Varus-valgus constrained (VVC) devices are typically used in revision settings, often with stems to mitigate the risk of aseptic loosening. However, in at least one system, the VVC insert is compatible with the primary posterior-stabilized (PS) femoral component, which may be an option in complex primary situations. We sought to determine the implant survivorship, radiological and clinical outcomes, and complications when this VVC insert was coupled with a PS femur without stems in complex primary total knee arthroplasties (TKAs). Through our institution’s total joint registry, we identified 113 primary TKAs (103 patients) performed between 2007 and 2017 in which a VVC insert was coupled with a standard cemented PS femur without stems. Mean age was 68 years (SD 10), mean BMI was 32 kg/m2 (SD 7), and 59 patients (50%) were male. Mean follow-up was four years (2 to 10).Aims
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Septic arthritis of the native knee often results in irreversible joint damage leading to the need for a total knee arthroplasty (TKA). This study examines the mid-term risk of periprosthetic joint infection (PJI), aseptic revision, any revision, and any reoperation in primary TKAs after septic arthritis of the native knee compared to a control cohort of primary TKAs performed for osteoarthritis (OA). We retrospectively identified 215 primary TKAs performed between 1971 and 2016 at a single institution following septic arthritis of the native knee. Eighty-two percent (177 cases) were treated in a single setting, whereas a two-stage exchange arthroplasty protocol was utilized in 18% (39 cases) for ongoing or suspected active native knee septic arthritis. Each case was matched 1:1 based on age, sex, body mass index (BMI), and surgical year to a primary TKA for OA. Mean age and BMI were 63 years and 30 kg/m2, respectively. Mean follow-up was 9 years.Introduction
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Revision total knee arthroplasty (revision TKA) occurs for a wide variety of indications and along with revision total hip arthroplasty is billed for using Diagnosis-Related Groups (DRGs) 466, 467, and 468 in the United States. However, DRGs do not account for revision etiology, a potentially substantial driver of cost. This study investigates revision TKA costs and 30-day complications by indication, employing both local granular as well as national standardized databases. Hospitalization costs and complication rates for 1,422 aseptic revision TKAs performed at a high-volume center between 2009 and 2015 were retrospectively reviewed. Additionally, charges for 28,173 revision TKAs in the National Inpatient Sample (NIS) were converted to costs using the Healthcare Cost and Utilization Project cost-to-charge ratios. 30-day complication rates for 3,450 revision TKAs were obtained using the American College of Surgeons National Surgical Quality Improvement Project (ACS-NSQIP). Costs and complications were compared between revision TKAs performed for the indication of fracture, wear/loosening, and instability with use of simultaneous and pairwise comparisons and a multivariable model accounting for American Society of Anesthesiologists (ASA) score, age, and sex.Introduction
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In the setting of periprosthetic joint infection, the complete removal of implants and cement can be challenging with well-fixed, cemented implants about the knee. This can get especially complex in the setting of long cemented femoral stems. Osteotomies are well described in the proximal femur and tibia for removal of implants and cement. There is little information available on distal femoral osteotomies to facilitate knee implant and retained cement removal. We describe a novel anterolateral oblique distal femoral osteotomy for the removal of well-fixed, cemented components during resection knee arthroplasty that preserves vascularity to the osteotomized segment. Cadaveric anatomic vascular injection studies were performed to document vascularity of the osteotomized segment. Clinical examples, and results will be presented.Introduction
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First generation cephalosporins remain the gold standard perioperative antibiotic for total hip and knee arthroplasty (THA, TKA). However, some patients have documented or self-reported allergies to antibiotics, most commonly penicillin, that result in changes to perioperative antibiotic coverage. Furthermore, patients testing positive for methicillin resistant staphylococcus aureus (MRSA) represent another group where an alternative to cefazolin, typically vancomycin, is often chosen for perioperative prophylaxis. The aims of this study were to 1) characterize the antibiotic choices for perioperative prophylaxis at the time of primary TKA and THA, 2) assess the efficacy of a preoperative antibiotic allergy testing program, and 3) determine rates of periprosthetic joint infection (PJI) based on perioperative antibiotic regimen. We evaluated all patients undergoing primary TKA or THA at a single academic institution from January 2004-May 2017, yielding a cohort of 29,695 patients. A series of institutional databases were combined to determine which patients underwent antibiotic allergy testing prior to surgery, outcomes from the allergy consultation, perioperative antibiotic management strategy, and survivorship free of infection until final follow-up.Introduction
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In the lower extremity, lymphedema is characterized by fluid buildup and swelling which can lead to fibrosis of the skin and recurring soft-tissue infections. Risk factors include obesity, older age, lower extremity surgery, and radiotherapy. There is currently a paucity of data examining the impact of lymphedema in primary total knee arthroplasty (TKA). The purpose of this study was to review outcomes following primary TKA performed in patients with lymphedema compared to a matched cohort with primary osteoarthritis. Over a 19-year period (1998–2016), 144 patients underwent primary TKA with a preceding diagnosis of ipsilateral lymphedema (Table 1). There were 114 (79%) females, a mean age of 69 years, and mean BMI of 37.1 kg/m2. Mean follow-up was 7-years (range 2–17 years). A blinded analyst completed a 1:2 match of patients with lymphedema to a group of patients without lymphedema undergoing primary TKA for osteoarthritis during the same period. Matching criteria included sex, age, date of surgery, and BMI. Matched controls included 228 (79%) females along with a mean age and BMI of 69 and 36.4 kg/m2. The mean follow-up for the comparison cohort was 8 years (range 2–18 years). There were no significant differences between groups on the evaluated baseline parameters. Results: Patients with a history of lymphedema were at a significantly increased risk of revision TKA (HR 7.60, P<0.001), reoperation for any cause (HR 2.87, P<0.001), and postoperative infection (HR 6.19, P<0.001). Patients with lymphedema were also at increased risk for periprosthetic fracture (p=0.04) and tibial component loosening (p=0.01). Morbid obesity increased the risk of reoperation (HR 2.11, p=0.02) and trended toward increased risk of revision TKA (HR 2.29, p=0.059) and infection (HR 2.37, p=0.06). Discussion: Patients with lymphedema are at significantly increased risk of revision, reoperation, and infection following primary TKA. This data highlights the need for appropriate patient counseling in this population and optimization of lymphedema management before and after TKA.Introduction
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Bilateral total knee arthroplasty (TKA) can be performed under a single-anesthetic (SA) or staged under a two-anesthetic (TA) technique. Recently, our institution began piloting a two-surgeon team SA method for bilateral TKA. The purpose of this study was to compare the inpatient costs and clinical outcomes in the first 90 days after surgery between the team SA, single-surgeon SA, and single-surgeon TA approaches for bilateral TKA. All primary TKA performed from 2007–2017 by the two participating surgeons for each of the 3 groups of interest were identified: team SA (N=42 patients; 84 knees), single-surgeon SA (N=146 patients; 292 knees), single-surgeon TA (N=242 patients; 484 knees). No patients were lost to follow-up.Introduction
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