = 0.0085), as analysed with a Cox model. Patients with older age (HR = 0.999; 95% CI, 0.998-0.999; p = 0.0006) and higher Charlson Comorbidity Index (HR = 0.996; 95% CI, 0.992- 0.999; p = 0.0192) had a significant increase in revision risk. CONCLUSIONS: We suggest that surgeons should consider using bipolar prosthesis when performing hemiarthroplasty for femoral neck fracture in patients expected to live >2 years post injury.

Two-Year Outcomes of Novel Dual-Mobility Implant in Primary Total Hip Arthroplasty.

Introduction: Dual-mobility (DM) implants for total hip arthroplasty (THA) have gained popularity due to their potential to reduce hip instability and dislocation events that may lead to revision surgery. These implants consist of a femoral head articulated within a polyethylene liner, which articulates within an outer acetabular shell, creating a dual-bearing surface. Our study aimed to report our observations on the survivorship of a novel DM implant for primary total hip arthroplasty at two years. Methods: We conducted a retrospective, multicenter study to assess the clinical outcomes of patients undergoing a THA with a novel DM implant (OR3O acetabular system™, Smith & Nephew, Inc., Memphis, TN) from January 2020 to September 2021. Patient demographics, surgical information, and survivorship data were collected from medical records for patients with a minimum of two years of follow-up. Primary outcomes included overall implant survivorship at two years as well as aseptic survivorship, revision rates of the DM acetabular shell, and average time to revision. Patient-reported outcomes were collected in the form of HOOS JR. Results: A total of 250 hips in 245 patients had a minimum two-year follow-up. Primary osteoarthritis (80%) was the most common indication for index THA. The average aseptic survivorship of the DM acetabular components at two years for the cohort was 98.4% and survivorship of the acetabular implants overall was 97.6%. There were a total of four (1.6%) aseptic revisions of the DM acetabular component. Reasons for aseptic acetabular revision included one case of instability, one intraprosthetic dislocation, one periprosthetic acetabular fracture, and one malpositioned acetabular cup resulting in impingement. The mean time of follow-up was 893.9 days. Eighty-seven patients had preoperative and two-year HOOS JR available. HOOS JR improved by an average of 38.5 points. Conclusion: This novel DM acetabular implant demonstrates excellent survivorship at two years follow-up with low rates of instability and intraprosthetic dislocation and no episodes of metal-on-metal corrosion. Use of the DM implant demonstrated clinically relevant improvements in patient-reported outcomes at two years.

Regional Trends in Unicondylar and Patellofemoral Knee Arthroplasty: An Analysis of the American Joint Replacement Registry.

BACKGROUND: As the popularity of unicondylar knee arthroplasty (UKA) and patellofemoral arthroplasty (PFA) have expanded, more patients who have limited arthritis are undergoing partial knee arthroplasty. No studies have evaluated if any regional differences in the United States (U.S.) exist between partial versus total knee arthroplasty (TKA). The purpose of this study was to utilize the American Joint Replacement Registry to evaluate regional differences in UKA, PFA, and TKA. METHODS: The American Joint Replacement Registry was queried for all TKA, PFA, and UKA procedures between 2012 and 2021. Surgical volume was compared between the Midwest (MW), Northeast (NE), South, and West (W) regions. Trends were compared using multivariate logistic regression analyses and least squared mean logistic regression models. RESULTS: Since 2012, there has been a steady increase in the amount of UKAs performed across the U.S., except during the COVID-19 pandemic when numbers decreased. Logistic regression analyses demonstrated a higher likelihood of receiving a UKA compared to TKA in the NE compared to other regions, and higher likelihood of receiving a PFA in the NE and W compared to other regions over the study period. Other factors that increased the likelihood of having a UKA nationally were men, the procedure being performed at a teaching hospital, and having surgery in urban areas. Patients were more likely to have a PFA in the NE compared to the S and MW, and higher odds in the South and W compared to the MW, with rates of PFA consistently lower in the MW compared to other regions. CONCLUSIONS: Patients were more likely to have a UKA in the NE compared to other regions of the country. Patients had higher odds of having a PFA in the NE and W regions relative to the MW. Men had higher odds of having either UKA or PFA than women across the nation.

The Effects of Autologous Fat Transfer in an In Vitro Model of Basal Joint Osteoarthritis.

PURPOSE: Basal joint osteoarthritis (OA) is a highly prevalent and debilitating condition. Recent clinical evidence suggests that autologous fat transfer (AFT) may be a promising, minimally invasive treatment for this condition. However, the mechanism of action is not fully understood. It is theorized that AFT reduces inflammation in the joint, functions to regenerate cartilage, or acts as a mechanical buffer. The purpose of this study was to better understand the underlying mechanism of AFT using an in vitro model. We hypothesize that the addition of stromal vascular fraction (SVF) cells will cause a reduction in markers of inflammation. METHODS: Articular chondrocytes were expanded in culture. Liposuction samples were collected from human subjects and processed similarly to AFT protocols to isolate SVF rich in adipose-derived stem cells. A control group was treated with standard growth media, and a positive control group (OA group) was treated with inflammatory cytokines. To mimic AFT, experimental groups received inflammatory cytokines and either a low or high dose of SVF. Expression of relevant genes was measured, including interleukin (IL)-1ß, IL-1 receptor antagonist, and matrix metalloproteinases (MMP). RESULTS: Compared to the OA group, significant decreases in IL-1ß, MMP3, and MMP13 expression on treatment day 3 were found in the high-dose SVF group, while MMP13 expression was also significantly decreased in the low-dose SVF group on day 3. CONCLUSIONS: In this study, we found that SVF treatment reduced expression of IL-1ß, MMP3, and MMP13 in an in vitro model of OA. These results suggest that an anti-inflammatory mechanism may be responsible for the clinical effects seen with AFT in the treatment of basal joint OA. CLINICAL RELEVANCE: An anti-inflammatory mechanism may be responsible for the clinical benefits seen with AFT for basal joint arthritis.

Liposomal bupivacaine does not decrease postoperative opioid use or length of hospital stay in patients undergoing anterior cervical discectomy and fusion.

Background: Despite its widespread use, definitive data demonstrating the efficacy of liposomal bupivacaine (LB) is limited especially in patients undergoing anterior cervical discectomy and fusion (ACDF). Therefore, this investigation examined whether ACDF patients who received intra-operative LB (LB cohort) exhibited decreased post-operative opioid use and lengths of hospital stay (LOS) compared to ACDF patients who did not receive intra-operative LB (controls). Methods: Eighty-two patients who underwent primary ACDF by a single surgeon from 2016 to 2019 were identified from an institutional database. Fifty-nine patients received intra-operative LB while twenty-three did not. Patient characteristics, medical comorbidities, complications, post-operative opioid consumption, and LOS data were collected. Results: The LB cohort did not require fewer opioids on post-operative day (POD) 0, POD1, POD2, or throughout the hospital course after normalizing by LOS (total per LOS). The number of cervical vertebrae involved in surgery, but not LB use, predicted opioid consumption on POD0, POD1, and total per LOS. For every vertebral level involved, 242 additional morphine milligram equivalents (MME) were consumed on POD0, 266 additional MME were utilized on POD1, and 130 additional MME were consumed in total per LOS. Conclusions: ACDF patients who received intra-operative LB did not require fewer post-operative opioids or exhibit a decreased LOS compared to controls. Patients whose procedures involved a greater number of cervical vertebrae were associated with greater opioid consumption on POD0, POD1, and total per LOS. ACDF patients, especially those who had a high number of vertebrae involved, may require alternative analgesia to LB.

The impact of confirmed coronavirus disease 2019 (COVID-19) infection on ambulatory procedures and associated delays in care for asymptomatic patients.

BACKGROUND: Since the reopening of ambulatory centers, minimal data has been reported regarding positive tests among patients undergoing ambulatory procedures, associated delays in care, and outcomes of patients previously positive for coronavirus disease 2019. METHODS: A retrospective observational case series of ambulatory procedures was performed. Records since the reopening of ambulatory centers in New York were searched for patients with positive coronavirus disease 2019 nasal swab results who underwent ambulatory procedures. Chart reviews were conducted to determine coronavirus disease history and hospitalizations, demographic information, procedure details, and 30-day admissions. RESULTS: A total of 3,762 patients underwent ambulatory procedures. Of those, 53 were previously diagnosed with coronavirus disease 2019 but recovered and tested negative at preprocedural testing. Of the 3,709 asymptomatic patients, 37 (1.00%) tested positive during preprocedural testing; 21 patients had their procedures delayed on average 28.6 days until testing negative, while 16 had their procedures performed before testing negative owing to the time sensitivity of the procedure. There were no major complications or 30-day admissions in any of these asymptomatic patients. Three patients tested positive for coronavirus disease after having an ambulatory procedure. CONCLUSION: Positive tests in asymptomatic patients led to procedure delays of 28.6 days. No patients who underwent ambulatory procedures after a positive coronavirus disease 2019 test had any coronavirus disease-related complications, regardless of whether or not the procedure was delayed until testing negative. Three patients tested positive for coronavirus disease 2019 after having an ambulatory procedure; however, at an average of 19.7 days after, these cases were likely community acquired making the rate of nosocomial infection negligible.

Biomechanical and geometric characterization of peroneus longus allografts with respect to age.

BACKGROUND: Anterior cruciate ligament injuries are among the most common injuries in high impact sports, and reconstruction is the standard surgical procedure for these ruptures. Reconstructions are often performed using allografts rather than autografts on a case-by-case basis. Controversy exists as to whether or not age of donor tissue plays a factor in the mechanical properties of allografts. METHODS: 38 peroneus longus (PL) tendons were prepared using the two-strand graft technique and then subjected to a cyclic loading test regimen of 1000 cycles to determine material properties. Specimens were grouped based on age to ascertain whether donor age affects the material properties of PL tendons. FINDINGS: Secant modulus of the first cycle was determined to be 150.43 (SD 40.24) MPa. The average magnitude of the dynamic modulus was determined to be 82.81 (SD 24.65) MPa. Specimens were grouped into three distinct groups for analysis (x < 40 yo, 40 yo ≤ x < 60 yo, 60 yo < x). INTERPRETATION: The need for using intrinsic material properties is highlighted. There is no significant difference in any intrinsic material property with respect to age or the fatigue of the tendon as the cycle count increases. Conversely, the measured stiffness of a tendon decreased as function of age with a large effect size. Based on analysis of graft geometries, it was determined that PL tendons become significantly more slender with increased age which result in the observed decrease in stiffness.

Large-scale identification of human cerebrovascular proteins: Inter-tissue and intracerebral vascular protein diversity.

The human cerebrovascular system is responsible for regulating demand-dependent perfusion and maintaining the blood-brain barrier (BBB). In addition, defects in the human cerebrovasculature lead to stroke, intracerebral hemorrhage, vascular malformations, and vascular cognitive impairment. The objective of this study was to discover new proteins of the human cerebrovascular system using expression data from the Human Protein Atlas, a large-scale project which allows public access to immunohistochemical analysis of human tissues. We screened 20,158 proteins in the HPA and identified 346 expression patterns correlating to blood vessels in human brain. Independent experiments showed that 51/52 of these distributions could be experimentally replicated across different brain samples. Some proteins (40%) demonstrated endothelial cell (EC)-enriched expression, while others were expressed primarily in vascular smooth muscle cells (VSMC; 18%); 39% of these proteins were expressed in both cell types. Most brain EC markers were tissue oligospecific; that is, they were expressed in endothelia in an average of 4.8 out of 9 organs examined. Although most markers expressed in endothelial cells of the brain were present in all cerebral capillaries, a significant number (21%) were expressed only in a fraction of brain capillaries within each brain sample. Among proteins found in cerebral VSMC, virtually all were also expressed in peripheral VSMC and in non-vascular smooth muscle cells (SMC). Only one was potentially brain specific: VHL (Von Hippel-Lindau tumor suppressor). HRC (histidine rich calcium binding protein) and VHL were restricted to VSMC and not found in non-vascular tissues such as uterus or gut. In conclusion, we define a set of brain vascular proteins that could be relevant to understanding the unique physiology and pathophysiology of the human cerebrovasculature. This set of proteins defines inter-organ molecular differences in the vasculature and confirms the broad heterogeneity of vascular cells within the brain.