Role of joint aspiration before re-implantation in patients with a cement spacer in place.

BACKGROUND: The usefulness of a mandatory joint aspiration before re-implantation in patients with a cement spacer already in place is unclear. AIM: To evaluate the role of culturing synovial fluid obtained by joint aspiration before re-implantation in patients who underwent a two-stage septic revision. METHODS: A retrospective observational study was conducted, including patients that underwent a two-stage septic revision (hip or knee) from 2010 to 2017. After the first stage revision and according to intraoperative culture results, all patients were treated with an antibiotic protocol for 6-8 wk. Following 2 wk without antibiotics, a culture of synovial fluid was obtained. The results of these cultures were recorded and compared with cultures obtained during re-implantation surgery. RESULTS: Forty-one patients (20 hip and 21 knee spacers) were included in the final analysis. In 39 cases, the culture of synovial fluid was negative, while in the remaining 2 cases (knee spacers) no analysis was possible due to dry tap. In 5 of the patients, two or more intraoperative cultures taken during the re-implantation surgery were positive. CONCLUSION: We found no evidence to support mandatory joint aspiration before re-implantation in patients with a cement spacer in place.

Role of bacterial colonisation of vancomycin-gentamicin spacers in two-stage arthroplasty revision surgery: the usefulness of spacer sonication.

PURPOSE: In two-stage replacements for septic loosening, some studies have suggested an association between bacterial colonisation of spacers and a higher number of complications after implantation of the definitive prosthesis. Our study aimed to determine the reoperation rate of patients undergoing two-stage revision surgery according to the culture results of spacer sonication. METHODS: A retrospective observational study was conducted in which hip or knee spacers implanted at our institution with a diagnosis of periprosthetic joint infection from 2010 to 2018 were analysed. Patients were grouped into three categories: A. Patients with positive spacer sonication fluid culture, with or without positive cultures of the rest of the samples. B. Patients with negative spacer sonication culture and negative cultures of the rest of intraoperative samples. C. Patients with negative spacer sonication culture but positive cultures of the rest of intraoperative samples. RESULTS: A total of 45 spacers were analysed: 10 were included in group A, 24 in group B and 11 in group C. The reoperation rate during the first year after the 2-stage revision surgery was 20%, 29.2% and 54.5% for each group, respectively, due to an infection in 10%, 20.8% and 45.5%. Spacers were colonised in all cases by low virulent micro-organisms. CONCLUSION: In our study, bacterial colonisation of the spacer is not associated with a higher rate of reoperation. The group of patients with positive intraoperative cultures during the second-stage had the highest reoperation rate.

Acute medullar compression secondary to a septic arthritis of a thoracic facet joint: a case report and review of literature.

INTRODUCTION: Septic arthritis of a facet joint (SAFJ) is a rare entity and frequently underdiagnosed. It is most frequently localised in the lumbar segment. CASE PRESENTATION: A 48-year-old woman presented at our emergency room with a chief complaint of lumbar pain and perineal hypoesthesia. An urgent lumbar Magnetic Resonance Imaging (MRI) was performed showing no signs of compressive pathology. Intravenous painkillers were administered improving her clinical symptoms, so she was discharged from the emergency department to be followed at our out-patient clinic. After 12 h, the patient presented again referring an acute loss of strength in her lower limbs and paresthesias at a T10 sensitive level. Due to the severity of the symptoms, we performed an urgent dorsal MRI that showed a septic arthritis of the left T8-T9 facet joint and an epidural abscess causing a medullar compression. Blood cultures were performed before surgical treatment. An urgent laminectomy of T8 and debridement of the abscess were performed. Intraoperative microbiology and blood cultures were positive for Streptococcus constellatus. After surgery, the patient presented a progressive improvement of her symptomatology. DISCUSSION: Physicians should have in mind and rule out this clinical entity to avoid severe consequences that a misdiagnosed SAFJ could develop.