Miguel M. Gomez

The Fate of Spacers in the Treatment of Periprosthetic Joint Infection

BACKGROUND Two-stage exchange arthroplasty remains the preferred method to treat periprosthetic joint infection. The aim of this study was to investigate the clinical course of periprosthetic joint infection following resection arthroplasty and insertion of a spacer. METHODS Our institutional database was used to identify 504 cases of periprosthetic joint infection (326 knees and 178 hips) treated with resection arthroplasty and spacer insertion as part of a two-stage exchange arthroplasty. A review of the patient charts was performed to extract information relevant to the objectives of this study that included the details of the clinical course following resection arthroplasty. RESULTS The mean follow-up duration after initial spacer implantation was 56.2 months. Reimplantation occurred in the joints of 417 (82.7%) of 504 cases. Of these 417 cases, 329 (78.9%) had a minimum one-year follow-up, and 81.4% of these had successful treatment. The mean duration from resection arthroplasty to reimplantation was 4.2 months (range, 0.7 to 131.7 months). Sixty (11.9%) of the 504 joints required interim spacer exchange(s). Of the eighty-seven cases that did not undergo reimplantation, six (6.9%) required amputation, five (5.7%) underwent a Girdlestone procedure, four (4.6%) underwent arthrodesis, and seventy-two (82.8%) underwent spacer retention. Thirty-six patients died in the interstage period. CONCLUSIONS The commonly held belief that two-stage exchange arthroplasty carries a high success rate for the eradication of periprosthetic joint infection may need to be reexamined. A considerable number of patients undergoing the first stage of a two-stage procedure do not undergo a subsequent reimplantation for a variety of reasons or require an additional spacer exchange in the interim. Reports on the success of two-stage exchange should account for the mortality of these patients and for patients who never undergo reimplantation.

Preoperative Anemia Increases Postoperative Complications and Mortality Following Total Joint Arthroplasty

Single-institution, large case-controlled study examines the association between preoperative anemia and adverse outcomes following total joint arthroplasty (TJA). We collected data from our institutional database of patients who underwent primary and aseptic revision TJA. Only 2576 patients had anemia preoperatively, and 10,987 patients had hemoglobin within the normal range. Multivariate analysis was used to determine the effect of preoperative anemia on the incidence of medical complications, infection, LOS and mortality. Anemic patients had a higher rate of complications (odds ratio 2.11), namely cardiovascular 26.5% versus 11.8%, and genitourinary 3.9% versus 0.9%. Our study confirms that patients with preoperative anemia are likely to exhibit a higher incidence of postoperative complications following TJA. Preoperative optimization may be needed in an effort to reduce these complications.

Stiffness after Total Knee Arthroplasty

Stiffness after total knee arthroplasty (TKA) adversely affects outcome and impacts patient function. Various risk factors for stiffness after TKA have been identified, including reduced preoperative knee range of motion, history of prior knee surgery, etiology of arthritis, incorrect positioning or oversizing of components, and incorrect gap balancing. Mechanical and associated causes, such as infection, arthrofibrosis, complex regional pain syndrome, and heterotopic ossification, secondary gain issues have also been identified. Management of stiffness following TKA can be challenging. The condition needs to be assessed and treated in a staged manner. A nonsurgical approach is the first step. Manipulation under anesthesia may be considered within the first 3 months after the index TKA, if physical therapy fails to improve the range of motion. Beyond this point, consideration should be given to surgical intervention such as lysis of adhesions, either arthroscopically or by open arthrotomy. If the cause of stiffness is deemed to be surgical error, such as component malpositioning, revision arthroplasty is indicated. The purpose of this article is to evaluate the various aspects of management of stiffness after TKA.

Patients With Failed Prior Two-Stage Exchange Have Poor Outcomes After Further Surgical Intervention

BACKGROUND Failure of 2-stage exchange arthroplasty for the management of periprosthetic joint infection (PJI) poses a major clinical challenge. There is a paucity of information regarding the outcomes of further surgical intervention in these patients. Thus, we aim to report the clinical outcomes of subsequent surgery for a failed prior 2-stage exchange arthroplasty. METHODS Our institutional database was used to identify 60 patients (42 knees and 18 hips), with a failed prior 2-stage exchange, who underwent further surgical intervention between 1998 and 2012, and had a minimum 2-year follow-up. A retrospective review was performed to extract relevant clinical information, including mortality, microbiology, and subsequent surgeries. Musculoskeletal Infection Society criteria were used to define PJI, and treatment success was defined using Delphi criteria. RESULTS Irrigation and debridement (I&D) was performed after a failed 2-stage exchange in 61.7% of patients; 56.8% subsequently failed. Forty patients underwent an intended second 2-stage exchange; 6 cases required a spacer exchange. Reimplantation occurred only in 65% of cases, and 61.6% had infection controlled. The 14 cases that were not reimplanted resulted in 6 retained spacers, 5 amputations, 2 PJI-related mortalities, and 1 arthrodesis. CONCLUSION Further surgical intervention after a failed prior 2-stage exchange arthroplasty has poor outcomes. Although I&D has a high failure rate, many patients who are deemed candidates for a second 2-stage exchange either do not undergo reimplantation or fail after reimplantation. The management of PJI clearly remains imperfect, and there is a dire need for further innovations that may improve the care of these patients.

Positive Culture During Reimplantation Increases the Risk of Subsequent Failure in Two-Stage Exchange Arthroplasty

BACKGROUND It is strongly recommended that tissue and synovial fluid culture samples be obtained during reimplantation performed as part of a 2-stage exchange arthroplasty. The rate of positive cultures during reimplantation and the influence of positive cultures on subsequent outcomes, to our knowledge, are unknown. This study was designed to determine the rate of positive cultures during reimplantation and to investigate the association between positive cultures at reimplantation and subsequent outcomes. METHODS We retrospectively reviewed the data of 259 patients who met the Musculoskeletal Infection Society criteria for periprosthetic joint infection (PJI) and who underwent both stages of 2-stage exchange arthroplasty at our institution from 1999 to 2013. Among these patients were 267 PJIs (186 knees and 81 hips); 33 (12.4%) had ≥1 positive culture result at reimplantation. Treatment failure was assessed according to the Delphi-based consensus definition. Logistic regression analysis was performed to assess the predictors of positive culture and risk factors for failure of 2-stage exchange arthroplasty. RESULTS Of the 33 cases with PJI, 15 (45.5%) had a subsequent failure of the 2-stage exchange arthroplasty compared with 49 (20.9%) of the cases that were culture-negative at reimplantation. When controlling for other variables using multivariate analyses, the risk of treatment failure was higher (odds ratio = 2.53; 95% confidence interval [CI] = 1.13 to 5.64) and reinfection occurred earlier (hazard ratio = 2.00; 95% CI = 1.05 to 3.82) for the cases with a positive culture during reimplantation. The treatment failure rate did not differ (p = 0.73) between cases with ≥2 positive cultures (36.4%) and 1 positive culture (50%). CONCLUSIONS Positive intraoperative culture at the time of reimplantation, regardless of the number of positive samples, was independently associated with >2 times the risk of subsequent treatment failure and earlier reinfection. Surgeons should be aware that a positive culture at the time of reimplantation independently increases the risk of subsequent failure. LEVEL OF EVIDENCE Prognostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Surgical site infection and transfusion rates are higher in underweight total knee arthroplasty patients

Background Underweight (UW) patients undergoing total hip arthroplasty have exhibited higher complication rates, including infection and transfusion. No study to our knowledge has evaluated UW total knee arthroplasty (TKA) patients. We, therefore, conducted a study to investigate if these patients are at increased risk for complications, including infection and transfusion. Methods A case-control study was conducted using a prospectively collected institutional database. Twenty-seven TKA patients were identified as UW (body mass index [BMI] < 18.5 kg/m2) from 2000-2012 and were matched for age, gender, date of surgery, age-adjusted Charlson comorbidity index, rheumatoid arthritis, and diabetes. These patients were compared to 81 normal weight patients (BMI 18.5-24 kg/m2). Demographic variables were compared, along with wound complications, surgical site infection (SSI), blistering, deep vein thrombosis, pulmonary embolism, transfusion, revision, flexion contracture, hematoma formation, and patellar clunk. Results The average BMI was 17.1 kg/m2 (range 12.8-18.4) for UW and 23.0 kg/m2 (range 19.0-25.0) for normal weight patients (P < .001). UW TKA patients were more likely to develop SSIs (3/27, 11.1% vs 0/81, 0.0%, P = .01) and were more likely to require transfusions (odds ratio = 3.4, confidence interval 1.3-9.1; P = .02). Conclusions Our study demonstrates that UW TKA patients have a higher likelihood of developing SSI and requiring blood transfusions. The specific reasons are unclear, but we conjecture that it may be related to decreased wound healing capabilities and low preoperative hemoglobin. Investigation of local tissue coverage and hematologic status may be beneficial in this patient population to prevent SSI. Based on the results of this study, a prospective evaluation of these factors should be undertaken.

Periprosthetic Infection: Management of Chronically Infected Total Knee Arthroplasty

Periprosthetic joint infection (PJI) is the most feared and challenging complication after total knee arthroplasty (TKA) due to the difficulty in diagnosis and treatment. The patient is exposed to multiple procedures, increasing the risk of complications, and finally compromising functional outcome. Currently, there is no gold standard test for PJI, and the final diagnosis is accomplished by combining clinical suspicion with inflammatory marker results. Two-stage exchange arthroplasty remains the preferred method of treatment for chronic PJI in TKA, with a high rate of success reported in literature. However, failures and complications in two-stage exchange can occur. There are no clarified guidelines to treat complications or treatment failures. Thus, each case should be individualized to offer options that match the patient’s expectations with what is achievable. The case report in this chapter represents the worst case scenario after a TKA, and is a reminder that the gold standard is far from perfect, while it outlines multiple instances a surgeon could encounter.

Total Knee Arthroplasty Associated Infections: Treatment Strategies

Periprosthetic joint infection (PJI) continues to challenge the orthopedic community. As the need for total knee arthroplasty (TKA) continues to increase and is more frequently being performed in younger patients, the absolute number of infected patients is expected to increase. Currently, infection after TKA is the leading reason for early readmission and the main cause of revision arthroplasty within the first two years after surgery. There is no perfect treatment option; rather, there are a variety of alternatives that carry their own set of benefits and flaws. Moreover, clinical results of these treatment options are always expected to be lower than the outcomes achieved after a primary TKA. The accuracy in selecting the appropriated treatment option for each patient is key for achieving positive results. Each case should be considered with all available evidence to successfully eradicate the infection and prevent reinfection. This chapter describes the different treatment options, their indications, steps, and the available up-to-date results for treating PJI after TKA.

Periprosthetic joint infection in total knee arthroplasty: current concepts

Periprosthetic joint infection (PJI) is currently one of the three main causes of readmission and the most frequent cause of revision following total knee arthroplasty (TKA). It remains the most challenging complication in adult joint reconstruction due to the difficulty in diagnosis and treatment. This review article provides an update on the most recent developments related to the field which include the introduction of a novel biomarker for diagnosis of PJI, a summary of the international consensus meeting on PJI, and other developments.