Staphylococcus lugdunensis prosthetic joint infection: A multicentric cohort study.

OBJECTIVES: To describe Staphylococcus lugdunensis prosthetic joint infection (PJI) management and outcome. METHODS: Adults with proven S. lugdunensis PJI were included in a multicentric retrospective cohort. Determinants for failure were assessed by logistic regression and treatment failure-free survival curve analysis (Kaplan-Meier). RESULTS: One hundred and eleven patients were included (median age 72.4 [IQR, 62.7-79.4] years), with a knee (n = 71, 64.0%) or hip (n = 39, 35.1%) PJI considered as chronic in 77 (69.4%) cases. Surgical management consisted in debridement, antibiotic with implant retention (DAIR; n = 60, 54.1%), two-stage (n = 28, 25.2%) or one-stage (n = 15, 13.5%) exchange. Total duration of antimicrobial therapy was 13.1 (IQR, 11.8-16.9) weeks. After a median follow-up of 99.9 (IQR, 53.9-178.1) weeks, 22 (19.8%) S. lugdunensis-related treatment failures were observed. Independent determinants for outcome were diabetes (OR, 3.741; p = 0.036), sinus tract (OR, 3.846; p = 0.032), DAIR (OR, 3.749; p = 0.039) and rifampin-based regimen (OR, 0.319; p = 0.043). Twenty-four (40.0%) of the 60 DAIR-treated patients experienced treatment failure, with hip location (OR, 3.273; p = 0.048), delay from prosthesis implantation (OR, 1.012 per month; p = 0.019), pre-surgical CRP level >115 mg/L (OR, 4.800; p = 0.039) and mobile component exchange (OR, 0.302; p = 0.069) constituting additional determinants of outcome. CONCLUSIONS: Staphylococcus lugdunensis PJI are difficult-to-treat infections, with pivotal roles of an optimal surgical management.

Long-term survivorship of a monoblock long cementless stem in revision total hip arthroplasty.

PURPOSE: The purpose of this study was to assess the clinical outcomes, complications, and survival of a long cementless titanium femoral stem in revision total hip arthroplasty (THA) at a minimum five year follow-up. METHODS: Between 2000 and 2010, 114 patients (116 hips), with a mean age of 68 ± 12 years, underwent revision THA using a KAR® stem (DePuy, Leeds, UK). The main reasons for revision were aseptic loosening (82%), periprosthetic joint infections (PJI) (11%), and periprosthetic fractures (6%). Mean follow-up was ten ± three years (range, 5-16). Harris Hip Score (HHS), Oxford Hip Score (OHS), and Postel-Merle d'Aubigné (PMA) score were recorded. Radiographic analysis assessed stem osseointegration and subsidence. Survival was analyzed using the Kaplan-Meier (KM) method and cumulative incidence function (CIF). RESULTS: Post-operative HHS was 83 ± 15 (range, 35-99) and OHS was 37 ± 8 (range, 8-48). PMA score significantly increased from 12 ± 2 (range, 5-18) pre-operatively to 14.6 ± 2 (range, 9-18) post-operatively (p = 0.0004). The radiographic Engh score was 15 ± 8 (range, 7-22). Stem subsidence was observed in two cases (3%). At ten years, five stems had been revised, three for infections and two for periprosthetic fractures. Using the KM method, ten year survival free of stem revision for aseptic loosening was 100%, free of revision for any reason 95%, and free of any re-operation 81%. CONCLUSIONS: The present study reported satisfactory outcomes and survival of a long tapered unlocked cementless femoral stem in revision THA at a minimum follow-up of five years.

Salvage Debridement, Antibiotics and Implant Retention ("DAIR") With Local Injection of a Selected Cocktail of Bacteriophages: Is It an Option for an Elderly Patient With Relapsing Staphylococcus aureus Prosthetic-Joint Infection?

Local injection of a bacteriophages mix during debridement, antibiotics and implant retention ("DAIR") was performed to treat a relapsing Staphylococcus aureus chronic prosthetic joint infection (PJI). This salvage treatment was safe and associated with a clinical success. Scientific evaluation of the potential clinical benefit of bacteriophages as antibiofilm treatment in PJI is now feasible and required.

Fewer complications after UKA than TKA in patients over 85 years of age: A case-control study.

INTRODUCTION: Implanting a knee prosthesis in patients aged over 85 years is not without risk. Unicompartmental knee arthroplasty (UKA) is reputed to show lower morbidity and mortality than total knee arthroplasty (TKA). Elderly patients with isolated unicompartmental osteoarthritis without specific contraindications are thus good candidates for this procedure. The present retrospective case-control study compared complications rates in elderly patients receiving UKA versus TKA. The study hypothesis was that UKA incurs fewer complications, with equivalent functional results. MATERIAL AND METHODS: Five hundred and forty-four UKAs were performed between 1987 and 2015; all patients aged 85 years or over (n=30) were included, and age-matched at a rate of 1 UKA for 3 TKAs in our database of 4,216 TKA procedures. Mean age was 87.5 years (range, 85-92 years). The main endpoint was complications rate; secondary endpoints comprised satisfaction, IKS function and knee scores, and implant survival. RESULTS: Mean follow-up was 32 months (range, 12-118 months) for UKA and 34 months (range, 12-100 months) for TKA. The medical complications rate was significantly lower with UKA (6.7% versus 25.6%; P=0.02), with no early mortality. IKS scores were identical between UKA and TKA groups at last follow-up: knee, 93.8 (95% CI [89.7-98.0]) versus 89.5 (95% CI [85.6-93.4]), P=0.06; function, 63.8 (95% CI [53.1-74.5]) versus 67.0 (95% CI [61.3-72.7]), P=0.62. Satisfaction rates were likewise identical: 96% and 97%, respectively (P=0.77); and implant survivorship was identical (P=0.54). DISCUSSION: Early medical complications were fewer after UKA than TKA in a population aged ≥85 years, with comparable clinical outcome. These results argue in favor of UKA in elderly patients with comorbidities. LEVEL OF EVIDENCE: III, case-control study.

Improved joint-line restitution in unicompartmental knee arthroplasty using a robotic-assisted surgical technique.

PURPOSE: Joint-line restitution is one objective of unicompartmental knee arthroplasty (UKA). However, the joint line is often lowered when resurfacing femoral implants are used. The aim of this study was to compare the joint-line height in UKA performed by robotic-assisted and conventional techniques. METHODS: This retrospective case-control study compared two matched groups of patients receiving a resurfacing UKA between 2013 and 2016 by either a robotic-assisted (n = 40) or conventional (n = 40) technique. Each group comprised 27 women and 13 menm wuth a mean age of 69 and 68 years, respectively. Indications for surgery were osteoarthritis (n = 35) and condylar osteonecrosis (n = 5). Two validated radiologic measurement methods were used to assess joint-line height. RESULTS: Forty UKA (23 medial and 17 lateral) were analysed in each group. Restitution of joint-line height was significantly improved in the robotic-assisted group compared than the control group: +1.4 mm ±2.6 vs +4.7 mm ± 2.4 (p < 0.05) as assessed using method 1, and +1.5 mm ±2.3 vs +4.6 mm ±2.5 (p < 0.05) as assessed using method 2. CONCLUSIONS: Restitution of joint-line height in resurfacing UKA can be improved with robotic-assisted surgery. Improvement in clinical outcome measures must be demonstrated with long-term studies.