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BACKGROUND: The purpose of this study was to compare outcomes between patients undergoing same-day discharge (SDD) total knee arthroplasty (TKA) at an ambulatory surgery center (ASC) versus a tertiary care university hospital setting. METHODS: A single tertiary academic center's institutional database was reviewed for patients that underwent primary TKA and were discharged the same day from August 2021 to January 2024. Patients who did not have at least one year of follow-up were excluded. Patient demographics, comorbidities, patient-reported outcome measures (PROMs), emergency department (ED) visits, admissions, reoperations, and revisions were collected. Patients were stratified by the location of their surgery: ASC versus hospital. Specific criteria had to be met prior to surgery at the ASC, and the final decision regarding the location of surgery was made via shared decision-making between the patient and their surgeon. Patients who did not meet ASC criteria underwent TKA at the main hospital. Univariable analyses were used to compare groups, and multivariable logistic regression was used to determine if surgical location was a significant factor. Of the 449 TKAs meeting inclusion criteria, 63.3% (284) were performed at the ASC and 36.7% (165) at the university hospital at a mean follow-up of 1.51 years (range, 1.00 to 2.40). Of those 165 whose surgery was done at the hospital, 93.9% met at least one ASC exclusion criteria. RESULTS: Patients whose TKA was done at the hospital had significantly higher weight (P = 0.003), body mass index (BMI) (P < 0.001), Elixhauser comorbidity index (ECI) (P < 0.001), proportion of patients who had an American Society of Anesthesiologists (ASA) classification of 3 (P = 0.023), and proportion of patients who required general anesthesia (P < 0.001). Additionally, patients whose TKA was done at the hospital had higher preoperative patient-reported outcome measurement information system (PROMIS) pain interference (PI) (62.0 [59.0, 66.0] versus 63.0 [61.8, 67.0]; P = 0.006), and lower physical function (PF) (39.0 [36.0, 43.0] versus 38.0 [34.0, 41.0]; P = 0.001). At 1 year, however, patients in both groups had similar PROMIS PI (53.0 [49.0, 59.0] versus 54.0 [44.0, 59.0]; P = 0.785) and PROMIS PF (47.0 [42.0, 51.0] versus 47.0 [41.0, 50.0]; P = 0422) scores as well as similar rates of achieving minimum clinically important difference (MCID) for PROMIS PI (64.4 versus 71.4%; P = 0.336) and PROMIS PF (60.5 versus 71.4%; P = 0.124). They also had a similar number of ED visits and admissions at 30 and 90 days, as well as similar reoperation-free (92.0 versus 93.3%; P = 0.79) and revision-free (95.5 versus 99.4%; P = 0.59) survival at 2 years. CONCLUSION: Although ASCs have strict patient criteria for SDD TKA, complex patients at a tertiary university hospital can be sent home the same day with equivalent outcomes. Therefore, unhealthier patients can safely achieve SDD without compromising outcomes if done in the appropriate setting.
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CASE: A 32-year-old woman with a history of hip fusion presented with significant lower back, hip, and knee pain as well as severely limited hip mobility and function. Single-stage fusion takedown and conversion to total hip arthroplasty (THA) was performed using augmented reality navigation. At 1 year, the patient was pain free with improved function. This study is the first to report the technique and outcomes of surgical fusion conversion to THA, using mixed reality navigation. CONCLUSION: Mixed reality navigation in complex conversion THA can be useful for identifying the patient's true acetabulum and for patient-specific acetabular component placement to maximize outcomes.
Subject(s)
Arthroplasty, Replacement, Hip , Humans , Female , Adult , Augmented Reality , Surgery, Computer-Assisted/methods , Hip Joint/surgery , Hip Joint/diagnostic imagingABSTRACT
BACKGROUND: This retrospective study investigated the impact of continuing vs discontinuing home oral hypoglycemic medications for patients with diabetes undergoing total hip arthroplasty. MATERIALS AND METHODS: Patients who were not exclusively receiving home oral hypoglycemic regimens were excluded. Additionally, patients whose diabetes was not managed inpatient postoperatively were excluded. Included patients were retrospectively evaluated for early postoperative glycemic control, renal function, and metabolic abnormalities. Patients were then compared based on whether their home oral hypoglycemic regimen was continued vs discontinued in favor of initiating insulin while inpatient and analyzed using multivariable regression analysis. RESULTS: A total of 532 patients undergoing total hip arthroplasty met inclusion criteria, with 78.6% continuing their home oral hypoglycemic regimen. Those who continued showed significantly lower median maximum inpatient blood glucose (178.5 mg/dL vs 249.5 mg/dL; P<.001) and median average inpatient blood glucose (138.4 mg/dL vs 178.6 mg/dL; P<.001). Linear regression analysis, adjusting for various potential confounding factors, revealed a positive correlation between discontinuation of home hypoglycemic medications and higher maximum in-patient blood glucose (ß=70.15 [95% CI, 59.27-81.03]; P<.001). Patients in the continuation group had lower proportions of acute kidney injury (18.7% vs 41.2%; P<.001) and metabolic acidosis (4.3% vs 17.5%; P<.001), along with a shorter length of stay (1.0 d vs 2.0 d; P<.001). CONCLUSION: These findings suggest that continuing a home oral hypoglycemic regimen for patients with diabetes after total hip arthroplasty is associated with superior glycemic control without exacerbating renal abnormalities or increasing metabolic complications. [Orthopedics. 202x;4x(x):xx-xx.].
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Introduction: Robotic-assisted total knee arthroplasty (rTKA) has gained interest from patients and surgeons alike. Robotic systems assist with gap balancing and bone cut accuracy, which can theoretically minimize post-operative pain by decreasing soft tissue damage. This study compared perioperative results, 30- and 90-day complications, patient-reported outcomes (PROs), and survivorship to all-cause revisions between patients undergoing traditional versus rTKA. Methods: A total of 430 TKAs (215 rTKA, 215 traditional) by two fellowship trained arthroplasty surgeons were retrospectively reviewed from 2017 to 2022. All rTKAs were performed using the CORI Surgical System (Smith & Nephew, Memphis, Tennessee). Cohorts were propensity score matched by age, sex, body mass index, and American Society of Anesthesiologist classification. Blood loss, surgical times, length of stays, 30- and 90-day complications, pain scores and PROs were compared with univariable analyses. Cox regression analyses evaluated survival to all-cause revisions. Results: Patients undergoing rTKA had a higher incidence of discharge home (86.5 %-60.0 %) (p < 0.01). There was no difference in blood loss or surgical time. rTKA pain scores were lower in-hospital mean 2 (range, 0 to 9) vs 3 (range, 0 to 9) (p = 0.02) as well as at one-year post-operatively, mean 1 (range, 0 to 7) vs 2 (range, 0 to 10) (p = 0.02). Cox hazard ratio demonstrated no difference in survival to all-cause revisions (HR 1.3; CI 0.5 to 3.7) (p = 0.64). Conclusion: This matched cohort analysis demonstrated potential short-term benefits associated with imageless second generation rTKA including improved early post-operative pain, without compromising survivorship to all-cause revisions.
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BACKGROUND: The purpose of this study was to evaluate the management and outcomes of aseptic revision total knee arthroplasty (arTKA) with unsuspected positive cultures (UPCs) compared to those with sterile cultures. METHODS: The institutional database at a single tertiary center was retrospectively reviewed for arTKA from January 2013 to October 2023. Patients who met Musculoskeletal Infection Society criteria for periprosthetic joint infection (PJI) based on available preoperative infectious workup, received antibiotic spacers, or did not have at least 1 year of follow-up were excluded. Patients were stratified based on intraoperative cultures into 4 cohorts: sterile cultures, 1 UPC, ≥ 2 UPCs with different organisms, and ≥ 2 UPCs with the same organism. Univariable analyses were used to compare these groups. Kaplan-Meier survivorship analysis assessed infection-free survival at 5 years, and Cox proportional hazards regressions were used to evaluate factors that influence infection-free survival. A total of 691 arTKAs at a mean follow-up of 4.2 years were included in the study. Of these, 49 (7.1%) had 1 UPC with a new organism, 10 (1.4%) had ≥2 UPCs of the same organism, and 2 (0.2%) had ≥2 UPCs with different organisms. RESULTS: Postoperative antibiotics were prescribed to 114 (16.5%) patients-13 (26.5%) with 1 UPC, 6 (60.0%) with ≥2 UPCs of the same organism, and 0 (0.0%) of patients who had ≥2 UPCs of different organisms. There were no differences in infection-free survival at 5 years between patients who had sterile cultures and 1 UPC (96 versus 89%; P = .39) nor between sterile cultures and ≥2 UPCs of different organisms (96 versus 100%; P < .72). However, patients who had ≥2 UPCs of the same organism had significantly worse infection-free survival at 5 years compared to patients who had sterile cultures (58 versus 96%; P < .001). Cox proportional hazards regression suggested that when adjusting for covariates, an American Society of Anesthesiologists classification of ≥3 (hazard ratio [HR] = 3.1; P = .007), ≥2 UPCs of the same organism (HR = 11.0; P < .001), 1 UPC (HR = 4.2; P = .018), and arTKA with hinge constructs (HR = 4.1; P = .008) were associated with increased risk of rerevision for PJI. CONCLUSIONS: Patients who had 1 UPC or ≥2 UPCs with different organisms had similar infection-free survival at 5 years as patients who had sterile cultures. However, patients who had ≥2 UPCs of the same organism had significantly worse infection-free survival at 5 years. Overall, 1 UPC or ≥2 UPCs of the same organism at the time of arTKA may suggest the patient is at higher risk of rerevision for PJI. More studies are needed to determine what interventions can be implemented to mitigate this risk.
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Aims: This study aims to assess the relationship between history of pseudotumour formation secondary to metal-on-metal (MoM) implants and periprosthetic joint infection (PJI) rate, as well as establish ESR and CRP thresholds that are suggestive of infection in these patients. We hypothesized that patients with a pseudotumour were at increased risk of infection. Methods: A total of 1,171 total hip arthroplasty (THA) patients with MoM articulations from August 2000 to March 2014 were retrospectively identified. Of those, 328 patients underwent metal artefact reduction sequence MRI and had minimum two years' clinical follow-up, and met our inclusion criteria. Data collected included demographic details, surgical indication, laterality, implants used, history of pseudotumour, and their corresponding preoperative ESR (mm/hr) and CRP (mg/dl) levels. Multivariate logistic regression modelling was used to evaluate PJI and history of pseudotumour, and receiver operating characteristic curves were created to assess the diagnostic capabilities of ESR and CRP to determine the presence of infection in patients undergoing revision surgery. Results: The rate of PJI for all identified MoM THAs was 3.5% (41/1,171), with a mean follow-up of 10.9 years (2.0 to 20.4). Of the patients included in the final cohort, 8.2% (27/328) had PJI, with a mean follow-up of 12.2 years (2.3 to 20.4). Among this cohort, 31.1% (102/328) had a history of pseudotumour. The rate of PJI in these patients was 14.7% (15/102), which was greater than those without pseudotumour, 5.3% (12/226) (p = 0.008). Additionally, logistic regression analysis showed an association between history of pseudotumour and PJI (odds ratio 4.36 (95% confidence interval 1.77 to 11.3); p = 0.002). Optimal diagnostic cutoffs for PJI in patients with history of pseudotumour versus those without were 33.1 mm/hr and 24.5 mm/hr for ESR and 7.37 mg/dl and 1.88 mg/dl for CRP, respectively. Conclusion: Patients with history of pseudotumour secondary to MoM THA had a higher likelihood of infection than those without. While suspicion of infection should be high for these patients, ESR and CRP cutoffs published by the European Bone and Joint Infection Society may not be appropriate for patients with a history of pseudotumour, as ESR and CRP levels suggestive of PJI are likely to be higher than for those without a pseudotumour. Additional investigation, such as aspiration, is highly recommended for these patients unless clinical suspicion and laboratory markers are low.
Subject(s)
Arthroplasty, Replacement, Hip , Granuloma, Plasma Cell , Hip Prosthesis , Metal-on-Metal Joint Prostheses , Prosthesis-Related Infections , Humans , Arthroplasty, Replacement, Hip/adverse effects , Male , Female , Granuloma, Plasma Cell/etiology , Middle Aged , Prosthesis-Related Infections/etiology , Retrospective Studies , Aged , Hip Prosthesis/adverse effects , Metal-on-Metal Joint Prostheses/adverse effects , Adult , Reoperation , Blood Sedimentation , Aged, 80 and over , C-Reactive Protein/analysis , Magnetic Resonance Imaging , Follow-Up Studies , Risk FactorsABSTRACT
BACKGROUND: This study evaluated blood glucose (BG), creatinine levels, metabolic issues, length of stay (LOS), and early postoperative complications in diabetic primary total knee arthroplasty (TKA) patients. It examined those who continued home oral antidiabetic medications and those who switched to insulin postoperatively. The hypothesis was that continuing home medications would lead to lower BG levels without metabolic abnormalities. METHODS: Patients who had diabetes who underwent primary TKA from 2013 to 2022 were evaluated retrospectively. Diabetic patients who were not on home oral antidiabetic medications or who were not managed as an inpatient postoperatively were excluded. Patient demographics and laboratory tests collected preoperatively and postoperatively as well as 90-day emergency department visits and 90-day readmissions, were pulled from electronic records. Patients were grouped based on inpatient diabetes management: continuation of home medications versus new insulin coverage. Acute postoperative BG control, creatinine levels, metabolic abnormalities, LOS, and early postoperative complications were compared between groups. Multivariable regression analyses were performed to measure associations. RESULTS: A total of 867 primary TKAs were assessed; 703 (81.1%) patients continued their home oral antidiabetic medications. Continuing home antidiabetic medications demonstrated lower median maximum inpatient BG (180.0 mg/dL versus 250.0 mg/dL; P < .001) and median average inpatient BG (136.7 mg/dL versus 173.7 mg/dL; P < .001). Logistic regression analyses supported the presence of an association (odds ratio = 17.88 [8.66, 43.43]; P < .001). Proportions of acute kidney injury (13.5 versus 26.7%; P < .001) were also lower. There was no difference in relative proportions of metabolic acidosis (4.4 versus 3.7%; P = .831), LOS (2.0 versus 2.0 days; P = .259), or early postoperative complications. CONCLUSIONS: Continuing home oral antidiabetic medications after primary TKA was associated with lower BG levels without an associated worsening creatinine or increase in metabolic acidosis. LEVEL III EVIDENCE: Retrospective Cohort Study.
Subject(s)
Arthroplasty, Replacement, Knee , Blood Glucose , Hypoglycemic Agents , Insulin , Humans , Hypoglycemic Agents/administration & dosage , Hypoglycemic Agents/therapeutic use , Female , Male , Aged , Retrospective Studies , Middle Aged , Insulin/administration & dosage , Blood Glucose/analysis , Blood Glucose/metabolism , Administration, Oral , Postoperative Complications/etiology , Postoperative Complications/epidemiology , Postoperative Complications/prevention & control , Length of Stay/statistics & numerical data , Glycemic Control , Diabetes Mellitus/drug therapy , Diabetes Mellitus/blood , Postoperative PeriodABSTRACT
PURPOSE: To assess return to sport (RTS) in the high-risk young athlete population with capitellar osteochondritis dissecans (OCD) undergoing arthroscopic microfracture (MFX) with or without debridement as well as associated indications, clinical outcomes, radiographic outcomes, and complications. METHODS: A literature search of all published literature in the English language from PubMed, EMBASE, Scopus, and Cochrane from database inception to April 4, 2022, was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Included studies presented demographics and outcomes for adolescent (<21 years old) patients diagnosed with capitellar OCD who underwent arthroscopic MFX (or drilling/subchondral drilling) or MFX (or drilling/subchondral drilling) with debridement (or loose body removal/chondroplasty). Studies containing multiple surgical techniques that did not distinguish characteristics and outcomes of individual patients by surgical technique were excluded. Additionally, if there was overlap in patient populations between 2 studies, the study with less outcome data was excluded. Extracted data included study properties, patient demographics, lesion characteristics, surgery details, and patient outcomes, including range of motion, outcome scores, and RTS rates. Bias was assessed via the Methodological Index for Non-Randomized Studies (MINORS). RESULTS: Nine studies of 136 patients and 138 elbows met criteria. Included articles were published between 2005 and 2020 with MINORS scores of 8 to 14 (50% to 88%). The age ranged from 12.7 to 15.7 years with most patients being involved in baseball or gymnastics and a rate of dominant elbow involvement of 55% to 100%. Patient follow-up ranged from 16 to 138 months. All 9 studies reported RTS, ranging from 65% to 100%. Six of these studies categorized the level to which the patient returned, with patients RTS at the same level of competition ranging from 60% to 100%. Six studies reported complications, with a range rate of 0% to 43%; there were a total of 10 complications, 7 of which required reoperations. CONCLUSIONS: Arthroscopic MFX with or without arthroscopic debridement is a safe and effective treatment for OCD lesions of the capitellum in young, athletic patients. Included studies reported improved clinical, radiographic, and patient-reported outcomes. Aside from 1 study reporting an RTS of 65%, the rate of RTS ranged from 86% to 100%. The percentage of patients returning to sport at the same level of competition ranged from 60% to 100% with a time to RTS ranging from 4.1 to 5 months. A single study reported a complication rate of 43%, while remaining studies reported complication rates between 0% and 19%, with loose bodies being the most common complication requiring reoperation. Follow-up ranged from 16 to 138 months. LEVEL OF EVIDENCE: Level IV, systematic review of Level IV studies.
Subject(s)
Elbow Joint , Fractures, Stress , Joint Loose Bodies , Osteochondritis Dissecans , Return to Sport , Adolescent , Child , Humans , Young Adult , Arthroscopy , Athletes , Elbow Joint/surgery , Joint Loose Bodies/surgery , Osteochondritis Dissecans/surgery , Sports , Treatment OutcomeABSTRACT
BACKGROUND: Orthopedic surgery is among the least diverse specialties in medicine. This systematic review analyzes gender, racial, and ethnic diversity within orthopedic sports medicine and aims to raise awareness and provide guidance for future strategies that support underrepresented minorities in medicine (URMs) and women in joining the orthopedic sports medicine workforce. We hypothesize that at all tiers of training, there is a lack of gender, racial, and ethnic parity in academic rank, leadership positions, and research productivity. METHODS: A search of all published literature in the English language from PubMed, Embase, Cochrane, and Scopus databases, between January 1, 2010, and August 18, 2023, was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Included studies presented demographics regarding diversity within orthopedic sports medicine and provided trends in applicants, attendings, leadership, and/or research. Bias was assessed using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) study checklist. RESULTS: Thirteen studies published between 2016 and 2023 with STROBE scores 15.5 to 21.5 (70.5% to 97.7%) met criteria, and pertinent data were extracted. The percent of female orthopedic sports medicine surgeons from 2010 to 2019 increased from 5% (n = 138) to 6% (n = 206) with a compound annual growth rate of 0.2% (r2 = 0.97; p < 0.001). Females and URMs are underrepresented at the highest levels of orthopedic sports medicine leadership including department chair (female: 0% [n = 0]), division chief (female: 4% [n = 4]; URM: 3% [n = 3]), and fellowship director (female: 3.3% [n = 3]; URM: 4.4% [n = 4]). Studies from prominent orthopedic sports medicine journals (American Journal of Sports Medicine, Arthroscopy, Journal of Shoulder and Elbow Surgery, and Sports Health) show a 12.1% increase in female involvement in orthopedic sports medicine research from 1972 to 2018; however, this increase captures 59.3% (n = 2,953) females with degrees other than an MD. CONCLUSIONS: Although increasingly more females and underrepresented minorities are joining orthopedic sports medicine, the rate of diversification remains slow and current involvement in leadership and research is minimal. Targeted efforts aimed at increasing research opportunities and inspiring interest through mentorship for URMs and females in orthopedics is essential to drive change toward parity. LEVEL OF EVIDENCE: Level IV. Systematic Review. See Instructions for Authors for a complete description of levels of evidence.
Subject(s)
Orthopedic Surgeons , Orthopedics , Sports Medicine , Humans , Female , United States , Arthroscopy , PublicationsABSTRACT
An adolescent female patient presented with atraumatic left knee pain and limited flexion. MRI demonstrated evidence of a soft tissue lesion abutting the posterior cruciate ligament. Differential diagnosis included pigmented villonodular synovitis (PVNS) and fibroma of the tendon sheath (FTS). Following arthroscopic biopsy, histopathological evaluation confirmed FTS. The tumour was then excised via an arthroscopic approach. This case report provides a unique example of FTS abutting the cruciate ligaments in an uncommonly young female patient. It highlights the importance of including benign processes, such as FTS, in the differential with more aggressive-type diagnoses like PVNS. Furthermore, this case exemplifies an appropriate surgical indication for FTS. Finally, it emphasises the importance of communication and collaboration among orthopaedic subspecialists in providing safe and effective arthroscopic treatment of this unique tumour presentation.
Subject(s)
Fibroma , Synovitis, Pigmented Villonodular , Adolescent , Female , Fibroma/diagnostic imaging , Fibroma/surgery , Humans , Knee Joint/diagnostic imaging , Knee Joint/pathology , Knee Joint/surgery , Synovectomy , Synovitis, Pigmented Villonodular/diagnosis , Tendons/pathology , Tendons/surgeryABSTRACT
Paclitaxel is a key member of the Taxane (paclitaxel [originally named taxol], docetaxel/Taxotere) family of successful drugs used in the current treatment of several solid tumors, including ovarian cancer. The molecular target of paclitaxel has been identified as tubulin, and paclitaxel binding alters the dynamics and thus stabilizes microtubule bundles. Traditionally, the anticancer mechanism of paclitaxel has been thought to originate from its interfering with the role of microtubules in mitosis, resulting in mitotic arrest and subsequent apoptosis. However, recent evidence suggests that paclitaxel operates in cancer therapies via an as-yet-undefined mechanism rather than as a mitotic inhibitor. We found that paclitaxel caused a striking break up of nuclei (referred to as multimicronucleation) in malignant ovarian cancer cells but not in normal cells, and susceptibility to undergo nuclear fragmentation and cell death correlated with a reduction in nuclear lamina proteins, lamin A/C. Lamin A/C proteins are commonly lost, reduced, or heterogeneously expressed in ovarian cancer, accounting for the aberration of nuclear shape in malignant cells. Mouse ovarian epithelial cells isolated from lamin A/C-null mice were highly sensitive to paclitaxel and underwent nuclear breakage, compared to control wild-type cells. Forced overexpression of lamin A/C led to resistance to paclitaxel-induced nuclear breakage in cancer cells. Additionally, paclitaxel-induced multimicronucleation occurred independently of cell division that was achieved by either the withdrawal of serum or the addition of mitotic inhibitors. These results provide a new understanding for the mitotis-independent mechanism for paclitaxel killing of cancer cells, where paclitaxel induces nuclear breakage in malignant cancer cells that have a malleable nucleus but not in normal cells that have a stiffer nuclear envelope. As such, we identify that reduced nuclear lamin A/C protein levels correlate with nuclear shape deformation and are a key determinant of paclitaxel sensitivity of cancer cells.
Subject(s)
Lamin Type A/drug effects , Microtubules/drug effects , Ovarian Neoplasms/drug therapy , Paclitaxel/pharmacology , Animals , Antimitotic Agents/pharmacology , Apoptosis/drug effects , Cell Line, Tumor , Drug Resistance, Neoplasm/drug effects , Female , Humans , Lamin Type A/metabolism , Mice, Transgenic , Microtubules/metabolism , Mitosis/drug effects , Ovarian Neoplasms/pathology , Tubulin/drug effects , Tubulin/metabolismABSTRACT
There is growing interest in the use of nonmodel microorganisms as hosts for biopharmaceutical manufacturing. These hosts require genomic engineering to meet clinically relevant product qualities and titers, but the adaptation of tools for editing genomes, such as CRISPR-Cas9, has been slow for poorly characterized hosts. Specifically, a lack of biochemical characterization of RNA polymerase III transcription has hindered reliable expression of guide RNAs in new hosts. Here, we present a sequencing-based strategy for the design of host-specific cassettes for modular, reliable, expression of guide RNAs. Using this strategy, we achieved up to 95% gene editing efficiency in the methylotrophic yeast Komagataella phaffii. We applied this approach for the rapid, multiplexed engineering of a complex phenotype, achieving humanized product glycosylation in two sequential steps of engineering. Reliable extension of simple gene editing tools to nonmodel manufacturing hosts will enable rapid engineering of manufacturing strains tuned for specific product profiles and potentially decrease the costs and timelines for process development.