Two-Stage Revision Arthroplasty for Periprosthetic Hip Infection: Mean Follow-Up of Ten Years.

BACKGROUND: Two-stage revision hip arthroplasty is the gold standard for treatment of patients with chronic periprosthetic joint infection (PJI), but few studies have reported outcomes beyond short-term follow-up. METHODS: A total of 155 patients who underwent two-stage revision arthroplasty for chronic PJI in 157 hips were retrospectively enrolled in this study between January 2001 and December 2010. The mean patient age was 57.5 years, the mean prosthetic age was 3.6 years, and the interim interval was 17.8 weeks. These patients were followed up for an average of 9.7 years. RESULTS: At the latest follow-up, 91.7% of the patients were free of infection. The mean Harris hip score improved significantly from 28.3 points before operation to 85.7 points at the latest follow-up. Radiographically, there was aseptic loosening of the stem or acetabular components in 4 patients. In the multivariate survival analysis using a Cox regression model, repeated debridement before final reconstruction, an inadequate interim period, bacteriuria or pyuria, and cirrhosis were found to be the independent risk factors for treatment failure. CONCLUSION: Our data show that two-stage revision hip arthroplasty provides reliable eradication of infection and durable reconstruction of the joint in patients with PJI caused by a variety of pathogens.

A modified cement spacer technique for infected total hip arthroplasties with significant bone loss.

Complications related to femoral spacers are common during addressing infected total hip arthroplasties by 2-stage revision. We evaluated 11 patients who had 2-stage revisions with massive bone loss after removal of the infected components by a trochanteric osteotomy. All femoral cement spacers were assembled on intramedullary nails. Femurs were protected by a plate, whereas acetabuli were augmented by a cage or roof ring depending on the remaining bone stock. This additional hardware was covered with antibiotic-impregnated cement. Infection was eradicated in 10 (90.9%) of 11 patients within 3.5 months in average. None of the patients had spacer fracture, periprosthetic fracture, or dislocation. Augmentation by hardware covered with antibiotic-impregnated cement is effective and may reduce complications until definitive treatment is performed.

THA after acetabular fracture fixation: is frozen section necessary?

BACKGROUND: Infection is uncommon after THA performed for failed acetabular fracture repair, despite a high reported incidence of culture-positive fixation implants. The use of frozen section analysis at the time of THA after acetabular fracture fixation surgery is unknown. QUESTIONS/PURPOSES: We asked whether frozen section analysis predicted occult infection after THA performed after acetabular fracture repair. METHODS: We retrospectively reviewed the charts of 43 of 49 patients with prior acetabular fracture fixation who had intraoperative frozen section and culture data from a conversion THA between 2002 and 2010. The average age of patients at fracture was 53 years; conversion was performed after an average of 553 days (median, 369 days; range, 51-2951 days). Five patients had an infection after acetabular fracture surgery (three deep, two superficial). At conversion we obtained an average of three frozen section specimens per patient; 10 specimens in eight patients contained greater than 10 polymorphonuclear cells/high-power field. The minimum followup was 51 days (median, 256 days; range, 51-2085 days). RESULTS: Five patients had positive intraoperative cultures, three of whom had a positive frozen section. All patients who had prior deep infection developed positive intraoperative cultures. The sensitivity, specificity, positive predictive value, and negative predictive value of frozen section analysis were 0.60, 0.87, 0.38, and 0.94, respectively. CONCLUSION: Infection complicating THA after acetabular fracture repair is uncommon. A history of deep infection complicating the acetabular fracture surgery was the strongest predictor of infection. Frozen section analysis has a high specificity and negative predictive value. LEVEL OF EVIDENCE: Level III, diagnostic study. See Guidelines for Authors for a complete description of levels of evidence.

Complications encountered with the use of constrained acetabular prostheses in total hip arthroplasty.

At our department, 46 constrained acetabular components in 38 patients were placed successively for a period of 4 years. Indications included recurrent dislocation, septic and aseptic loosening with extensive bone loss, tumor surgery with extensive bone resection, and instability due to neurologic impairment. Because 2 cup failures and 10 dislocations were observed with the constrained devices at 4 to 7 years of follow-up, the authors started to use large-diameter metal-on-metal bearings for similar indications. A series of 36 such bearings in 38 patients revealed only one cup failure and one dislocation at 2 to 4 years of follow-up. Although the 2 series are different and therefore difficult to compare, the authors recommend judicious use of constrained devices because of the high failure rate (26%) and consideration of alternative options such as the use of large-diameter metal-on-metal bearings.

Brucellosis hip abscess without risk factor.

Brucellosis has become a rare entity in many industrialised countries, because of animal vaccination programs. We report a first case in the literature of Brucella abscess in the hip region observed in Switzerland in a subject without any clear risk factor, leading us to conclude that abscess formation can be a rare manifestation of brucellosis. Because it can present in many different forms and locations without having characteristic clinics, a high index of suspicion is needed for the diagnosis even if the patient is a healthy athlete with no clear way of obvious route for contamination, and this even more if all the common causes of athletic hip pain have been ruled out.

Removal of a well-fixed metal-metal hip resurfacing acetabular component.

Well-fixed metal-metal hip resurfacing components are removed for infection, instability, or hypersensitivity reactions. This article presents a technique for removal of a porous resurfacing acetabular component with minimal bone loss.

Viability of impacted bone allografts under metal mesh at the calcar in revision surgery of the hip.

Metal meshes are used in revision surgery of the hip to contain impacted bone grafts in cases with cortical or calcar defects in order to provide rotational stability to the stem. However, the viability of bone allografts under these metal meshes has been uncertain. We describe the histological appearances of biopsies obtained from impacted bone allografts to the calcar contained by a metal mesh in two femoral reconstructions which needed further surgery at 24 and 33 months after the revision procedure. A line of osteoid and viable new bone was observed on the surface of necrotic trabeculae. Active bone marrow between these trabeculae showed necrotic areas in some medullary spaces with reparative fibrous tissue and isolated reactive lymphocytes. This is interpreted as reparative changes after revascularisation of the cancellous allografts. These pathological findings are similar to those reported in allografts contained by cortical host bone and support the hypothesis that incorporation of morcellised bone under metal meshes is not affected by these devices.

Artritis séptica con destrucción de cadera por artritis reumatoide / Septic arthritis with hip destruction due to rheumatoid arthritis

Introducción. Se presenta el caso de una paciente diagnosticada de artritis reumatoide en su adolescencia, que desarrolló una artritis séptica en su cadera derecha. Caso clínico. La paciente presentaba una importante y grave destrucción articular a ese nivel, con una marcada protrusión acetabular. De inicio se instauró tratamiento antibiótico, procediendo a una resección tipo Girdle stone y lavado articular, para implantar posteriormente una prótesis total de cadera definitiva. Conclusión. Se remarca la necesidad de un diagnóstico precoz y desde el punto de vista terapéutico la elección de la técnica en dos tiempos

Introduction. A patient diagnosed as rheumatoid arthritis during adolescence developed septic arthritis of the right hip. Case report. The patient presented major destruction of the hip joint with marked acetabular protrusion. Antibiotics were given from the onset and treatment continued with Girdle stone resection and joint lavage followed by total hip replacement. Conclusion. The need for an early diagnosis and choice of the two-stage treatment technique are discussed

Contamination of banked femoral head allograft: incidence, bacteriology and donor follow up.

BACKGROUND: Allograft donations are not uncommonly found to be contaminated. The issue of contaminated donations from live donors at the time of surgery, and the significance of this to the patient in terms of subsequent sepsis of the arthroplasty, were examined. METHODS: The donations of femoral heads to the Queensland Bone Bank over a 9-year period were reviewed, and the incidence and bacteriology of contamination were detailed. Clinical outcomes were determined for donors who had positive cultures at the time of retrieval and they were compared with those of culture-negative donors. RESULTS: Between March 1987 and February 1996, 232 femoral heads were donated to the Queensland Bone Bank. Four specimens were sent for culture with each femoral head (surface swab of femoral head, acetabular swab, bone biopsy and capsule). In 51 cases, one or more positive cultures were obtained (22% contamination rate). The majority of organisms cultured were Staphylococcus epidermidis. One hundred and seventy donations came from surgery performed at the Princess Alexandra Hospital, and 40 femoral heads were considered contaminated. Deep infection was recorded in one of the 40 cases with contaminated donations and three out of 130 non-contaminated donations had subsequent septic episodes. CONCLUSION: The contamination rate detailed in the present report is higher than in most series. This may be due to the fact that four bacteriological specimens are taken to assess contamination. Two of these specimens are tissue samples which yielded more positive results than did the two swabs. All other series take no more than two bacteriological specimens, which are usually bone swabs. These are shown to have a poor yield of positive cultures. Therefore there is a significant underestimation of contamination rates by other bone banks. This has implications for the recipients of bone from those banks, particularly when the allograft material is not secondarily sterilized. This is important given increasing allograft usage, and the increasing numbers of revision joint arthroplasty and impaction grafting procedures being performed. Sterilization of all bone by irradiation to 25 kGy is recommended.

Insidious destruction of the hip by Mycobacterium tuberculosis and why early diagnosis is critical.

Tuberculosis has re-emerged as an important problem in the United States. More than 10 million people presently are infected with Mycobacterium tuberculosis in the United States alone. The symptoms at first presentation of the disease have become more diverse. With extrapulmonary manifestations, such as musculoskeletal infections, as the sole presenting sign, it often can be difficult to determine the correct diagnosis early in the course of the disease. The presenting symptoms, physical signs, and radiographic findings of intra-articular tuberculosis can mimic those of other intra-articular diseases, such as rheumatoid arthritis, osteoarthritis, and avascular necrosis. In view of the nonspecific findings early in course of the disease, tubercular infection should be considered in the differential diagnosis when there is insidious articular destruction. Failure to consider tuberculosis can lead to devastating outcomes otherwise preventable with today's chemotherapies.

Improved detection of infection in hip replacements. A currently underestimated problem.

Our aim was to determine if the detection rate of infection of total hip replacements could be improved by examining the removed prostheses. Immediate transfer of prostheses to an anaerobic atmosphere, followed by mild ultrasonication to dislodge adherent bacteria, resulted in the culture of quantifiable numbers of bacteria, from 26 of the 120 implants examined. The same bacterial species were cultured by routine microbiological techniques from only five corresponding tissue samples. Tissue removed from 18 of the culture-positive implants was suitable for quantitative tissue pathology and inflammatory cells were present in all samples. Furthermore, inflammatory cells were present in 87% of tissue samples taken from patients whose implants were culture-negative. This suggests that these implants may have been infected by bacteria which were not isolated by the techniques of culture used. The increased detection of bacteria from prostheses by culture has improved postoperative antibiotic therapy and should reduce the need for further revision.