One-stage Exchange
T. Gehrke
1, S.J. Breusch
21Depatment of Orthopaedics, ENDO-Clinic, Hamburg, Germany
2Depatment of Orthopaedics, University of Edinburgh, United Kingdom
Introduction
The management of periprosthetic infection remains a challenge to any arthroplasty surgeon. Several treatment options are available depending on the clinical situation, the local set-up, the surgeon’s preference and expertise. In the most frequent sce- nario, where revision surgery with prosthesis exchange is necessary, controversy still exists between single and two-stage approach to the problem. With the introduction of articulating spacers, the functional outcome of two-stage exchange has signifi- cantly improved [8, 19, 26, 36]. However, one-stage exchange offers certain advan- tages including the need for only one operation (if no recurrence), shorter hospitali- sation, lower overall cost and high patient satisfaction [3, 10, 11]. In this review the authors will describe their management strategy and experience with direct exchange. Particular emphasis is given to the requirements that provide the basis for success. Furthermore, 8 year outcome data of 100 consecutive patients following one- stage revision TKA for infection with no lost to follow-up are provided and discussed.
Pathophysiology and Etiology
Periprosthetic infection is a foreign body associated infection. It must be clearly dif-
ferentiated from other bone infections, like osteomyelitis. Not only bacteria are rec-
ognized by the host defense as “enemies”, but also foreign bodies. Both, micro-organ-
isms and foreign materials induce inflammation as a reaction to tissue injury and are
handled in the same manner by the human body. More than 90 % of infections during
the first year after implantation are due to bacterial contamination during surgery
[30]. Hematogenous infections and infections which reach the site of infection from
other sources are less frequent. In the presence of foreign bodies, a contamination as
low as 100 colony-forming units (CFU) is sufficient to induce an infection in contrast
to 10,000 cfu without foreign material [6, 31]. This effect is due to the diminished
clearing capacity of phagocytosis by leukocytes in the presence of foreign material
[44]. Macrophages as the first line of defence try to degrade these materials by enzy-
matic digestion. But if the foreign body is too large for our little macrophage, fibro-
blasts are stimulated to form granulation tissue around the foreign body. Just like
fibroblasts, a number of bacteria, in particular staphylococci are able to colonize the
surface of the foreign body. The competition between the fibroblasts, activated by the
macrophages, and the bacteria to colonize the foreign body has been given a very descriptive term by Gristina: “The race for the surface”. The bacteria are anchored to the surface by forming a biofilm. This biofilm protects from the host’s defence mecha- nisms and these sessile bacteria are also highly resistant to antimicrobial agents [5, 18, 44]. But colonization and formation of slime alone do not cause an infection or an infectious disease. Periprosthetic infection begins when some of the sessile bacteria switch back to planktonic forms and induce infection in the adjacent tissue – peri- prosthetic osteomyelitis [11]. The period between colonization and clinically detect- able infection may last for months, even up to about three years. Signs of infection may occur very late when the bacteria leave the interface, invade surrounding tissue and induce a secondary osteomyelitis. It is important to realise that periprosthetic infection is not only an infection of the prosthetic interface, but also an infection of bone and surrounding soft tissues. This understanding is of utmost importance for the surgical management.
Diagnosis
The diagnosis of periprosthetic infection can be simple, but occasionally most diffi- cult to establish. In the case of immediate postoperative infection the first symptoms can be seen around day 4 to 8 after TKA. If purulent secretion is present the diagnosis is obvious. However, prolonged wound discharge (
87 – 10 days), continued soft tis- sue swelling and induration, or wound dehiscence should be taken seriously, consid- ered as infection until proven otherwise and managed with a pro-active and aggres- sive attitude. If an early infection (within 3 weeks) occurs after patient discharge from hospital, often superficial wound healing problems, hematomas and seromas are evi- dent. However, this is not always obvious and the clinical signs can be more subtle.
Monitoring of C-reactive protein (CRP) is probably the most useful parameter in this scenario. CRP values are highest with a peak on day 2 – 3 postop, and should return to normal, preoperative values within 3 weeks. In some patients CRP normalisation can take up to 6 weeks and there is no reason for concern or panic, as long as CRP values show a continuing decline. Failure to do so should result in prompt action. In our experience patients with good (non-indurated) soft tissues, dry wounds and CRP lev- els below 60 to 90 mg/dl on day 5 – 6 can be considered “safe”, but all others (or if in doubt) warrant early follow-up in order not to miss the window of opportunity for early aggressive debridement and suction/irrigation [38].
Whereas clinical symptoms are the main parameters for diagnosing periprosthetic infection in its early stages, laboratory and radiological investigations become more important in late infection. Erythrocyte sedimentation rate has a longer lag time than CRP and is probably only a useful additional tool in the management of patients with rheumatoid arthritis with chronically raised CRP (and ESR) levels. ESR and CRP have a specificity and sensitivity of about 90 %. In contrast, leukocytosis is unspecific and rarely present. Other more sophisticated parameters like Interleukin 6, Procalcitonin or the Interleukin 2 receptor are expensive and generally give us no additional clini- cally relevant information.
The most important clinical parameter in late infection is the presence (or recur-
rence !) of pain. Although rarely described in the literature local skin and deep soft
tissue induration are poor prognostic indicators in our experience. A “woody” leg should raise the level of suspicion ! Serial radiographic comparison can be of value and bone scans are non-specific although highly sensitive. Bone scans can stay hot for several years following arthroplasty, can represent bone remodeling and may be mis- leading. Recently, antigranulocyte scintigraphy was reported with a sensitivity of 1.0, a specificity of 0.83, a positive prediction value of 0.83 and a negative prediction value of 1.0. In contrast, preoperative joint aspiration and culture, was less sensitive, but showed a specificity and positive prediction value of 1.0 [28].
In our own practice joint aspiration with prolonged culture time of at least 10 – 14 days is considered mandatory and gold standard. This must be done under strictly sterile conditions without the use of local anaesthetic and saline, which both can exhibit bactericidal effects. The accuracy of aspiration in the Endoclinic in Hamburg has been higher than 95 % [40] in more than 7500 periprosthetic infections treated.
However, some special aspects in the investigation of the aspirated fluid have to be considered. The number of bacteria is very small so culture must last for a minimum of 10 – 14 days and not only 3 days as is usual for blood cultures. Fast transport of the aspirated fluid in a sterile container – swabs are inadequate – to the laboratory, rapid processing and an experienced microbiologist with an interest in this demanding problem are important pre-requisites and of utmost importance for success. In some cases repeated aspiration can increase the capture rate, particularly if the patients have been treated with antibiotics previously. A minimum period of 14 days off any antibiotics is required before aspiration in this instance.
Management Strategy – One Stage Exchange
Only in the presence of a positive culture and with the respective antibiogram at hand should a one-stage procedure be considered and offered to the patient. A cemented fixation using antibiotic loaded acrylic cement (ALAC) is considered treatment of choice to achieve high local therapeutic levels of antibiotic elution from ALAC [12].
The secret of success not only depends on complete removal of all foreign material (including intramedullary cement and restrictors) and the use of ALAC, but in partic- ular on the aggressive and complete debridement of the soft tissues and bone. A full synovectomy also in the posterior aspects of the knee is considered of importance and performed routinely. To gain access this invariably means sacrificing the poste- rior cruciate ligament, if still existing, and not infrequently the collateral ligaments, which will result in the need for hinged implants (see below).
The ALAC should be regarded as a means to prevent re-colonization of the new
implants and not seen as the “killer” and cure for infection. It is the surgeon’s knife
above all, which will determine success. Surgery in periprosthetic infection should be
carried out as a tumor procedure and no comprise should be made during debride-
ment: if in doubt cut it out !
General Pre-Operative Planning Anaesthesia:
)
Clinical and anaesthesiological assessment of operative risk
)Adequate quantity of additional donor blood
)
In case of long exchange operations preoperative administration of fibrinolysis inhibitors (e.g. Trasilol®) is recommended. Cave: risk of anaphylactic shock!
Radiological Preparation
)
Conventional x-rays in two or three planes (patella skyline) in a standardized position are usually adequate. Imaging of hips and entire femur if ipsilateral hip replacement. Long leg alignment films are recommended.
)
In some cases calibrated x-rays may have to be taken with a radiopaque scale, especially when special, extra small, custom-made implants or megaprostheses (e.g. total femoral replacement) are required.
Patient Information – Specific Risks
)
Risk of recurrent or new infection – about 10 – 15 %
)
Re-operation for haematoma, wound debridement or persistent infection
)Damage to peroneal nerve or main vessels
)
Postoperative stiffness and loss of function (extensor mechanism)
)Risk of intra- and postoperative fracture
)
Increased risk of aseptic loosening
Surgeon’s Planning and Preparation Choice of Implants and Cement:
)
The surgeon should have knowledge of the implant in situ and be familiar with its removal and disassembly (e.g. hinge mechanism). Occasionally it is useful to order and use the implant-specific instrumentation, if available for the particu- lar implant
)
A variety of implants must be at hand, ranging from primary total condylar to stemmed hinges, depending on the requirements for reconstruction.
)
Ligament deficient knees will require constraint implants, but ligament defi- ciency may also result during intraoperative debridement – hence the need for rotating of fixed hinge implants. Due to the aggressive soft tissue debridement
strategy of both authors this is the case in almost all cases of one stage exchange.)
Loss of bone stock, the possibility of intraoperative complications such as shaft fractures, perforations of the cortex, windows and tibial/femoral disintegration must be taken into consideration when choosing the implant. Always have a second line of defence available!
)
Distal femoral or proximal tibial replacement implants may have to be chosen in
patients with significant bone deficiency. Bone loss is always significantly more
extensive than radiographically evident. Custom made implants with extra long
Table 1. Combinations of antibiotics recom- mended for addition to PMMA cement.
(Selected according to the susceptibility of the pathogen)
Bacteria Antibiotics Dosage per40 g
PMMA cement Gram positive
Staphylococci Streptococci Propionibacteria
Lincomycin Gentamicin
3.0 g 1.0 g
Staphylococci Streptococci Propionibacteria
Cefuroxim Gentamicin
3.0 g 1.0 g
Staphylococci (highly resistant)
Vancomycin Ofloxacin
2.0 g 1.0 g
Enterococci Vancomycin
Ampicillin 2.0 g
1.5 g Gram negative
Enterobacteriaceae Cefotaxim Gentamicin
3.0 g 1.0 g Pseudomonas aeruginosa Cefoperazon
Amikacin
2.0 g 2.0 g Acid-fast rods
Mycobacteria Streptomycin 2.0 g
or narrow stems may have to be ordered prior to surgery. The potential need for total femoral replacement implants should also be considered.
)
In patients where significant damage to the extensor mechanism is pre-existing or can be anticipated an arthrodesis nail should be available as a last resort (patient consent!)
)
ALAC with additional antibiotics (AB) in powderform to be added intraoperati- vely should be available (Table 1). Invariably at least 2 – 3 mixes of cement (80 – 120 g) per femur and also per tibia are required. Large mixing systems and appropriate cement guns are required. In patients with a narrow diaphysis extra narrow nozzles allow for appropriate retrograde cementing technique.
)
The surgeon should know which type of ALAC was been used at the index opera- tion, as resistance of the organism to the previously used AB must be expected [34, 42] and a different ALAC should be chosen. In individual cases an industrially pre-manufactured ALAC cement may be appropriate. The antibiogram and ideally a recommendation from the microbiologist should be available (Table 1) including the AB for cement impregnation and for postoperative i.v. administration.
Operative steps
Skin Incision and Debridement:
)
Old scars in the line of the skin incision should be excised (Fig. 1).
)
If a prior incision does not lie in this line, keep sufficient distance between it and the new incision. Use the incision from the last approach if technically feasible.
Avoid raising a subcutaneous flap.
)
Crossing the old scar at an acute angle or deviating from it should be avoided.
Fig. 1. Skin incision and fistulectomy
Fig. 2. Complete synov- ectomy and debride- ment
)
Fistulae should be integrated into the skin incision if possible and radically excised all the way to the joint (Fig. 1). If the fistulae lie too far laterally or poste- riorly they are handled by means of a separate excision, following down the fis- tula tract. Methylene blue staining can be helpful in this case.
)
If the need for muscular-cutaneous flaps can be anticipated, a plastic surgeon should be available. However, if the surgeon is familiar with a medial gastrocne- mius transfer, most situations can be handled.
)
As the operative time commonly exceeds 2 hours an above knee tourniquet is
applied but not inflated. The procedure is started without tourniquet so that all
bleeders can be coagulated on the way in. Furthermore, without tourniquet the
boundary between infected tissue, scar and healthy bleeding soft tissue (and bone)
can be distinguished better during debridement. All non bleeding tissue and bone
should be excised. Particular emphasis should be given to perform a complete syn-
ovectomy and debridement in the posterior compartment (Figs 2 and 3).
Fig. 3. Removed sino- via and debrided tissue
Fig. 4. Prosthesis removal may require a dedicated instrumen- tarium
)
Biopsy material, preferably 5 – 6 samples, should be taken as a routine measure from all relevant areas of the operation site for microbiological and histological evaluation [1, 39]. Then the chosen i.v. AB are administered. This commonly comprises a broad spectrum cephalosporin and additionally one or two others according to the antibiogram.
Implant Removal and Completion of Debridement
)
Removing cemented implants stems is generally much easier and less invasive than removing cementless components, in particular when these are stemmed and ingrown.
)
In cases of well fixed uncemented components with stem, often cortical windows are required to gain access to the interface. High speed burrs and curved saw blades aid removal (Fig. 4). Unfortunately even in experienced hands occasion- ally significant destruction and loss of bone stock will occur.
)
Using narrow straight osteotomes with asymmetrically honed blade remove all
Fig. 5. Implant and cement removal with osteotomes
accessible bone cement (if cemented implant), that can be removed without caus- ing further loss of bone stock
)
A Gigli say can be useful to cut around the femoral shield and the tibial base plate of the implant. A full range of narrow and wide osteotomes of various thicknesses (Lambotte osteomes) should be available. By using multiple osteoto- mes, which are carefully driven between tibial base plate and cement from medial and lateral the tibial component, even if stemmed, can be gradually wedged/forced out from its cement mantle (Fig. 5). This is less destructive than aggressive extraction with hammer blows.
)
Extract the implant using special or universal extraction instruments, if avail- able. Otherwise punches are required.
)
Cement removal is completed using special cement chisels, long rongeurs, curret- ting instruments, long drills and cement taps, as well as ball headed reamers. The particular technique of cement removal has been described elsewhere [13, 14].
)
Final debridement of bone and posterior soft tissues must be as radical as possible. It should include areas of osteolysis and non-viable bone (Fig. 6).
)
Copious pulsatile lavage should be used throughout the procedure.
)
After another thorough lavage the intramedullary canals are packed with Chlor- hexidine soaked swabs (Lavasept®) and large Chlorhexidine soaked packs are placed, before the wound is covered with a clean incisional film or closed tempo- rarily.
)
The entire surgical team should now re-scrub and new instruments are used for re-implantation after re-draping.
)
A second dose of i.v. AB is given after 1.5 hrs operating time or if blood loss at this point exceeds 1 l.
Reimplantation
)
After completion of debridement and implant removal, it can be helpful to then
inflate the tourniquet to aid final intramedullary cement removal and in particu-
lar for re-cementation and closure. In short legs or if proximal soft tissue expo-
Fig. 6. Radical soft tissues and bone debridement
Fig. 7. Bone defect reconstruction and prosthesis fixation with antibiotic-loaded acrylic cement
sure is extensive no tourniquet can be used, unless a sterile one can be made avail- able.
)
Reconstruction of bone stock may require the use of allograft, although ideally this should be avoided. We prefer to fill large defects with ALAC if biomechani- cally acceptable (Fig. 7).
)
If morcellized allograft is used, it should be thoroughly lavaged (pulsatile lavage with hot saline !) and impregnated with antibiotics [22] prior to impaction grafting
)
Antibiotic loaded cement is prepared. It is mandatory to only use suitable antibi- otics which need to fulfill the following criteria:
– Appropriate AB, antibiogram, good elution characteristics from cement [43].
– Bactericidal (exception Clindamyin)
– Powder form (never use liquid AB !)
Fig. 8. Post-operative X-rays. One-stage revision with antibiotic-loaded hinged prosthesis
– Pharmaceutical admixing of AB powder to PMMA powder using a fine sieve before mixing
– Maximum addition of 10 %/PMMA powder (e.g. 4 g AB/ 40g PMMA powder – in MRSA: Vancomycin plus Ofloxacin [29].
Cave: Some antibiotics (e.g. vancomycin) will change the polymerization behav-
ior of the cement causing acceleration of cement curing !
)
The principle of modern cementing techniques should be applied. As mentioned above a better cement bone interface can be achieved if the tourniquet is inflated prior to cementing (Fig 8).
)
Postoperatively, i.v. AB are administered according to the treatment recommen- dations given by the microbiologist. Commonly not more than 14 days are required. The value of prolonged AB given orally thereafter is not proven.
)
Serial CRP levels are the most important tool for postoperative monitoring.
Discussion
One stage exchange for infected TKA is less popular than two stage procedures [22].
Higher success rates for two stage have been postulated and with articulating spacers the functional outcome and patient satisfaction [17, 32] have improved significantly [8, 19, 26, 36]. Furthermore, the operative approach is less demanding due to minimal contractures [7, 9, 17, 25] and the rate of extensor mechanism complications has been reduced [19, 27]. Far more studies have been published about two stage revision and fewer series, usually with small patient numbers treated with one stage exchange are available.
In the non-English literature, the early Endoclinic experience from 1976 to 1985, including 118 one stage revision TKAs for infection – followed for 5 – 15 years – showed a 73 % chance of cure of infection [10]. An English literature review in 2002 of direct exchange [38] revealed that there were only 8 studies on this topic reporting a total of 37 knees – 32 treated with ALAC -, of which 18 were part of one series [15].
All other quoted studies reported patient numbers below 6 and therefore should be considered case reports [38]. The overall success rate, i.e. control of infection was cal- culated as 89.2 %, but no information was provided regarding the respective length of follow-up. The largest cohort of 69 patients was excluded from the metaanalysis as no distinction from two stage outcomes was possible [38].
A more recent study [4] of 22 consecutive patients treated with direct exchange, radical debridement, ALAC, i.v. AB for 4 – 6 weeks followed by 6 – 12 months oral AB showed a 90.9 % rate free of infection after 1.4 to 19.6 years (mean 10.2 years). The authors concluded that their results compare favorably with delayed exchange revi- sion TKA.
Apart from use of ALAC [21, 38] aggressive debridement of all infected tissue [3, 15, 38] the absence of sinus formation [38] and Gram-positive organisms [38] are considered factors associated with success. Our results and experience would support that Gram-positive organisms are more benign, but fistulae have not been associated with poorer outcome. On the contrary, if sinus formation is present (i.e. draining infection) the extent of soft tissue infection is usually less pronounced. Multiple pre- vious surgeries have been reported to adversely affect the chance of success [23]. This, however, was not the case in our series.
The duration of postoperative intravenous antibiotics ranged from 2 – 4 weeks (mean 2.4) in the metaanalysis of direct exchange [38]. A prolonged administration of intravenous AB for 6 weeks is particular common in the interval between first and second stage [16]. However, the rationale for this has been questioned most recently [24] and the authors concluded from their experience in 38 patients, that a prolonged course of AB does not seem to alter the incidence of recurrent or persistent infection after two stage revision. Interestingly, if patients are re-aspirated prior to re-implan- tation positive cultures can be found in almost 10 %, thus providing the rationale and justification for pre-revision cultures [33]. In the Endoclinic protocol of direct exchange a duration of 10 days is rarely exceeded now.
In our series of 100 consecutive patients with infected TKA, which were treated
with one stage exchange, all required hinge prostheses. This fact both reflects the
degree of aggressive debridement and the patient material. Furthermore, at the time
the use of fixed hinges was policy, but since then the majority of patients are treated
with rotating hinges (ratio 70:30). In a recent report using the same implant for sal- vage revision TKA, 23 cases were done for infection, which showed encouraging out- come at midterm, however inferior compared to aseptic patients [37]. A similar expe- rience with this implant used for salvage of limb threatening cases has also been reported [41]. The functional outcome with this design has been encouraging, although in general stiffer knees have to be expected in septic two stage exchange compared to aseptic revision TKA [2]. In our series there was a 3 % amputation rate, this has dropped , however since to 0.5 % in the last 7 years.
The overall rate of patients free of infection at 8.5 years was 90 % in this consecu- tive Endoclinic series and can be regarded as more than acceptable. If one includes the 3 patients who required a “second-stage” (further direct exchange) then the suc- cess rate is 93 %. Long-term observation is important, as the implant survival rates can deteriorate significantly over time, for both mechanical failure, but also recurrent infection requiring re-operation. In a series of 96 knees, followed for a mean of 7.2 years after two stage revision TKA, the survivorship free of implant removal for re- infection was 93.5 % at 5 years, but dropped to 85 % at 10 years [20].
In conclusion, the Endoclinic results presented here further support the philoso- phy of direct exchange for infected TKA. Patient satisfaction is high as hospitalisation is rarely over 2 weeks and only one operative procedure is required in 90 % of cases.
Decreased morbidity for the patient by eliminating the need for a second major pro- cedure with high risk of repeated blood transfusion [35] and associated prolonged inpatient stay are further arguments in favor of a one stage strategy [3]. It remains the more cost-effective approach [4] and can offer similar if not better cure and survival rates even in the longer term.
References
1. Atkins BL, Bowler IC (1998) The diagnosis of large joint sepsis. J Hosp Infect 40(4):263 – 274 2. Barrack RL, Lyons TR, Ingraham RQ et al (2000) The use of a modular rotating hinge compo-
nent in salvage revision total knee arthroplasty. J Arthroplasty 15(7):858 – 866
3. Buechel FF (2004) The infected total knee arthroplasty: just when you thought it was over.
J Arthroplasty 19(4 Suppl 1):51 – 55
4. Buechel FF, Femino FP, D’ ´Alessio J (2004) Primary exchange revision arthroplasty for infected total knee replacement: a long term study. Am J Orthop 33(4):190 – 198
5. Costerton JW, Stewart PS, Greenberg EP (1999) Bacterial biofilm: a common cause of persis- tent infections. Science 284(5418):1918 – 1322. Review
6. Elek SD, Conen PE (1957) The Virulence of Staphylococcus pyogenes for man: a study of the problems of wound Infection. Br J Exp Pathol 38(6):573 – 586
7. Durbhakula SM, Czajka J, Fuchs MD et al (2004) Antibiotic loaded articulating cement spacer in the 2-stage exchange of infected total knee arthroplasty. J Arthroplasty 19(6):
768 – 774
8. Evans RP (2004) Successful treatment of total hip and knee infection with articulating antibi- otic components: a modified treatment method. Clin Orthop Relat Res (427):37 – 46 9. Fehring TK, Odum S, Calton TF et al (2000) Articulating versus static spacers in revision total
knee arthroplasty for sepsis. The Ranawat Award. Clin Orthop Relat Res (380):9 – 16 10. Foerster v. G, Klueber GD, Kaebler U (1995) Mittel – bis langfristige Ergebnisse nach Behand-
lung von 118 periprothetischen Infektionen nach Kniegelenkersatz durch einzeitige Aus- tauschoperationen. Der Unfallchirurg, 225:146 – 157
11. Frommelt L (2000) Periprosthetic infection – Bacteria and the interface between prosthesis and bone. In: Learmonth ID (ed). Interfaces in total hip arthroplasties. Springer, London.
pp. 153 – 161
12. Gehrke T, Frommelt L, v. Foerster G (1998) Pharmacokinetic study of a gentamycin/clinda- mycin bone cement used in one stage revision arthroplasty
13. In Walenkamp GH, Murray DW (eds): Bone cement and cementing technique. Springer, 1998 14. Gehrke T (2004) Behandlung infizierter Hüft- und Kniegelenksendoprothesen. In Schnettler R, Steinau, HU (eds): Septische Knochenchirurgie, Georg Thieme Verlag, Stuttgart New York: 224 – 57:2004
15. Gehrke T (2005) Revision is not difficult. In Breusch SJ, Malchau H (Eds). The well cemented total hip arthroplasty. Chapter 18, Springer Verlag, Heidelberg, New York, Tokyo, 2005 16. Goksan SB, Freeman MA (1992) One-stage reimplantation for infected total knee arthro-
plasty. J Bone Joint Surg Br 74(1):78 – 82
17. Goldman RT, Scuderi GR, Insall JN (1996) 2-stage reimplantation for infected total knee replacement. Clin Orthop Relat Res (331):118 – 124
18. Goldstein WM, Kopplin M, Wall R et al (2001) Temporary articulating methymethacrylate antibiotic spacer (TAMMAS). A new method of intraoperative manufacturing of a custom articulating spacer. J Bone Joint Surg (Am) 83(Suppl 2 Pt 2):92 – 97
19. Gristina AD (1987) Biomaterial-centred infection: microbial adhesion versus tissue integra- tion. Science 237:1588 – 1595
20. Haddad FS, Masri BA, Campbell D et al (2000) The PROSTALAC functional spacer in two- stage revision for infected knee replacements. Prosthesis of antibiotic acrylic cement. J Bone Joint Surg (Br) 82(6):807 – 812
21. Haleem AA, Berry DJ, Hanssen AD (2004) Mid-term to long term follow up of two-stage reimplantation for infected total knee arthroplasty. Clin Orthop Relat Res (428):35 – 39 22. Hanssen AD, Rand JA, Osmon DR (1994) Treatment of the infected total knee arthroplasty
with insertion of another prosthesis. The effect of antibiotic-impregnated bone cement. Clin Orthop Relat Res (309):44 – 55
23. Hanssen AD (2002) Managing the infected knee: as good as it gets. J Arthroplasty 17(4 Suppl 1):98 – 101
24. Hirakawa K, Stulberg BN, Wilde AH et al (1998) Results of 2-stage reimplantation for infected total knee arthroplasty. J Arthroplasty 13(1):22 – 28
25. Hoad-Reddick DA, Evans CR, Norman P et al (2005) Is there a role for extended antibiotic therapy in a two-stage revision of the infected knee arthroplasty? J Bone Joint Surg (Br) 87(2):171 – 174
26. Hofmann AA, Kane KR, Tkach TK et al (1995) Treatment of infected total knee arthroplasty using an articulating spacer. Clin Orthop Relat Res (321):45 – 54
27. Hofmann AA, Goldberg T, Tanner AM et al (2005) Treatment of infected total knee arthro- plasty using an articulating spacer: 2- to 12-year experience. Clin Orthop Relat Res (430):125 – 131
28. Insall JN, Thompson FM, Brause BD (1983) Two-stage reimplantation for the salvage of infected total knee arthroplasty. J Bone Joint Surg (Am) 65():1087 – 1098
29. Kordelle J, Klett R, Stahl U et al (2004) Infection diagnosis after knee-TEP-implantation. Z Orthop 142(3):337 – 343
30. Kordelle J, Frommelt L, Kluber D et al (2000) Results of one stage endoprosthesis revision in periprosthetic infection caused by methicillin-resistant Staphylococcus aureus. Z Orthop 138(3):240 – 244
31. Lidwell OM, Lowbury EJL, Whyte W et al (1982) Effect of ultraclean air in operating rooms on deep sepsis in the joint after total hip or knee replacement: a randomised study. Br Med J (Clin Res Ed) 285(6334):10 – 14
32. Mangram AJ, Horan TC, Pearson ML et al (1999) The Hospital Infection Control Practices Advisory Committee. Guidelines for prevention of surgical site infection. Infect Control Hosp Epidemiol 20:247 – 280
33. Meek RM, Dunlop D, Garbuz DS et al (2004) Patient satisfaction and functional status after aseptic versus septic revision total knee arthroplasty using the PROSTALAC articulating spacer. J. Arthroplasty 19(7):874 – 879
34. Mont MA, Waldman BJ, Hungerford DS (2000) Evaluation of preoperative cultures before second stage reimplantation of a total knee prosthesis complicated by infection. A compari- son-group study. J Bone Joint Surg (Am) 82(11):1552 – 1557
35. Neut D, van de Belt H, Stokroos I et al (2001) Biomaterial-associated infection of gentamicin-
loaded PMMA beads in orthopaedic revision surgery. J Antimicrob Chemother 47(6):
885 – 891
36. Pagnano M, Cushner FD, Hansen A et al (2004) Blood management in two-stage revision knee arthroplasty for deep prosthetic infection. Clin Orthop Relat Res (367):238 – 242 37. Pietsch M, Wenisch C, Traussnig S et al (2003) Temporary articulating spacer with antibiotic-
impregnated cement for an infected knee endoprosthesis. Orthopade 32(6):490 – 497 38. Pradhan NR, Bale L, Kay P et al (2004) Salvage revision total knee replacement using the
Endo-model rotating hinge prosthesis. Knee 11(6):469 – 473
39. Silva M, Tharani R, Schmalzried TP (2002) Results of direct exchange or debridement of the infected total knee arthroplasty. Clin Orthop. Relat Res (404):125 – 131
40. Spanghel MJ, Masri BA, O’Connell JX et al (1999) Prospective analysis of preoperative and intraoperative investigations for the diagnosis of infection at the sites of two hundred and two revision total hip arthroplasties. J Bone Joint Surg (Am) 81(5):672 – 683
41. Steinbrink K, Frommelt L (2005) Treatment of periprosthetic infection of the hip using one stage exchange surgery. Orthopade 24(4):335 – 343
42. Utting MR, Newman JH (2004) Customised hinged knee replacements as a salvage procedure for failed total knee arthroplasty. Knee 11(6):475 – 479
43. van de Belt H, Neut D, Schenk W et al (2001) Staphylococcus aureus biofilm formation on different gentamicin-loaded polymethylmethacrylate bone cements. Biomaterials 22(12):
1607 – 1611
44. Walenkamp G (2001) Gentamicin PMMA beads and other local antibiotic carriers in two- stage revision of total knee infection: a review. J Chemother 13 Spec No 1(1):66 – 72 45. Zimmerli W, Lew PD, Waldvogel FA (1984) Pathogenesis of foreign body infection – evidence
for a local granulocyte defect. J Clin Invest 73(4):1191 – 1200
