New Primary Total Knee Arthroplasty Components Versus Other Contemporary Types of Spacers for the Treatment of Chronic Periprosthetic Knee Infection With a Two-Stage Protocol.

The optimal type of antibiotic spacer for the treatment of a knee periprosthetic joint infection (PJI) remains a topic of debate. Although the ultimate goal of an antibiotic spacer is infection control, contemporary spacer iterations, such as the use of a new femoral component (NFC), may offer unique advantages. The primary goal of this study was to compare rates of infection control and functional outcomes between contemporary spacer types. We retrospectively reviewed 96 patients who underwent removal of a total knee arthroplasty with insertion of an antibiotic spacer for knee PJI over a 14-year period at a single institution with a minimum 1-year follow-up. Three patient cohorts were defined based on spacer type: NFC (n=30), cement-on-cement (n=19), and static (n=47). There was no association between spacer type and the odds of infection clearance (P=.60). The NFC spacers resulted in increased knee range of motion before replantation and improved ambulatory status at 8 weeks postre-plantation, although no difference was seen at final follow-up. The use of NFC spacers may provide functional advantages over their contemporary counterparts, and the potential of NFC spacers to be used in single-stage exchange arthroplasty remains an appealing area of investigation. Future high-powered, prospective, noninferiority studies between contemporary spacer types are needed. [Orthopedics. 2022;45(2):109-115.].

Nonoperative Management of Subclavian Artery Thrombosis in Pediatric Clavicle Fractures: A Case Report.

CASE: A 12-year-old patient presented after a fall onto her upper extremity. She was found to have a mildly displaced clavicle fracture with a subclavian artery thrombosis. Given the reconstitution of flow distal to the thrombosis, the patient was treated nonoperatively in consultation with vascular surgery with anticoagulation and a sling for immobilization. CONCLUSION: This case highlights the importance of a thorough neurovascular examination even in a mildly displaced fracture. Nonoperatively managed thromboses may be treated successfully without orthopaedic fixation or vascular intervention, although the natural history of this injury is likely not fully understood.

Management of Periprosthetic Hip and Knee Joint Infections With a Known Sinus Tract-A Single-Center Experience.

BACKGROUND: Prosthetic joint infection (PJI) is a serious complication after total joint arthroplasty (TJA). A sinus tract communicating with a prosthetic joint is a major criterion defining PJI. Despite this fact, many patients presenting with a draining sinus tract undergo invasive procedures before initiation of two-stage revision arthroplasty. We hypothesized that many patients undergo nondefinitive procedures to treat the sinus tract, rather than undergoing definitive treatment of infection with two-stage revision. METHODS: A retrospective review of all cases of two-stage revision arthroplasty at Loyola University Medical Center between January 2004 and May 2018 was performed. Patients with infected TJA and periprosthetic sinus tract were included. Records were queried for laboratory values and prior procedures. RESULTS: We identified 160 patients who underwent two-stage revision for infection over the 14-year period. Of the 160 patients, 25 had a documented periprosthetic sinus tract before initiation of definitive revision arthroplasty and were included. Eleven (44.0%) had one or more procedures including interventional radiology drain placement, local wound care, or formal irrigation and debridement before definitive treatment. Forty-five percent of patients that underwent nondefinitive procedures before definitive surgery had either an erythrocyte sedimentation rate or C-reactive protein at normal or near-normal levels. CONCLUSION: Many arthroplasty patients presenting with periprosthetic sinus tracts undergo nondefinitive procedures before definitive treatment. Inherent surgical risks of these procedures can increase the overall morbidity and mortality of these patients. Further effort is needed to educate surgeons regarding management of sinus tracts after TJA.

Evaluation for septic arthritis of the native adult knee is aided by multivariable assessment.

INTRODUCTION: Evaluation of suspected septic arthritis of the native adult knee is a common diagnostic dilemma. Pre-aspirate criteria predictive of septic arthritis do not exist for the adult knee and investigations of aspiration results (cell count, differential, gram stain and crystal analysis) have been limited to univariate analyses. Given numerous clinical variables inform the risk of septic arthritis, multivariable analysis that incorporates all clinically available information is critical to allowing accurate decision-making. METHODS: We retrospectively identified 455 cases of potential septic arthritis of a native adult knee at a tertiary health system from 2012 to 2017, of which 281 underwent aspiration. We recorded demographics, comorbidities, history, exam, laboratory, and radiographic data. Among aspirated cases, we performed univariate analyses of all variables for association with septic arthritis followed by multivariable logistic regression analysis. RESULTS: Septic arthritis was confirmed in 61 of 281 patients who underwent aspiration. Independent associations of risk for septic arthritis included synovial fluid WBC ≥ 30,000 (Odds Ratio 90.8, 95% Confidence Interval 26.6-310.1, p < 0.001), bacteria reported on synovial fluid gram stain (OR 21.5, 95% CI 3.9-119.2, p < 0.001), duration of pain >2 days (OR 6.9, 95% CI. 2.3-20.9, p < 0.001), history of septic arthritis at any joint (OR 5.0, 95% CI 1.1-23.4, p = 0.039), clinical effusion (OR 4.8, 95% CI 1.2-20.0, p = 0.030). Independent associations protective against septic arthritis included presence of synovial fluid crystals (OR 0.1, 95% CI 0.1-0.4, p < 0.001). The multivariable model was highly accurate in discriminating between septic and aseptic cases (AUC = 0.942). A web-based tool was created to aid clinical decision-making. CONCLUSION: When evaluating for septic arthritis of a native adult knee, several independent associations were identified for variables related and unrelated to joint aspiration. The associated multivariable model discriminated very well between patients with and without septic arthritis, outperforming previous univariate assessments. A web-based tool was created that estimates the probability of septic arthritis based on this model. This may aid decision-making in complex clinical scenarios.

Characterization of Outcomes of 2-Stage Exchange Arthroplasty in the Treatment of Prosthetic Joint Infections.

BACKGROUND: Two-stage revision is the preferred treatment for prosthetic hip and knee infections in the United States. Recent studies have questioned the true success rate of this treatment. The purpose of this study is to investigate outcomes of prosthetic hip and knee infections undergoing resection arthroplasty and spacer insertion at a single institution. METHODS: We identified 103 patients who underwent prosthesis resection and spacer placement for infection over a 10-year period. Twenty-three cases were excluded based on preset exclusion criteria leaving 80 cases (56 knees, 24 hips). A retrospective review was performed to examine the outcomes of these patients. RESULTS: Following spacer placement but before reimplantation, 9 (11.25%) of the 80 joints underwent repeat debridement and spacer exchange for persistent infection. Twenty-four (30.00%) patients had a serious complication during their treatment course. Fourteen (17.50%) patients never underwent reimplantation. Of these, 10 continued with spacer retention, 2 had resection arthroplasty, and 1 each had an amputation and an arthrodesis. Of the 66 patients with successful reimplantation, 48 (72.70%) remained infection free at most recent follow-up. CONCLUSIONS: Two-stage revision does not result in the high rates of cure reported previously, when taking into account the substantial number of patients who never undergo the subsequent reimplantation surgery. Of those who underwent reimplantation in our study, many required additional spacer exchange or had complications. Surgeons and patients should consider these outcomes when discussing the treatment of prosthetic hip and knee infections.

Wound Hygiene Practices After Total Knee Arthroplasty: Does It Matter?

BACKGROUND: Current literature is limited with regard to standardized postoperative surgical site hygiene after total knee arthroplasty (TKA). With little guidance from the literature, the timing of permissible postoperative cleaning is a decision made by the individual surgeon using anecdotal evidence. A standardized wound care regimen is of particular interest to minimize the risk of infection. METHODS: To examine what species of bacteria recolonize the surgical site postoperatively, a randomized controlled trial was performed of 16 TKA patients who were allowed to shower at 2 days postoperatively and of 16 patients who were asked to wait until 2 weeks postoperatively before showering after TKA. Culture swabs of skin adjacent to the incision were performed preoperatively, just after incision closure, at dressing removal, and at 2 weeks postoperatively. Bacteria were speciated and compared between groups. A swab of the contralateral knee was performed at 2 weeks as a control. A survey of patient's preference regarding early and late showering was also carried out. RESULTS: No difference was found between the groups in rate of colonization or bacterial type, and no patients developed infection. Patients overwhelmingly preferred early showering rather than late (P = .28-.99). CONCLUSION: There is no difference in surgical site bacterial recolonization between early and delayed showering after primary TKA.