A Three-dimensional Comparison of Pre- and Post-component Position in a Series of Off-label Robotic-assisted Revision Total Knee Arthroplasties.

Background: The application of robotic-assisted arthroplasty in revision knee scenarios continues to evolve. This study compares the pre- and post-revision implant positions in series of revision total knee arthroplasties (TKA) using a robotic arm system. Methods: Twenty-five consecutive off-label robotic-assisted revision TKA were performed. After virtual revision femoral and tibial components were positioned to achieve "balanced" medial and lateral flexion and extension gaps, the existing primary implants (PI) were removed, and bone cuts were executed with the robotic arm system. Preoperative coronal, sagittal, and axial position of the PI was compared to the final planned positions of the robotic revision implants (RRI) for each subject. A repeated measures ANOVA using the absolute difference in millimeters and degrees between the PI and RRI orientation was completed. Results: Intra-operatively, the virtual gaps were balanced within the planning software followed by successful execution of the plan. There was a statistically significant difference between posterior condylar offset and tibial component positioning for RRI compared to PI. There was no difference between the distal femoral component values between PI and RRI. Conclusions: The sagittal alignment of the revision implants, specifically the femoral posterior condylar offset and tibial component slope, are statistically significant considerations for a stable revision TKA with off-label use of a robotic-arm system. Other potential benefits may include appropriate implant sizing which can affect the resultant ligamentous tension important for a functional revision TKA. Future research and software iterations will be needed to determine the overall accuracy and utility of robotic-assisted revision TKA.

Partial meniscectomy using needle arthroscopy associated with significantly less pain and improved patient reported outcomes at two weeks after surgery: A comparison to standard knee arthroscopy.

Purpose: to compare immediate post-operative pain and patient-reported outcomes (PROs) after partial meniscectomy with needle (NA) vs. standard (SA) arthroscopy technique. Methods: A retrospective review of a consecutive series of patients who underwent partial meniscectomy before and after adoption of a needle arthroscopic technique was performed. Meniscus repairs, root repairs, and those with ligamentous injuries were excluded. Total milligram morphine equivalents (MMEs) consumed, Visual analog scale (VAS) pain, and Knee Injury and Osteoarthritis Outcome Scores (KOOS) were compared pre-operatively and at 2 and 6-weeks postoperatively. Univariate analysis was used to compare results. Results: Nineteen patients were in each group (NA: 10 females, SA: 11 females). Mean ± SD age (NA 42.8 ± 8.4 vs. SA 47.6 ± 10.4 years, p = 0.13) and body mass index (NA 31.4 ± 5.6 vs. SA 35.1 ± 5.4 m/kg2, p = 0.06) were not significantly different. Seventeen (89%) patients in both groups had medial meniscus tears of the posterior horn. Preoperative Outerbridge score was significantly greater in the SA group (3.4 vs. 1.8, p = 0.002); however, preoperative VAS pain (NA 6.1 ± 1.7 vs. SA 6.1 ± 1.8, p = 0.98) and KOOS pain (NA 44 ± 17% vs. SA 37 ± 12.5%, p = 0.20) were similar. Amount of arthroscopic fluid used was significantly greater in the SA vs. NA group (1.4 ± 0.7 vs. 0.5 ± 0.3 L, p < 0.0001), but tourniquet time was equivalent (NA 20 ± 6 vs.16 ± 6 min, p = 0.11). VAS pain scores (NA 1.0 ± 1.1 vs. SA 2.6 ± 1.5, p = 0.0014), KOOS pain (NA 79 ± 15% vs. 58 ± 19%, p = 0.0006), and Quality of Life (QOL) scores (NA 70 ± 22% vs. SA 43 ± 24%, p = 0.001) were significantly better at 2-weeks post-op in the N group. By 6 weeks post-op, all PROs including VAS pain and KOOS scores were similar between groups. Conclusions: Adoption of a needle arthroscopic technique for partial meniscectomy was associated with significantly improved VAS and KOOS pain scores two-weeks post-operatively. Differences were not sustained at 6 weeks after surgery. Level of evidence: III, Retrospective Comparison Study.

Early and Direct Rehab Transfer Leads to Significant Cost Savings and Decreased Hospital Length of Stay for Total Joint Arthroplasty in a Veteran Population.

BACKGROUND: Total joint arthroplasty is the most common elective orthopedic procedure in the Veterans Affairs hospital system. In 2019, physical medicine and rehabilitation began screening patients before surgery to select candidates for direct transfer to acute rehab after surgery. The primary outcome of this study was to demonstrate that the accelerated program was successful in decreasing inpatient costs and length of stay (LOS). The secondary outcome was to show that there was no increase in complication, reoperation, and readmission rates. METHODS: A retrospective review of total joint arthroplasty patients was conducted with three cohorts: 1) control (n = 193), 2) transfer to rehab orders on postop day #1 (n = 178), and 3) direct transfers to rehab (n = 173). To assess for demographic disparities between cohorts, multiple analysis of variance tests followed by a Bonferroni P-value correction were used. Differences between test groups regarding primary outcomes were assessed with analysis of variance tests followed by pairwise t-tests with Bonferroni P-value corrections. RESULTS: There were no significant differences between the cohort demographics or comorbidities. The mean total LOS decreased from 7.0 days in the first cohort, to 6.9 in the second, and 6.0 in the third (P = .00034). The mean decrease in cost per patient was $14,006 between cohorts 1 and 3, equating to over $5.6 million in savings annually. There was no significant change in preintervention and postintervention short-term complications (P = .295). CONCLUSIONS: Significant cost savings and decrease in total LOS was observed. In the current health care climate focused on value-based care, a similar intervention could be applied nationwide to improve Veterans Affair services.

Analysis of Preoperative Screening Criteria for Total Joint Arthroplasty in a Veteran Population.

BACKGROUND: This study describes the experience of patients who initially failed total joint arthroplasty preoperative screening criteria but were subsequently optimized and underwent surgery. METHODS: Time to optimization from the patients' initial clinic visit was recorded. Following surgery, patients' body mass index and lab work were tracked to determine whether they "relapsed" to their preoptimized state. Descriptive statistics determined (1) the length of time to meet screening criteria and (2) which screening criteria took the longest to optimize. RESULTS: Only 11 of 84 patients (13%) required greater than 1 year to meet criteria. Most patients (76%) "relapsed" to their previous nonqualifying status after surgery; however, this reversion did not contribute significantly to an increased rate of complication in short-term follow-up (P = .4298). CONCLUSION: Patients in this study were able to achieve preoperative screening criteria for total joint arthroplasty in less than 1 year. Relapsing after surgery does not appear to adversely affect clinical outcomes.

Early Experience and Results Using Patient-Reported Outcomes Measurement Information System Scores in Primary Total Hip and Knee Arthroplasty.

BACKGROUND: Our study determined if preoperative Patient-Reported Outcomes Measurement Information System (PROMIS) scores could predict achieving minimum clinically important differences (MCIDs) in postoperative PROMIS scores after primary total hip and knee arthroplasty. METHODS: Ninety-three patients were administered the PROMIS Depression, Pain Interference, and Physical Function domains at their preoperative appointment and 6-week follow-up visit. MCIDs were drawn from existing literature for the PROMIS domains. RESULTS: The MCID was achieved in 74% of patients for Pain Interference, 34% for Physical Function, and 24% for Depression. Our model could predict with 90% specificity which patients would meet MCID if their preop PROMIS Pain score was above 38, Physical Function score less than 19, or Depression score above 22. CONCLUSION: Preoperative PROMIS Pain Interference, Physical Function, and Depression scores can predict achieving MCID in postoperative PROMIS scores.

Significant increase in IgG4+ plasma cells in gastric biopsy specimens from patients with pernicious anaemia.

AIM: To investigate the presence of IgG4+ plasma cells in gastric mucosal biopsy samples from patients with atrophic gastritis (AG) and a history of pernicious anaemia (PA) (AG+PA+). METHODS: Gastric mucosal biopsy specimens from 46 patients with AG+PA+ were investigated. As controls, we evaluated specimens from patients with AG but no history of PA (AG+ PA-) (n=25), normal histology (n=25), mild chronic inactive gastritis (MCIG) (n=25) or Helicobacter pylori gastritis (HP) (n=25). IgG4+ plasma cells were detected by two immunohistochemical methods: (1) using a monoclonal antibody, the average of the three most cellular high-power fields was counted in areas with the highest density of IgG4+ plasma cells; (2) using a dual-chromagen stain for both IgG4 and CD138 (plasma cell marker), the number of IgG4+ cells per 200 CD138+ plasma cells was counted. The latter was used to ensure that the number of IgG4+ cells was not simply related to the degree of inflammation (density of plasma cells). RESULTS: Identical results were obtained with the two staining methods. Increased numbers of IgG4+ plasma cells were present in 37% of patients with AG+PA+, but in none with AG+PA-, MCIG, HP or normal gastric biopsy results (100% specific, p=0.0001). CONCLUSION: IgG4+ plasma cells may play a role in the pathogenesis of PA and may be a useful marker for its diagnosis.

Competitive advantage on a warming planet.

Whether you're in a traditional smokestack industry or a "clean" business like investment banking, your company will increasingly feel the effects of climate change. Even people skeptical about global warming's dangers are recognizing that, simply because so many others are concerned, the phenomenon has wide-ranging implications. Investors already are discounting share prices of companies poorly positioned to compete in a warming world. Many businesses face higher raw material and energy costs as more and more governments enact policies placing a cost on emissions. Consumers are taking into account a company's environmental record when making purchasing decisions. There's also a burgeoning market in greenhouse gas emission allowances (the carbon market), with annual trading in these assets valued at tens of billions of dollars. Companies that manage and mitigate their exposure to the risks associated with climate change while seeking new opportunities for profit will generate a competitive advantage over rivals in a carbon-constrained future. This article offers a systematic approach to mapping and responding to climate change risks. According to Jonathan Lash and Fred Wellington of the World Resources Institute, an environmental think tank, the risks can be divided into six categories: regulatory (policies such as new emissions standards), products and technology (the development and marketing of climate-friendly products and services), litigation (lawsuits alleging environmental harm), reputational (how a company's environmental policies affect its brand), supply chain (potentially higher raw material and energy costs), and physical (such as an increase in the incidence of hurricanes). The authors propose a four-step process for responding to climate change risk: Quantify your company's carbon footprint; identify the risks and opportunities you face; adapt your business in response; and do it better than your competitors.