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Vancomycin is often used as antimicrobial prophylaxis for shoulder arthroplasty (SA) either when first generation cephalosporins are contraindicated or colonization with resistant bacteria is anticipated. In general, vancomycin necessitates longer infusion times to mitigate potential side effects. When infusion is started too close to the time of the incision, administration may not be complete during surgery. This study evaluated whether incomplete administration of intravenous (IV) vancomycin prior to shoulder arthroplasty (SA) affects the rate of infectious complications.Between 2000 to 2019, all primary SA types (hemiarthroplasty, anatomic total shoulder arthroplasty, reverse shoulder arthroplasty) performed at a single institution for elective and trauma indications using IV vancomycin as the primary antibiotic prophylaxis and a minimum follow-up of 2 years were identified. The time between the initiation of vancomycin and skin incision was calculated. Complete administration was defined as at least 30 minutes of infusion prior to incision. Demographic characteristics and infectious complications including survival free of prosthetic joint infection (PJI) were generated. Multivariable analyses were conducted to evaluate the association between vancomycin timing and the development of PJI.A total of 461 primary SA were included. Infusion was complete (30 minutes preoperatively) for 163 [35.4%] and incomplete (30 minutes preoperatively) for 298 [64.6%] SA. The incomplete group demonstrated higher rates of any infectious complication (8% vs. 2.3%; P = .005), PJI (5.5% vs. 1%; P = .004), and reoperation inclusive of revision due to infectious complications (4.9% vs. 1%; P = .009). Survivorship free of PJI was worse in SA with incomplete compared to those with complete vancomycin administration. Survival rates for incomplete and complete administration were 97.6% and 99.3% at 1 month, 95.7% and 99.0% at 2 years, 95.1% and 99.0% at 5 years, and 93.9% and 99.0% at 20 years, respectively (P = .006). Multivariable analyses confirmed that incomplete vancomycin administration was an independent risk factor for PJI compared with complete administration (hazard ratio [HR], 4.22 [95% confidence interval (CI), 1.12 to 15.90]; P = .033), even when other independent predictors of PJI (age, male sex, prior surgery, MRSA colonization, and follow-up) were considered.When vancomycin is the primary prophylactic agent used at the time of primary shoulder arthroplasty, incomplete administration (infusion to incision time under 30 minutes) seems to adversely increase the rates of infectious complications and PJI. Prophylaxis protocols should ensure that complete vancomycin administration is achieved to minimize infection after SA.

Background: Healthcare systems are shifting toward “patient-centered” care often without assessing the values important to patients. Analogously, the interests of the patient may be disparate with physician interests, as pay-for-performance models become common. The purpose of the study was to determine which medical preferences are essential for patients during their surgical care. Methods: This prospective, observational study surveyed 102 patients who had undergone a primary knee replacement and/or hip replacement surgery about hypothetical scenarios regarding their surgical experience. Data analysis included categorical variables presented as a number and percent, while continuous variables presented as mean and standard deviation. Statistical analysis for anticoagulation data included the Pearson chi-square test and one-way ANOVA test. Results: A large majority, 73 patients (72%), would not pay to have a four-centimeter or smaller incision. The remaining 29 patients (28%) would prefer to have a four-centimeter or smaller incision and would pay a mean of $1,328 ± 1,629 for that day. A significant number of patients preferred not to use anticoagulation (p = 0.019); however, the value attributed to avoiding a specific method of anticoagulation was found not to be significant (p = 0.507). Conclusions: The study determined the metrics prioritized by hospitals and surgeons are not important to the majority of patients when they evaluate their own care. These disconnects in the entitlements patients expect and receive can be solved by including patients in discussions with physicians and hospital systems.

Purpose: The aim of the study was to determine the restoration of hip biomechanics through lateral offset, leg length, and acetabular component position when comparing non-arthroplasty surgeons (NAS) to elective arthroplasty surgeons (EAS). Methods: 131 patients, with a femoral neck fracture treated with a THA by 7 EAS and 20 NAS, were retrospectively reviewed. 2 blinded observers measured leg-length discrepancy, femoral offset, and acetabular component position. Multivariate logistic regression models examined the association between the surgeon groups and restoration of lateral femoral, acetabular offset, leg length discrepancy, acetabular anteversion, acetabular position, and component size, while adjusting for surgical approach and spinal pathology. Results: NAS under-restored 4.8 mm of lateral femoral offset (43.9 ± 8.7 mm) after THA when compared to the uninjured side (48.7 ± 7.1 mm, p = 0.044). NAS were at risk for under-restoring lateral femoral offset when compared to EAS ( p = 0.040). There was no association between lateral acetabular offset, leg length, acetabular position, or component size and surgeon type. Conclusions: Lateral femoral offset is at risk for under-restoration after THA for femoral neck fractures, when performed by surgeons that do not regularly perform elective THA. This indicates that lateral femoral offset is an under-appreciated contributor to hip instability when performing THA for a femoral neck fracture. Lateral femoral offset deserves as much attention and awareness as acetabular component position since a secondary analysis of our data reveal that preoperative templating and intraoperative imaging did not prevent under-restoration.

Adipose-derived stem cells (ASCs) can be isolated in large quantities from the lipoaspirates of patients. Furthermore, the therapeutic potential of ASCs is vast, with their ability to differentiate into osteogenic, chondrogenic, and adipogenic phenotypes. This chapter focuses on the genetic modifications of ASCs to differentiate into osteogenic cells for bone regeneration. The role of important signaling pathways such as bone morphogenic protein (BMP), hedgehog (HH), and wingless (WNT) are discussed in the context of osteogenesis. Furthermore, the exogenous application of signaling pathway proteins is explored to understand the commitment of stem cells toward osteoblastic differentiation in the setting of cell cultures. The advantages and disadvantages of genetic alteration technologies, including electroporation, viral transduction, minicircles, CRISPR, and nanoparticles, are analyzed to determine methods of promoting osteogenesis by targeting specific genes within the stem cells. Altering the genetic landscape of the innate ASC genome through genetic technologies can establish standardized protocols to safely develop cell-based therapeutics for bone regeneration. Finally, the chapter will highlight ongoing applications of genetically altered ASCs for bone regeneration in patients to establish the current clinical care landscape.

Intermittent pneumatic compression is part of the current standard of care model for preventing venous thromboembolic events (VTE) after total joint arthroplasty. Pneumatic motors limit the rate of inflation resulting in bulky devices with uncomfortable sleeves that inhibited patient compliance and mobility. Nonpneumatic mechanical devices are an alternative for providing mobile, graded, intermittent, sequential, rapid, and monitorable compression posthospitalization. Fifteen healthy volunteers underwent mechanical compression using the Cirvo (Radial Medical, Mountain View, CA) as well as pneumatic compression with four commercially available systems (VenaFlow Elite, Kendall SCD Compression System, ActiveCare DVT, Vasculaire Compression System) and manual calf compression. Peak flow velocity (PFV) was measured by ultrasound of the femoral vein during compression and at baseline. Mechanical compression for 1 second resulted in a significant increase in femoral venous PFV to 107.8 ± 38.2 cm/s from 17.1 ± 4.7 cm/s at baseline (P < .001). The change in femoral venous PFV with mechanical compression for 1 second (90.7 ± 34.9 cm/s) was not statistically different from pneumatic compression from VenaFlow system (106.0 ± 35.6 cm/s, P = .124) and statistically lower than manual calf compression (115.5 ± 26.8 cm/s, P = .015). Pneumatic compression from the VenaFlow system produced the largest change in femoral venous PFV of all commercial pneumatic systems tested. Mechanical compression replicates or exceeds femoral venous PFV available from currently available intermittent pneumatic compression.

Background Piriformis-sparing approaches to the hip allow surgeons to avoid releasing the piriformis tendon during total hip arthroplasty; however, the consequences of retracting an intact piriformis tendon during such an approach remain ill-defined. The present study aimed to determine the upper limit of force that can be applied during retraction of the piriformis tendon to expose the hip, and to quantify the resultant damage to the piriformis musculotendinous complex. Methods A patent-pending instrumented retractor was designed to record the applied force, duration, and angle of retraction during a piriformis-sparing posterior approach to the hip. In addition to the data collected with use of the instrumented retractor, damage to the piriformis muscle and tendon was quantified by a blinded observer. Results There was no damage to the piriformis tendon in 22 (96%) of 23 hips during piriformis retraction for visualization of the hip capsule; however, there was complete or partial damage to the piriformis muscle at the sacral origin, belly, or musculotendinous junction (i.e., outside the surgical field) noted in 21 (91%) of 23 hips. The mean peak force to failure of the piriformis muscle was exceedingly small (29.0 ± 9.4 N; range, 10.1 to 44.9 N). Conclusions The mean peak force applied to the piriformis retractor is much less than the force required for several common daily activities, such as opening a door or crushing an empty aluminum can. Soft-tissue damage that occurs outside the surgical field during the retraction of unreleased muscles, like the piriformis muscle, is common and remains an uncontrolled surgical variable. This inadvertent soft-tissue damage is not routinely accounted for when accessing the invasiveness of a procedure. Hence, it is no longer adequate to define a minimally invasive surgical procedure simply as an approach that involves the limited release of anatomical structures. Clinical relevance The use of instrumented retractors may redefine surgical invasiveness by providing data that could alter our understanding of the soft-tissue damage caused by retraction and open the possibility of robot-assisted or damage-limiting retractor systems.

Background Prior data demonstrate significant heterogeneity regarding coronary artery disease risk factors and outcomes among Asians in the United States, but no studies have yet examined coronary artery disease treatment patterns or outcomes among disaggregated Asian American subgroups. Methods and Results From a total of 772 882 patients with known race/ethnicity and sex who received care from a mixed‐payer healthcare organization in Northern California between 2006 and 2015, a retrospective analysis was conducted on 6667 adults with coronary artery disease. Logistic regression was used to examine medical and procedural therapies and outcomes by race/ethnicity, with adjustment for age, sex, income, and baseline comorbidities. Compared with non‐Hispanic whites, Chinese were more likely to undergo stenting (50.9% versus 60.8%, odds ratio [ OR ] 1.39 [95% CI , 1.04–1.87], p=0.005), whereas Filipinos were more likely to receive bypass surgery (6.9% versus 20.5%, OR 2.65 [95% CI , 1.75–4.01], P OR s 1.86 [95% CI , 1.13–3.04], 1.86 [95% CI , 1.01–3.44], and 4.37 [95% CI , 1.02–18.67], respectively, P OR s 1.49 [95% CI , 1.02–2.19] and 1.68 [95% CI , 1.21–2.34], respectively, P Conclusions Disaggregation of Asian Americans with coronary artery disease into individual racial/ethnic subgroups reveals significant variability in treatment patterns and outcomes. Further investigation into these differences may expose important opportunities to mitigate disparities and improve quality of care in this diverse population.