Polymethylmethacrylate spacers for shoulder periprosthetic infections

Spacers for Life: High Mortality Rate associated with Definitive treatment of shoulder periprosthetic infection with permanent antibiotic spacer

Periprosthetic infections of the shoulder have been treated with a number of different surgical prototocols, including washout with prosthesis retention, washout with partial prosthesis retention, complete prosthesis exchange at a single stage, two stage revision with implant removal and insertion of an antibiotic spacer followed by a delayed prosthesis re-insertion, implant removal and spacer insertion without subsequent revision, and resection arthroplasty. 

These authors reviewed their experience with 17 patients (mean age of  62.4 years (range 50-73); ten female). Revision with pacer placement was performed at a mean 6.1 years (range 0.48 - 14.9 years) following index arthroplasty. These patients had had an average of 2.2 procedures after the index arthroplasty prior to spacer placement.

The most common organisms were Cutibacterium acnes (6), Methicillin sensitive Staphylococcus aureus (MSSA) (6), Methicillin resistant  Staphylococcus aureus (MRSA) (2), coagulase negative Staphylococcus (2), Serratia marcescens (1), gram-positive cocci (1), Enterobacter faecalis (1), Enterobacter cloacae (1), Diphtheroids (1),  and culture negative (1). Eight had a draining sinus, purulence was found at surgery in thirteen cases, ten had elevated sedimentation rates. Five patients had spacer exchange after initial spacer placement.

Apparently the spacers used in these patients were hand crated by the surgeon, either with a stem containing a metal wire to aid in retrieval

or without a stem.

The mortality rate was 9/17 (52.9%). 

Of the 8 surviving patients, the mean ASES score was 33.9 (range 13.3-24 80.0).

Comment: There are two reasons for chronic spacer placement (rather than proceeding with the second stage of a two-stage revision): (1) the patient does not want further surgery (because of acceptable shoulder function or out of fear of further complications) and (2) the surgeon decides that either the patient or the shoulder is not suitable for additional shoulder reconstruction. In addition, as pointed out in this article, some patients expire before a second state could be performed.

As indicated in another article "Prolonged implantation of an antibiotic cement spacer for management of shoulder sepsis in compromised patients" (see this link), patients can have acceptable function with long standing spacer placement. On the other hand, as indicated in this link, spacers can be associated substantial complications.

It is of interest that a commonly used commercially available spacer 

contains Gentamycin, which is not particularly effective against Cutibacterium (the commonest organism found in shoulder periprosthetic infections).

Our primary indications for spacer placement are: (1) presence of a draining sinus, (2) purulence, (3) infection with organisms other than Cutibacterium or coagulase negative Staph, and (4) failed single stage revision.

One of the issues with chronic spacer placement is progressive glenoid erosion as shown in the case below

immediate post operative radiograph

radiograph at one year after spacer implantation

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Here are some videos that are of shoulder interest

Shoulder arthritis - what you need to know (see this link).

How to x-ray the shoulder (see this link).

The total shoulder arthroplasty (see this link).

The ream and run technique is shown in this link.

The cuff tear arthropathy arthroplasty (see this link).

The reverse total shoulder arthroplasty (see this link).

The smooth and move procedure for irreparable rotator cuff tears (see this link).

Shoulder rehabilitation exercises (see this link).

Antibiotic spacer for periprosthetic infection - how long can they be left in?

Antibiotic cement spacer retention for chronic shoulder infection after minimum 2-year follow-up

These authors reviewed the long-term functional and patient-reported outcomes data of 22 patients with retained antibiotic cement spacers. All patients were originally offered a 2-stage revision and declined. Twelve patients had a minimum follow-up of 2 years (average 5.6 years) and were included in their cohort. Mean age was 70.7, 8/12 patients were female, and the average body mass index was 27.8. 

Eight patients had spacer placement for chronic shoulder arthroplasty infections, whereas 4 patients had spacer placement for chronic osteomyelitis of the proximal humerus. 

No patients were currently being treated with suppressive antibiotics. One patient had negative cultures at the time of antibiotic spacer placement. The most common organisms were Cutibacterium (6), Staphylococcus epidermidis (6), and methicillin-resistant Staphylococcus aureus (4), with 4 patients growing more than 1 species.

 

The average ASES score was 54, QuickDASH was 45, and VAS score 2.8. Average active range of motion was 68 of forward elevation and 35 of external rotation.

Three patients required revision of their antibiotic spacer because of continued pain and positive cultures on joint aspiration after completion of antibiotics, resulting in a reoperation rate of 25%.

Comment: A single stage exchange remains our primary approach for shoulder periprosthetic infections from Cutibacterium or Coagulase negative staph. We find spacers particularly helpful (1) in cases where a single stage exchange has failed or in cases with draining sinuses, (2) for infections by organisms other than Cutibacterium or Coagulase negative staph, and (3) for cases of suspected metal allergy . It is important to use a spacer with a metal reinforcement to prevent fracture on removal. It is also important to find the right balancer in stem fixation, so that the spacer is not loose on one hand and can still be removed without damaging the shaft on the other. 

Here are the x-rays of a man with a retained spacer after multiple failed procedures for a Cutibacterium periprosthetic infection.

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Failed total shoulder: infected?

A patient presented to us one year after having had a left total shoulder using this prosthesis.

The patient experienced pain and stiffness since surgery. The patient has also had chronic swelling and a draining sinus. 

The patient had had two limited I&D's by the original surgeon to drain what was thought to be hematoma. All cultures were negative. The patient  was unable to use the arm for daily activities.

The patient had completed IV antibiotic for a short course of 5 days and an oral course of Keflex and doxycyline. At the time of presentation, the arm had the appearance shown below. CBC, sed rate and CRP were all normal.

And this x-ray showing a fractured central metal peg with surrounding osteolysis. 

We revised this prosthesis by removing all components. The retrieved glenoid showed a fractured peg

The portion of the peg remaining in the glenoid had to be removed with a trephine.

Removal of the humeral component was difficult because of the tight diaphysial fit, the proximal ingrowth surface, and the fragile osteopenic metaphyseal bone.

A cement spacer was inserted with a plan 6 weeks of IV Ceftriaxone followed by oral Augmentin. The pathology report from surgery was as follows: 

Left shoulder capsule, excision: - Fibro-connective tissue with focal fibrin deposition, chronic inflammation, giant cell reaction, and rare neutrophils focally present.  Very few (<5/HPF) neutrophils are identified in one focal area directly underlying surface fibrin deposition. On retrospective review of the frozen section slides, these neutrophils are present, but do not reach numbers above 5/HPF.

At the time of the revision, 8 specimens were submitted for culture. The humeral stem had one colony only of coagulase negative Staph (SpCV 0.1), and one of three capsule specimens grew one colony only of Propionibacterium (SpPV 0.1). The rest showed no growth at 3 weeks.

Four months later, we removed the spacer and inserted a reverse total shoulder. In spite of the glenoid bone deficiency, robust fixation of the baseplate was achieved without bone grafting.

 Comment: When a shoulder arthroplasty fails, we consider
(1) removal/revision of loose components
(2) single stage removal/revision of all components
(3) insertion of an antibiotic spacer, possibly as the first step in a two-stage revision
(4) removal of all components without re-insertion

The decision among these options needs to be based on the information available before and at surgery. Often, as shown in this case, the history, the physical examination, and plain radiographs provide most of the needed information. The results of cultures obtained at the time of revision surgery does not become available in time to inform the surgical decision-making.

This case demonstrates (1) the ever present risk of infection in shoulder arthroplasty, (2) the susceptibility of fatigue fracture of a metal post, (3) the problems created by a tight press-fit bone ingrowth stem should prosthesis removal become necessary.

The potential for fatigue fracture of a hybrid post has been shown in a recent article

Five-year minimum clinical and radiographic outcomes of total shoulder arthroplasty using a hybrid glenoid component with a central porous titanium post.

Here is a radiograph from that article.

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The limited effectiveness of Vancomycin-containing spacers in treating periprosthetic infections

Vancomycin-Loaded Polymethylmethacrylate Spacers Fail to Eradicate Periprosthetic Joint Infection in a Clinically Representative Mouse Model

These authors developed a murine model of the first-stage surgery of a 2-stage revision for periprosthetic joint infection involving a 3-dimensionally printed Ti-6Al-4V tibial implant

 infected with Staphylococcus aureus and treated 2 weeks later with irrigation and debridement of the leg with revision of the implant to an articulating vancomycin-loaded PMMA spacer.

Postoperatively, mice underwent radiography and serum inflammatory-marker measurements. Following euthanasia of the mice at 6 weeks, bone and soft tissues were homogenized to quantify bacteria within periprosthetic tissues. Implants and articulating spacers were either sonicated to quantify adherent bacteria or examined under scanning electron microscopy (SEM) to characterize the biofilm.

They found that vancomycin-loaded PMMA spacers eluted vancomycin for 6 days with retained antimicrobial activity.

Control mice had elevated levels of inflammatory markers, radiographic evidence of septic loosening of the implant, and osseous destruction. Mice treated with the vancomycin-loaded PMMA spacer had significantly lower levels of inflammatory markers (p < 0.01), preserved tibial bone, and no intra-articular purulence. 

Retrieved vancomycin-loaded spacers exhibited significantly lower bacterial counts compared with implants (p < 0.001). SEM identified S. aureus encased within biofilm on control implants,

while vancomycin-loaded spacers contained no bacteria.

However, bacterial counts in periprosthetic tissue did not significantly differ between the groups.

The results suggest that the antimicrobial effects of PMMA spacers are tightly confined to the articular space and must be utilized in conjunction with thorough tissue debridement and systemic antibiotics to manage bacteria in the surrounding tissue.

Comment: This article once again demonstrates the remarkable propensity of titanium to enable biofilm formation. It also shows the effectiveness of Vancomycin spacers to resist biofilm formation and to help manage bacteria in the joint. However, it points to the relative ineffectiveness of spacers in managing infection in the tissues surrounding the joint. While they advocate "thorough tissue debridement," it is not always easy to discern what tissue needs to be debrided during surgical management of a periprosthetic infection. Hopefully a combination of debridement and systemic antibiotics will prove effective in managing bacteria in the tissues surrounding an infected prosthesis.

Interested readers may want to read these related posts:

Quantification of Peri-Implant Bacterial Load and in Vivo Biofilm Formation in an Innovative, Clinically Representative Mouse Model of Periprosthetic Joint Infection

Delayed Propionibacterium acnes surgical site infections occur only in the presence of an implant.

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Are antibiotic spacers a benign treatment for shoulder infections?

Complications of antibiotic cement spacers used for shoulder infections

These authors performed a retrospective review of one of two types of commercially available antibiotic spacers implanted in 53 patients (60 spacers) between April 2009 and October 2017 as part of a 2-stage treatment plan.

The 39 infected arthroplasties included 15 anatomic total shoulder arthroplasties, 13 hemiarthroplasties, 10 reverse total shoulder arthroplasties (RTSAs), and 1 cup arthroplasty. The nonarthroplasty shoulder infections included 4 after open reduction and internal fixation of proximal humeral fractures, 3 after rotator cuff repair, 1 after an infected Latarjet procedure, as well as 6 primary shoulder infections without previous surgical procedures. The 14 patients with non-arthroplasty infections had a septic joint with articular destruction and humeral head collapse that precluded any other joint-preservation treatment plan.

All patients were followed up from spacer placement to second-stage revision to shoulder arthroplasty. Ten patients retained the spacers and were followed up for a minimum of 1 year.

No complications were associated with implantation of the spacers. However, of the 44 patients (50 spacers) who underwent a second-stage revision after a mean interval of 6 months (range, 2-18 months), 14 patients had 18 complications.

Fourteen complications occurred between implantation and removal.  The most common complication was bone erosion (6 in the glenoid and 2 in the humeral shaft). 

Other complications were fractures of the spacer (n = 4), spacer rotation (n = 3), and humeral fracture (n = 3). 

 Comment: These authors state that the "infection" diagnosis was based on a combination of symptoms, clinical findings, and laboratory tests. For cases of periprosthetic infection, they used the Musculoskeletal Infection Society criteria (Clin Orthop Relat Res (2011) 469:2992–2994):

However, much of the information needed to use the MSIS criteria to classify a shoulder as being "infected" is not available at the time of the revision arthroplasty. Specifically the results of intraopertive cultures are not available in time to be used to determine the need for a spacer.  Thus, the indications for the use of a spacer are not well defined. 

This paper demonstrates that the use of spacers can be complicated by humeral and glenoid bone loss as well as by humeral and glenoid fracture. The authors also point out that achieving stability of the spacer in the canal can be challenging: insufficient fixation can lead to instability, while the use of cement for fixation can lead to difficulties in the removal of the spacer at the second stage. 

In most cases, our practice is to use a single stage revision without the intermediary of a spacer as our initial procedure in the management of a suspected periprosthetic infection (see this link). This procedure allows augmentation of the humeral bone stock and secure humeral component fixation using impaction allografting and minimizes glenoid erosion by using an implant with a smooth metallic surface rather than the more abrasive surface of a cement spacer. We reserve the use of spacers for failed single stage exchanges or when the presence of a particularly virulent organism (such as MRSA or gram negative rod) is suspected.

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Two stage revision shoulder arthroplasty – how often do we get to stage 2?

A paper entitled "STAGE 1 SHOULDER ARTHROPLASTY: RISK FACTORS FOR REPEAT STAGE 1, SPACER RETENTION AND MORTALITY" was presented at the 2017 open meeting of the American Shoulder and Elbow Surgeons (see this link).

These authors sought to provide the perspective from a national Medicare database on the the outcomes at one year following stage 1 shoulder arthroplasty revision for patients who underwent removal of an infected shoulder prosthesis and placement of an antibiotic spacer.

975 patients who underwent shoulder arthroplasty prosthesis removal and cement spacer placement for infection met all inclusion and exclusion criteria. Within 1 year postoperatively, 21 patients died (2.2%), 70 patients had a repeat stage I procedure (7.2%), 55 patients had a girdlestone-type procedure (5.6%), 349 patients retained their spacers (35.8%) and the remaining 480 patients had a shoulder arthroplasty re-implanted (49.2%)

Independent risk factors for death within 1 year following stage 1 revision included older age, alcohol use, coronary artery disease (CAD) and hemodialysis

Independent risk factors for repeat Stage 1 revision include younger age, morbid obesity, diabetes mellitus and coronary artery disease. 

Independent risk factors for no re-implantation within one year include female gender, older age, tobacco use, alcohol use and inflammatory arthritis.

Only half of patients underwent re-implantation. 

One third of patients retained their spacer and just less than 10% repeated a stage 1 procedure.

Comment: We surely look forward to the publication of the full paper that would include the details of the type of infection and the condition of the shoulder. However, this abstract does indicate that a two stage revision is not always completed, leaving the patient with either a spacer or a resection arthroplasty.


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The reader may also be interested in these posts:

Healing through joint replacement

Supporting progress in shoulder surgery

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What is the significance of positive cultures at re-implantation in a two-stage treatment of a prosthetic joint infection?

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

These authors 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 from 1999 to 2013.

Most spacers contained 3 g of vancomycin and 3 g of tobramycin. At the time of reimplantation, between 3 and 6 samples were obtained for culture.
Among these patients were 267 PJIs (186 knees and 81 hips); 33 (12.4%) had ≥1 positive culture result at re-implantation.

The microorganism isolated at re-implantation was frequently different from that isolated at the time of the initial infection. Furthermore, the organism isolated at the time of subsequent infection was also frequently different from that of the initial infection and the re-implantation.

Treatment failure was defined at a minimum one year follow-up as: (1) failed infection eradication, characterized by a sinus tract, drainage, pain, or infection recurrence caused by the same organism strain; (2) subsequent surgical intervention for infection after reimplantation surgery; or (3) PJI-related mortality.

 The failure rate was
21% for those with negative cultures at re-implantation
50% for those with 1 positive culture at re-implantation and
35% for those with ≥ 2 positive cultures at re-implantation

Comment: This study points out how confusing is the current state of affairs is for diagnosing and managing cases of 'periprosthetic joint infections'.  In this study, when spacers were used at the first stage of a two-stage procedure, cultures were positive at the time of the second stage in over 10% of the cases. The rate of cases meeting a definition of 'failure' was over 20%, even if the cultures were negative at the time of the second stage. Although many authors dismiss a single positive culture as a 'contaminant', one positive culture at the time of re-implantation was associated with the highest rate of failure (50%).  When there was recurrent infection, it was often with different organisms than those cultured at the prior surgery.

It is obvious that we've got a lot to learn. Consistency in culturing practices will do a lot to clarify the situation. We know that the numbers of positive cultures and the types of organisms cultured depend on the number and types of specimens submitted for culture, the media on which they are cultured, and the time these cultures are observed. We also know that recurrence of infection is difficult to define because not infrequently these recurrences are clinically subtle and often become apparent at longer than expected intervals after surgery.

Stay tuned!
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Propionibacterium - the most common bacterium recovered from failed shoulder arthroplasties. Treatment with a spacer.

Definitive Treatment of Infected Shoulder Arthroplasty With a Cement Spacer.

These authors present 9 patients from a single institution who had an infected shoulder arthroplasty. The culture results show that 6 out of the 9 cases were culture positive for Propionibacterium - interestingly one was P. Granulosum rather than P. Acnes. Of the 9 patients in this study, 6 were men. Mean age was 73±9 years. Of the study patients, 1 had diabetes, 2 presented with Parkinson's disease, and 5 had a history of tobacco use. Average body mass index was 27.9±7 kg/m2.

This report describes management with a cement spacer consisting of gentamicin-impregnated polymethyl methacrylate around an AISI 316L stainless steel core. 

All patients had a minimum of 2 years of follow-up.  After mean follow-up of 4 years, none of the patients had clinical or radiographic evidence of infection. Functional outcomes, as measured by American Shoulder and Elbow Surgeons scores, were good or fair in 89% of patients, and the average American Shoulder and Elbow Surgeons score was 57. A review of recent literature suggested that the current findings were similar to those in studies reporting 1- or 2-stage revision procedures. Although cement spacers are typically used as part of a 2-stage revision procedure, the authors suggest that cement spacers can be used effectively to eradicate infection and allow for acceptable functional recovery and range of motion in patients who have severe medical comorbidities and cannot tolerate additional surgery (see the example below of the use of a spacer to manage the infected hemiarthroplasty in an 87 year old man).

Comment: In spite of intense interest in determining the ideal management of failed shoulder arthroplasties with positive cultures for Propionibacterium, the role of single stage prosthesis exchange (see this link), exchange first with a spacer and then a prosthesis at a second stage (two-stage exchange), or, as presented here, a single stage exchange with a spacer. Because of the propensity of this organism to form a biofilm, it is likely that removal of all colonized implants is an important step. Whether it is better to then insert a spacer or a new implant remains unclear. One of the downsides of a 'permanent' space, as the authors of this article point out, is the possibility of glenoid erosion from articulation with the spacer.

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Managing periprosthetic infections: Is there a place for spacers and the two-stage?

The Fate of Spacers in the Treatment of Periprosthetic Joint Infection.

These authors identified 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. 

The mean follow-up duration after initial spacer implantation was 56.2 months. Reimplantation occurred in the joints of 83% of 504 cases. Of these 417 cases, 80% had a minimum one-year follow-up, and 82% of these had successful treatment. The mean duration from resection arthroplasty to reimplantation was 4.2 months (range, 0.7 to 131.7 months). 12% of the 504 joints required interim spacer exchange(s). Of the eighty-seven cases that did not undergo reimplantation, 7% required amputation, 6% underwent a Girdlestone procedure, 5% underwent arthrodesis, and 83% underwent spacer retention. Thirty-six patients died in the interstage period.

Thus of the 504 cases, one out of five did not complete the second stage of the planned two-stage treatment. Of those who did, one out of seven had a subsequent infection.

The authors concluded that 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 did not undergo a subsequent reimplantation for a variety of reasons or required 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.

Comment: This is an article about the use of antibiotic impregnated spacers which, for many, is the preferred method for the management of hip and knee periprosthetic infections. We include it on the shoulder blog because the analysis is compelling and it seems reasonable to believe that the results for the use of spacers in the shoulder would be similar.

The culture results of this study (shown below) are interesting. We can wonder if some of the culture negative joints might have had Propionibacterium that could have been overlooked because the challenging culture approaches for this organism were not in place.

We would like to call attention to related study: Comparison of one and two-stage revision of total hip arthroplasty complicated by infection: a Markov expected-utility decision analysis. These authors reviewed the literature on the treatment of patients with infected total hip arthroplasties and used these data to conduct a Markov cohort simulation decision analysis. They found that the 12 month and the 10 year models favored direct-exchange revision over the two-stage approach, regardless of whether surgeon or patient-derived utilities were used. 

We use a single stage primary exchange to a hemiarthroplasty for cases of suspected periprosthetic shoulder infections, recognizing that the diagnosis of an infection may not be made until week after the procedure. Our approach is described in greater detail here.

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Periprosthetic shoulder infections with Propionibacterium - how many surgeries are needed?

Arthroscopic Tissue Culture for the Evaluation of Periprosthetic Shoulder Infection

The senior authors evaluated approximately 350 painful shoulder arthroplasties performed during the study time period. Of these, 19 patients had undergone culture of arthroscopic biopsy tissue during the evaluation of a possible chronic periprosthetic shoulder infection. None of the patients in the study population had concomitant elevation of the WBC, ESR, and CRP values. The mean age at the time of the index arthroplasty was 56.7 years, and the mean interval (and standard deviation) between the index arthroplasty and the arthroscopic biopsy was 3.0 ± 2.0 years (range, 0.7 to 7.7 years)

Of these 19, 10 had negative arthroscopic biopsy cultures and negative open biopsy cultures taken at the time of surgical revision.

For those shoulders with positive cultures, the mean time for the culture to turn positive was 10.1 ± 3.79 days (range, 5 to 18 days).

7 had positive arthroscopic biopsy cultures for Propionibacterium and positive cultures for this same organism at the time of surgical revision.

2 had positive arthroscopic biopsy cultures for Propionibacterium but no cultures were taken at the time of revision.

6 shoulder joint fluid aspirations were done on patients who were subsequently found to have positive biopsy cultures for Propionibacterium - only one of the aspirates was culture positive.

The authors performed complete removal of the prosthetic components and placement of a custom antibiotic spacer in eight of the nine patients with a positive arthroscopic tissue biopsy culture at a mean of 11.2 ± 8.9 weeks (range, 3.4 to 29.3 weeks). The ninth patient had a single stage revision without apparent recurrence of infection.

Comment: This is a retrospective study of a small percentage of the authors' patients having revision surgery. The authors state that "Arthroscopy was performed in patients for whom the diagnosis of periprosthetic infection could not be reasonably confirmed or refuted by the patient history, physical examination, imaging studies, and laboratory data." One would think that there would be more than 19 of the 350 painful arthroplasties that met these criteria. The case the authors show in figure one is a common scenario: A patient with two years of pain and stiffness after a left TSA. Laboratory results were normal, and there was no growth from a fluoroscopically guided glenohumeral aspiration. An anteroposterior radiograph showed notable radiolucency about the pegged glenoid component". As prior recent posts have pointed out, glenoid or humeral component loosening is strongly suggestive of the presence of Propionibacterium. Again, since glenoid component loosening is a primary cause of failure of total shoulder arthroplasty, one might expect more cases like that shown in figure 1 among the 350. 

It is of interest that the time between between the index arthroplasty and the diagnosis of positive cultures was long:  3.0 ± 2.0 years (range, 0.7 to 7.7 years). This is consistent with the results discussed in a prior post.

Perhaps a bigger question is the protocol to be used in evaluating shoulders for possible Propionibacterium and for treating shoulders with positive cultures. The protocol one might conclude from this paper is that, since as their data show, the presence of Propionibacterium is not at all excluded by the absence of clinical and laboratory evidence of infection, all revisions should be preceded by an arthroscopic biopsy under anesthesia. If the culture results are negative, then a single stage revision is performed. If the culture results are positive a two stage revision is performed. This means that revision of a failed shoulder arthroplasty would commonly require two or three surgical procedures. 

By contrast in our practice (as summarized here), we try to reduce the number of anesthetics to one by obtaining cultures at the time of the revision, performing a single stage prosthesis revision to an uncemented Vancomycin-impregnated impaction grafted hemiarthroplasty followed by systemic antibiotic treatment until the culture results are finalized (at which time the antibiotic program is modified by our infectious disease consultations). We have yet to find convincing data to support the routine use of cement spacers in the management of Propionibacterium-positive failed arthroplasties.

Finally, as shown in this paper, culture of needle aspirated joint fluid is helpful only if the culture is positive, but not it it's negative.

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You may be interested in some of our most visited web pages including:shoulder arthritis, total shoulder, ream and run, reverse total shoulder, CTA arthroplasty, and rotator cuff surgery as well as the 'ream and run essentials'