If, When, and How to Use Rifampin in Acute Staphylococcal Periprosthetic Joint Infections, a Multicentre Observational Study.

BACKGROUND: Rifampin is generally advised in the treatment of acute staphylococcal periprosthetic joint infections (PJI). However, if, when, and how to use rifampin remains a matter of debate. We evaluated the outcome of patients treated with and without rifampin, and analyzed the influence of timing, dose and co-antibiotic. METHODS: Acute staphylococcal PJIs treated with surgical debridement between 1999 and 2017, and a minimal follow-up of 1 year were evaluated. Treatment failure was defined as the need for any further surgical procedure related to infection, PJI-related death or the need for suppressive antimicrobial treatment. RESULTS: A total of 669 patients were analyzed. Treatment failure was 32.2% (131/407) in patients treated with rifampin and 54.2% (142/262) in whom rifampin was withheld (P < .001). The most prominent effect of rifampin was observed in knees (treatment failure 28.6% versus 63.9%, respectively, P < .001). The use of rifampin was an independent predictor of treatment success in the multi-variate analysis (OR 0.30, 95% CI 0.20 - 0.45). In the rifampin group, the use of a co-antibiotic other than a fluoroquinolone or clindamycin (OR 10.1, 95% CI 5.65 - 18.2) and the start of rifampin within 5 days after surgical debridement (OR 1.96, 95% CI 1.08 - 3.65) were predictors of treatment failure. The dosing of rifampin had no effect on outcome. CONCLUSIONS: Our data supports the use of rifampin in acute staphylococcal PJIs treated with surgical debridement, particularly in knees. Immediate start of rifampin after surgical debridement should probably be discouraged, but requires further investigation.

Overstuffing in total knee replacement: no effect on clinical outcomes or anterior knee pain.

PURPOSE: With total knee replacement (TKR), correct sizing and rotational alignment are essential for good clinical outcomes. Overstuffing may result in loss of flexion and adversely affect the outcome of TKR. The purpose of this study was to correlate overstuffing with patient reported clinical outcomes and anterior knee pain (AKP). METHODS: Baseline and follow-up clinical and radiological data of 262 patients who had NexGen LPS posterior stabilized TKR without patellar resurfacing between 2008 and 2009 were prospectively collected. We measured anterior femoral offset, femoral diameter, and posterior condylar offset on the pre-operative and postoperative lateral non-weight bearing radiographs. Overstuffing was defined as an increase in pre-operative to postoperative values. Repeated measures analysis of variance (ANOVA) was used to analyse for differences from preoperative to postoperative WOMAC scores between patients with and without overstuffing. RESULTS: A total of 193 sets of lateral radiographs (preoperative and postoperative) were adequate for analysis. Anterior overstuffing was noted in 84 patients (43.5%), posterior overstuffing in 168 (87%), and total overstuffing in 155 patients (80%). Total WOMAC scores were similar in patients with and without anterior, posterior or total overstuffing (p = 0.11, p = 0.65, and p = 0.06, respectively). We found no relation between the presence of AKP with either anterior, posterior or total overstuffing (chi-square: p = 0.14, p = 0.24, and p = 0.54, respectively). CONCLUSIONS: We found no relation between radiological anteroposterior overstuffing with patient reported outcome measures or AKP.

Two-Step 3D-Guided Supramalleolar Osteotomy to Treat Varus Ankle osteoarthritis.

BACKGROUND: Success of valgus-type supramalleolar osteotomy (SMOT) depends on adequate correction of malalignment, which can be hard to achieve with current 2-dimensional (2D) planning and operative techniques. A personalized digital 3-dimensional (3D) workflow to virtually plan and perform a 2-step 3D-guided medial opening (MO) SMOT has the potential to improve precision of correction. METHODS: Computed tomography (CT)-based Proplan medical 3D models were made to virtually plan the desired MO SMOT, and exported to 3-Matic medical to develop patient-specific 2-step cutting and wedge guides. Workflow accuracy was tested in this limited clinical pilot study (3 patients) by comparing the virtual planned position of the osteotomized distal tibial fragment with the 1-year post-MO SMOT configuration. Two millimeters or less translation deviation in every plane was defined as accurate. RESULTS: Primary outcome analysis of the osteotomized distal tibial fragment deviation showed a median translation in all planes of 0.7 (range 0-8.2) mm (interquartile range 1.55) with an excellent interrater reliability of the measurements (intraclass correlation coefficient 0.998). There was a strong reduction in ankle pain as reflected by an increase of the AOFAS-AH score and decrease of NRS pain score with an unrestricted hindfoot motion 1 year after surgery. CONCLUSION: 3D virtually planned bone cutting and wedge guides is a promising approach associated with minimal postoperative deviation from the desired correction in medial opening supramalleolar osteotomy.