Aims

Currently, the most common approach for the management of a chronic PJI is a Two-Stage Replacement; because of success rates exceeding 90% when using an antibiotic impregnated cement spacer. Reliable information regarding the etiologic microorganism and its sensitivities is essential to select the antimicrobial therapy that should be used locally in the bone cement spacer during the first stage surgery as well as to select the appropriate microbiological systemic agent. Diagnostic algorithms focus to the importance of joint aspiration cultures although in the modern literature, preoperative joint aspiration has a broad range of values of sensitivity and the proportion of “dry-aspirations” is not well assessed. This low sensitivity of aspiration fluid samples in chronic-PJI is partly attributable to the fact that the majority of the microorganisms in these infections grow in biofilms attached to the implant. We have developed this biopsy technique in an effort to improve the identification rates of the causative organism.

Successful treatment of prosthetic joint infections (PJIs) requires surgical intervention and prolonged antimicrobial therapy (AT), although the most suitable management has not been clearly defined yet. The aim of the study is to review our experience in the management of AHPJIs.

From 01/01/2004 to 31/12/2006 all patients with PJIs were prospectively evaluated in 8 Spanish hospitals by the REIPI. We focused here on AHPJIs. Diagnostic of infection was based on clinical-microbiological evidence.

Forty-nine patients, 30 (61.2%) women, median age: 75.35 years (range: 31–92), were diagnosed of AHPJIs: 22 (44.8%) hips, 26 (53%) knees and 1 (2%) elbow implants. Following total joint replacement our patients had a median infection-free period of 4.9 years (range 0.3 to 18.7). The comorbidities were: 9 (18.3%) rheumatoid arthritis, 7 (14.3%) diabetes, and 6 (12.2%) chronic renal failure. Clinical features were acute in all cases: pain 100%, inflammatory signs 75.5%, and fever 70%. In 27 (55%) of the cases a distant previous infection caused by the same microorganism could be identified. The etiology was: S. aureus 18 (36.7%), streptococcal infections 13 (26.5%), coagulase-negative staphylococci 2 (4%), gram-negative bacilli 11 (22.4%), anaerobes 2 (4%), and mixed infections in 3 (6.1%) cases. Thirty (61.1%) patients underwent early drainage/debridement with retention of the implant, 11 (22.4%) two-stage replacement, 6 (12.5%) arthrodesis, 1 (2.1%) resection arthroplasty, and 1 unknown. Patients were treated with specific AT (median duration of 10.6 weeks) according to the isolated microorganism. At 1 year follow-up 25 (51%) were cured, 7 (14.3%) relapsed after a conservative approach (3 required an arthrodesis and 1 a two-stage replacement), 5 (10.2 %) died and 5 (10.2%) had a re-infection; in 7 the evolution was unknown.

AHPJs can be successfully treated in most cases with surgical debridement plus an antibiotic course. If a relapse is observed, removal of the prostheses could be necessary.

Introduction: Fusion of the knee joint should be the last option for salvage of infected total knee arthroplasty (TKA). Although knee arthrodesis implies lost of function, it is a successful treatment in eradicating the infection and in decreasing pain.

External fixation compression devices have been an excellent method for gaining fusion but, there is no documentation about its ability for obtaining adequate limb alignment with a stable fusion of the knee joint.

Material and Methods: We have retrospectively reviewed the results of knee arthrodesis after infection of TKA using an anteriorly placed unilateral external fixator. In addition, we have assessed patient self-satisfaction.

Postoperative radiographs have been evaluated to digitally measure loss of femoral and tibial bone stock using Engh radiological classification. Moreover, we have quantified tibiofemoral alignment and the section of bony fusion. Fusion of the knee joint was assessed with CT. Patients were interviewed and pain was graded using a Visual Analog Scale (VAS) and self-satisfaction as well as current health status using the 12-item social function survey form (SF12).

Results: From 1992 to 2003, 52 arthrodeses were done for treatment of infected TKA. The average age was 71 years (range, 37–83 years). Type III bone defect according with Engh classification, in femur and/or in tibia, was present in 50% of the patients. The average postoperative tibiofemoral alignment was 1.2° (SD 3.79). The mean time to fusion was 11.26 months (range, 3–30 months). Time to fusion was statistical related with severe bone loss and with the tibiofemoral contact section. The average score according VAS was 1.6 (SD 2.60).

Conclusions: Knee arthrodesis using a monolateral external fixator for infected TKA is an effective method to control infection as well as to obtain knee fusion and pain relief. Severe bone loss, frequently present in infected TKA, was found to be the most relevant factor in achieving tibiofemoral union. The individual clinical result according to SF12 shows a lower quality of life both for physical and mental components compare with general population.

Introduction: From 1972–2003, 205 arthroplasties of infected hips were performed in the Musculoskeletal Infectious Disease Unit of our hospital. Using as a basis the outcome for conventional one-and two-stage hip replacement with cemented implants and antibiotics performed in these patients, we designed a new two-stage hip replacement protocol using «personalized» solid spacers and non-cemented components.

Material and Methods: A total of 44 patients were treated with our protocol. Patient characteristics are described, as well as an elevated incidence of associated disease, the causative microorganisms, and therapy provided. Most of the cases had failed other treatment methods. Strict application of the protocol implied:

Previous identification of the infective microorganism

Results: Reactivation of infection occurred in only one case. The patient was cured with antibiotic administration. The remaining patients remained free of infection for a mean follow up period of 64.54 months (19.77–86.63 months). The septic process was erradicated in 96% of cases. Five-year implant survival was 100%.

Conclusions:

Cement with antibiotics is not essential for prosthesis reimplantation when replacement is performed in two-stage.

Introduction and Objectives: Arthrodesis of the knee is the method that most readily controls septic processes and results in a non-painful, stable knee joint. However, the disadvantages of this technique are shortening of the limb and a loss of joint function.

Materials and Methods: We present here our unit’s experience in the use of the Orthofíx ® transport system on the anterior surface to stabilise this type of arthrodesis. We used radiological techniques to evaluate the alignment and coaptation of the surfaces to be arthodesed. We also assessed functional capacity, postoperative patient satisfaction, rate of repeat arthrodesis, consolidation time, and complications associated with this method.

Results: According to our results, femorotibial arthrodesis with the bone transport system provides all the advantages of monolateral external fixation while allowing compression of the point of arthrodesis, achieving perfect coaptation, and providing extraordinary rigidity to the mounting.

Discussion and Conclusions: As with all other procedures, femorotibial arthrodesis has its complications. The complication directly related to knee arthrodesis is femorotibial non-union, which is correlated with a loss of bone stock, incomplete coaptation, poor alignment of the limb, persistent infection, and inadequate immobilisation. We believe this procedure produces a functional limb with significant relief of pain in most patients.