Adoption of Robotic-Arm-Assisted Total Knee Arthroplasty Is Associated with Decreased Use of Articular Constraint and Manipulation under Anesthesia Compared to a Manual Approach
Haptic robotic-arm-assisted total knee arthroplasty (RATKA) seeks to leverage three-dimensional planning, intraoperative assessment of ligament laxity, and guided bone preparation to establish and achieve patient-specific targets for implant position. We sought to compare (1) operative details, (2) knee alignment, (3) recovery of knee function, and (4) complications during adoption of this technique to our experience with manual TKA. We compared 120 RATKAs performed between December 2016 and July 2018 to 120 consecutive manual TKAs performed between May 2015 and January 2017. Operative details, lengths of stay (LOS), and discharge dispositions were collected. Tibiofemoral angles, Knee Society Scores (KSS), and ranges of motion were assessed until 3 months postoperatively. Manipulations under anesthesia, complications, and reoperations were tabulated. Mean operative times were 22â€‰minutes longer in RATKA (pâ€‰<â€‰0.001) for this early cohort, but decreased by 27â€‰minutes (pâ€‰<â€‰0.001) from the first 25 RATKA cases to the last 25 RATKA cases. Less articular constraint was used to achieve stability in RATKA (93 vs. 55% cruciate-retaining, pâ€‰<â€‰0.001; 3 vs. 35% posterior stabilized (PS), pâ€‰<â€‰0.001; and 4 vs. 10% varus-valgus constrained, p_â€‰=â€‰_0.127). RATKA had lower LOS (2.7 vs. 3.4 days, pâ€‰<â€‰0.001). Discharge dispositions, tibiofemoral angles, KSS, and knee flexion angles did not differ, but manipulations were less common in RATKAs (4 vs. 17%, pâ€‰=â€‰0.013). We observed less use of constraint, shorter LOS, and fewer manipulations under anesthesia in RATKA, with no increase in complications. Operative times were longer, particularly early in the learning curve, but improved with experience. All measured patient-centered outcomes were equivalent or favored the newer technique, suggesting that RATKA with patient-specific alignment targets does not compromise initial quality. Observed differences may relate to improved ligament balance or diminished need for ligament release.
Correction to: Total knee arthroplasty in patients with lumbar spinal fusion leads to significant changes in pelvic tilt and sacral slope
Dual-mobility versus Fixed-bearing in Primary Total Hip Arthroplasty: Outcome Comparison
Purpose/UNASSIGNED:Use of dual mobility (DM) articulations can reduce the risk of instability in both primary and revision total hip arthroplasty (THA). Knowledge regarding the impact of this design on patient-reported outcome measures (PROMs) is limited. This study aims to compare clinical outcomes between DM and fixed bearing (FB) prostheses following primary THA. Materials and Methods/UNASSIGNED:All patients who underwent primary THA between 2011-2021 were reviewed retrospectively. Patients were separated into three cohorts: FB vs monoblock-D vs modular-DM. An evaluation of PROMs including HOOS, JR, and FJS-12, as well as discharge-disposition, 90-day readmissions, and revisions rates was performed. Propensity-score matching was performed to limit significant demographic differences, while ANOVA and chi-squared test were used for comparison of outcomes. Results/UNASSIGNED:=0.608) between the groups. Conclusion/UNASSIGNED:DM bearings yield PROMs similar to those of FB implants in patients undergoing primary THA. Although DM implants are utilized more often in patients at higher-risk for instability, we suggest that similar patient satisfaction may be attained while achieving similar dislocation rates.
Total knee arthroplasty in patients with lumbar spinal fusion leads to significant changes in pelvic tilt and sacral slope
BACKGROUND:The knee-hip-spine syndrome has been well elucidated in the literature in recent years. The aim of this study was to evaluate the effect of total knee arthroplasty (TKA) on spinopelvic sagittal alignment in patients with and without pre-TKA lumber spinal fusion. METHODS:This is a retrospective cohort study of 113 patients who underwent TKA for primary osteoarthritis. Patients were stratified into the following three groups: (1) patients who had pre-TKA spinal fusion (SF, nâ€‰=â€‰19), (2) patients who had no spinal fusion but experienced pre-TKA flexion contracture (FC, nâ€‰=â€‰20), and (3) patients without flexion contracture or spinal fusion before TKA (no SF/FC, nâ€‰=â€‰74). Spinopelvic sagittal alignment parameters, including pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL), thoracic kyphosis (TK), and plumb line-sacrum distance (SVA) were measured preoperatively and 3Â months postoperatively on lateral standing full-body low-dose images. RESULTS:TKA resulted in significant pre- to postoperative changes in pelvic tilt (average âˆ† PTâ€‰=â€‰-Â 8.6Â°, pâ€‰=â€‰0.018) and sacral slope (average âˆ† SSâ€‰=â€‰8.6Â°, pâ€‰=â€‰0.037) in the spinal fusion (SF) group. Non-significant changes in spinopelvic sagittal alignment parameters (PT, SS, LL, TK, SVA) were noted postoperatively in all patients in the FC and the no SF/FC groups. CONCLUSIONS:TKA can lead to meaningful changes in spinopelvic alignment in patients with prior lumbar fusion compared to those without spinal fusion. Patients with spinal fusion who are candidates for both hip and knee replacements should consider undergoing TKA first since changes in spinopelvic sagittal alignment can increase the risk of future complications. LEVEL III EVIDENCE/METHODS:Retrospective Cohort Study.
Presence of back pain prior total knee arthroplasty and its effects on short-term patient-reported outcome measures
PURPOSE/OBJECTIVE:Back pain may both decrease patient satisfaction after TKA and confound outcome assessment in satisfied patients. Our primary objective was to determine whether preoperative back pain is associated with differences in postoperative patient-reported outcome measures (PROMs). METHODS:We retrospectively reviewed 234 primary TKA patients who completed PROMs preoperatively and 12 weeks postoperatively, which included a back pain questionnaire, the Knee Injury and Osteoarthritis Outcome Score for Joint Replacement (KOOS JR) and the Forgotten Joint Score-12 (FJS-12). Cohorts were defined based on the severity of preoperative back pain (none, mild, moderate and severe) and compared. Demographics were compared using ANOVA and Chi-square analysis. Univariate ANCOVA analysis was utilized to compare PROMs while accounting for significant demographic differences. RESULTS:Both preoperative KOOS JR scores (none: 47.90, mild: 47.61, moderate: 44.61 and severe: 38.70; pâ€‰=â€‰0.013) and 12-week postoperative KOOS JR scores (none: 61.24, mild: 64.94, moderate: 57.48 and severe: 57.01; pâ€‰=â€‰0.012) had a statistically significant inverse relationship with regard to the intensity of preoperative back pain. Although FJS-12 scores at the 12-week postoperative period trended lower with increasing levels of preoperative back pain (pâ€‰=â€‰0.362), it did not reach statistical significance. Patients who reported severe back pain preoperatively achieved the largest delta improvement from baseline compared to those with lesser pain intensity (pâ€‰=â€‰0.003). Patients who had a 2-grade improvement in their back pain achieved significantly higher KOOS JR scores 12 weeks postoperatively compared to patients with either 1-grade or no improvement (63.53 vs. 55.98; pâ€‰=â€‰0.042). Both preoperative (47.99 vs. 41.11; pâ€‰=â€‰0.003) and 12-week postoperative (64.06 vs. 55.73; pâ€‰<â€‰0.001) KOOS JR scores were statistically higher for those who reported mild or no back pain pre-and postoperatively than those who reported moderate or severe back pain pre-and postoperatively. CONCLUSION/CONCLUSIONS:Knee pain and back pain both exert negative effects on outcome instruments designed to measure pain and function. Although mean improvement from pre- to postoperative KOOS JR scores for patients with severe pre-existing back pain was higher than their counterparts, this statistical difference is likely not clinically significant. This implies that all patients may experience similar benefits from TKA despite the presence or absence of back pain. Attempts to measure TKA outcomes using PROMs should seek to control for lumbago and other sources of body pain. Level of Evidence IIIRetrospective Cohort Study.
Equivalent VTE rates after total joint arthroplasty using thromboprophylaxis with aspirin versus potent anticoagulants: retrospective analysis of 4562 cases across a diverse healthcare system
BACKGROUND:Guidelines support aspirin thromboprophylaxis for primary total hip and knee arthroplasty (THA and TKA) but supporting evidence has come from high volume centers and the practice remains controversial. METHODS:We studied 4562 Medicare patients who underwent elective primary THA (1736, 38.1%) or TKA (2826, 61.9%) at 9 diverse hospitals. Thirty-day claims data were combined with data from the health system's electronic medical records to compare rates of venous thromboembolism (VTE) between patients who received prophylaxis with: (1) aspirin alone (47.3%), (2) a single, potent anticoagulant (29%), (3) antiplatelet agents other than aspirin or multiple anticoagulants (21.5%), or (4) low-dose subcutaneous unfractionated heparin or no anticoagulation (2.2%). Sub-analyses separately evaluating THA, TKA and cases from lower volume hospitals (nâ€‰=â€‰975) were performed. RESULTS:The 30-day VTE incidence was 0.6% (29/4562). VTE rates were equal in patients receiving aspirin and those receiving a single potent anticoagulant (0.5% in both groups). Patients with VTE were significantly older than patients without VTE (mean 76.5 vs. 73.1â€‰years, Pâ€‰=â€‰0.04). VTE rate did not associate with sex or hospital case volume. On bivariate analysis considering age, aspirin did not associate with greater VTE risk compared to a single potent anticoagulant (ORâ€‰=â€‰2.1, CIâ€‰=â€‰0.7-6.3) with the numbers available. Odds of VTE were increased with use of subcutaneous heparin or no anticoagulant (ORâ€‰=â€‰6.4, CIâ€‰=â€‰1.2-35.6) and with multiple anticoagulants (ORâ€‰=â€‰3.6, CIâ€‰=â€‰1.1-11.2). THA and TKA demonstrated similar rates of VTE (0.5% vs. 0.7%, respectively, Pâ€‰=â€‰0.43). Of 975 cases done at lower volume hospitals, 387 received aspirin, none of whom developed VTE. CONCLUSIONS:This study provides further support for aspirin as an effective form of pharmacological VTE prophylaxis after total joint arthroplasty in the setting of a multi-modal regimen using 30-day outcomes. VTE occurred in 0.7% of primary joint arthroplasties. Aspirin prophylaxis did not associate with greater VTE risk compared to potent anticoagulants in the total population or at lower volume hospitals.
ICD-10 Coding Mismatch in Computer and Robotic Assisted Primary Total Hip Arthroplasty
BACKGROUND:Revision Procedural Coding System (ICD-10-PCS) is a granular procedural classification system with the ability to precisely classify types of technology utilized in total hip arthroplasty (THA). However, coding nuances and the rapidly evolving nature of technology may lead to coding inaccuracies. The purpose of this study is to determine the accuracy of ICD-10-PCS coding in computer-navigated and robotic THA and discuss its implications on clinical data. METHODS:The arthroplasty database at a single institution was retrospectively reviewed for all primary computer and robotic assisted THAs performed between October 2015 to November 2020. The type of technology utilized was determined from the surgical record and compared with the ICD-10-PCS codes applied to each procedure. RESULTS:A total of 3721 technology-assisted THAs were identified and reviewed. 87.5% of technology-assisted THAs were coded with the correct type of technology. The most common error in computer navigated THA was the omission of the technology code, while the most common error in robotic assisted THA was the designation of codes for both computer navigation and robotic assistance. CONCLUSION/CONCLUSIONS:The granular nature of ICD-10-PCS allows for precise distinction between types of technology-assisted THA. However, rates of coding inaccuracy bring concern for the integrity of this data. The inaccuracy of ICD-10-PCS data is not insignificant and should bring concern for the validity of collective data sets that use it exclusively for its procedural granularity.
Early, Mid-Term, and Late-Term Aseptic Femoral Revisions After THA: Comparing Causes, Complications, and Resource Utilization
BACKGROUND:Registry data suggest increasing rates of early revisions after total hip arthroplasty (THA). We sought to analyze modes of failure over time after index THA to identify risk factors for early revision. METHODS:We identified 208 aseptic femoral revision THAs performed between February 2011 and July 2019 using an institutional database. We compared demographics, diagnoses, complications, and resource utilization between aseptic femoral revision THA occurring within 90 days (early), 91 days to 2 years (mid), and greater than 2 years (late) after index arthroplasty. RESULTS:Early revisions were 33% of revisions at our institution in the time period analyzed. Periprosthetic fractures were 81% of early, 27% of mid, and 21% of late femoral revisions (P < .01). Women were more likely to have early revisions than men (75% vs 53% of mid and 48% of late revisions; P < .01). Patients who had early revisions were older (67.97 Â± 10.06) at the time of primary surgery than those who had mid and late revisions (64.41 Â± 12.10 and 57.63 Â± 12.52, respectively, P < .01). Index implants were uncemented in 99% of early, 96% of mid, and 64% of late revisions (P < .01). Early revisions had longer postoperative length of stay (4.4 Â± 3.3) than mid and late revisions (3.0 Â± 2.2 and 3.7 Â± 2.1, respectively, PÂ = .02). In addition, 58% of early revisions were discharged to an inpatient facility compared with 36% of mid and 41% of late revisions (PÂ = .03). CONCLUSION/CONCLUSIONS:Early aseptic femoral revisions largely occur in older women with uncemented primary implants and primarily due to periprosthetic fractures. Reducing the incidence of periprosthetic fractures is critical to decreasing the large health care utilization of early revisions.
Sequencing of Circulating Microbial Cell-Free DNA Can Identify Pathogens in Periprosthetic Joint Infections
BACKGROUND:Over 1 million Americans undergo joint replacement each year, and approximately 1 in 75 will incur a periprosthetic joint infection. Effective treatment necessitates pathogen identification, yet standard-of-care cultures fail to detect organisms in 10% to 20% of cases and require invasive sampling. We hypothesized that cell-free DNA (cfDNA) fragments from microorganisms in a periprosthetic joint infection can be found in the bloodstream and utilized to accurately identify pathogens via next-generation sequencing. METHODS:In this prospective observational study performed at a musculoskeletal specialty hospital in the U.S., we enrolled 53 adults with validated hip or knee periprosthetic joint infections. Participants had peripheral blood drawn immediately prior to surgical treatment. Microbial cfDNA from plasma was sequenced and aligned to a genome database with >1,000 microbial species. Intraoperative tissue and synovial fluid cultures were performed per the standard of care. The primary outcome was accuracy in organism identification with use of blood cfDNA sequencing, as measured by agreement with tissue-culture results. RESULTS:Intraoperative and preoperative joint cultures identified an organism in 46 (87%) of 53 patients. Microbial cfDNA sequencing identified the joint pathogen in 35 cases, including 4 of 7 culture-negative cases (57%). Thus, as an adjunct to cultures, cfDNA sequencing increased pathogen detection from 87% to 94%. The median time to species identification for cases with genus-only culture results was 3 days less than standard-of-care methods. Circulating cfDNA sequencing in 14 cases detected additional microorganisms not grown in cultures. At postoperative encounters, cfDNA sequencing demonstrated no detection or reduced levels of the infectious pathogen. CONCLUSIONS:Microbial cfDNA from pathogens causing local periprosthetic joint infections can be detected in peripheral blood. These circulating biomarkers can be sequenced from noninvasive venipuncture, providing a novel source for joint pathogen identification. Further development as an adjunct to tissue cultures holds promise to increase the number of cases with accurate pathogen identification and improve time-to-speciation. This test may also offer a novel method to monitor infection clearance during the treatment period. LEVEL OF EVIDENCE/METHODS:Diagnostic Level II. See Instructions for Authors for a complete description of levels of evidence.
Consideration of pelvic tilt at the time of preoperative planning improves standing acetabular position after robotic-arm assisted total hip arthroplasty
INTRODUCTION/UNASSIGNED:Approximately half of dislocating total hip arthroplasties (THAs) demonstrate acetabular component position within traditional safe zones. It is unclear if postoperative functional acetabular position can be reliably improved by considering preoperative pelvic tilt. We investigated whether standing cup position targets could be more accurately achieved by considering preoperative standing pelvic tilt in addition to bone landmarks when planning for robot-assisted THA. METHODS/UNASSIGNED:We reviewed 146 THAs performed by a single surgeon using computed tomography-based 3-dimensional planning and robotic technology to guide acetabular reaming and component insertion. Planning for 73 consecutive cases started at 40Â° of inclination and 22Â° of anteversion relative to the supine functional plane and was adjusted to better match native hip anatomy. Planning for the next 73 cases was modified to consider standing pelvic position based on standing preoperative radiographs. We compared groups to determine the rate when cups were placed outside our standing targets of 15-30Â° anteversion and 35-50Â° inclination. RESULTS/UNASSIGNED:â€‰=â€‰0.352). The range of functional positions was narrower in the functional planning group: 35.7-47.5Â° versus 31.8-54.9Â° of inclination and 16.7-35.0Â° versus 10.1-35.9Â° of anteversion. DISCUSSION/UNASSIGNED:Our results suggest enhanced planning that considers pelvic tilt, when coupled to a precision tool to achieve the plan, can reliably achieve target standing component positions. Considering preoperative functional pelvic position may improve postoperative functional acetabular component placement in THA, but the clinical benefit of this has yet to be confirmed.