Nonmarinum, Nontuberculous Mycobacterial Infections of the Upper Extremity: A Multi-Institutional Descriptive Report.

PURPOSE: We analyzed patient demographic factors involved in the development of nonmarinum, nontuberculous mycobacterial infections (NTMI) involving the upper extremity, and assessed diagnostic and prognostic values of commonly used preoperative laboratory and imaging studies, as well as factors related to recurrence of disease and patient outcomes. METHODS: Patients from 2 academic, tertiary facilities with culture-proven, nonmarinum NTMI involving the upper extremity were reviewed. Patient-related factors and clinical outcomes were extracted. The analysis was based on pathogen identification (rapid- vs slow-growing subspecies) and immune status. RESULTS: Our 76 patients had a mean age of 59 years, and 65% were male. Forty-eight percent reported an injury, and hands were frequently involved (58%). Forty-one percent were immunosuppressed (19% organ transplant recipients). The mean symptom duration prior to presentation was 203 days. The culture identification took a mean of 33 days, with 25 different species identified (subcategorized as rapid or slow growers). Seventy-seven percent had solitary lesions, with a cutaneous or subcutaneous location most common. Immunosuppressed patients were treated longer with antibiotics (243 vs 155 days in immunocompetent patients) and experienced higher rates of side effects, complications, and recurrence. All patients underwent debridement to control infection, including 4 individuals who required amputations. One-third experienced complications and/or recurrence, regardless of the organism type. CONCLUSIONS: Upper-extremity nonmarinum NTMI is often misdiagnosed, causing management delays. Early consideration in differential diagnoses of chronic, painful swelling, nodular or inflammatory lesions, or septic arthritis is crucial. Tissue biopsy with specimens for histopathology and microbiological analysis (mycobacterial smear, cultures, and broad range polymerase chain reaction) and early involvement with an infectious disease specialist are recommended. Empiric antibiotic therapy is not standard. Debridement and prolonged, directed combination antimicrobial therapy is required; however, adverse reactions are commonly encountered. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic IV.

Getting paid less for more: shoulder arthroplasty incidence and reimbursement within Medicare from 2000 to 2019.

BACKGROUND: Shoulder arthroplasty has grown in popularity in the past 2 decades, especially following US Food and Drug Administration approval of reverse total shoulder arthroplasty (TSA) in 2003. Studies have shown that Medicare reimbursement for a variety of orthopedic procedures has decreased significantly over the past 2 decades. No study has evaluated this trend in the setting of shoulder arthroplasty, however. The purpose of this study was to assess true reimbursement trends in primary and revision shoulder arthroplasty since 2000. METHODS: Information was collected from the publicly available Medicare Part B National Summary Data Files for the period of 2000 to 2019. Data from Current Procedural Terminology codes 23470 (shoulder hemiarthroplasty), 23472 (TSA), 23473 (single-component revision shoulder arthroplasty), and 23474 (both-component revision shoulder arthroplasty) were analyzed. Reimbursement amounts were adjusted for inflation to May 2021 dollars. RESULTS: From 2000 to 2019, the number of shoulder hemiarthroplasty procedures billed to Medicare decreased 70% (from 5847 to 1750) whereas the number of TSA procedures increased 1527% (from 4044 to 65,477). During the same period, per-procedure Medicare reimbursement for hemiarthroplasty decreased 35% (from $1545.71 to $1003.43) after adjustment for inflation to 2021 dollars. Similarly, TSA reimbursement decreased 22% (from $1600.98 to $1248.76) after adjustment for inflation. For revision procedures, the number of single- and both-component revisions billed to Medicare increased 381% (from 344 to 1655) and 1331% (from 220 to 3147), respectively. Adjusted reimbursement per procedure decreased 36% (from $1931.62 to $1244.49) and 37% (from $2293.08 to $1449.43), respectively. CONCLUSION: This study shows an increase in the annual volume of primary and revision shoulder arthroplasty procedures from 2000 to 2019. During the same period (2000-2019), true Medicare reimbursement to physicians for TSA decreased when adjusted for inflation. This study provides data that may be useful for surgeons, hospitals, and policy makers to maintain access to quality shoulder arthroplasty care moving forward.

Formative Feedback with In-Class Question Bank Utilization Improves Resident Satisfaction with General Surgery Didactics.

BACKGROUND: Formative feedback provides low-stakes opportunities for educational improvement. To enrich our basic science didactics, formative feedback measures were incorporated into our didactics using mobile devices. MATERIALS AND METHODS: Lecture changes included institutional paid access to a commercial question bank, a 5-item in-class pre-didactic quiz curated from the question bank and taken on the resident's mobile device, and group discussion of quiz topics. An anonymous survey was sent to participating residents. RESULTS: Overall response rate was 71% among residents. All reported that the new lecture format was a valuable addition to the basic science curriculum (100% Agree/Strongly Agree), and formative assessments provided valuable feedback about the progress of their learning (Strongly Agree = 42%, Agree =58%). All residents reported that in-class use of their mobile device for quizzes was convenient, with majority (84%) preferring it over paper printouts. Residents were more motivated to study before lecture (Strongly Agree = 42%, Agree =42%), with majority also reporting the new format helped identify weaknesses in their knowledgebase (Strongly Agree = 58%, Agree =33%). While majority of residents agreed that quizzes motivated them to study more after lecture, a large portion disagreed (42%). Majority of senior residents reported that the process of composing quizzes prior to lecture enriched their own learning (57%) and helped them find gaps in their knowledge (71%). CONCLUSION: Incorporating a commercial question bank within didactics gives general surgery residents formative feedback and encourages learning outside the classroom, leading to improved satisfaction with basic science didactics.

Comparison of Two-level Cervical Disc Replacement Versus Two-level Anterior Cervical Discectomy and Fusion in the Outpatient Setting.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: The aim of this study was to evaluate the safety of two-level cervical disc replacement (CDR) in the outpatient setting. SUMMARY OF BACKGROUND DATA: Despite growing interest in CDR, limited data exist evaluating the safety of two-level CDR in the outpatient setting. METHODS: The National Surgical Quality Improvement Program (NSQIP) database was queried for all two-level anterior cervical discectomy and fusion (ACDF) and CDR procedures between 2015 and 2018. Demographics, comorbidities, and 30-day postoperative complication rates of outpatient two-level CDR were compared to those of inpatient two-level CDR and outpatient two-level ACDF. Radiographic data are not available in the NSQIP. RESULTS: A total of 403 outpatient CDRs were compared to 408 inpatient CDRs and 4134 outpatient ACDFs. Outpatient CDR patients were older and more likely to have pulmonary comorbidities compared to inpatient CDR (P < 0.03). Outpatient CDR patients were less likely to have an American Society of Anesthesiologists class ≥2 and have hypertension compared to outpatient ACDF patients (P < 0.0001). Outpatient CDR had a lower 30-day readmission rate (0.5% vs. 2.5%, P = 0.02) and lower 30-day reoperation rate (0% vs. 1%, P = 0.047) compared to inpatient CDR. Outpatient CDR had a lower readmission rate (0.5% vs. 2.1%, P = 0.03) compared to outpatient ACDF, but there was no difference in reoperation rates between the two procedures (0% vs. 0.8%, P = 0.07). Outpatient CDR had an overall complication rate of 0.2%, inpatient CDR had a complication rate of 0.9%, and outpatient ACDF had a complication rate of 1.3%. These differences were not significant. CONCLUSION: To our knowledge, this is the largest multicenter study examining the safety of two-level outpatient CDR procedures. Outpatient two-level CDR was associated with similarly safe outcomes when compared to inpatient two-level CDR and outpatient two-level ACDF. This suggests that two-level CDR can be performed safely in the outpatient setting.Level of Evidence: 3.

Robotic Harvest of a Rectus Abdominis Muscle Flap After Abdominoperineal Resection.

INTRODUCTION: As multidisciplinary treatment modalities for rectal cancer continue to evolve, neoadjuvant chemoradiation then surgical resection is a common approach. Robotic-assisted abdominoperineal resection is becoming more prevalent in part because of better visualization and instrument mobility within the pelvis. After abdominoperineal resection, postoperative perineal wound complications remain a significant risk. Pelvic reconstruction lowers this risk, and a pedicled rectus abdominis muscle flap is frequently used to achieve this. Traditional flap harvest requires laparotomy, resulting in violation of both rectus sheaths and a large midline scar. Robotic harvest of the rectus abdominis muscle for pelvic reconstruction after abdominoperineal resection is a novel approach with foreseeable benefits. TECHNIQUE: After completion of abdominoperineal resection, 2 additional trocars are inserted in the lateral abdomen, and the robot is reoriented toward the posterior abdominal wall. The peritoneum and posterior rectus sheath are incised, and dissection is carried superiorly and inferiorly in a sagittal plane to reveal the rectus abdominis muscle. The muscle body is separated from the anterior rectus sheath. Once the inferior epigastric artery is identified, the superior pole of the muscle is transected. Continued lateral dissection ensures flap mobility for placement within the pelvis. After obtaining proper reach, the robot is undocked, and the flap is sutured in place through the perineal defect. RESULTS: After trocar placement and robot repositioning, both the colorectal and plastic surgeons trade places at the console. Robotic flap harvest precludes the need for laparotomy. The anterior rectus sheath remains unviolated and the patient avoids an additional midline scar. The aforementioned benefits of robot-assisted abdominoperineal resection, namely increased visualization and maneuverability, were also found applicable when robotically harvesting this flap. CONCLUSIONS: This technique exemplifies an additional minimally invasive technique for patients pursuing abdominoperineal resection. With knowledge of this novel approach, surgeons can better tailor their operations to benefit the patient.

Networks of HIV-1 Envelope Glycans Maintain Antibody Epitopes in the Face of Glycan Additions and Deletions.

Numerous broadly neutralizing antibodies (bnAbs) have been identified that target the glycans of the HIV-1 envelope spike. Neutralization breadth is notable given that glycan processing can be substantially influenced by the presence or absence of neighboring glycans. Here, using a stabilized recombinant envelope trimer, we investigate the degree to which mutations in the glycan network surrounding an epitope impact the fine glycan processing of antibody targets. Using cryo-electron microscopy and site-specific glycan analysis, we reveal the importance of glycans in the formation of the 2G12 bnAb epitope and show that the epitope is only subtly impacted by variations in the glycan network. In contrast, we show that the PG9 and PG16 glycan-based epitopes at the trimer apex are dependent on the presence of the highly conserved surrounding glycans. Glycan networks underpin the conservation of bnAb epitopes and are an important parameter in immunogen design.

Autologous Antibody Responses to an HIV Envelope Glycan Hole Are Not Easily Broadened in Rabbits.

Extensive studies with subtype A BG505-derived HIV envelope glycoprotein (Env) immunogens have revealed that the dominant autologous neutralizing epitope in rabbits is located in an exposed region of the heavily glycosylated trimer that lacks potential N-linked glycosylation sites at positions 230, 241, and 289. The Env derived from B41, a subtype B virus, shares a glycan hole centered on positions 230 and 289. To test whether broader neutralization to the common glycan hole can be achieved, we immunized rabbits with B41 SOSIP (gp120-gp41 disulfide [SOS] with an isoleucine-to-proline mutation [IP] in gp41) alone, as well as B41 and BG505 coimmunization. We isolated autologous neutralizing antibodies (nAbs) and described their structure in complex with the B41 Env. Our data suggest that distinct autologous nAb lineages are induced by BG505 and B41 immunogens, even when both were administered together. In contrast to previously described BG505 glycan hole antibodies, the B41-specific nAbs accommodate the >97% conserved N241 glycan, which is present in B41. Single-particle cryo-electron microscopy studies confirmed that B41- and BG505-specific nAbs bind to overlapping glycan hole epitopes. We then used our high-resolution data to guide mutations in the BG505 glycan hole epitope in an attempt to broaden the reactivity of a B41-specific nAb, but we recovered only partial binding. Our data demonstrate that the lack of cross-reactivity in glycan hole antibodies is due to amino acid differences within the epitope, and our attempts to rationally design cross-reactive trimers resulted in only limited success. Thus, even for the immunodominant glycan hole shared between BG505 and B41, the prospect of designing prime-boost immunogens remains difficult.IMPORTANCE A glycan hole is one of the most dominant autologous neutralizing epitopes targeted on BG505 and B41 SOSIP trimer-immunized rabbits. Our high-resolution cryo-electron microscopy (cryoEM) studies of B41 in complex with a B41-specific antibody complex elucidate the molecular basis of this strain-specific glycan hole response. We conclude that even for the immunodominant glycan hole shared between BG505 and B41, the prospect of designing prime-boost immunogens remains difficult.