Philippe Leonard

Dislocation After Total Hip Arthroplasty Using Hueter Anterior Approach

A prospective study including 1764 hips has been carried out to evaluate the frequency of dislocation while using the Hueter anterior approach and the correlated factors. The dislocation group was compared with the patients without dislocation. We observed 27 dislocations (1.5%). The dislocation rate when using 28 mm head diameter was 0.5%. Two patients underwent a revision for recurrent dislocations. Correlated factors for dislocation were male sex, high body mass index, etiology of osteonecrosis, low head diameter, high bleeding, and low postoperative ROM. Dislocation risk while using Hueter approach is one of the lowest in the literature. The main disadvantages are the necessity for a specific orthopedic table and a more difficult exposure of the femur.

Mycobacterium xenopi spinal infections after discovertebral surgery: investigation and screening of a large outbreak

BACKGROUNDnMycobacterium xenopi spinal infections were diagnosed in 1993 in patients who had undergone surgical microdiscectomy for disc hernia, by nucleotomy or microsurgery, in a private hospital. Contaminated tap water, used for rinsing surgical devices after disinfection, was identified as the source of the outbreak. Several cases were recorded in the 4 years after implementation of effective control measures because of the long time between discectomy and case detection. The national health authorities decided to launch a retrospective investigation in patients who were exposed to M xenopi contamination in that hospital.nnnMETHODSnMailing and media campaigns were undertaken concurrently to trace exposed patients for spinal infections. Patients were screened by magnetic resonance imaging (MRI), and the scans were reviewed by a radiologist who was unaware of the diagnosis. Suspected cases had discovertebral biopsy for histopathological and bacteriological examination.nnnFINDINGSnOf 3244 exposed patients, 2971 (92%) were informed about the risk of infection and 2454 (76%) had MRI. Overall, 58 cases of M xenopi spinal infection were identified (overall cumulative frequency 1.8%), including 26 by the campaign (mean delay in detection 5.2 years, SD 2.4, range 1-10 years). Multivariate analysis showed that the risk of M xenopi spinal infection was related to nucleotomy and high number of patients per operating session.nnnINTERPRETATIONnFailures in hygiene practices could result in an uncontrolled outbreak of nosocomial infection. Patients who have been exposed to an iatrogenic infectious hazard should be screened promptly and receive effective information.

One-Stage Exchange Arthroplasty for Chronic Periprosthetic Hip Infection: Results of a Large Prospective Cohort Study

BACKGROUNDnExchange arthroplasty of one or two stages is required for the treatment of chronic periprosthetic joint infections. Two-stage exchange is costly and has high morbidity with limited patient mobility between procedures. One-stage exchange has been promoted by several European teams as the preferred alternative. The aim of this study was to prospectively analyze the outcome of patients with a periprosthetic hip infection treated with one-stage exchange arthroplasty.nnnMETHODSnWe performed a prospective cohort study in a French referral center for osteoarticular infections including all periprosthetic hip infections treated with one-stage exchange arthroplasty from November 2002 to March 2010. Direct exchange was performed in chronic periprosthetic hip infection with no or minor bone loss and preoperative identification of a microorganism from joint fluid aspirate. No antibiotic-loaded bone cement was used. Antibiotic therapy was administered for twelve weeks: intravenously for four to six weeks, followed by an oral regimen for six to eight weeks. Follow-up was a minimum of two years. The following events were noted: relapse, new infection, joint revision for mechanical reasons, and periprosthetic hip infection-related and unrelated deaths.nnnRESULTSnOne hundred and fifty-seven patients with periprosthetic hip infections with a median infection duration of 258 days (interquartile range, 120 to 551 days) prior to our index surgical procedure for infection were included. Periprosthetic hip infection occurred in ninety-nine cases of primary hip arthroplasty, twenty-seven cases of revision arthroplasty, and thirty-one cases in which the periprosthetic hip infection had been treated previously. A difficult-to-treat organism was isolated in fifty-nine cases (38%). After a median follow-up of 41.6 months (interquartile range, 28.1 to 66.9 months), two relapses, six new infections, nine revisions for mechanical reasons, two related deaths, and nineteen unrelated deaths occurred.nnnCONCLUSIONSnOne-stage exchange arthroplasty is an effective surgical procedure in patients with periprosthetic hip infection who have good bone quality. Precise identification of the microorganism(s) and prolonged administration of appropriate intravenous antibiotic therapy are key factors for successful treatment.

Contribution of routine joint aspiration to the diagnosis of infection before hip revision surgery

OBJECTIVESnTo define the sensitivity and specificity of routine preoperative hip aspiration for diagnosing hip prosthesis infection (HPI) and to separately analyze subgroups with and without a clinical suspicion of HPI before aspiration.nnnMETHODSnFrom June 1994 to June 1997, all patients scheduled for hip revision surgery underwent aspiration of the hip under image intensifier guidance. Microbiological results were compared between these preoperative specimens and the intraoperative specimens. The reason for surgery was either a clinical suspicion of HPI or pain suggesting loosening.nnnRESULTSnThe study patients had had multiple surgical procedures. HPI was suspected clinically in 39.4% of cases. Of the 109 patients who underwent aspiration, 54 had true-negative results, nine had false-negative results, and 44 had true-positive results (there were no false-positive results), yielding a sensitivity of 83% and a specificity of 100%. Diagnostic efficiency was 91.6%, positive predictive value was 100%, and negative predictive value was 85.7%. In the subset of 43 patients with a clinical suspicion of HPI, aspiration identified all the causative organisms in 60.5% of cases. Of the 66 patients with no clinical suspicion of HPI, 12 had HPI, and aspiration provided the diagnosis preoperatively in seven of these patients, radically changing their management plans. Restricting routine aspiration to patients whose prosthesis had been implanted within the last 5 years or whose erythrocyte sedimentation rate (ESR) was above 30 mm/h would not have modified our findings.nnnCONCLUSIONSnHip aspiration before revision surgery for pain is effective in detecting HPI, which can simulate aseptic loosening. However, this investigation may be noncontributive in patients who have had their prosthesis for more than 5 years and whose ESR is less than 30 mm/h.

Molecular Detection and Identification of Agents of Eumycetoma: Detailed Report of Two Cases

ABSTRACT We describe two cases of eumycetoma in the legs. The infections could not be adequately diagnosed by classical mycology, but the causative agents were successfully identified as Madurella mycetomatis by species-specific PCR and DNA sequencing.

Valeur de la ponction systématique pour le diagnostic d’infection avant intervention sur une prothèse de hanche

Resume Objectif. – Definir sensibilite et specificite de la ponction de hanche preoperatoire systematique pour le diagnostic d’infection sur prothese. Puis etudier en sous-groupe selon la suspicion clinique d’infection avant la ponction. Methodes. – Entre juin 1994 et juin 1997, toute intervention sur une prothese de hanche a ete precedee d’une ponction, sous amplificateur de brillance : les resultats bacteriologiques de ces ponctions consecutives ont ete compares aux prelevements peroperatoires. L’intervention etait motivee soit par une suspicion clinique d’infection, soit par des douleurs de protheses faisant suspecter un descellement. Resultats. – La population etudiee etait multi-operee. On suspectait cliniquement l’infection dans 39,4 % des cas. Cent neuf ponctions ont ete realisees. Ponctions : 63 negatives dont neuf faux negatifs, 44 positives, pas de faux positif, sensibilite = 83 %, specificite = 100 %, efficacite diagnostique = 91,6 %, valeur predictive positive = 100 %, valeur predictive negative = 85,7 %. Dans la sous-population des patients suspects d’infection (n = 43), la ponction identifie l’ensemble des germes mis en cause dans 60,5 % des cas. Dans la sous-population des patients non suspects d’infection avant la ponction (n = 66), on releve 12 infections de prothese. La ponction a permis le diagnostic preoperatoire d’infection chez sept de ces patients, modifiant ainsi profondement leur prise en charge. La limitation de la ponction systematique aux seules protheses datant de moins de 5 ans ou en presence d’une vitesse de sedimentation > 30 mm a la premiere heure n’aurait pas modifie nos resultats. Conclusion. – La ponction de hanche avant reprise d’une prothese douloureuse est un examen efficace pour le depistage de l’infection de prothese qui peut mimer la symptomatologie d’un descellement simple. Il semble que l’on puisse eventuellement se passer de cet examen chez les patients ayant une prothese datant de plus de 5 ans et ayant une vitesse de sedimentation

Monitoring the one year postoperative infection rate after primary total hip replacement

PurposeInfection of a total hip replacement is potentially a devastating complication. Statistical process control methods have been generating interest as a means of improving the quality of healthcare, and we report our experience with the implementation of such a method to monitor the one year infection rate after primary total hip replacement.MethodInfection was defined as the growth of the same organism in cultures of at least two aspirates or intra-operative specimens, or growth of one pathogen in a patient with local signs of infection such as erythema, abscess or draining sinus tract. The cumulative summation test (CUSUM test) was used to continuously monitor the one year postoperative infection rate. The target performance was 0.5% and the test was set to detect twice that rate.ResultsOver the three year study period, 2006 primary total hip replacements were performed. Infection developed within one year after surgery in eight (0.4%) hips. The CUSUM test generated no alarms during the study period, indicating that there was no evidence that the process was out of control.ConclusionThe one year infection rate after primary total hip replacement was in control. The CUSUM test is a useful method to continuously ensure that performance is maintained at an adequate level.

Reprise de prothèse totale de hanche infectée : Changement en un ou deux temps ?☆

Summary Introduction Better outcomes have been reported for two-stage total hip arthroplasty (THA) revision for infection. However, one-stage revision arthroplasty remains an attractive alternative option since it requires only one operation. A decision tree has been developed by the authors in order to determine which type of surgical procedure can be performed safely. The goal of this study was to assess this decision tree for THA replacement in the case of a peri-prosthetic infection. Hypothesis A one-stage procedure may be as successful as a two-stage procedure, provided some criteria are fulfilled. Methods A prospective study included 84 patients, all diagnosed with infected THA who had prosthesis replacement. A one-stage exchange was performed in 38 cases and a two-stage procedure in 46 cases. A two-stage procedure was decided in the case of important bone loss or un-identified germ. Post-operatively, patients received intravenous antibiotics (6 weeks), then oral antibiotics (6 weeks). The main evaluation criterion was the rate of infection eradication at 2 years minimal follow-up since surgery. If new infection was suspected, a hip aspiration was performed to determine whether it was non-eradication (same germ) or a new re-infection (other germ) which was not considered as a failure. Results The initial infection was cured in 83 out of 84 patients (98.8%), 38 (100%) for the one-stage group and 45 (97.8%) for the two-stage group. Three patients were re-infected with different germs in the two-stage group. Eighty out of 84 (95.2%) patients were infection free, all patients (100%) of the one-stage group and 42 patients (91.3%) of two-stage group. Discussion If some selection criteria were respected, a high success rate in THA replacement for infection may be achieved with a one-stage procedure. It permits to reduce the costs with no loss of chance for the patients. The decision tree was validated. Level of evidence Level III, prospective case control study.