INTRODUCTION Capsular soft tissue is believed to be crucial to avoid instability events preceding impingement, a common reason for failure. Assessment of capsular contribution to stability after THA is limited by the inherent need of capsule dissection. Our goal was to develop a capsule-sparring cadaveric THA implantation model for experimental testing using off-the-shelf implants. METHODS Four bilateral cadaveric specimens underwent THA: intrapelvic THR on one side and DAA on the other. Pre- and postoperative CT scans were used to determine the final position of DAA THA components. All hips later underwent testing on a six degree-of-freedom robotic manipulator. Anterior and posterior capsules were tested by rotating the femur to impingement at clinically relevant at-risk positions. RESULTS Intrapelvic implantation of the components achieved high accuracy with acetabular cup inclination and anteversion as well as femoral stem varus/valgus and combined anteversion. Anterior hip capsule torque was greater in intrapelvic specimen than in DAA specimen as to be expected considering the anterior capsule is inherently compromised during a DAA THA. Similar torque at impingement was observed in the posterior region of the capsule between both groups. DISCUSSION These results suggest that component positioning can controlled, and soft tissue structures and tension can be maintained during the intrapelvic procedure. This technique enables future investigation of ligament contributions without the inherent limitations of a compromised capsule seen in previous biomechanical hip studies.
BACKGROUND:Shear forces on the patella can lead to patellar loosening and failure in total knee arthroplasty (TKA). Our objectives were as follows: (1) evaluate the mechanical load-to-shear failure in a unique cohort of cemented patellar components in well-functioning postmortem TKAs and (2) determine the influence of clinical and radiographic factors on load-to-shear failure. METHODS:There were 22 patellae that were harvested from well-functioning postmortem TKAs (mean implantation duration 9.1 years [range, 1.7 to 19.6]). There were three all-polyethylene 3-peg onlay patellar designs evaluated. The patellae were evaluated for polyethylene damage, implant-to-bone size ratios, microarchitectural parameters, and implant-cement-bone interface. Patellar specimens were loaded with isolated shear stress using a servo-hydraulic test frame until failure. Univariate and multivariable linear regression models were used to analyze the influence of clinical and radiographic factors on load-to-shear failure. RESULTS:The mean load-to-shear failure was 1,881 ± 621 N. There were nine patellae that failed at the bone-cement interface, seven that failed at the implant-cement interface, and six that involved both interfaces. There were no failures at the peg-implant junction. On multivariable analyses, load to failure was positively associated with bone volume fraction and negatively associated with body mass index, duration of implantation, and implant-to-bone surface area coverage. Load-to-shear failure was not associated with surface damage or radiographic parameters and did not differ across the three patellar implant designs. CONCLUSIONS:In this novel cohort of cemented patellar buttons from well-functioning postmortem TKAs, load-to-shear failure was higher than previously reported in buttons cemented in cadaver native patellae. The amount of bony coverage by the patellar button was inversely associated with shear strength after accounting for other pertinent factors. When choosing between two patellar button sizes, surgeons should consider opting for the smaller size, which may improve the maximum shear strength of the patellar construct.
BACKGROUND:At our institution, surgeons were observing cases of failed total knee arthroplasties (TKAs) with surface delamination of the tibial insert fabricated by direct compression molding. The increase in unexpected failure led us to investigate the prevalence of delamination and its causes through the use of retrieval analysis and reviews of clinical, demographic, and radiographic data. METHODS:Between 2000 and 2019, a total of 519 Exactech Optetrak posterior-stabilized direct-compression-molded polyethylene inserts had been retrieved. To determine prevalence, we utilized institutional usage data, manufacturer sales to our institution, and hospital records to determine the delamination rate. Eighty-six retrieved specimens (16 with delamination) were assessed for oxidation with use of infrared spectroscopy. RESULTS:Sixty-four (12%) of the 519 inserts had delamination. The delamination rate was 0.36% across the 20-year period. Osteolysis was the reason for revision in 25% of delaminated cases, compared with 4% of non-delaminated cases. The mean oxidation index of the delaminated inserts was 2.67 ± 1.4 (range, 1.2 to 6.6). Delamination was not associated with surgical factors (cement viscosity and tibial insert thickness) or processes associated with manufacturing and implantation of the inserts into the patients (implantation year, shelf life, and packaging and sterilization dates). CONCLUSIONS:The lack of causative factors for the increase in delamination was perplexing. In 2021, following the completion of our study, the manufacturer determined that since 2004, polyethylene inserts were packaged in "non-conforming" vacuum bags that were missing a secondary barrier layer intended to markedly lessen oxygen permeation. The use of non-conforming bags apparently increased the risk of premature oxidation, delamination, and associated osteolysis. LEVEL OF EVIDENCE:Prognostic Level IV . See Instructions for Authors for a complete description of levels of evidence.
BACKGROUND:Prosthetic impingement after total hip arthroplasty (THA) has been associated with instability and may be a cause of accelerated polyethylene wear and pain. Previous retrieval studies report a high prevalence of impingement in acetabular liners. Robotic technology has the potential to reduce THA instability as it enables technical precision and optimizes implant positioning. However, whether robotics can improve impingement prevalence is unknown. Thus, the objectives of this study were to: (1) determine the prevalence and severity of acetabular liner impingement with robotic navigation; and (2) compare impingement prevalence with a control cohort of manually placed THA liners. METHODS:There were 18 robotic-assisted liners and 11 non-robotic controls scored for the presence and severity of impingement. Radiographic measurements of acetabular inclination and anteversion were assessed using prerevision standing radiographs. Femoral head size (36 being the most common), length of implantation, revision indication, age, gender, and body mass index were recorded. RESULTS:Of the robotic liners, 61% showed impingement, while 45% of the non-robotic liners showed impingement (P = 0.14). The robotic group demonstrated a lower variance of inclination (robotic: 41.7° ± 3.9, control: 42.8° ± 7.1, P = 0.64) and lower anteversion variance (robotic: 22.8° ± 2.8, control: 20.8° ± 7.9, P = 0.43), but mean values did not differ between the groups. Impingement presence and severity were not related to head size, length of implantation, or other demographic variables. CONCLUSIONS:This study suggests that the use of robotic-assisted technology employing modern-day implants with larger diameter heads does not reduce the prevalence or severity of prosthetic impingement in retrieved acetabular liners from revision THA.
Competitive dancers represent a unique patient population in the setting of hip arthroplasty given the high degree of hip strength and mobility required by their profession. We sought to determine the clinical outcomes and ability to return to competitive dance after total hip arthroplasty (THA) or hip resurfacing arthroplasty (HRA) among competitive dancers. Active competitive dancers who underwent primary THA or HRA at a single institution with minimum one-year follow-up were included in the study. Primary outcomes included (1) the rate of return to competitive dance, (2) three PROMs (modified Harris Hip Score [mHHS], Hip Disability and Osteoarthritis Outcome Score for Joint Replacement [HOOS-JR], and Lower Extremity Activity Scale [LEAS]), and (3) post-operative complications. Forty-nine hips in 39 patients (mean age 56±13 years; 80% female) were included. Mean follow-up was 4.9±5.1 years. Thirty-seven THAs and 12 HRAs were performed. Ninety-six percent of patients returned to competitive dance activities post-operatively. With respect to PROMs, there were statistically significant improvements in mHHS, HOOS-JR, and LEAS from baseline to ≥ 1 year post-operatively. There were complications in 9/49 (18%) hips post-operatively, five (10%) of which required revision surgery. Active competitive dancers experienced significant improvements in functional outcome scores after THA or HRA, with a rate of return to competitive dance of 96%.
BACKGROUND:Modular connections in total hip arthroplasty (THA) offer surgical advantages, but can contribute to implant fretting and corrosion due to micromotion at the head-stem interface. Previous studies implicated lower flexural rigidity as a key contributing factor to THA corrosion and fretting, but none associated flexural rigidity with direct histological evaluation or magnetic resonance imaging (MRI) outcomes. The purpose of this study was to determine how implant flexural rigidity is associated with MRI imaging metrics and histopathological outcomes in patients who have a failed THA. METHODS:Patients requiring revision THA surgery underwent preoperative MRIs with 3-dimensional multispectral imaging techniques to suppress metal artifacts. The MRI images were graded for adverse local tissue reactions. For each hip, trunnion flexural rigidity was measured from the retrieved femoral stem, and a periprosthetic tissue sample was retrieved and evaluated using semiquantitative histology. Generalized linear models and analyses of variance were used to assess associations between flexural rigidity and MRI and histology outcomes. RESULTS:A total of 106 THA stems were retrieved (46 women and 60 men, age: 68 years (range, 60 to 73 years). After adjustment for length of implantation, flexural rigidity was negatively correlated with histologic aseptic lymphocyte-dominant vasculitis-associated lesion severity (β = -26.27, P = .018), Fujishiro lymphocyte grading (β = -13.4, P = .039), perivascular lymphocyte layers (β = -17.8, P = .022), the grade of tissue organization (β = -22.5, P = .009), the presence of diffuse synovitis (β = -66.5, P = .003), and the presence of lymphoid aggregates (β = -75.9, P = .022). No association was found between MRI metrics and flexural rigidity. CONCLUSIONS:Among these implants, decreased trunnion stiffness was associated with increased histologic features of adverse host-mediated soft tissue reactions.
BACKGROUND:Optimal analgesic protocols for total knee arthroplasty (TKA) patients remain controversial. Multimodal analgesia is advocated, often including peripheral nerve blocks and/or periarticular injections (PAIs). If 2 blocks (adductor canal block [ACB] plus infiltration between the popliteal artery and capsule of the knee [IPACK]) are used, also performing PAI may not be necessary. This noninferiority trial hypothesized that TKA patients with ACB + IPACK + saline PAI (sham infiltration) would have pain scores that were no worse than those of patients with ACB + IPACK + active PAI with local anesthetic. METHODS:A multimodal analgesic protocol of spinal anesthesia, ACB and IPACK blocks, intraoperative ketamine and ketorolac, postoperative ketorolac followed by meloxicam, acetaminophen, duloxetine, and oral opioids was used. Patients undergoing primary unilateral TKA were randomized to receive either active PAI or control PAI. The active PAI included a deep injection, performed before cementation, of bupivacaine 0.25% with epinephrine, 30 mL; morphine; methylprednisolone; cefazolin; with normal saline to bring total volume to 64 mL. A superficial injection of 20 mL bupivacaine, 0.25%, was administered before closure. Control injections were normal saline injected with the same injection technique and volumes. The primary outcome was numeric rating scale pain with ambulation on postoperative day 1. A noninferiority margin of 1.0 was used. RESULTS:Ninety-four patients were randomized. NRS pain with ambulation at POD1 in the ACB + IPACK + saline PAI group was not found to be noninferior to that of the ACB + IPACK + active PAI group (difference = 0.3, 95% confidence interval [CI], [-0.9 to 1.5], P = .120). Pain scores at rest did not differ significantly among groups. No significant difference was observed in opioid consumption between groups. Cumulative oral morphine equivalents through postoperative day 2 were 89 ± 40 mg (mean ± standard deviation), saline PAI, vs 73 ± 52, active PAI, P = .1. No significant differences were observed for worst pain, fraction of time in severe pain, pain interference, side-effects (nausea, drowsiness, itching, dizziness), quality of recovery, satisfaction, length of stay, chronic pain, and orthopedic outcomes. CONCLUSIONS:For TKA patients given a comprehensive analgesic protocol, use of saline PAI did not demonstrate noninferiority compared to active PAI. Neither the primary nor any secondary outcomes demonstrated superiority for active PAI, however. As we cannot claim either technique to be better or worse, there remains flexibility for use of either technique.
AimsThe primary aim of this prospective, multicentre study is to describe the rates of returning to golf following hip, knee, ankle, and shoulder arthroplasty in an active golfing population. Secondary aims will include determining the timing of return to golf, changes in ability, handicap, and mobility, and assessing joint-specific and health-related outcomes following surgery.MethodsThis is a multicentre, prospective, longitudinal study between the Hospital for Special Surgery, (New York City, New York, USA) and Edinburgh Orthopaedics, Royal Infirmary of Edinburgh, (Edinburgh, UK). Both centres are high-volume arthroplasty centres, specializing in upper and lower limb arthroplasty. Patients undergoing hip, knee, ankle, or shoulder arthroplasty at either centre, and who report being golfers prior to arthroplasty, will be included. Patient-reported outcome measures will be obtained at six weeks, three months, six months, and 12 months. A two-year period of recruitment will be undertaken of arthroplasty patients at both sites.ConclusionThe results of this prospective study will provide clinicians with accurate data to deliver to patients with regard to the likelihood of return to golf and timing of when they can expect to return to golf following their hip, knee, ankle, or shoulder arthroplasty, as well as their joint-specific functional outcomes. This will help patients to manage their postoperative expectations and plan their postoperative recovery pathway.Cite this article: Bone Jt Open 2023;4(7):490–495.
Background: Modular dual mobility (MDM) acetabular component use is rising in total hip arthroplasty. However, concern of mechanically assisted crevice corrosion (MACC) at the shell-liner interface remains. We investigated shell-liner corrosion using retrieval analyses and corrosion chamber testing. Methods: We analyzed fretting and corrosion on 10 matched pairs of 2 commercial MDM constructs (MDM1 and MDM2). Also, pristine pairs of Ti6Al4V shells and CoCrMo liners from 3 commercial dual mobility systems (MDM1, MDM2, and MDM3) were tested in vitro to model MACC performance. Three pairs of each were placed into an electrochemical chamber with stepwise increasing cyclic compression loads while measuring currents generated at the shell-liner taper. Onset fretting loads and fretting currents were calculated. Results: Corrosion damage scores on retrieved components were low but higher in the MDM2 to MDM1 liners (P = .006), specifically outside the taper region (P = .00003). Fretting currents were higher in the MDM2 than in MDM1 or MDM3 (P = .011). Onset loads were also higher in the MDM2 (P = .001). Conclusion: Among retrieved liners, MDM2 tapers seem prone to non-mechanical corrosion modes. Higher onset loads and fretting currents in MDM2 tapers indicate greater MACC resistance but higher severity once corrosion begins. Differences among the devices were likely due to taper design and surface finish. Currents in all 3 were <5 mu A, much lower than those observed with head-neck tapers. Our findings suggest that, among the types of corrosion observed in these MDM designs, mechanically driven corrosion may not be the most significant. (c) 2023 Elsevier Inc. All rights reserved.
BACKGROUND:The wide variety of patient-reported outcome measures used to assess outcomes following total joint arthroplasty can present a substantial methodological obstacle when attempting to compare information across studies or between institutions. A simple solution is to create crosswalks that reliably convert scores between patient-reported outcome measures. Our goal is to create and validate crosswalks between the commonly used Western Ontario & McMaster Universities Osteoarthritis Index (WOMAC) and short-form versions of the Hip Disability and Osteoarthritis Outcome Score Joint Replacement (HOOS JR)/Knee Injury and Osteoarthritis Outcome Score (KOOS JR.).METHODS:Patients in our joint replacement registry were included if they underwent primary total hip arthroplasty (n = 4649) or total knee arthroplasty (n = 3750) for osteoarthritis between May 2007 and February 2012. We used their preoperative and 2-year postoperative HOOS scores (n = 6351) or KOOS scores (n = 4688) to generate the patients' WOMAC and HOOS JR/KOOS JR scores. The equipercentile equating method was applied to create 10 crosswalks: HOOS JR/KOOS JR to WOMAC Total (WOMAC-T), and WOMAC-T, WOMAC Pain (WOMAC-P), WOMAC Stiffness (WOMAC-S), and WOMAC Function (WOMAC-F) to HOOS JR/KOOS JR. Crosswalk validity was assessed by comparing actual and derived scores using Spearman's rank correlation coefficients in a bootstrapped cohort.RESULTS:All 10 crosswalks showed strong positive correlations ranging from 0.846 (WOMAC-S to KOOS JR) to 0.981 (HOOS JR to WOMAC-T).CONCLUSION:We created and validated 10 crosswalks between WOMAC and HOOS JR/KOOS JR. We recommend using the crosswalks between WOMAC-T and HOOS JR/KOOS JR when possible, as they demonstrated the highest correlation. WOMAC-F or WOMAC-P should be used in favor of WOMAC-S if only subscores are available. The HOOS JR/KOOS JR should only be converted to a WOMAC-T.LEVEL OF EVIDENCE:Level III.
BackgroundDuloxetine, a serotonin-norepinephrine dual reuptake inhibitor, may improve analgesia after total knee arthroplasty (TKA). Previous studies had one primary outcome, did not consistently use multimodal analgesia, and used patient-controlled analgesia devices, potentially delaying discharge. We investigated whether duloxetine would reduce opioid consumption or pain with ambulation.MethodsA total of 160 patients received 60 mg duloxetine or placebo daily, starting from the day of surgery and continuing 14 days postoperatively. Patients received neuraxial anesthesia, peripheral nerve blocks, acetaminophen, nonsteroidal anti-inflammatory drugs, and oral opioids as needed. The dual primary outcomes were Numeric Rating Scale (NRS) scores with movement on postoperative days 1, 2, and 14, and cumulative opioid consumption surgery through postoperative day 14.ResultsDuloxetine was noninferior to placebo for both primary outcomes and was superior to placebo for opioid consumption. Opioid consumption (mean ± SD) was 288 ± 226 mg OME [94, 385] vs 432 ± 374 [210, 540] (duloxetine vs placebo) P = .0039. Pain scores on POD14 were 4.2 ± 2.0 vs 4.8 ± 2.2 (duloxetine vs placebo) P = .018. Median satisfaction with pain management was 10 (8, 10) and 8 (7, 10) (duloxetine vs placebo) P = .046. Duloxetine reduced interference by pain with walking, normal work, and sleep.ConclusionThe 29% reduction in opioid use corresponds to 17 fewer pills of oxycodone, 5 mg, and was achieved without increasing pain scores. Considering the ongoing opioid epidemic, duloxetine can be used to reduce opioid usage after knee arthroplasty in selected patients that can be appropriately monitored for potential side effects of the medication.
BackgroundMobile bearing designs are intended to reduce wear, but mixed results were reported from retrieval analyses. Postmortem evaluation (PM) provides the opportunity to assess polyethylene damage in successful implants. We compared damage patterns, MRI presentation, and histology between mobile-bearing and fixed tibial inserts retrieved postmortem and compared these results to our prior findings from implants retrieved at revision.MethodsEleven postmortem knees with rotating platform (RP) implants and 13 with fixed bearing (FB) implants were examined. All were MRI scanned, and tissue samples were collected from standardized regions for histology. Polyethylene inserts were subjectively scored to assess articular, backside, and PS post surfaces for damage modes and severity.ResultsAverage duration of implantation was 9.3 years (1.7-19.6 years). Surface burnishing was the most common polyethylene damage mode. Average damage scores were higher for RP (53.4) compared to FB inserts (34.4) due to greater backside damage (13.4 for RP vs 1.4 for FB). A minimal difference in damage was observed on the articular surfaces (37.4 RP vs 30.0 FB). Mild innate macrophage reactions were seen in 8 (72.7%) RP and 5 (45.5%) FB specimens. Polyethylene particles were identified in 7 (63.6%) RP and 3 (27.7%) FB specimens.ConclusionsPostmortem inserts showed low damage levels and mild tissue reactions compared to those reported for implants removed at revision arthroplasty. Nonetheless, trends in comparing RP and FB inserts were consistent with those seen in retrieval analyses, demonstrating the usefulness of retrieval studies in capturing performance differences among TKA designs.
Background: In response to the opioid epidemic, our arthroplasty service sequentially reduced the opioid quantities prescribed at primary total knee arthroplasty (TKA) discharge. However, its effect on post-discharge pain control and rehabilitation is unknown. We assessed if this decrease was associated with an increase in the risk of manipulation under anesthesia (MUA). Methods: We retrospectively reviewed 8799 patients undergoing primary TKA from 2016 to 2019 at a single institution. There were two institution-wide reductions in the amount of opioids prescribed at discharge; therefore, we divided patients into 3 periods (P1, P2, and P3). The mean discharge morphine milligram equivalents (MMEs) went from 900 MMEs to similar to 525 MMEs to similar to 320 MMEs in P1, P2, and P3, respectively. We analyzed MUA rates and if lower discharge MMEs was a risk factor for MUA in a multivariate model. We also compared refill patterns (rates, number, refill MMEs, and total MMEs) between MUA and non-MUA patients. Results: The rate of MUA did not increase with reduced discharged opioids (5.5% in P1, 5.8% in P2, and 4.6% in P3, P = .74). In a multivariate analysis, discharge MMEs of <450 was not a significant risk factor for MUA. However, a diagnosis of chronic pain (OR = 1.86, P <.001) and an elevated body mass index (OR = 1.02 per unit increase, P <.001) were significant risk factors. We did not find significant differences in any opioid prescription refill patterns in MUA and non-MUA patients. Conclusion: Serial reductions in discharge MMEs after primary TKA did not significantly affect the rate of MUA, a surrogate marker for pain control and the rehabilitative process. (C) 2021 Elsevier Inc. All rights reserved.
Recent investigations have confirmed the impact of spinopelvic mobility upon functional acetabular position. However, it is critical to remember the impact of femoral component position as it contributes to combined version of the hip joint. It has been demonstrated that implant position can affect articular wear, the potential for prosthetic impingement as well as a cause of joint instability. Ensuring an impingement-free range of motion at the time of hip replacement is critical to long-term survivorship. During hip reconstruction, there is significant latitude in acetabular component positioning but femoral component version is often dictated by native femoral anatomy and in some instances cannot be adjusted. Understanding the role that femoral version plays in prosthetic hip joint kinematics should provide surgeons with a better understanding of this complex relationship.
Background Multiple stakeholders are interested in improving patient experience after primary total hip arthroplasty due to shifts toward patient-centered care. Patient free-text narratives are a potentially valuable but largely unexplored source of data. Methods The records of 383 patients who underwent primary total hip arthroplasty between August 2016 and August 2019 were combined with vendor-supplied patient satisfaction data, which included patient free-text comments and the Press Ganey satisfaction survey. A total of 1295 patient comments were analyzed for sentiment, and negative comments were categorized into nine themes. Postoperative outcomes, patient-reported outcome measures, and traditional measures of satisfaction were compared between patients who provided a negative comment vs those who did not. Multivariable regression was used to determine perioperative variables associated with providing a negative comment. Results Of the 1295 patient comments: 54% were positive, 24% were negative, 10% were mixed, and 12% were neutral. Top two themes of negative comments were room condition (25%) and inefficient communication (23%). There were no differences in studied outcomes (eg. peak pain intensity, length of stay, or improvements in hip injury and osteoarthritis outcome scores Jr. and pain visual analog scale scores at 6-week follow-up) between those who provided negative comments vs those who did not (P > .05). However, patients who made negative comments were less likely to recommend their hospital care to peers (P < .001). Finally, patients who had >2 allergies (P = .024) were more likely to provide negative comments. Conclusion The present study demonstrates that patient satisfaction appears not to be a reliable sole proxy for traditional objective outcome measures of pain relief and functional improvement.
Objective: We measured the seroprevalence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) immunoglobulin G (IgG) antibodies among surgeons and anesthesiologists and associated antibody status with coronavirus disease 2019 (COVID-19) clinical illness. Methods: A cross-sectional study of SARS-CoV-2 IgG seroprevalence with a survey assessing demographics, SARS-CoV-2 exposure risk, and COVID-19 illness. The primary outcome was the period prevalence of SARS-CoV-2 IgG antibodies associated with COVID-19 illness. Results: One hundred forty three surgeons and anesthesiologists completed both serology and survey testing. We found no significant relationships between antibody status and clinical role (anesthesiologist, surgeon), mode of commuting to work, other practice settings, or place of residence. SARS-CoV-2 IgG seroprevalence was 9.8%. Positive IgG status was highly correlated with presence of symptoms of COVID-19 illness. Conclusions: These results suggest the relative safety of surgeons and anesthesiologists where personal protective equipment (PPE) is available and infection control protocols are implemented.
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. (C) 2021 Elsevier Inc. All rights reserved.
Background: This study examined a cohort of retrieved rotating hinge (RH) total knee arthroplasty implants of four different designs with emphasis on the surface damage observed on the polyethylene components. Our purpose was to determine if differences in polyethylene damage existed among the designs, and if those differences could be explained by differences in design characteristics. Materials and Methods: Seventy-two RH implants from four manufacturers (DePuy LPS/SROM, Zimmer NexGen, Stryker Howmedica MRH, and Biomet Finn-OSS) removed at the time of revision performed between 2002 and 2017 were identified in our institutional retrieval registry. Damage to the surfaces of the polyethylene was assessed using a subjective grading system and evaluated in multiple zones. Design characteristics that were evaluated included the following: location of the dwell point on the polyethylene component, posterior position of the axle, and amount of hyperextension and rotation allowed by the implant. Results: There were no differences in total damage scores between the four implant groups (P = .45). The Stryker Howmedica MRH group showed the least backside wear of all implants but significantly more articular-sided wear compared with two of the other three groups. All implants except NexGen showed increased total damage scores in implants revised for mechanical (vs nonmechanical) reasons and in implants with a longer duration of implantation. Conclusion: No single implant design emerged as superior in terms of minimizing polyethylene wear damage. Polyethylene damage existed in various locations but was not different in severity across designs, suggesting that there is no clear superior RH design that minimizes overall articular surface wear compared with other designs. (C) 2021 Elsevier Inc. All rights reserved.
AIMS:Due to the opioid epidemic in the USA, our service progressively decreased the number of opioid tablets prescribed at discharge after primary hip (THA) and knee (TKA) arthroplasty. The goal of this study was to analyze the effect on total morphine milligram equivalents (MMEs) prescribed and post-discharge opioid repeat prescriptions.METHODS:We retrospectively reviewed 19,428 patients undergoing a primary THA or TKA between 1 February 2016 and 31 December 2019. Two reductions in the number of opioid tablets prescribed at discharge were implemented over this time; as such, we analyzed three periods (P1, P2, and P3) with different routine discharge MME (750, 520, and 320 MMEs, respectively). We investigated 90-day refill rates, refill MMEs, and whether discharge MMEs were associated with represcribing in a multivariate model.RESULTS:A discharge prescription of < 400 MMEs was not a risk factor for opioid represcribing in the entire population (p = 0.772) or in opioid-naïve patients alone (p = 0.272). Procedure type was the most significant risk factor for narcotic represcribing, with unilateral TKA (hazard ratio (HR) = 5.62), bilateral TKA (HR = 6.32), and bilateral unicompartmental knee arthroplasty (UKA) (HR = 5.29) (all p < 0.001) being the highest risk for refills. For these three procedures, there was approximately a 5% to 6% increase in refills from P1 to P3 (p < 0.001); however, there was no significant increase in refill rates after any hip arthroplasty procedures. Total MMEs prescribed were significantly reduced from P1 to P3 (p < 0.001), leading to the equivalent of nearly 500,000 fewer oxycodone 5 mg tablets prescribed.CONCLUSION:Decreasing opioids prescribed at discharge led to a statistically significant reduction in total MMEs prescribed. While the represcribing rate did not increase for any hip arthroplasty procedure, the overall refill rates increased by about 5% for most knee arthroplasty procedures. As such, we are now probably prescribing an appropriate amount of opioids at discharge for knee arthroplasty procedure, but further reductions may be possible for hip arthroplasty procedures. Cite this article: Bone Joint J 2021;103-B(7 Supple B):103-110.