Outpatient Total Joint Arthroplasty in the "Unhealthy": Staying Safe Using Institutional Protocols.

BACKGROUND: Recent expansion in the indications for outpatient total joint arthroplasty has led to debates over patient selection. The purpose of this study was to compare early clinical outcomes and complications of same-day discharge (SDD) hip and knee arthroplasties from a high-volume institution based on the American Society of Anesthesiologists (ASA) physical status classification. METHODS: Prospectively collected data were reviewed for all SDD primary joint arthroplasties between January 2013 and August 2023. There were 8 surgeons who performed 7,258 cases at hospital outpatient (n = 4,288) or ambulatory surgery centers (n = 2,970). This included 3,239 total hip arthroplasties, 1,503 total knee arthroplasties, and 2,516 unicompartmental knee arthroplasties. The ASA 1 group comprised 506 subjects, compared to 5,005 for ASA 2 and 1,736 for ASA 3. The primary outcomes included emergency department (ED) visits, readmissions, complications, and revisions within 24 hours and 90 days of surgery. The ASA 3 group was older (ASA 1 = 55 versus ASA 2 = 63 versus ASA 3 = 66 years; P < .01) and had a higher body mass index (ASA 1 = 25.4 versus ASA 2 = 28.5 versus ASA 3 = 32.7; P < .01). RESULTS: There were no differences between ASA groups in joint-related ED visits, readmissions, and complications within 24 h and 90 days of surgery (P > .05). Subjects in the ASA 3 group experienced greater 90-day revisions compared to the other groups (ASA 1 = 1 of 506, 0.2% versus ASA 2 = 15 of 5,005, 0.3% versus ASA 3 = 15 of 1,736, 0.9%; P = .01). Regarding systemic events, ASA 1 subjects experienced significantly greater 24-hour complications (8 of 506, 1.6%) and ED visits (5 of 506, 1.0%), and the ASA 3 subjects had a higher incidence of 90-day readmissions (19 of 1,736, 1.1%) compared to the other groups (P < .05). Within 24 hours of discharge, urinary retention and syncope were the most frequent complications that required additional health care utilization. CONCLUSIONS: Medically optimized patients categorized as ASA 3 can safely undergo SDD hip and knee arthroplasty without increased risk of 24-hour or 90-day complications. Patient preference for outpatient care, reliable social support, and independent functional status are imperative for a successful outpatient program.

The Effect of the COVID Pandemic on the Rate of Same-Day Discharge in Primary Hip and Knee Arthroplasty.

BACKGROUND: Same-day discharge (SDD) following primary total hip arthroplasty (THA) and total knee arthroplasty (TKA) started increasing prior to 2020. The purpose of this study was to evaluate the change in the rate of SDD after the pandemic and determine whether those changes became permanent. METHODS: The annual rate of SDD for 15,208 primary THA and TKA cases performed between January 1, 2015, and September 9, 2022, at a single institution was determined. We also examined changes in SDD patient demographics as well as differences in the 90-day complication rates of SDD and overnight patients. RESULTS: In 2015, the rate of SDD for primary arthroplasty was 24%, which grew annually to 29% in 2019. Postpandemic, the rate of SDD jumped above 50% and continued up to 64% by 2022. The biggest increase was in TKA, which went from under 10% SDD prepandemic to 50% by 2022. The average age and body mass index of SDD cases prepandemic increased significantly to 62 ± 9 years and 29.4 ± 5.3 (P < .01). Overnight patients had higher rates of 90-day postoperative complications (8.4 versus 4.2%, P < .00001). CONCLUSIONS: The pandemic caused major changes in the rate of SDD for primary THA and TKA, increasing in subsequent years. The SDD patients became older and heavier due to the expanded criteria for SDD cases. The 90-day postoperative complication rate was lower for SDD patients since higher risk patients were kept overnight. At the prepandemic rate, 29% of patients currently being sent home would have stayed overnight.

Advanced Concepts in Outpatient Joint Arthroplasty.

As the adoption and utilization of outpatient total joint arthroplasty continues to grow, key developments have enabled surgeons to safely and effectively perform these surgeries while increasing patient satisfaction and operating room efficiency. Here, the authors will discuss the evidence-based principles that have guided this paradigm shift in joint arthroplasty surgery, as well as practical methods for selecting appropriate candidates and optimizing perioperative care. There will be 5 core efficiency principles reviewed that can be used to improve organizational management, streamline workflow, and overcome barriers in the ambulatory surgery center. Finally, future directions in outpatient surgery at the ASC, including the merits of implementing robot assistance and computer navigation, as well as expanding indications for revision surgeries, will be debated.

Outcomes Following Intraoperative Calcar Fractures During Cementless Total Hip Arthroplasty.

BACKGROUND: Intraoperative calcar fractures (IOCFs) are an established complication of cementless total hip arthroplasty (THA). Prompt recognition and management may prevent subsequent postoperative complications. This study aimed to evaluate the outcomes and revision rates of THAs with IOCFs identified and managed intraoperatively. METHODS: There were 11,438 primary cementless THAs performed at a single institution from 2009 to 2022. Prospectively collected data on cases with an IOCF was compared to cases without the complication. The fracture group had a lower body mass index (26.9 versus 28.9 kg/m2; P = .01). Patient age, sex, and mean follow-up (3.2 (0 to 12.8) versus 3.5 years (0 to 14); P = .45) were similar between groups. RESULTS: An IOCF occurred in 62 of 11,438 (0.54%) cases. The THAs done via a direct anterior approach experienced the lowest rate of fractures (31 of 7,505, 0.4%) compared to postero-lateral (27 of 3,759, 0.7%; P = .03) and lateral (4 of 165, 2.4%; P < .01) approaches. Of the IOCFs, 48 of 62 (77%) were managed with cerclage cabling, 4 of 62 (6.5%) with intraoperative stem design change and cabling, 4 of 62 (6.5%) with restricted weight-bearing, and 6 of 62 (9.7%) with no modification to the standard postoperative protocol. The IOCF group experienced one case of postoperative component subsidence. No subjects in the IOCF cohort required revision, and rates were similar between groups (0 of 62, 0% versus 215 of 11,376, 1.9%; P = .63). Postoperative Hip dysfunction and Osteoarthritis Outcome Score for Joint Replacement scores were comparable (85.7 versus 86.4; P = .80). CONCLUSIONS: Cementless THA complicated by IOCF had similar postoperative revision rates and patient-reported outcome measures at early follow-up when compared to patients not experiencing this complication. Surgeons may use these data to provide postoperative counseling on expectations and outcomes following these rare intraoperative events.

Early Practice All-Cause Complications for Fellowship-Trained Anterior Hip Surgeons Are Not Increased When Compared to "Gold Standard" Experienced Posterior Approach Surgeons.

BACKGROUND: Increased complication rates have been reported during the learning curve for direct anterior approach (DAA) total hip arthroplasty (THA). However, emerging literature suggests that complications associated with the learning curve may be substantially reduced with fellowship training. METHODS: Our institutional database was queried to identify 2 groups: (1) 600 THAs comprised of the first 300 consecutive cases performed by 2 DAA fellowship-trained surgeons; and (2) 600 posterolateral approach (PA) THAs, including the most recent 300 primary cases performed by 2 experienced PA surgeons. All-cause complications, revision rates, reoperations, operative times, and transfusion rates were evaluated. RESULTS: Comparing DAA and PA cases, there were no significant differences in rates of all-cause complications (DAA = 18, 3.0% versus PA = 23, 3.8%; P = .43), periprosthetic fractures (DAA = 5, 0.8% versus PA = 10, 1.7%; P = .19), wound complications (DAA = 7, 1.2% versus PA = 2, 0.3%; P = .09), dislocations (DAA = 2, 0.3% versus PA = 8, 1.3%, P = .06), or revisions (DAA = 2, 0.3% versus PL = 5, 0.8%; P = .45) at 120 days postoperatively. There were 4 patients who required reoperation for wound complications, all within the DAA group (DAA = 4, 0.67% versus PA = 0; P = .045). Operative times were shorter in the DAA group (DAA <1.5 hours = 93% versus PA <1.5 hours = 86%; P < .01). No blood transfusions were given in either group. CONCLUSION: In this retrospective study, DAA THAs performed by fellowship-trained surgeons early in practice were not associated with higher complication rates compared to THAs performed by experienced PA surgeons. These results suggest that fellowship training may allow DAA surgeons to complete their learning curve period with complication rates similar to experienced PA surgeons.

Outpatient Total Knee Arthroplasty From a Stand-Alone Surgery Center: Safe as the Hospital?

BACKGROUND: Literature suggests that outpatient arthroplasty may result in low rates of complications and readmissions. There is, however, a dearth of information on the relative safety of total knee arthroplasty (TKA) performed at stand-alone ambulatory surgery centers (ASCs) versus hospital outpatient (HOP) settings. We aimed to compare safety profiles and 90-day adverse events of these 2 cohorts. METHODS: Prospectively collected data were reviewed on all patients who underwent outpatient TKA from 2015 to 2022. The ASC and HOP groups were compared, and differences in demographics, complications, reoperations, revisions, readmissions, and emergency department (ED) visits within 90 days of surgery were analyzed. There were 4 surgeons who performed 4,307 TKAs during the study period, including 740 outpatient cases (ASC = 157; HOP = 583). The ASC patients were younger than HOP patients (ASC = 61 versus HOP = 65; P < .001). Body mass index and sex did not differ significantly between groups. RESULTS: Within 90 days, 44 (6%) complications occurred. No differences were observed between groups in rates of 90-day complications (ASC = 9 of 157, 5.7% versus HOP = 35 of 583, 6.0%; P = .899), reoperations (ASC = 2 of 157, 1.3% versus HOP = 3 of 583, 0.5%; P = .303), revisions (ASC = 0 of 157 versus HOP = 3 of 583, 0.5%; P = 1), readmissions (ASC = 3 of 157, 1.9% versus HOP = 8 of 583, 1.4%; P = .625), and ED visits (ASC = 1 of 157, 0.6% versus HOP = 3 of 583, 0.5%; P = .853). CONCLUSION: These results suggest that in appropriately selected patients, outpatient TKA can be safely performed in both ASC and HOP settings with similar low rates of 90-day complications, reoperations, revisions, readmissions, and ED visits.

Motor Nerve Palsy After Direct Anterior Versus Posterior Total Hip Arthroplasty: Incidence, Risk Factors, and Recovery.

BACKGROUND: There is limited literature on motor nerve palsy in modern total hip arthroplasty (THA). The purpose of this study was to establish the incidence of nerve palsy following THA using the direct anterior (DA) and postero-lateral (PL) approaches, identify risk factors, and describe the extent of recovery. METHODS: Using our institutional database, we examined 10,047 primary THAs performed between 2009 and 2021 using the DA (6,592; 65.6%) or PL (3,455; 34.4%) approach. Postoperative femoral (FNP) and sciatic/peroneal nerve palsies (PNP) were identified. Incidence and time to recovery was calculated, and association between surgical and patient risk factors and nerve palsy were evaluated using Chi-square tests. RESULTS: The overall rate of nerve palsy was 0.34% (34/10,047) and was lower with the DA approach (0.24%) than the PL approach (0.52%), P = .02. The rate of FNPs in the DA group (0.20%) was 4.3 times more than the rate of PNPs (0.05%), while in the PL group the rate of PNPs (0.46%) was 8 times more than that of FNPs (0.06%). Higher rates of nerve palsy were observed with women, shorter patients, and nonosteoarthritis preoperative diagnoses. Full recovery of motor strength occurred in 60% of cases with FNP and 58% of cases with PNP. CONCLUSION: Nerve palsy is rare after contemporary THA through the PL and DA approaches. The PL approach was associated with a higher rate of PNP, whereas the DA approach was associated with a higher rate of FNP. Femoral and sciatic/peroneal palsies had similar rates of complete recovery.

Spinal Anesthesia for Primary Hip and Knee Arthroplasty: Comparative Rates of Transient Neurological Symptoms and Urinary Retention Using Lidocaine, Mepivacaine, and Bupivacaine.

BACKGROUND: Short-acting spinal anesthetics enable rapid recovery after hip and knee arthroplasty; however, concerns with transient neurological symptoms (TNS) cause some to avoid using lidocaine. Postoperative urinary retention (POUR) is also a concern with spinal anesthesia. We sought to study the comparative rates of TNS and POUR between lidocaine, mepivacaine, and bupivacaine in a high-volume hip and knee arthroplasty setting. METHODS: Data for 1,217 primary THA, TKA, and unicompartmental knee arthroplasty cases were reviewed and grouped by spinal anesthetic agent (lidocaine, mepivacaine, or bupivacaine). Of the 1,217 cases, utilization was 523 lidocaine, 573 mepivacaine, and 121 bupivacaine. The incidence of TNS and POUR requiring catheterization was measured both by clinical evaluation as well as a questionnaire sent to patients 14 days postoperatively. RESULTS: The overall rate of TNS was 8%. With the numbers available, there was no difference in rates of TNS between groups (6.9% lidocaine, 9.2% mepivacaine, and 4.1% bupivacaine; P = .297). There was no difference in rates of TNS or POUR between THA and TKA/unicompartmental knee arthroplasty. Bupivacaine had a significantly higher rate of urinary retention (9.1%; P < .001) than mepivacaine (2.8%) or lidocaine (1.5%). CONCLUSION: This study showed no difference in the rate of TNS between the 3 common agents used in spinal anesthesia. Short-acting spinal anesthetics such as lidocaine and mepivacaine can lower the rate of POUR requiring catheterization, helping to enable rapid recovery after hip and knee arthroplasty.

Early Results of a Randomized Controlled Trial of Partial Versus Total Knee Arthroplasty.

BACKGROUND: Debate still exists regarding the benefits of unicompartmental (UKA) versus total knee arthroplasty (TKA) for the treatment of medial compartment osteoarthritis. The purpose of this randomized trial is to compare the early outcomes of UKA versus TKA. METHODS: One-hundred and seven candidates for UKA were randomized at two centers; 57 candidates received UKA and 50 received TKA. Six-week and 6-month outcome measures including Knee Injury and Osteoarthritis Outcome Score, Joint Replacement (KOOS, JR), Knee Society Score (KSS), Forgotten Joint Score (FJS), and VR-12 global health scores were obtained. No demographic or baseline patient reported outcome (PRO) differences were present suggesting successful randomization (P > .05). RESULTS: UKA demonstrated shorter operative times (UKA = 65 minutes, TKA = 74 minutes; P < .001) and length of stay (UKA = 0.7 nights, TKA = 1.2 nights; P < .01). At 6 weeks, there were no differences in KOOS, JR (P = .755), KSS (P = .754), FJS (P = .664), or PRO change from preoperative scores (P = .468). There were three surgical complications within 90 days in each group. The duration of opioid consumption (UKA = 33.8 days, TKA = 28.5 days; P = .290) and return to work (UKA = 57.1 days, TKA = 47.3 days; P = .346) did not differ between groups. CONCLUSION: Data suggest no clinically significant differences between UKA and TKA in the early postoperative period in regards to patient-reported outcome measures, duration of opioid use, or return to work. Patients undergoing UKA can anticipate a shorter length of stay and greater early range of motion. All-cause short-term complications may be more prevalent with TKA.

The Efficacy and Safety of Regional Nerve Blocks in Total Knee Arthroplasty: Systematic Review and Direct Meta-Analysis.

BACKGROUND: Regional nerve blocks are widely used in primary total knee arthroplasty (TKA) to reduce postoperative pain and opioid consumption. The purpose of our study was to evaluate the efficacy and safety of regional nerve blocks after TKA in support of the combined clinical practice guidelines of the American Association of Hip and Knee Surgeons, American Academy of Orthopaedic Surgeons, Hip Society, Knee Society, and American Society of Regional Anesthesia and Pain Management. METHODS: We searched MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials for studies published before March 24, 2020 on femoral nerve block, adductor canal block, and infiltration between Popliteal Artery and Capsule of Knee in primary TKA. All included studies underwent qualitative and quantitative homogeneity testing followed by a systematic review and direct comparison meta-analysis to assess the efficacy and safety of the regional nerve blocks compared to a control, local peri-articular anesthetic infiltration (PAI), or between regional nerve blocks. RESULTS: Critical appraisal of 1,673 publications yielded 56 publications representing the best available evidence for analysis. Femoral nerve and adductor canal blocks are effective at reducing postoperative pain and opioid consumption, but femoral nerve blocks are associated with quadriceps weakness. Use of a continuous compared to single shot adductor canal block can improve postoperative analgesia. No difference was noted between an adductor canal block or PAI regarding postoperative pain and opioid consumption, but the combination of both may be more effective. CONCLUSION: Single shot adductor canal block or PAI should be used to reduce postoperative pain and opioid consumption following TKA. Use of a continuous adductor canal block or a combination of single shot adductor canal block and PAI may improve postoperative analgesia in patients with concern of poor postoperative pain control.

The Efficacy and Safety of Regional Nerve Blocks in Total Hip Arthroplasty: Systematic Review and Direct Meta-Analysis.

BACKGROUND: Regional nerve blocks may be used as a component of a multimodal analgesic protocol to manage postoperative pain after primary total hip arthroplasty (THA). The purpose of our study was to evaluate the efficacy and safety of regional nerve blocks after THA in support of the combined clinical practice guidelines of the American Association of Hip and Knee Surgeons, American Academy of Orthopaedic Surgeons, Hip Society, Knee Society, and American Society of Regional Anesthesia and Pain Management. METHODS: We searched MEDLINE, Embase, and the Cochrane Central Register of Controlled Trials for studies published prior to March 24, 2020 on fascia iliaca, lumbar plexus, and quadratus lumborum blocks in primary THA. All included studies underwent qualitative and quantitative homogeneity testing followed by a systematic review and direct comparison meta-analysis to assess the efficacy and safety of the regional nerve blocks. RESULTS: An initial critical appraisal of 3,382 publications yielded 11 publications representing the best available evidence for an analysis. Fascia iliaca, lumbar plexus, and quadratus lumborum blocks demonstrate the ability to reduce postoperative pain and opioid consumption. Among the available comparisons, no difference was noted between a regional nerve block or local periarticular anesthetic infiltration regarding postoperative pain and opioid consumption. CONCLUSION: Local periarticular anesthetic infiltration should be considered prior to a regional nerve block due to concerns over the safety and cost of regional nerve blocks. If a regional nerve block is used in primary THA, a fascia iliaca block is preferred over other blocks due to the differences in technical demands and risks associated with the alternative regional nerve blocks.

Periprosthetic Femur Fracture Risk: Influenced by Stem Choice, Not Surgical Approach.

BACKGROUND: Periprosthetic femur fracture (PFF) remains a common reason for failure after total hip arthroplasty (THA). For over 10 years, our institution has performed both anterior approach (AA) and posterolateral (PL) approaches for primary THA with multiple stem designs. The aim of this study is to determine the 90-day relative risk of PFF with regard to approach and stem design. METHODS: A retrospective review of our institutional database was performed on all patients undergoing primary THA from 2007 to 2018 using AA or PL approaches. Five surgeons performing 6309 THAs (AA = 4510; PL = 1799) using single-wedge taper (n = 2417) or fit-and-fill (n = 3892) stems were included. PFF occurring within 90 days of the index procedure were analyzed. Differences in PFF rates, fracture location, stem type, and treatment method were assessed. Comparisons were made using a Cox regression analysis. RESULTS: The 90-day revision rate for fracture was 0.3%. Clinically significant fractures requiring cerclage cabling, stem change, revision, or open reduction internal fixation occurred in 0.9% of patients (intraoperative = 37, 0.6%; postoperative = 17, 0.3%). Cox regression found PFF risk was significant for female patients (P = .008), patients older than age 65 (P < .01), single-wedge taper stems (P = .05), and for cases with collarless stems (P = .04). Among PFF cases that required surgical intervention, risk factors were female sex, age older than 65, and body mass index under 25 (P < .05). Collarless stems were 2.6 times more likely to result in PFF than collared stems (P = .04). Single-wedge taper stems were 2.3 times more likely to result in PFF than fit-and-fill stems (P = .05). Approach was not found to be an independent risk factor for PFF (P = .85). CONCLUSION: Our single-center experience demonstrates the risk of periprosthetic fracture within 90 days of surgery is significantly lower with collared stems and fit-and-fill stem designs. Female sex, age over 65, and body mass index below 25 nearly double the PFF risk. Surgical approach did not influence fracture rates.

Custom Triflange Cups: 20-Year Experience.

BACKGROUND: The custom triflange acetabular component is used during revision THA to address severe acetabular bone loss. Midterm results are promising, with low rates of loosening and triflange revision reported. However, reoperation and overall complication rates remain high. We aim to investigate our institution's custom triflange experience over 20 years by evaluating implant survivorship, reoperations, complications, and clinical outcomes. METHODS: Prospectively collected data were reviewed for 50 patients undergoing revision THA with the use of a triflanged component from January 2000 to December 2018. 94% among these cases had a known outcome or minimum two year follow-up. Outcomes related to the triflange component were recorded, including revisions, reoperations, surgical complications, medical complications, Harris hip scores, and patient satisfaction. Phone interviews were conducted with patients whose recent follow-up exceeded 2 years. Radiographic review was performed to define implants as either stable or unstable. RESULTS: The average Harris hip scores improved 24 points (49 to 73; P < .001). 91% of eligible patients were satisfied at follow-up. One patient was scheduled for revision at an outside institution during the study period. There were 2 reoperations (1 acute infection and 1 screw removal). One patient died due to pulmonary thromboembolism. A Trendelenberg gait was present in 46% (23/50) of patients. There were 14 major complications (28%). Dislocation (12%) was the most common complication. CONCLUSION: Custom triflange components provide a reliable solution for managing complex acetabular defects in revision THA. Patients should be counseled on magnitude of surgery and the high incidence of complications, specifically infection and dislocation.

Alignment in Medial Fixed-Bearing Unicompartmental Knee Arthroplasty: The Limb Has a Leg Up on the Component.

BACKGROUND: To assess how implant alignment affects unicompartmental knee arthroplasty (UKA) outcome, we compared tibial component alignment of well-functioning UKAs against 2 groups of failed UKAs, revised for progression of lateral compartment arthritis ("Progression") and aseptic loosening ("Loosening"). METHODS: We identified 37 revisions for Progression and 61 revisions for Loosening from our prospective institutional database of 3351 medial fixed-bearing UKAs performed since 2000. Revision cohorts were matched on age, gender, body mass index, and postoperative range of motion with "Successful" unrevised UKAs with minimum 10-year follow-up and Knee Society Score ≥70. Tibial component coronal (TCA) and sagittal (TSA) plane alignment was measured on postoperative radiographs. Limb alignment was quantified by hip-knee-ankle (HKA) angle on long-leg radiographs. In addition to directly comparing groups, a multivariate logistic regression examined how limb and component alignments were associated with UKA revision. RESULTS: In the Progression group, component alignment was similar to the matched successes (TCA 3.6° ± 3.5° varus vs 5.1° ± 3.5° varus, P = .07; TSA 8.4° ± 4.4° vs 8.8° ± 3.6°, P = .67), whereas HKA angle was significantly more valgus (0.3° ± 3.6° valgus vs 4.4° ± 2.6° varus, P < .001). Loosening group component alignment was also similar to the matched successes (TCA 6.1° ± 3.7° varus vs 5.9° ± 3.1° varus, P = .72; TSA 8.4° ± 4.6° vs 8.1° ± 3.9°, P = .68), and HKA was significantly more varus (6.1° ± 3.1° varus vs 4.0° ± 2.7° varus, P < .001). Using a multivariate logistic regression, HKA angle was the most significant factor associated with revision (P < .001). CONCLUSION: In this population of revised UKAs and long-term successes, limb alignment was a more important determinant of outcome than tibial component alignment. LEVEL OF EVIDENCE: Level III case-control study.

Independent Risk Factors for Transfusion in Contemporary Revision Total Hip Arthroplasty.

BACKGROUND: The incidence of transfusion in contemporary revision total hip arthroplasty (THA) remains high despite recent advances in blood management, including the use of tranexamic acid. The purpose of this prospective investigation was to determine independent risk factors for transfusion in revision THA. METHODS: Six centers prospectively collected data on 175 revision THAs. A multivariable logistic analysis was performed to determine independent risk factors for transfusion. Revisions were categorized into subgroups for analysis, including femur-only, acetabulum-only, both-component, explantation with spacer, and second-stage reimplantation. Patients undergoing an isolated modular exchange were excluded. RESULTS: Twenty-nine patients required at least one unit of blood (16.6%). In the logistic model, significant risk factors for transfusion were lower preoperative hemoglobin, higher preoperative international normalized ratio (INR), and longer operative time (P < .01, P = .04, P = .05, respectively). For each preoperative 1g/dL decrease in hemoglobin, the chance of transfusion increased by 79%. For each 0.1-unit increase in the preoperative INR, transfusion chance increased by 158%. For each additional operative hour, the chance of transfusion increased by 74%. There were no differences in transfusion rates among categories of revision hip surgery (P = .23). No differences in demographic or surgical variables were found between revision types. CONCLUSION: Despite the use of tranexamic acid, transfusions are commonly required in revision THA. Preoperative hemoglobin and INR optimization are recommended when medically feasible. Efforts should also be made to decrease operative time when technically possible.

The Impact of Coronal Alignment on Revision in Medial Fixed-Bearing Unicompartmental Knee Arthroplasty.

BACKGROUND: To better define the optimal alignment target for medial fixed-bearing unicompartmental knee arthroplasty (UKA), this study compares the postoperative mechanical alignment of well-functioning UKAs against 2 groups of failed UKAs, including revisions for progression of lateral compartment osteoarthritis ("Progression") and revisions for aseptic loosening or subsidence ("Loosening"). METHODS: From our prospective institutional database of 3351 medial fixed-bearing UKAs performed since 2000, we identified 37 UKAs revised for Progression and 61 UKAs revised for Loosening. Each of these revision cohorts was matched based on age at surgery, gender, body mass index, and postoperative range of motion with unrevised UKAs that had at least 10 years of follow-up and a Knee Society Score of 70 or greater without subtracting points for alignment ("Success" groups). Postoperative alignment was quantified by the hip-knee-ankle (HKA) angle measured on long-leg alignment radiographs. RESULTS: The mean HKA angle at 4-month follow-up for the Progression group was 0.3° ± 3.6° of valgus compared to 4.4° ± 2.6° of varus for the matched Success group (P < 0.001). For the Loosening group, the mean HKA angle was 6.1° ± 3.1° of varus versus 4.0° ± 2.7° of varus for the matched Success group (P < 0.001). CONCLUSIONS: Patients with well-functioning UKAs at 10 years exhibited mild varus mechanical alignment of approximately 4°, whereas patients revised for progression of osteoarthritis averaged more valgus and those revised for loosening or subsidence averaged more varus. The optimal mechanical alignment for medial fixed-bearing UKA survival with contemporary polyethylene is likely slight varus.

Outpatient Total Hip Arthroplasty Performed at an Ambulatory Surgery Center vs Hospital Outpatient Setting: Complications, Revisions, and Readmissions.

BACKGROUND: Outpatient total hip arthroplasty (THA) utilization continues to grow. Literature suggests outpatient THA may result in low rates of complications and readmission. There are no studies comparing safety profiles of THA performed at ambulatory surgery centers (ASC) vs hospital outpatient (HOP) settings. METHODS: Prospectively collected data were reviewed on all patients who underwent THA from 2013 to 2018. ASC and HOP subgroups were compared, investigating difference in demographics, comorbidities, American Society of Anesthesiologists subgroups, all complications, revisions, emergency department (ED) visits, and readmissions within the first 90 days of surgery. An additional subgroup analysis of patients younger than 65 years was performed. RESULTS: Two surgeons performed 3063 THAs during the study period, including 965 outpatient cases (ASC = 335; HOP = 630). Thirty-seven (3.8%) complications occurred within 90 days. No differences were found between groups for 90-day complication rates (ASC = 13, 3.9%; HOP = 24, 3.8%; P = .48), revision rates (ASC = 0, 0%; HOP = 2, .3%; P = .30), all-cause reoperation rates (ASC = 1, 0.3%; HOP = 5, 0.8%; P = .35), ED visits (ASC = 3, 0.9%; HOP = 2, 0.3%; P = .23), or readmission rates (ASC = 2, 0.6%; HOP = 9, 1.4%; P = .25). CONCLUSION: THA can be safely performed in both ASC and HOP settings with low 90-day postoperative complication, revision, reoperation, ED visit, and readmission rates. Based on the populations studied, we identified no statistically significant differences in rates of complications between ASC and HOP groups.

Prospective Validation of a Demographically Based Primary Total Knee Arthroplasty Size Calculator.

BACKGROUND: Preoperative planning for total knee arthroplasty (TKA) is essential for streamlining operating room efficiency and reducing costs. Digital templating and patient-specific instrumentation have shown some value in TKA but require additional costs and resources. The purpose of this study was to validate a previously published algorithm that uses only demographic variables to accurately predict TKA tibial and femoral component sizes. METHODS: Four hundred seventy-four consecutive patients undergoing elective primary TKA were prospectively enrolled. Four surgeons were included, three of which were unaffiliated with the retrospective cohort study. Patient sex, height, and weight were entered into our published Arthroplasty Size Prediction mobile application. Accuracy of the algorithm was compared with the actual sizes of the implanted femoral and tibial components from 5 different implant systems. Multivariate regression analysis was used to identify independent risk factors for inaccurate outliers for our model. RESULTS: When assessing accuracy to within ±1 size, the accuracies of tibial and femoral components were 87% (412/474) and 76% (360/474). When assessing accuracy to within ±2 sizes of predicted, the tibial accuracy was 97% (461/474), and the femoral accuracy was 95% (450/474). Risk factors for the actual components falling outside of 2 predicted sizes include weight less than 70 kg (odds ratio = 2.47, 95% confidence interval [1.21-5.06], P = .01) and use of an implant system with <2.5 mm incremental changes between femoral sizes (odds ratio = 5.50, 95% confidence interval [3.33-9.11], P < .001). CONCLUSIONS: This prospective series of patients validates a simple algorithm to predict component sizing for TKA with high accuracy based on demographic variables alone. Surgeons can use this algorithm to simplify the preoperative planning process by reducing unnecessary trays, trials, and implant storage, particularly in the community or outpatient setting where resources are limited. Further assessment of components with less than 2.5-mm differences between femoral sizes is required in the future to make this algorithm more applicable worldwide.

Radial head replacement with a bipolar system: an average 10-year follow-up.

BACKGROUND: We report the long-term results of a cohort of patients after radial head replacement with a bipolar design and a smooth cementless stem at a mean follow-up of 10.4 years. METHODS: Of 17 possible patients from a previous minimum 2-year follow-up study, 16 were available for review. Patients were assessed using clinical and radiographic examination and with standardized outcome measures. Range of motion, stability, and radiographic evaluation of implant loosening and joint degeneration were assessed. Comparisons were performed using the Wilcoxon signed rank test for unequal groups. RESULTS: The average follow-up was 10.5 years (range, 8.5-12 years). The median visual analog scale was 1 (range, 0-5), Minnesota Elbow Performance Index was 93 (range, 70-100), and the Disabilities of the Arm, Shoulder and Hand was 7.5 (range, 0-53). Range of motion was decreased on the operative side compared with the nonoperative side for flexion/extension (P = .005) and pronation/supination (P = .015). Grip strength was decreased on the affected side (P = .045). No patients had elbow instability. Significant arthritic changes developed in 2 patients at the ulnohumeral joint. The median cantilever quotient was 0.4 (range, 0.30-0.50). Osteolysis in zones 1 to 7 was found in all but 2 patients. The median stem radiolucency was 0.5 mm (range, 0.2-0.9 mm). No reoperations occurred since our previous report. Implant survival in this cohort was 97%. CONCLUSION: Bipolar radial head prosthesis with a smooth cementless stem effectively restores elbow stability and function after comminuted radial head fractures with or without concomitant elbow instability. Our study demonstrates excellent long-term implant survival.

The Influence of Patient Gender on Morbidity Following Total Hip or Total Knee Arthroplasty.

BACKGROUND: Little research has focused on the influence of gender on postoperative morbidity following total hip arthroplasty (THA) and total knee arthroplasty (TKA). This study aimed to compare operative time, length of stay, 30-day complications, and readmissions based on patient gender. METHODS: The prospectively collected National Surgical Quality Improvement Program registry from 2005 to 2014 was queried to identify primary elective THA and TKA patients. Multivariate regression was used to compare the rates of 30-day adverse events, rates of readmission, operative time, and postoperative length of stay between men and women. Multivariate analyses were controlled for baseline patient characteristics and procedure type. RESULTS: A total of 173,777 patients were included (63.5% TKA and 36.5% THA). Male gender increased the risk of multiple adverse events, including death (relative risk [RR] 1.1, P < .001), surgical site infection (RR 1.2, P < .001), sepsis (RR 1.4, P < .001), cardiac arrest (RR 1.8, P < .001), and return to the operating room (RR 1.3, P < .001). Men had decreased overall adverse events (RR 0.8, P < .001) secondary to a lower risk of urinary tract infection (RR 0.5, P < .001) and blood transfusion (RR 0.7, P < .001), which were prevalent adverse events. Men had an increased risk of 30-day readmission (RR 1.2, P < .001), slightly increased operative time (+6 minutes, P < .001), and slightly decreased length of stay (-0.2 days, P < .001). CONCLUSION: Men had increased risk of multiple individual adverse events including death, surgical site infection, cardiac arrest, return to the operating room, and readmission. Conversely, women had increased risk of urinary tract infection and blood transfusion.