Metaphyseal Fixation Using Highly Porous Cones in Revision Total Knee Arthroplasty: Minimum Two Year Follow Up Study

BackgroundHighly porous metaphyseal cones have been introduced to restore metaphyseal integrity for improved cement interdigitation to achieve durable fixation in revision total knee arthroplasty (TKA). The purpose of this study is to review the survivorship, clinical results, and complications of revision TKA using highly porous 3-dimensionally printed titanium metaphyseal cones.MethodsThis is a review of 62 revision TKAs using metaphyseal tibial cones, with 15 cases utilizing both tibial and femoral cones. The mean age of the patients was 66 years (range 32-84) who had a mean follow-up of 27 months (range 24-34). There were 38 women and 24 men, who had a mean body mass index of 33 (range 18.3-62).ResultsRevision-free survival of the cones was 90.2%. If infection was excluded, survivorship was 100%. There were no cases of aseptic loosening. The mean Knee Society Score improved from 51 points preoperatively to 80 points at the time of latest follow-up. The mean Knee Society Functional Score improved from 48 points preoperatively to 68 points. A total of 15 of the 62 patients (24%) required additional surgery: 10 (16%) for infection, 3 (5%) for contracture, 1 for patellar subluxation, and 1 for quadriceps tendon rupture.ConclusionMetaphyseal fixation is important for survivorship in revision TKA which can be challenging due to cancellous and structural bone loss encountered at the time of revision. Prosthetic joint infection continues to be the leading cause of failure in revision TKA. The use of highly porous titanium metaphyseal cones produced from 3-dimensionally printed technology used in this study demonstrated excellent short-term results with no cases of aseptic loosening. Further follow-up is required to determine if these results can be durable over a longer period.     

Odontogenic infection leading to cervical emphysema and fatal mediastinitis

A case of fatal mediastinitis following an odontogenic infection has been presented. The anatomic pathways through fascial planes from the mouth to the mediastinum have been reviewed. The causes of cervical emphysema when the oral cavity is an entry site have been discussed. Usually this process is benign, but the possibility that gas-forming anaerobes could be present in the emphysema and that insidious mediastinitis could concurrently occur is stressed. The presence of Bacteroides asaccharolyticus in the anaerobic cultures from the submandibular and chest abscesses, and the recovery of aerobic organisms, leads to speculation about a synergistic action between these organisms.     

Empyema of the gallbladder: A complication in the natural history of acute cholecystitis

Empyema of the gallbladder was identified in 34 patients. Patients undergoing early operation without attempts at nonoperative treatment had less infectious morbidity and mortality. Delayed operative intervention, extrabiliary abscess, perforation of the gallbladder and common duct exploration are factors that contribute to increased risks in these patients.