A Review of the Literature on Culture-Negative Periprosthetic Joint Infection: Epidemiology, Diagnosis and Treatment

PURPOSE: The prevalence of periprosthetic joint infection (PJI) has increased with the increasing incidence of arthroplasty surgery. Considering identification of causative microorganisms is crucial for treatment of PJI, culture-negative (CN) PJI is a significant clinical issue. The purpose of the present study is to describe epidemiology, diagnosis and treatment of CN PJI based on review of the literature to help prevent delayed diagnosis and improve clinical outcomes of CN PJI. METHODS: MEDLINE, EMBASE, Cochrane Library and Scopus databases were searched for articles on CN PJI. Only clinical studies written in English were included. Basic science studies, letters to the editor, case reports and review articles on PJI were excluded. RESULTS: Seven studies were included in this study. The prevalence of CN PJI ranged from 0% to 42.1%. The major risk factors for CN PJI were prior antibiotic use and presence of postoperative wound drainage. Vancomycin and cephalosporins were the most commonly used antibiotics for CN PJI. Two-stage revision arthroplasty followed by 6 weeks of antibiotic therapy produced the most successful treatment outcomes. CONCLUSIONS: In most clinical studies on CN PJI, a definite diagnostic method for identifying causative microorganisms or optimal treatment strategy for CN PJI were not clearly described. Therefore, further studies are needed to establish standard diagnostic methods for identifying infecting organisms and treatment strategies for CN PJI.

Two-Stage Total Knee Arthroplasty for Prosthetic Joint Infection

PURPOSE: This retrospective review was conducted to identify prognostic factors for two-stage reimplantation for infected total knee arthroplasty (TKA) and the rate of reinfection following revision TKA. MATERIALS AND METHODS: Out of 88 patients diagnosed with post-TKA infection between 1998 and 2011, 76 underwent two-stage reimplantation and were reviewed in this study. The 76 patients were divided into two groups-those who experienced reinfection and those who did not. Comorbidities, culture results, and inflammation indices were analyzed and compared between the two groups. RESULTS: Of the 76 patients who underwent a two-stage reimplantation, 18 (23.7%) experienced reinfection. Patients with more than three comorbidities had significantly higher reinfection rates than those with less than three comorbidities (47.1% vs. 4.8%, p=0.032). The reinfection rate between the culture positive prosthetic joint infection group and the culture negative prosthetic joint infection group was not significantly different (p=0.056). Inflammation indices (erythrocyte sedimentation rate [ESR] and C-reactive protein [CRP]) showed a statistically significant difference between patients with reinfection and those without reinfection at 4 weeks after the first-stage surgery. CONCLUSIONS: Reimplantation must be carefully performed when the risk of reinfection is high, particularly in patients with more than three systemic or local comorbidities and higher inflammation indices (ESR and CRP) prior to revision TKA.

Correlation between Femoral Guidewire Position and Tunnel Communication in Double Bundle Anterior Cruciate Ligament Reconstruction

PURPOSE: The object of this study was to determine the shortest possible distances of antero-medial (AM) and postero-lateral (PL) guide wire tunnel positions required to prevent femoral bone tunnel communication in double-bundle anterior cruciate ligament (ACL) reconstruction using human cadaver knees. MATERIALS AND METHODS: The centers of femoral AM and PL bundles of 16 cadaveric knees were drilled with guide wires and the distances of guide wires, were measured upon entrance into the bone. Femoral tunnel drilling was performed using transportal technique. The diameters of AM and PL graft were 8 mm and 6 mm, respectively. CT scans were taken on each knee, and 3-dimensional models were constructed to identify the femoral tunnel position and to create AM and PL tunnel virtual cylinders. Thickness of the bone bridge between the two tunnels was measured. RESULTS: In four out of six specimens, in which the guide wires were placed at less than or equal to 9 mm, communication was noted. In specimens with guide wires placed at distances greater than or equal to 10 mm, communication was not noted. The two groups showed a statistically significant difference (p=0.008). In cases where the distance between the AM and PL femoral tunnel guide wires was 12 mm, the bone bridge thickness was greater than 2 mm along the tunnel. CONCLUSION: The technique for double bundle-anterior cruciate ligament (DB-ACL) reconstruction that we show here can avoid bone tunnel communication when AM and PL femoral guide wires are placed at least 10 mm apart, and 12 mm should be kept to preserve 2 mm bone bridge thickness.

Radiographic Analysis of Tibial-Articular Surface Angle According to the Selection of the Mechanical Axis / 대한족부족관절학회지

PURPOSE: We investigated a statistical difference of tibial-articular surface (TAS) angles between radiographs of standing ankle anteroposterior (AP) and whole lower extremity view, and evaluated whether the tibial axis obtained from the standing ankle AP view reflects the original mechanical axis of lower extremity. MATERIALS AND METHODS: Both the standing ankle AP and whole lower extremity view were taken from 60 legs of 30 healthy volunteers without a history of ankle surgery or deformity of lower limb. To determine the tibial axis, Takakura's and Hintermann's method were employed in the standing ankle AP view. To compare these results with the original TAS angle, ANOVA and multiple comparison test were used. RESULTS: The mean TAS angle was 88.3 degrees(from hip joint to ankle), 89.5 degrees (from knee joint to ankle), 88.5 degrees (Takakura's method), and 90.2 degrees(Hintermann's method). Although there was a statistical significance (p=0.000) between these results, Takakura's method had no significant difference, compared to the results of whole extremity view by the multiple comparison test. CONCLUSION: The tibial axis obtained by Takakura's method reflects the original mechanical axis of lower extremity. When a surgical procedure is planned, however, it is necessary to consider that the ankle radiographs do not provide any information on the proximal deformity without the whole lower extremity view.