Revision Total Knee Arthroplasty for Ballistic Component Damage From an Intra-articular Missile.

Gunshot wounds (GSWs) and total knee arthroplasty (TKA) are increasingly common, yet a GSW to a TKA is a rare injury. A 60-year-old man sustained an intra-articular GSW to a prior TKA. The patient was scheduled for irrigation and debridement with polyethylene liner exchange. Intraoperatively, the new polyethylene liner was unable to engage the tibial tray. Damage to the locking mechanism on the tibial tray was suspected so total revision proceeded. Upon inspection of the explanted components, it was noted that a bullet fragment offline from the missile trajectory had blocked the locking of the polyethylene liner in the tibial tray. Expeditious antibiotics should be given and meticulous debridement should be performed to avoid unnecessary total component revision.

Increased Complications in Octogenarians Undergoing Same-Day Discharge following Total Knee Arthroplasty: A Matched Cohort Analysis.

Same-day discharge pathways in total knee arthroplasty (TKA) are gaining popularity as a means to increase patient satisfaction and reduce overall costs, but these pathways have not been thoroughly evaluated in potentially at-risk populations, such as in patients ≥80 years old. The purpose of this study was to compare 90-day complications and mortality following same-day discharge after primary TKA in patients ≥80 years old and those <80 years old. Patients who underwent unilateral primary TKA, were discharged on postoperative day 0, and had a minimum 90-day follow-up were identified in a national insurance claims database (PearlDiver Technologies) using Current Procedural Terminology code 27447. These patients were stratified into two cohorts based upon age: (1) nonoctogenarians (<80 years old) and (2) octogenarians (≥80 years old). These cohorts were propensity matched based upon sex, Charlson comorbidity index, and obesity status. Univariate analysis was performed to determine differences in 90-day complications and mortality between the two cohorts. In total, 1,111 patients were included in each cohort. Both cohorts were successfully matched, with no observed differences in matched parameters for demographics or comorbidities. There was no significant difference in 90-day mortality between the two cohorts (p = 0.896). However, octogenarians were at significantly increased risk of postoperative atrial fibrillation (20.8 vs. 10.4%; p < 0.001), nonatrial fibrillation arrhythmias (8.4 vs. 5.6%; p = 0.009), pneumonia (4.5 vs. 2.2%; p = 0.002), stroke (3.1 vs. 1.7%; p = 0.037), heart failure (10.5 vs. 7.5%; p = 0.012), and urinary tract infection (UTI; 14.3 vs. 9.4%; p < 0.001) compared with the nonoctogenarian cohort. Relative to matched controls, octogenarians were at significantly increased risk of numerous 90-day medical complications following same-day primary TKA, including cardiopulmonary complications, stroke, and UTI. Clinicians should be cognizant of these complications and counsel patients appropriately when electing to perform same-day TKA in the octogenarian population.

Linked kinematic knee balancing in unicompartmental knee arthroplasty.

The traditional approach of restoring a neutral mechanical axis to the lower extremity during total knee arthroplasty (TKA) and unicompartmental knee arthroplasty (UKA) has long been favored due its consistency and reproducibility. The kinematic alignment approach, which accounts for the patient's natural knee alignment and is commonly a few degrees varus to the mechanical axis, has gained popularity in recent years as a technique which reestablishes a more anatomic alignment. Linked Anatomic Kinematic Arthroplasty (LAKA), an extension of the kinematic approach that employs computer-assisted surgical (CAS) navigation, can improve the accuracy and precision of kinematic measurements in unicompartmental knee arthroplasties. This article will describe the LAKA technique in UKA and review early clinical outcomes associated with this technique.

Variations in the Organisms Causing Deep Surgical Site Infections in Fracture Patients at a Level I Trauma Center (2006-2015).

OBJECTIVES: To quantify the current bacteriology of deep surgical site infections (SSIs) after fracture surgery at 1 institution and to compare those data with historical controls at the same institution, assessing variations in infecting organisms over the past decade. DESIGN: Retrospective review. SETTING: Level I trauma center. PATIENTS/PARTICIPANTS: Two hundred forty-three patients requiring surgical intervention for deep SSI between January 2011 and December 2015 were compared with 211 patients requiring surgical intervention for deep SSI between December 2006 and December 2010. INTERVENTION: None. MAIN OUTCOME MEASUREMENTS: Bacteria were categorized as Staphylococcus aureus, coagulase-negative staphylococci (CoNS), Streptococcus, Enterococcus, gram-negative rods (GNR), gram-positive rods, anaerobes, or negative cultures. The proportion of each bacterial type was determined and compared with previously published data from the same trauma center (December 2006 to December 2010). RESULTS: Patients most commonly had S. aureus infections (48%), followed by GNR (40%) and CoNS (19%). The proportion of CoNS species (26% vs. 12%, P < 0.01) in infected patients was significantly higher during the current study period compared with historical controls. The proportion of S. aureus species in infected patients was significantly less during the current study period (39% vs. 56%, P < 0.01). The reduction in the proportion of S. aureus species in infected patients was driven by a decrease in the proportion of methicillin-resistant S. aureus (MRSA) in the overall sample. CONCLUSIONS: Bacteriology of deep SSI of fractures has changed substantially over the past decade at our center, specifically the proportions of GNR, CoNS, and MRSA. LEVEL OF EVIDENCE: Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Do Orthopaedic Resident and Fellow Case Logs Accurately Reflect Surgical Case Volume?

OBJECTIVE: The purpose of this study is to determine whether orthopedic resident and fellow case logs accurately reflect trainee case volume. DESIGN: For each orthopedic case performed at our institution between 7/1/14 and 10/31/14, the names of trainees who participated were obtained from the chart. The trainee Accreditation Council for Graduate Medical Education case logs were queried to determine if the procedure in question was logged and, if so, which current procedural terminology (CPT) codes were reported. The CPT codes reported by the trainees were compared to those reported by the attendings in the billing database. To ascertain the opinions of trainees regarding coding, a survey was conducted. SETTING: University of Maryland Medical Center (Baltimore, MD), a tertiary and quaternary care center which features a state-wide trauma referral center as well as orthopedic residency and fellowship training programs. PARTICIPANTS: All orthopedic surgery residents and fellows present at the institution during the study period. RESULTS: Trainees failed to log their cases 24% of the time (465/1925), including 25% (283/1117) for residents and 23% (182/808) for fellows (p = 0.16). Among cases that were logged, CPT codes were missed 46% of the time (673/1460) and extra codes were added 28% of the time (412/1460) compared to the attendings. In the survey, most trainees stated that it was "extremely" or "very" important for them to be able to code correctly (83%; 29/35). CONCLUSIONS: In this study of orthopedic trainee case logging practices, cases were not logged 24% of the time. Caution should be taken with activities which rely on trainee case logs given the potential for inaccuracy.

Inherent differences in keratinocyte function in hidradenitis suppurativa: Evidence for the role of IL-22 in disease pathogenesis.

Hidradenitis suppurativa (HS) is a chronic, recurrent, inflammatory disease of apocrine gland-bearing skin which affects approximately 1-4% of the population. Defective keratinocyte function has been postulated to play a role in HS pathogenesis. Using an in vitro scratch assay, differences between normal, HS, and chronic wound (CW) keratinocytes were evaluated. Normal keratinocytes exhibited faster scratch closure than HS or CW, with normal samples showing 93.8% closure at 96 hours compared to 80.8% in HS (p = 0.016) and 71.5% in CW (p = 0.0012). The keratinocyte viability was similar in normal and HS (91.12 ± 6.03% and 86.55 ± 3.28%, respectively, p = 0.1583), but reduced in CW (72.34 ± 13.12%, p = 0.0138). Furthermore, apoptosis measured by annexin V/propidium iodide, was higher in CW keratinocytes (32.10 ± 7.29% double negative cells compared to 68.67 ± 10.37% in normal and 55.10 ± 9.46% in HS, p = 0.0075). Normal keratinocytes exhibited a significantly higher level of IL-1α (352.83 ± 42.79 pg/ml) compared to HS (169.96 ± 61.62 pg/ml) and CW (128.23 ± 96.61 pg/ml, p = 0.004). HS keratinocytes exhibited significantly lower amounts of IL-22 (8.01 pg/ml) compared to normal (30.24 ± 10.09 pg/ml) and CW (22.20 ± 4.33 pg/ml, p = 0.0008), suggesting that defects in IL-22 signaling may play a role in HS pathogenesis. These findings support intrinsic differences in keratinocyte function in HS which cannot be attributed to reduced keratinocyte viability or increased apoptosis.

Post-discharge adherence with venous thromboembolism prophylaxis after orthopedic trauma: Results from a randomized controlled trial of aspirin versus low molecular weight heparin.

BACKGROUND: Orthopedic trauma patients are often treated with venous thromboembolism (VTE) chemoprophylaxis with aspirin or low molecular weight heparin (LMWH) after discharge from their index admission, but adherence patterns are not known. We hypothesized that overall adherence would be moderate and greater with aspirin compared to LMWH. METHODS: We conducted a randomized controlled trial of adult trauma patients with an operative extremity fracture or any pelvic/acetabular fracture requiring VTE prophylaxis. Patients were randomized to receive either LMWH 30 mg BID or aspirin 81 mg BID. Patients prescribed outpatient prophylaxis were contacted between 10 and 21 days after discharge to assess adherence measured by the validated Morisky Medication Adherence Scale (MMAS-8). Adherence scores were compared between the two treatment arms with similar results for intention-to-treat and as-treated analyses. As-treated multivariable logistic regression was performed to determine factors associated with low-medium adherence scores. RESULTS: One hundred fifty patients (64 on LMWH, 86 on aspirin) on chemoprophylaxis at time of follow-up completed the questionnaire. As-treated analysis showed that adherence was high overall (mean MMAS 7.2 out of 8, SD 1.5) and similar for the two regimens (LMWH: 7.4 vs. aspirin: 7.0, p = 0.13). However, patients on LMWH were more likely to feel hassled by their regimen (23% vs. 9%, p = 0.02). In a multivariable model, low-medium adherence was associated with taking LMWH as the prophylaxis medication (aOR 2.34, CI 1.06-5.18, p = 0.04), having to self-administer the prophylaxis (aOR 4.44, CI 1.45-13.61, p < 0.01), being of male sex (aOR 2.46, CI 1.10-5.49, p = 0.03), and of younger age (aOR 0.72 per additional 10 years of age, CI 0.57-0.91, p < 0.01). CONCLUSIONS: Overall post-discharge adherence with VTE prophylaxis was high. Several factors, including prophylaxis by LMWH, were associated with decreased adherence. These factors should be considered when managing patients and designing efficacy trials. LEVEL OF EVIDENCE: Therapeutic, level II.