Aim. The aim of this study is to evaluate if the gentamycin elution from bone cement is influenced by the timing of application of the antibiotic powder. Method. This was an experimental in vitro study that compared the elution properties of different formulation of gentamycin from a commercially available hip, knee and shoulder cement spacers. Four different experimental models were prepared. Five different spacers were prepared for each experimental mode and for each joint. We compared four different formulation of cement spacers: spacer #1, in which the spacer was prepared with a premixed bone-cement antibiotic mixture; spacer #2, in which the spacer was prepared by adding antibiotic powder to the bone cement at the time of spacer preparation; spacer #3, in which the spacer was prepared as spacer #2 but was stored for two months before starting the experiment; spacer #4, in addition to the gentamycin, other two antibiotics (tobramycin and vancomycin) were added to the bone cement. Gentamycin concentration was documented at seven intervals of time: T0 = 0h, T1 = 1h, T2 = 24h, T3 = 1W, T4 = 2W, T5 = 1M, T6 = 3M and T7 = 6M. The gentamycin elution at each interval of time was evaluated by using a T-student test. Results. Spacer #2, in which the gentamycin powder was added to the bone cement at the time of spacer preparation showed the higher gentamycin elution at each interval of time observed. In addition, Spacer #1, in which gentamycin powder was premixed with the bone cement showed a higher gentamycin elution when compared with spacer #3, in which the spacers were stored for two months to simulate the preformed spacers. Lastly, the addition of different antibiotic to the bone cement increases the gentamycin elution from the spacers (as demonstrated by spacer #4 model). Conclusions. a higher gentamycin elution was observed if spacer was prepared at the time of surgery when compared with preformed spacer. Lastly, our study confirmed the synergistic effect of adding one or more antibiotics with the aims to increase gentamycin elution

Aim. Due to medical and organizational factors, it occurs in everyday practice that spacers are left in place longer than originally planned during a two-stage prosthesis exchange in the case of prosthetic joint infections. Patients are severely restricted in their mobility and, after initial antibiotic administration, the spacer itself only acts as a foreign body. The aim of this study is to analyze whether the duration of the spacer in situ has an influence on the long-term success of treatment and mortality. Method. We retrospectively studied all 204 two-stage prosthesis replacements of the hip and knee from 2012 to 2016 with a minimum follow-up of two years at an arthroplasty center with 3 main surgeons. The duration of the spacer interval was divided into two groups. Patients replanted within ten weeks (as is standard in multiple algorithms) after systemic antibiotic treatment were assigned to the ‘Regular Spacer Interval (< 70 days)’ group. If the spacer interval was longer, they were assigned to the ‘Long Spacer Interval (≥ 70 days)’ group. Results. Patients were on average 67.69 years old (SD 12.3). The mean duration of the spacer-interval was 100.9 days (range: 423.0; SD, 60.0). In 62 patients reimplantation could be performed within 70 days after explantation, in 142 patients this took longer (max. 438 days). In 26 patients, the spacer had to be changed at least once during this period (11 patients in the hip group, and 15 patients in the knee group). In the remaining cases, other medical or organizational reasons delayed replantation. Both groups were comparable concerning Charlson Comorbity Index, age, number of previous surgeries and laboratory infection markers. There was no statistically significant influence of the duration of the spacer interval on the infection free survival (n=204, p=0.32). There was also no influence on mortality (n=204, p=0.35) and aseptic implant failure (n=204, p=0.15). Conclusions. The timely replantation of a knee or hip prosthesis seems to be reasonable in general because the patients are strongly limited in their mobility and daily activities by the spacer. However, there does not seem to be a negative influence on infection eradication and survival due to a long spacer interval

Aim

Studies have shown that retention of antibiotic cement spacer in selected elderly patients with low functional demand represents a viable option for periprosthetic joint infections (PJI) treatment^1,2.

The aim of this study is to compare the efficacy in infection treating among modular taylored preformed and hand-made antibiotic spacers. Our hypothesis is that modular tailored preformed spacer provides a better rate of infection resolution, better radiological and functional outcomes compared to hand-made spacers.

Introduction. Temporary use of antibiotic-impregnated polymethylmethacrylate (PMMA) bone cement spacers in two-stage revisions is considered to be standard of care for patients with a chronic infection of a joint replacement. Spacers should be wear resistant and load-bearing to avoid prolonged immobilisation of the patient and to reduce morbidity. Most cement spacers contain barium sulphate or zirconium dioxide as radio-opaque substrate. Both are quite hard materials that may negatively influence the wear behaviour of the spacer. Calcium carbonate is another radio-opaque substrate with lower hardness potentially increasing the wear resistance of the spacer materials. The purpose of the study was to compare a prototype PMMA knee spacer (calcium carbonate loaded) with a commercially available spacer (containing barium sulphate) regarding the wear performance and particle release in a knee wear simulator. Material and Methods. Spacer K (TECRES, Italy) was used as barium sulphate (10%) containing spacer material. A prototype material (Heraeaus Medical, Germany) with 15% calcium carbonate was compared. Both were gentamicin impregnated, ready-made for clinical application (preformed) and consist of a tibial and a femoral component. Force-controlled simulation was carried out on an AMTI knee simulator. The test parameters were in accordance to ISO 14243–1 with a 50% reduced axial force (partial weight bearing). Tests were carried out at 37 °C in closed chambers filled with calf serum. Tests were run for 500,000 cycles at a frequency of 1 Hz. For wear analysis, gravimetric wear measurements according to ISO 14243–2 and wear particle analysis according to ASTM F1877–05 were performed. Results. Fig. 1 presents the results of the gravimetric wear measurements. For the Spacer K cement a mean articular wear mass of 375.53±161.22 mg was determined after 500.000 cycles (femoral components: 149.55±17.30 mg, tibial components: 225.98±153.01 mg). The prototype cement showed lower mean total wear of 136.32±37.58 mg (femoral components: 74.32±33.83 mg, tibial components: 61.99±15.74 mg). However, a statistically significant lower wear rate was only seen for the femoral components (p=0,027). In Fig. 2 isolated PMMA wear particles are shown and the morphological characteristics are given in Tab. 1. Discussion and conclusion. The prototype material showed better wear performance in terms of gravimetric wear and particle release. Thus calcium carbonate seems to be a promising material as radio-opaque substrate in PMMA spacers. Nevertheless, the wear amount released from both spacer materials is much higher as compared to conventional total knee replacements with polyethylene inserts. In this context biological reactions against PMMA particles and an increased release of cytokines have been reported in vitro [1] and furthermore, the promotion of osteolysis has been shown in vivo in the presence of PMMA particles [2]. As a clinical consequence we suggest excessive debridement during removal of the cement spacer components to reduce the risk of third body wear for the final joint replacement. Beside the wear performance further studies are essential to prove the mechanical stability and the antibiotic release kinetics for the prototype cement

The use of antibiotic-spacer, it is essential to treat infections in orthopedics. They play a dual role, to fight the infection directly on the outbreak and keep the length or the articulation of the limbs thus facilitating the second operation. To date it is not known, the superiority of use of 3 antibiotics compared to two. Authors try to compare industrial preformed spacers with two antibiotics with custom made spacers with three antibiotics to assess (a) the control of infection, (b) complications, (c) quality of life, (d) pain and (e) patient satisfaction.

137 patients treated at the Institute Codivilla-Putti from January 2010 to December 2012 were considered: 68 patients treated with antibiotic preformed spacer (clindamycin + gentamicin) or (Erythromycin + Colistin), 69 patients treated with antibiotic spacer added with 3 antibiotics (clindamycin + gentamicin + vancomycin) or (Erythromycin Vancomycin + Colistin).

Demographic data were collected:

type and site of infection (classified by Cerny-Mader)

Primary outcome of infection control or relapse after at least 12 months of follow-up were assessed. Complications were recorded. Each patient completed a test on the quality of life and a satisfaction scale self-referenced.

After a mean follow-up of 33.82 months (SD 14:50), at the end of the treatment, at last follow up 15/133 were infected. 4 died from other causes not correlated with infection, whit a 11.3% rate of reinfection.

Up to our knowledge, there is only one study using the procedure in two steps comparing the use of spacers loaded with 2 or 3 antibiotics. Our results show that a revision protocol in two steps with 3 antibiotic loaded spacers have a high success rate in the treatment of chronic osteomyelitis. We can observe that patients treated with custom-made cements are 4 percentage points lower than those treated with preformed cements, but there are no statistically significant differences in the rate of recurrence of infection. Our results suggest that a two stages procedure with three antibiotic loaded spacers should be considered in selected patients to avoid rescue procedures, such as amputation and arthrodesis. We think is important to do more randomized trials, controlled, prospective study with a larger group to detect statistically significant differences.

Aim

To improve the challenging treatment of periprosthetic joint infections (PJI), researchers are constantly developing new handling methods and strategies. In patients with PJI after total knee arthroplasty (TKA) and severe local or systemic comorbidities, a two-stage exchange using a temporary antibiotic loaded PMMA-spacer is considered gold standard. This method has undisputed advantages, however, the increased risk of biofilm formation on the spacer surface, bone defects and soft tissue contractions after a six-week spacer interval are severe limitations. Our hypothesis is that a vacuum sealed foam in combination with constant instillation of an antiseptic fluid can address these drawbacks due to a significantly reduced spacer interval.

Aim

The primary endpoint of this study is to characterize the progression of bone defects at the femoral and tibial side in patients who sustained PJI of the knee that underwent two-stage revision with spacer implantation. In addition, we want to analyze the differences between functional moulded and hand-made spacers.

Aim

The preparation of antibiotic-containing polymethyl methacrylate (PMMA), as spacers generates a high polymerization heat, which may affect their antibiotic activity; it is desirable to use bone cement with a low polymerization heat. Calcium phosphate cement (CPC) does not generate heat on polymerization, and comparative elution testings are reported that vancomycin (VCM)-containing CPC (VCM-CPC) exceeded the antibiotic elution volume and period of PMMA (VCM-PMMA). Although CPC alone is a weak of mechanical property spacer, the double-layered, PMMA-covered CPC spacer has been created and clinically used in our hospital. In this study, we prepared the double-layered spacers: CPC covered with PMMA and we evaluated its elution concentration, antimicrobial activity and antibacterial capability.

Aim

The effectiveness of mandatory joint aspiration prior to re-implantation in patients with a cement spacer already in place is unclear.

The aim of this study was to evaluate the role of culturing articular fluid obtained by joint aspiration prior to re-implantation in patients who underwent a two stage septic revision.

Aim

Septic arthritis of the hip is a rare entity among the adult population, but with a potential severe repercussion. The most accepted treatment is the hip debridement, even though a notorious proportion of the cases need further hip replacement owing to the cartilage destruction. The aim of this study is to analyse all our cases of septic arthritis of the hip treated with a 2-stage strategy using an antibiotic-loaded cement spacer.

Several risk factors can and should be addressed during first stage or spacer implantation surgery in order to minimize complications. Technical aspects as well as practical tips and pearls to overcome common nuisances such as spacer instability or femoral and acetabular bone loss will be discussed and shown with pictures.

Total joint arthroplasty (TJA) is one of the most successful procedures in orthopaedics and excellent results are expected in virtually all cases. Periprosthetic joint infection (PJI) though unusual, is one of the most frequent and challenging complications after TJA. It is the third most common cause of revision in total hip replacement, responsible for up to 15% of all cases.

In the past few years several improvements have been made in the management of an infected total hip prosthesis. Nevertheless it remains a challenging problem for the orthopaedic surgeon. Although numerous studies report favourable outcomes after one-stage revision surgery, two-stage has traditionally been considered as the gold standard for management of chronic infection. Two-stage exchange consists of debridement, resection of infected implants and usually temporary placement of an antibiotic-impregnated cement spacer before reimplantation of a new prosthesis.

Spacers can be classified as static or articulating. The goals of using an articulating antibiotic loaded cement spacer are two-fold: to enhance the clearance of infection by local antibiotic therapy and dead-space management while maintaining joint function during treatment thus improving the functional outcome at reimplantation. Still, hip spacer implantation is not innocuous and there are several possible complications.

Going forward, one must consider not just eradicating infection but also the importance of restoring function. In this regard using a mobile spacer adds an element of physiologic motion that both increases patient comfort between stages and facilitates re-implantation surgery. Conversely, mechanical complications are one of the major consequences of this preference. Be that as it may there are ways to minimize these problems. It is the surgeon responsibility to optimize mechanical circumstances as much as possible.

I would like to thank Dr. Ricardo Sousa for his help with this work

Infection remains a serious complication of total hip replacement (THR). Management options have been developed to improve clearance of infection while maintaining joint function during treatment and improve outcome at reimplantation. The gold standard in management is generally considered to be implant removal and thorough debridement with antibiotic therapy delivered systemically and locally with impregnated spacers. However, some surgeons still prefer to use Girdlestone resection arthroplasty, thus not leaving any foreign body in situ.

The aim of this study was to compare infection clearance rates, radiographic and functional outcomes after two-stage revision of total hip arthroplasty with (1) gentamicin-loaded bone cement spacer or (2) Girdlestone resection arthroplasty as the first stage of treatment.

We retrospectively reviewed data of 48 patients (20 females, 28 males) with implanted spacers and 53 patients (21 females, 32 males) treated with resection arthroplasty at tertiary care university hospital in the years 2008–2012. Minimum follow-up was three years (range, 3–7 years). Treatment choice was at the operating surgeons's discretion.

In the spacer group, mean age at the time of first stage was 62 years (range 24–79 years), time from primary replacement 14 months, and the time from the first to the second stage of the revision 7 months. At latest, minimum 3-year follow-up, two were still ambulating with a spacer in situ, and five were re-revised with another spacer before the reimplantation of the THR.

In the resection arthroplasty group, mean age at the time of first stage was 64 years (range, 37–87 years), time from primary replacement 13 months, and the time from the first to the second stage of revision − 10 months. At the latest follow-up, four patients were ambulating with resection arthroplasty, one did not clear his infection and one died of unrelated causes.

The cure ratio appeared to be the same within both groups (Fisher exact test, p=0.08). Patients with spacers achieved better functional results, used less supports for ambulation and had less leg length discrepancy after the second stage of revision. In the light of those results, we cannot recommend for the use of resection arthroplasty in the treatment of the infected THR.

Purpose

There is a large gap between UKA and TKA in terms of tissue preservation including bone stock and knee ligament. We have recently introduced bicompartmental UKA (Bi-UKA) to fill the gap and achieve more “physiological” knee than TKA. In this study, we report the short-term results of Bi-UKA.

Purpose

Management and outcomes of fungal periprosthetic joint infection (PJI) remain unclear due to its rarity. Although two-stage exchange arthroplasty is considered a treatment of choice for its chronic features, there is no consensus for local use of antifungal agent at the 1st stage surgery. The purpose of this study was to evaluate the efficacy of antifungal-impregnated cement spacer in two-stage exchange arthroplasty against chronic fungal PJIs after total knee arthroplasty (TKA).

Aims

1. A two-stage revision remains as the “gold standard” treatment for chronically infected total knee arthroplaties. 2. Evaluate technical challenges in two stage revision.

BACKGROUND

High-dose antibiotic cement spacers are commonly used to treat prosthetic joint infections following knee arthroplasties. Several clinical studies have shown a high success rate with antibiotic cement spacers, however there is little data on the systemic complications of high-dose antibiotic spacers, particularly acute kidney injury (AKI). This study aims to determine the incidence of AKI and identify risk factors predisposing patients undergoing staged revision arthroplasty with antibiotic cement spacers.

Purpose

Failure resulting from a recurrent infection in total knee arthroplasty (TKA) is a challenging problem. Knee arthrodesis is one treatment option, however fusion is not always successful, as there is huge bone defect. The authors reports a new arthrodesis technique that uses a bundle of flexible intramedullary rods and an antibiotic-loaded cement spacer.

We present a case of multifocal infection involving the left total hip replacement and the right total knee replacement of a patient, further complicated by an infected non-union of a periprosthetic fracture of the right knee. This required the unique simultaneous management of both infection eradication and fracture stabilization in the knee.

Both sites were treated with a 2-stage procedure, including the novel use of a stemmed articulating spacer for the right knee. This spacer was made combining a retrograde humeral nail, coated with antibiotic-impregnated cement, and a pre-formed articulating cement spacer. The patient was able to weight-bear on this spacer. The fracture went on to unite, and a second stage was performed with the use of stemmed prosthesis and augments. She remains infection free 2 years after the second stage operation.

The use of a stemmed articulating knee spacer can facilitate infection eradication and fracture stabilization while preserving some motion and weight-bearing ability in the 2 stage management of an infected periprosthetic fracture of the knee.

INTRO

Two-stage revision arthroplasty for PJI may make use of an antibiotic-loaded cement spacer (ACS), as successful long- term prevention of reinfection have been reported using this technique.[i] However, there is little data on systemic complications of high-dose antibiotic spacers. Acute kidney injury (AKI) is of clinical significance, as the drugs most commonly utilized, vancomycin and aminoglycosides, can be nephrotoxic. We intended to determine the incidence of AKI in patients that underwent staged revision arthroplasty with an ACS, as well as to identify potential predisposing risk factors for the disease.

Introduction

Infection following total joint arthroplasty is a major and devastating complication. After removal of the initial prosthesis, an antibiotic-impregnated cement spacer is inserted for approx. three months. Treatment is completed by a second stage revision arthroplasty.

Up to now, spacers are produced from conventional bone cements that contain abrasive radio-opaque substances like zirconium dioxide or barium sulphate. As long as spacer wear products (cement particles containing these hard substances) are not fully removed during the final revision surgery they may enter the articulating surfaces of the revision implant leading to third body wear.

In order to reduce the formation of reactive wear particles, a special cement (Copal(r) spacem) without abrasive zirconium dioxide or barium sulphate was developed.

To date, no comparative tribological data for cement spacers have been published. Hence, we carried out a study on the wear properties of Copal(r) spacem (with and without gentamicin) in comparison to conventional bone cements (Palacos(r) R and SmartSet(r) GHV).