Luis Pulido

Periprosthetic Joint Infection: The Incidence, Timing, and Predisposing Factors

AbstractPeriprosthetic joint infection is one of the most challenging complications of joint arthroplasty. We identified current risk factors of periprosthetic joint infection after modern joint arthroplasty, and determined the incidence and timing of periprosthetic joint infection. We reviewed prospectively collected data from our database on 9245 patients undergoing primary hip or knee arthroplasty between January 2001 and April 2006. Periprosthetic joint infections developed in 63 patients (0.7%). Sixty-five percent of periprosthetic joint infections developed within the first year of the index arthroplasty. The infecting organism was isolated in 57 of 63 cases (91%). The most common organisms identified were Staphylococcus aureus and Staphylococcus epidermidis. We identified the following independent predictors for periprosthetic joint infection: higher American Society of Anesthesiologists score, morbid obesity, bilateral arthroplasty, knee arthroplasty, allogenic transfusion, postoperative atrial fibrillation, myocardial infarction, urinary tract infection, and longer hospitalization. This study confirmed some previously implicated factors and identified new variables that predispose patients to periprosthetic joint infection. Level of Evidence: Level II, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.

In Hospital Complications After Total Joint Arthroplasty

Total joint arthroplasty is a safe and successful procedure. However, numerous complications may present after elective arthroplasty. This study prospectively collected data on systemic and local in hospital complications after 15383 joint arthroplasties, which included 8230 total hip arthroplasties and 7153 total knee arthroplasties. In general, the incidence of complications was higher after knee arthroplasty, simultaneous bilateral surgery, and revision surgery. There were 22 (0.16%) deaths in this cohort. We identified 486 major systemic complications, the most common was pulmonary embolism (152), followed by tachyarrhythmia (92) and acute myocardial infarction (36). There were 109 major local complications, including 16 vascular injuries, 29 peripheral nerve injuries, 25 periprosthetic fractures, and 18 dislocations. Total joint arthroplasty, despite its success, can be associated with rare serious and life-threatening complications. This study provides a baseline of complications that can occur after elective joint arthroplasty.

The use of receiver operating characteristics analysis in determining erythrocyte sedimentation rate and C-reactive protein levels in diagnosing periprosthetic infection prior to revision total hip arthroplasty

BACKGROUND Periprosthetic infection (PPI) is a difficult complication in total joint arthroplasty, and while erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) are acute phase reactants thought to be of high predictive value for diagnosing infection, no clear cut-off values have been defined. The current study aimed to determine the cut-off values for ESR and CRP that improve clinical differentiation between aseptic failure and PPI in total hip arthroplasty (THA). METHODS Four hundred and seventy-nine patients who underwent revision THA for either aseptic mechanical failure or PPI during the period of 2000 to 2005 were included in the study. Specific exclusion criteria were applied to eliminate inflammatory or other confounding conditions. All patients underwent preoperative testing of ESR and CRP. Receiver operating characteristic (ROC) curves were constructed to determine maximum sensitivity and specificity. RESULTS Patients with PPI had significantly higher ESR and CRP values compared to patients undergoing revision for aseptic etiologies. An ESR threshold of 30 mm/h gave a sensitivity of 94.3% and a CRP threshold of 10 mg/l gave a sensitivity of 91.1%. Combining both ESR and CRP cut-offs for a positive diagnosis increased the sensitivity to 97.6%. However, when calculated by ROC analysis, the predictive cut-offs equated to 31 mm/h for ESR and 20.5 mg/l for CRP. CONCLUSIONS The gold standard for diagnosing PPI remains bacterial culture, but sensitivity is negatively affected by prior antibiotic exposure, strongly adherent bacteria, slow growing persisters, and biofilms. ESR and CRP are reflective of systemic changes in infection and pose an attractive, less invasive alternative with reasonable sensitivity and specificity. The current study is the first to identify ideal cut-off values for ESR and CRP in THA patients, providing an optimum balance between sensitivity and specificity based on ROC curves.

Cementless acetabular revision: past, present, and future : Revision total hip arthroplasty: the acetabular side using cementless implants

BackgroundAcetabular revision is probably the most difficult aspect of hip reconstructive surgery. Although the majority of acetabular revisions can be performed using an uncemented hemispherical acetabular device with ancillary fixation, patients with severe acetabular deficiencies and poor bone quality require more complex alternatives for revision. The limitations of traditional cementless acetabular implants has promoted the development of improved methods of fixation and revision techniques. Highly porous metals have been introduced for clinical use in arthroplasty surgery over the last decade. Their higher porosity and surface friction are ideal for acetabular revision, optimising biological fixation. The use of trabecular metal cups in acetabular revision has yielded excellent clinical results.PurposeThis review focuses on the use of cementless implants for acetabular revision. The use of trabecular metal cups, augments, jumbo cups, oblong cups, cages, and structural grafting are also discussed.

Microbiological, clinical, and surgical features of fungal prosthetic joint infections: a multi-institutional experience.

Periprosthetic joint infection is one of the most dreaded and complex complications of total joint arthroplasty. Periprosthetic joint infection is now the major cause of failure following total knee arthroplasty1 and the third most common cause of failure following total hip arthroplasty2. It is estimated that the prevalence of periprosthetic joint infection may be on the rise3. A wide variety of pathogens are known to cause periprosthetic joint infection, with the majority of infections being caused by gram-positive bacteria, especially staphylococcal species4,5. The treatment of a confirmed periprosthetic joint infection often includes the need for surgical intervention, and two-stage exchange arthroplasty is the most common mode of surgical treatment in North America. Two-stage exchange arthroplasty relies on removal of all foreign material and insertion of an antibiotic-impregnated cement spacer for the purpose of delivering high doses of antibiotics locally in the interval of time between the resection arthroplasty and subsequent reimplantation. Periprosthetic infection with fungi, although rare, represents a diagnostic and therapeutic challenge to which clear guidelines have not yet been established. It is not known if the protocol for treatment of a bacterial periprosthetic joint infection can also be applied in the same manner to fungal infections. Patients with fungal periprosthetic joint infection are believed to be a different type of host with decreased cellular immunity, mostly due to an underlying cause of immunosuppression, such as malignant disease, drug therapies (antineoplastic agents, corticosteroids, or immunosuppressive drugs), overuse or inappropriate use of antibiotics, and indwelling catheters (urinary or parenteral hyperalimentation). Other factors, such as diabetes, tuberculosis, intravenous drug use, and acquired immunosuppressive disease, are associated with an increased frequency of mycotic infection6. The lack of reliable antifungal medications for systemic and, in particular, local delivery poses a real challenge …

Vascular Injuries After Total Joint Arthroplasty

Vascular injuries, although highly feared, can occur after total joint arthroplasty, often resulting in legal suits. This study evaluates the circumstances related to vascular injuries after joint arthroplasty. Using prospectively collected data on 13,517 patients undergoing total joint arthroplasty at our institution, 16 (0.1%) vascular injuries were identified. Eleven injuries occurred after total knee arthroplasty (TKA) and 5 after total hip arthroplasty (THA). Indirect injury was the most common mechanism in TKA. In contrast, direct injury was most prevalent in THA. One patient died of complications related to vascular injury. Of 16 patients, 8 (50%) had launched a legal suit against the operating surgeon. There appears to be no further specific measure that can be taken to absolutely avoid this complication. Patient awareness regarding this real problem may play a role in defraying the high likelihood of legal suits associated with this complication.

Early Mortality after Modern Total Hip Arthroplasty

AbstractBecause of improvements in surgical technique, anesthesia, and rehabilitation, mortality after hip arthroplasty may be on the decline. The purpose of this study was to determine the 90-day mortality rate after uncemented total hip arthroplasty (THA) performed under regional anesthesia. We retrospectively reviewed 7478 consecutive patients undergoing cementless primary or revision THA between January 2000 and July 2006. Patient survivorship was established and causes of death were obtained by accessing the Social Security Death Index, Centers for Disease Control and Prevention National Death Index, and State Departments of Vital Statistics. There were two intraoperative deaths from cardiac arrest. The overall 30- and 90-day mortality rates were 0.24% (18 of 7478) and 0.55% (41 of 7478), respectively. Thirty-day mortality after primary THA was low at 0.13% (eight of 6272). The most common cause of death was cardiovascular-related. Mortality after modern THA seems to have remained very low despite the availability of this procedure to patients of all ages and comorbidities. Level of Evidence: Level IV, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.

Preoperative Anemia in Total Joint Arthroplasty: Is It Associated with Periprosthetic Joint Infection?

BackgroundAnemia is common in patients undergoing total joint arthroplasty (TJA). Numerous studies have associated anemia with increased risk of infection, length of hospital stay, and mortality in surgical populations. However, it is unclear whether and to what degree preoperative anemia in patients undergoing TJA influences postoperative periprosthetic joint infection (PJI) and mortality.Questions/PurposesWe therefore (1) determined the incidence of preoperative anemia in patients undergoing TJA; (2) assessed the possible association between preoperative anemia and subsequent PJI; and (3) explored the relationship between preoperative anemia with postoperative mortality.MethodsWe identified 15,722 patients who underwent TJA from January 2000 to June 2007. Anemia was defined as hemoglobin < 12 g/dL in women and hemoglobin < 13 g/dL in men. We determined the effect of preoperative anemia, demographics, and comorbidities on postoperative complications.ResultsOf the 15,222 patients, 19.6% presented with preoperative anemia. PJI occurred more frequently in anemic patients at an incidence of 4.3% in anemic patients compared with 2% in nonanemic patients. Thirty-day (0.4%), 90-day (0.6%), and 1-year (1.8%) mortality rates were not higher in patients with preoperative anemia. Forty-four percent of anemic patients received an allogenic transfusion compared with only 13.4% of nonanemic patients. Anemic patients had increased hospital stays averaging 4.3 days compared with 3.9 days in nonanemic patients. Anemia did not predict cardiac complications.ConclusionOur data demonstrate that preoperative anemia is associated with development of subsequent PJI. Preoperative anemia was not associated with 30-day, 60-day, or 1-year mortality in this cohort.Level of EvidenceLevel III, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.

The rise in the incidence of pulmonary embolus after joint arthroplasty: is modern imaging to blame?

In recent years, there has been an apparent increase in the incidence of pulmonary embolus after joint arthroplasty at our institution. We hypothesized the use of sophisticated imaging modalities such as the multidetector computed tomography scan, with better sensitivity, resulted in an apparent increase in the incidence of pulmonary embolus. We studied all patients with pulmonary embolus after joint arthroplasty between 2000 and 2005. The incidence of pulmonary embolus increased from 0.21% (six of 2859) when VQ scan was the modality of choice to 0.98% (50 of 5095) during the time spiral computed tomography was used to 1.72% (89 of 5179) in recent years when multidetector computed tomography was used. Despite the apparent increase in pulmonary embolus, we observed no change in mortality during the study period. Surgeons should be aware of the challenges sophisticated imaging modalities in general and modern imaging introduce for pulmonary embolus in particular. Extremely sensitive imaging tests with unknown specificity have resulted in an increase in diagnosed pulmonary embolus. However, diagnosing pulmonary embolus generates implications for further treatment such as prolonged anticoagulation and/or inferior vena cava filter insertion with potential for catastrophic complications. The challenge is to distinguish which require treatment and which do not.Level of Evidence: Level II, prognostic study. See the Guidelines for Authors for a complete description of levels of evidence.

Clostridium difficile infection after total joint arthroplasty: who is at risk?

Clostridium difficile-associated diarrhea is a recognized postoperative complication. However, the exact risk factors for this condition after total joint arthroplasty (TJA) remain unknown. This case-controlled study intended to identify the predisposing factors for this condition. There were 16 cases of C difficile infections after 9880 TJA (0.16% incidence) between January 2001 and May 2006 at our institution. The cases were matched with 32 controls for month/year of surgery and surgeon. This study suggests that patients with deteriorated physical status or those who receive greater than one antibiotic after surgery are at a higher risk for developing C difficile-associated diarrhea after TJA.