Metallosis in Sequelae of Prosthetic Revision for Ceramic Components Fracture: A Case Report with Clinical Presentation Mimicking Periprosthetic Hip Infection

Ceramic on ceramic total hip arthroplasties have been developed and widely used during last decades because of their long-term survival and biomechanical properties. One of the most dangerous complication of these implants is the fracture of the ceramic components. The management of this condition should be carefully planned and the choice of the new implant is crucial. We describe a rare case of severe hip synovitis due to massive metallosis in sequelae of mismanaged prosthetic revision for fracture of the ceramic acetabular liner with an unusual clinical presentation that simulate a periprosthetic infection.

Short-Term Follow-Up of the PROSTALAC Implant for Primary Total Hip Arthroplasty in Patients with an Infected Native/Total Hip

Infection after a total hip replacement (THR) is a significant complication for patients and is costly for health services. The two-stage Prosthesis with Antibiotic Loaded Acrylic (PROSTALAC) procedure has been the gold standard treatment for managing THR infections. The aim of this study is to evaluate using a one-stage PROSTALAC procedure as an alternative for patients who would otherwise not be able to undergo THR surgery due to a previous hip infection.We evaluated nine cases where the PROSTALAC implant was used in the native hip. The reasons for surgery, clinical results, and complications were reviewed. An Australian Orthopaedic Association National Joint Replacement Registry data report verified that no patients were revised outside of our local center.All patients reported symptomatic relief and satisfactory function, one patient had a peri-prosthetic fracture after experiencing a fall, and one patient underwent surgery for loosening of the joint. No cases were revised to another implant or had further infection. Minimum follow-up was 2 years.Our results suggest that this implant is useful in patients with osteoarthritis of the hip with a history of previous infection or chronic infection of the native hip.

Low frequency of local findings in periprosthetic hip infection caused by low-virulent bacteria compared to periprosthetic knee infection

Periprosthetic joint infection (PJI) is suspected when local findings such as pain, swelling, hyperthermia, and sinus tract are present. However, the frequency of these findings and the difference between hip and knee are unclear. This study compared the positive rates of local findings in periprosthetic hip infection (PHI) with periprosthetic knee infection (PKI), and aimed to identify potential risk factors associated with the frequency. One hundred one PJI (46 hips and 55 knees) fulfilled the 2018 Musculoskeletal infection society criteria were analysed retrospectively to assess the positive rates of each local finding. Patients were categorized into two groups based on the presence or absence of each local finding, and the influence of two potential risk factors [body mass index (BMI) and C-reactive protein (CRP)] was investigated. Causative bacterial species were divided into high and low-virulent groups, and then culture negative cases were included in low-virulent group. PHI had significantly lower rates of pain, swelling and hyperthermia compared to PKI. Overall, up to one-third of PHI had pain as only symptom. High BMI and low-virulent bacteria were associated with lower frequency of swelling and hyperthermia in PHI. CRP had no impact on positive rates of local findings. PHI was oligosymptomatic in a significant percentage of cases. This is particularly important in obese patients and infection by low-virulent bacteria.

A rare case of invasive non-typeable <i>Haemophilus influenzae</i> spondylodiscitis and periprosthetic joint infection

A non-typeable Haemophilus influenzae (NTHi) was responsible for an invasive infection including bacteremia, spondylodiscitis with epidural abscess, and periprosthetic hip infection in a 79-year-old woman, triggered by a superinfected ethmo-orbital mucocele. Surgical drainage and antibiotic therapy allowed recovery. PET-scan full cartography of NTHi infection dissemination enabled the discovery of spondylodiscitis. This rare cause of spondylodiscitis and periprosthetic joint infection suggests a complete work-up is unavoidable.

Infected hip prosthesis in patient with suspected Covid-19 infection

Background Infections following arthroplasty are one of the major risks during this type of surgery. Moreover, the outbreak of coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2 (Severe Acute Respiratory Syndrome CoronaVirus Disease 2), has developed into an unprecedented pandemic, posing enormous pressure on health-care providers around the world. Case presentation Four and half years after right hip arthroplasty, the patient came back to our attention with pain at the same hip. The instrumental examinations showed signs of cup detachment. After carefully analyzing the case, we decided to perform a sterile aspiration of the hip in the operating room under C-arm fluoroscopy. Microbiological examinations showed positivity for E. coli. The patient underwent surgery by which the prosthesis was removed and a spacer was implanted. A therapy with Cefotaxim 2 g three times a day for 6 weeks was then set, and then a total arthroplasty was performed. During this period, the COVID-19 pandemic occurred and therefore the patient received nasal-throat swabbing two times, and both yielded negative results. However, 1 week after the final surgery, his respiratory conditions deteriorated and chest X-ray and CT scan showed images of ground-glass opacification patterns (GGO). Due to the clinical symptoms and the characteristic images of the instrumental examinations, the patient was transferred to an observation ward. Thereafter, two more swab tests gave negative results. The patient was then transferred to the ward for patients with typical symptoms of COVID-19 but with negative swab tests for 2 weeks and was subsequently discharged home. Conclusion The purpose of this case report was to point out the correct treatment of a PJI after the outbreak of COVID-19. Despite the ongoing COVID-19 pandemic, the guidelines in the case of periprosthetic hip infection further confirmed the correct management of the patient.