The Management of Aneurysmal Degeneration of Lower Extremity Cryopreserved Saphenous Vein Bypass Grafts.

BACKGROUND: The use of cryopreserved saphenous veins (CSVs) for the treatment of lower extremity peripheral arterial disease is an attractive option when there is no available autogenous vein. Prior studies found CSVs are at risk for aneurysmal degeneration requiring reoperation. As the management of these complications and patient outcomes is not well described, the objective of this case series is to describe the open and endovascular management of degenerative CSVs at a tertiary community center. METHODS: All CSVs implanted for lower extremity bypass at our institution between 2001 and 2021 were retrospectively reviewed. All CSVs with evidence of aneurysmal change were included in this study. CSVs with evidence of active infection were excluded. The decision to intervene was left to the discretion of the operating surgeon. Demographic data, indications for the index operation, and details about subsequent interventions for degenerative CSVs were recorded. Study end points included limb salvage and continued patency. Demographic data, indications for the index operation, and details about subsequent interventions for degenerative CSVs were recorded. RESULTS: Seventeen bypasses were identified to have aneurysmal degeneration in 13 patients in the absence of infection between 2001 and 2021. Nine of the 13 patients were male, and the average age and body mass index during the index procedure were 72 and 28, respectively. Indications for the index bypass included acute limb ischemia (9), popliteal aneurysm (2), and chronic limb threatening ischemia with Rutherford's class IV (5) and V (1). The mean time between the index procedure and first graft revision due to aneurysmal changes was 4 years. Most of the aneurysms did not occur at the site of anastomosis with 13 occurring in the body of the graft. Thirteen grafts were managed with open surgery and 3 were managed with endovascular techniques. All endovascular repairs were managed via covered stenting. Patients were followed for an average duration of 7 years from the initial bypass and 2 years from their last aneurysmal repair. Limb salvage in this cohort was 87% with 2 limbs requiring amputation, all of whom underwent open reconstruction. The mortality rate in this series was 54% and no patients died due to complications from their graft. Continued patency on Kaplan Meier survival curve analysis was 79% at 6 months, 65% at 1 year, 54% at 3 years, and 27% at 5 years. CONCLUSIONS: In our experience, aneurysmal degeneration of CSV grafts was mostly managed with standard open surgical techniques, although endovascular therapy also proved acceptable. Limb salvage rates and continued patency of repair at 1 year in this cohort were acceptable. This case series highlights the importance of diligent surveillance for patients with CSVs.

Disparities in Access to Robotic Knee Arthroplasty: A Geospatial Analysis.

BACKGROUND: The utilization of robotic knee arthroplasty (RKA) continues to increase across the United States. The aim of this geospatial analysis was to elucidate if RKA is distributed uniformly across the United States or if disparities exist in patient access. METHODS: Publicly available provider-finding functions for 5 major manufacturers of RKA systems were used to obtain the practice locations of surgeons performing RKA along with their associated RKA system manufacturer. The average travel distance for each county to the nearest RKA surgeon was calculated and Moran's index clustering analysis was used to find hotspots and coldspots of RKA access. A logistic regression model was used to identify the predictive odds ratios between robotic hotspots and coldspots with county-level sociodemographic variables. Of the 34,216 currently practicing orthopedic surgeons in 2022, 2,571 have access to robotic assistance for knee arthroplasty. RESULTS: Hotspots of increased travel time were predominantly in West South Central and West North Central census regions. Hotspots were significantly more rural and consisted of predominantly White populations, with lower median income and health insurance coverage. CONCLUSIONS: The results of the current study align with existing literature, demonstrating absolute geographic access disparities for rural and economically disadvantaged populations. Additionally, relative access disparities persist for minority populations and individuals with high comorbidity burdens residing in urban areas.

1.5 T magnetic resonance imaging generates accurate 3D proximal femoral models: Surgical planning implications for femoroacetabular impingement.

The objective of this study was to validate three-dimensional (3D) proximal femoral surface models generated from a 1.5 T magnetic resonance imaging (MRI) by comparing these 3D models to those derived from the clinical "gold standard" of computed tomography (CT) scan and to ground-truth surface models obtained by laser scans (LSs) of the excised femurs. Four intact bilateral cadaveric pelvis specimens underwent CT and MRI scans and 3D surface models were generated. Six femurs were extracted from these specimens, and the overlying soft tissues were removed. The extracted femurs were then laser scanned to produce a ground-truth surface model. A 3D-3D registration method was used to compare the signed and absolute surface-to-surface distances between the 3D models. Absolute agreement was evaluated using a 95% confidence interval (CI) derived from the precision of the LS ground-truth. Paired samples t tests and Kolmogrov-Smirnov tests were performed to compare the differences between the signed and absolute surface-to-surface distances between the models. The average signed surface-to-surface distances for the MRI vs LS and MRI vs CT models were 0.07 and 0.16 mm, respectively. These differences fell within the 95% CI of ±0.20 mm indicating absolute agreement between the surface models generated from these modalities. The signed surface-to-surface distance was significantly smaller for MRI vs LS ground truth model as compared with the CT vs LS model. Femoral models derived from a 1.5 T MRI scan demonstrated absolute agreement with the clinical gold standard of CT-derived models and were most like LS ground truth models of the excised femurs.