Aim

When a prosthetic joint infection (PJI) is suspected, guidelines recommend performing periprosthetic samples, at least one for histopathological examination and 3 to 6 for microbiological culture. The diagnosis of infection is based on the presence of neutrophil granulocytes whose number and morphology can be variable, resulting in definition of “acute” inflammation. The acute inflammation of periprosthetic tissue is supportive of infection. Since 2007, in our hospital, for all patients with suspected PJI who underwent surgery, from each sample taken by the surgeon, one part has been sent to the pathologist and the other one to the microbiologist. Our aim was to compare histopathological to microbiological results from samples taken intraoperatively at the same site.

To evaluate the value of the use of massive prostheses in periprosthetic infections both in one stage and two stages procedures

Between 2008 and 2014, 236 revisions for PJI had been performed in our hospital by the same surgeon. For the most complex cases, we decided to introduce megaprostheses in our practice in 2011.

We report a prospective series of 33 infected patients treated between 2011 and the end of 2014, 14 male and 19 female with on average 67.9 years old (38–85) Infection involved TKA in 22 cases (17 TKA revisions, 4 primary TKA), THA in 9 cases (6 revisions, 3 primary THA), a femoral pseudo-arthrosis with posttraumatic gonarthrosis in one case and a septic humeral pseudoarthrosis in one case. We used a total femoral component for two patients: the first one for a hip PJI with extended diaphyseal bone loss and multiples sinus tracks, and the second one for a massive infected knee prosthesis used in a knee reconstruction for liposarcoma.

We used one stage procedures in 20 cases (8 hips, 12 knees, 1 shoulder) and two stages in 13 cases (12 knees and 1 hip). Additional technics included 3 massive extensor system allografts, two local flaps. Perioperative hyperbaric treatment was used for 2 patients.

The average follow up is 19.8 months (6–48 months). The most frequent complications were wound swelling and delayed healing in 8 cases;). In 3 cases of one stage surgery a complementary debridement was necessary in the three weeks after the surgery with always a good local and infectious evolution. VAC therapy was used in four cases with good results. We report one early postoperative dead.

In summary, the use of massive prostheses in PJI is a good option for complex cases. It can be a good alternative to knee arthrodesis. These components must be used preferentially for older patients, in cases of extreme bone loss or extensive osteomyelitis to secure the bone debridement and the quality of the reconstruction.

In our series, the one stage procedure is a validated option even by using complementary technics as bone allografts, extensor system allografts or flaps. We believe the two stages surgery is a secondary option, particularly when soft tissues status is compromised before or after the debridement, and mostly for the knees. The longevity of the implantation must be evaluate by a long term follow up.

Tc 99m labelled leukocytes scintigraphy (LLS) could be useful for the diagnosis of bone and joint infections. The aim of our study was to evaluate its performances specifically in the diagnosis of prosthetic joint infection (PJI).

We conducted a multicenter -7 year- retrospective study including 164 patients with suspected PJI who underwent surgical treatment. In each case, 5 intraoperative samples were taken. Diagnosis of infection was confirmed if two or more samples yielded the same microbial agent. LLS was considered as « positive » if an accumulation of leukocytes was observed in early stage and increased in late stage (24 hours). Among these patients, 123 had also a bone scintigraphy.

A total of 168 PJ were analyzed: 150 by in vitro polymorphonuclear labelled leukocytes scintigraphy (PLLS) and 18 by anti-granulocytes antibodies labelled leukocytes scintigraphy (LeukoScan®). Location of PJ were: hip (n = 63), knee (n = 71), miscellaneous (n = 4). According to microbiological criteria 62 hip prosthesis and 48 knee prosthesis were considered as infected. Sensitivity (Se), Specificity (Sp), Positive Predictive Value (PPV) and Negative Predictive Value of PLLS were: 72%, 60%, 80% and 47%. Se of LLS was higher for knee PJI (87%) than for hip PJI (57%) [p = 0.002]. Although Sp was higher for hip PJI (75%) than for knee PJI (52%) [p = 0.002]. The lowest Se was found for coagulase negative staphylococci (70%) and the highest for streptococci (87.5%). However the difference of Se between bacteria was not significant. Regarding bone scintigraphy, Se, Sp, PPV and NPV were: 94%, 11%, 65% and 50%.

In our study, performances of LLS were rather low and varied according to the location of infection. Differences of LLS Se between bacteria was not significant. Bone scintigraphy has a high Se but lacks Sp.

To evaluate a innovate one stage procedure of the PJI knee treatment using computed assisted guidance. Our objectives; to increase the functional results by optimizing the anatomical joint reconstruction and to verifie if CAS help to simplifie and standardize these complex surgeries

It's a prospective, single surgeon study. Since septembre 2011, 41 patients treated for chronic knee PJI in a one stage revision (one of them had a ipsilateral chronic knee arthritis). For all of them, a computed assisted guidance, the ExactechGPS® system was used. This system offers the possibility to define specific profiles to performe primary TKA surgeries. A personnalized profile of revision was created.

All surgeries were performed with the same protocole; independently of the type of germ, with no use of tourniquet, no drainage by performing the same debridement procedure step by step and by using the same knee components

27 males, 14 female with 26 PJI of primary TKA, one infected unicompartimental prosthesis and 15 PJI of first revised TKA has been treated. The average age was 71 years old (55–87). The time of surgery was on average 135 mn (120 – 195 mn). The average time of hospitalization was 10 days (7–16). The average follow up was 20,9 months (6–47 months). The ROM were on average 114,7% (90°–130°), None post operative HKA outliers were reported.

3 patients presented a failure of the PJI treatment (one after a local open traumatism, one diabetic patient, one after a early revision for mechanical complication). None specific CAS complications and no failure of the CAS procedures are reported. As surgeon, CAS simplified the management of the bone loss after debridement and the control of the differents parameters (HKA, external femoral rotation, ligamentary balancing, lign joint…) by a real time feedback. we changed our practise by using more constraint condylar component instead hinge prostheses

With a rate of success of 92,7% at this follow up, the one stage option appears to be valided. Using CAS is a safe option with no specific complication. It increases the quality of the ROM, a earlier functional recovery and a better middle term clinical result. Both combined, It should be a optimal medicoeconomical solution.

compared revision using mechanical ancillary.

PJI du to Enterobacter cloacae are rare and often severe. The aim of our study is to define the history of patients with such infections and their outcome.

We conducted a retrospective monocentric study in an orthopedic unit where complex bone and joint infections are supported. From 2011 to 214 we selected patients with E. cloacae PJI based on data from the microbiology laboratory. In their files we collected information on their background, their medical and surgical history, antibiotics they received in the year before infection, the suspected portal of entry, the management and the outcome.

Twelve patients were included, 7 male and 5 female. PJI was located to the hip in 8 cases, the knee in 3 cases and the ankle in one case. The average time between the placing of the first prosthesis and infection was 3 years. Eleven patients had one or more surgery for previous PJI. The average time elapsed since the last surgery was 30 days. Eleven patients had been treated with antibiotic combinations for at least 6 weeks, in the year before E cloacae infection. A portal of entry was identified only two times: urinary tract infection in one patient and catheter-related infection in one patient. Antibiotics the more often prescribed were carbapenems (n = 5) and cefepime (n = 4), each combined with quinolones (n =4) or fosfomycin (n = 3). Two patients required an additional debridement within an average of 18 days. Infectious outcome was favorable in 8 cases (67%) with a median duration of follow-up of 26 months. Two patients had a recurrent infection, one due to Streptococcus oralis and one to Candida albicans. One patient had a relapse of E cloacae infection. One patient died from unknown cause.

PJI infections due to E.cloacae usually occur early after prosthetic surgery, typically in patients with complex surgical history. Despite a high rate of multi-resistance to antibiotics, outcome may be favorable in a large majority of patients.