Document Detail

Early migration of tibial components is associated with late revision: a systematic review and meta-analysis of 21,000 knee arthroplasties.
Jump to Full Text
MedLine Citation:
PMID:  23140091     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
PURPOSE: We performed two parallel systematic reviews and meta-analyses to determine the association between early migration of tibial components and late aseptic revision.
METHODS: One review comprised early migration data from radiostereometric analysis (RSA) studies, while the other focused on revision rates for aseptic loosening from long-term survival studies. Thresholds for acceptable and unacceptable migration were determined according to that of several national joint registries: < 5% revision at 10 years.
RESULTS: Following an elaborate literature search, 50 studies (involving 847 total knee prostheses (TKPs)) were included in the RSA review and 56 studies (20,599 TKPs) were included in the survival review. The results showed that for every mm increase in migration there was an 8% increase in revision rate, which remained after correction for age, sex, diagnosis, hospital type, continent, and study quality. Consequently, migration up to 0.5 mm was considered acceptable during the first postoperative year, while migration of 1.6 mm or more was unacceptable. TKPs with migration of between 0.5 and 1.6 mm were considered to be at risk of having revision rates higher than 5% at 10 years.
INTERPRETATION: There was a clinically relevant association between early migration of TKPs and late revision for loosening. The proposed migration thresholds can be implemented in a phased, evidence-based introduction of new types of knee prostheses, since they allow early detection of high-risk TKPs while exposing only a small number of patients.
Authors:
Bart G Pijls; Edward R Valstar; Klaas-Auke Nouta; Josepha Wm Plevier; Marta Fiocco; Saskia Middeldorp; Rob Ghh Nelissen
Publication Detail:
Type:  Comparative Study; Journal Article; Meta-Analysis; Research Support, Non-U.S. Gov't; Review     Date:  2012-11-09
Journal Detail:
Title:  Acta orthopaedica     Volume:  83     ISSN:  1745-3682     ISO Abbreviation:  Acta Orthop     Publication Date:  2012 Dec 
Date Detail:
Created Date:  2012-11-26     Completed Date:  2013-01-24     Revised Date:  2013-07-11    
Medline Journal Info:
Nlm Unique ID:  101231512     Medline TA:  Acta Orthop     Country:  England    
Other Details:
Languages:  eng     Pagination:  614-24     Citation Subset:  IM    
Affiliation:
Department of Orthopaedics, Bio Imaging Group, Leiden University Medical Center, Leiden, the Netherlands. b.g.c.w.pijls@lumc.nl
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Aged
Arthroplasty, Replacement, Knee / adverse effects*,  methods
Female
Follow-Up Studies
Humans
Incidence
Knee Prosthesis*
Male
Middle Aged
Netherlands
Prosthesis Design
Prosthesis Failure*
Reoperation / methods
Risk Assessment
Time Factors
Treatment Outcome
Comments/Corrections

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Full Text
Journal Information
Journal ID (nlm-ta): Acta Orthop
Journal ID (iso-abbrev): Acta Orthop
Journal ID (publisher-id): ORT
ISSN: 1745-3674
ISSN: 1745-3682
Publisher: Informa Healthcare
Article Information
Download PDF
Copyright: © Nordic Orthopaedic Federation
open-access:
Received Day: 29 Month: 2 Year: 2012
Accepted Day: 04 Month: 9 Year: 2012
Print publication date: Month: 12 Year: 2012
Electronic publication date: Day: 26 Month: 11 Year: 2012
Volume: 83 Issue: 6
First Page: 614 Last Page: 624
PubMed Id: 23140091
ID: 3555454
DOI: 10.3109/17453674.2012.747052
Publisher Id: ORT_A_747052_O

Early migration of tibial components is associated with late revision : A systematic review and meta-analysis of 21,000 knee arthroplasties
Bart G Pijls1
Edward R Valstar12
Klaas-Auke Nouta1
Josepha WM Plevier3
Marta Fiocco4
Saskia Middeldorp56
Rob GHH Nelissen1
1Department of Orthopaedics, Bio Imaging Group, Leiden University Medical Center
2Department of Biomechanical Engineering, Faculty of Mechanical, Maritime and Materials Engineering, TU Delft
3Walaeus Library
4Department of Medical Statistics and Bioinformatics, Leiden University Medical Center
5Academic Medical Center, Department of Vascular Medicine, Amsterdam
6Department of Clinical Epidemiology, Leiden University Medical Center, Leiden, the Netherlands.
Correspondence: Correspondence: b.g.c.w.pijls@lumc.nl

Worldwide, several hundred thousand total knee prostheses (TKPs) are implanted each year and this number is expected to increase by a factor of 6 within the next 2 decades (Kurtz et al. 2005, 2007). Most of the new TKP designs have been introduced to the market without being shown to be safe or effective (Sheth et al. 2009). This has resulted in the widespread use of TKPs with failure rates exceeding 10 times the standard of national joint registries (< 5% failures at 10-year follow-up), such as the Accord, St Leger, and Journey-Deuce (Norton et al. 2002, Gilbert et al. 2009, Sheth et al. 2009, Palumbo et al. 2011 (personal communication)). To guarantee patient safety, several countries have developed guidelines, e.g. the NICE guidelines for total hip prostheses (2003). Furthermore, it has become increasingly evident that a phased, evidence-based introduction, as is common for pharmaceuticals, is needed to regulate the introduction of new TKPs to the market (Malchau 2000, McCulloch et al. 2009, Schemitsch et al. 2010). This should include systematic assessment and early detection of the major cause of TKP failure, which is aseptic loosening of the tibial component necessitating revision surgery (2003, AJR 2010).

Although it can take 10 years before loosening causes symptoms, it is possible to detect loosening early postoperatively using radiostereometric analysis (RSA) (Selvik 1989, Grewal et al. 1992, Karrholm et al. 1994, Ryd et al. 1995). Since RSA allows in vivo, 3D measurement of the migration of TKPs with an accuracy of 0.2 mm for translations and 0.5 degrees for rotations, only a small number of patients need be exposed to potentially unsafe TKPs (Grewal et al. 1992, Ryd et al. 1995, Nelissen et al. 1998). RSA could therefore play an important role in the phased, evidence-based introduction of new TKPs (Selvik 1989, Karrholm et al. 1994, Ryd et al. 1995). However, the evidence for the relationship between early migration and TKP revision for aseptic loosening is limited to a few studies from the 1990s (Grewal et al. 1992, Ryd et al. 1995). Furthermore, the applicability of these studies is restricted, because surgical technique, fixation methods, implant design, and polyethylene have evolved since their publication.

We hypothesized that early migration of the tibial component, measured through RSA, is associated with late revision for aseptic loosening of TKPs. We therefore systematically reviewed the association between early migration and late aseptic revision for the tibial component in TKPs. This could ultimately lead to clinical guidelines to be used in a phased introduction of new TKPs.


Material and methods

We performed two parallel systematic reviews (international registration number NTR2417; www.trialregister.nl) of studies of patients who received TKPs for end-stage osteoarthritis (OA) or rheumatoid arthritis (RA). One review comprised data on early migration of TKPs from RSA studies. From the other, we determined the long-term revision rates for aseptic loosening of TKPs from survival studies (Figure 1). During all stages of the review process, a referee (RN) with over 20 years of experience in both RSA and TKR was available for consultation.

Systematic review of RSA studies

Literature search. A thorough literature search was performed together with a medical librarian (JP), to reduce bias by increasing the likelihood of retrieving all relevant studies (Vochteloo et al. 2010). The following bibliographies were searched up to 2009: PubMed, Embase, Web-of-Science, and the Cochrane Library. Relevant articles were screened for additional references. Additionally, a separate search was conducted in 9 leading orthopedic and biomechanical journals (Acta Orthop, Clin Orthop Relat Res, J Arthroplasty, J Bone Joint Surg (Am and Br), Knee Surg Sports Traumatol Arthrosc, J Orthop Res, J Biomech, and Clin Biomech). Finally, Google Scholar was used. Articles in English, French, Italian, Spanish, Dutch, and German were considered. The search strategy consisted of the following components, each defined by a combination of controlled vocabulary and free text terms: (1) RSA, and (2) joint replacement. See Appendix (Supplementary data) for more details on the strategy and terms.

Inclusion and exclusion analysis. Initial screening on the basis of title and abstract of RSA studies was performed by BP to identify studies on patients treated with TKPs for OA or RA. When the information in the abstract did not suffice or where there was any doubt, the studies remained eligible. The full text of eligible studies was independently evaluated in duplicate by 2 reviewers (BP and EV). The inclusion criteria for RSA studies were: (1) primary TKP, and (2) minimal RSA follow-up of 1 year, measuring tibial component migration. Non-clinical studies (animal, phantom) were excluded.

Data extraction. BP and KN independently extracted migration data in duplicate from the RSA studies. Migration data comprised translations, rotations, and maximal total point motion (MTPM) of the tibial component in the first postoperative year. MTPM is the unit of measurement for the largest 3D migration of any point on the prosthesis surface (Ryd et al. 1995). Data concerning patient demographics and regional influences were also extracted to allow for confounder correction.

Quality assessment. The quality of the RSA studies was independently appraised in duplicate by BP and KN at the level of outcome using the AQUILA methodological score (Pijls et al. 2011). For the RSA studies, we modified the AQUILA by removing items not considered relevant for early migration: long-term follow-up and the revision assessment.

Systematic review of survival studies

Literature search. The search strategy and bibliographies were the same as those in the RSA review, with the exception of the components of the search strategy. The search strategy for the survival studies consisted of the following components, each defined by a combination of controlled vocabulary and free text terms: (1) joint replacement, (2) implant failure, and (3) survival analysis. See Appendix for more details of the strategy and terms. In the search strategy, no distinction was made between total knee prostheses and total hip prostheses (THPs), because some studies reported on both TKPs and THPs (Ryd 1992).

Inclusion and exclusion analysis. The procedure of screening the survival studies for eligibility, and subsequent inclusion and exclusion analysis, was identical to the procedures for the RSA studies, with the exception of inclusion and exclusion criteria. The inclusion criteria for survival studies were (1) primary TKP; (2) follow-up of 5, 10, 15, 20, or 25 years; (3) endpoint revision surgery for aseptic loosening of the tibial component, or indication for revision surgery in patients with poor general health or decline; and (4) survival or percentage revised to be available for specific follow-up (see point 2). Studies with less than 75 TKPs at baseline were excluded.

Data extraction. From the survival studies, BP and KN independently determined the revision rates for aseptic loosening of the tibial component at 5-year intervals. Data concerning patient demographics and regional influences were extracted to allow for confounder correction.

Quality assessment. The quality of the survival studies was independently appraised in duplicate by BP and KN at the level of outcome using the AQUILA methodological score (Pijls et al. 2011).

Analysis

A detailed description of the analysis, methodology, and a worked example are available in the online Appendix (see Supplementary data). To determine the association between early migration and late revision, we matched the results from the RSA review to the results of the survival review on type of prosthesis, fixation method (e.g. cement or bone ingrowth), and articulating insert (e.g. modular or non-modular). The combination was termed PFI. Since PFI involves technical factors known to be associated with both migration and the likelihood of revision for aseptic loosening, matching on PFI prevents confounding by PFI (DKAR 2009, NJR 2009, AJR 2010, SKAR 2010). Depending on the studies available, it was possible that there would be more than 1 combination of matching RSA and survival studies for a particular PFI. For instance, if there are 3 RSA studies and 2 survival studies for the same PFI, then there are 6 possible combinations (3 times 2). All combinations were considered in the analysis. A meta-analysis for the revision rate at 5 years was performed. A model for the censoring mechanism was employed to reconstruct the data and then a generalized linear mixed model with study as a random effect was applied to estimate the survival at 5 years and its 95% confidence interval (CI) (Fiocco et al. 2009, 2011, Putter et al. 2009). Regarding the RSA studies, pooling of migration results at the level of PFI was based on weights according to study size (N).

The 10-year results for TKPs with high revision rates may not be published once the 5-year results have been published. Since 10-year revision rates in the registries are on average 1.7 times higher than 5-year revision rates, any missing 10-year results were estimated on 5-year results by applying a factor of 1.7. This method was validated by comparing the estimated 10-year results with the known 10-year results, for the complete cases (DKAR 2009, NJR 2009, AJR 2010, SKAR 2010).

Adjustment for confounding

Since migration data and revision rate data were extracted from different studies, differences between study populations might confound the observed association. In order to address this issue, we determined the degree of similarity of the population from RSA and survival study combinations, expressed by a match score, for age, sex, diagnosis, hospital type, and continent. The match score was constructed according to the results of a recent Delphi survey among an international group of 37 independent experts, and can vary between 5 (excellent) and 0 (poor) (Pijls et al. 2011). The RSA study and survival study combination scored 1 point for each of the following 5 criteria (up to a maximum of 5 points): (1) the difference in mean age between the patients from RSA study and those from the survival study was 5 years or less; (2) the difference in percentage of females between the RSA study and survival study was 10% or less; (3) the difference in percentage of patients diagnosed with osteoarthritis between the RSA study and the survival study was 10% or less; (4) the RSA study and the survival study were performed in similar types of hospital (e.g. both university medical centers); (5) the RSA study and the survival study were performed on the same continent. All other cases scored zero points.

We used a weighted regression model to assess the association between early migration and late aseptic revision corrected for match score, RSA study quality, survival study quality, number of TKP in the RSA studies, and number of TKP in the survival studies.

Migration thresholds

According to the principle of “primum non nocere“ (first do no harm), new implant designs should perform at least as well as the revision standard of national registries: < 3% revision at 5 years and < 5% revision at 10 years (DKAR 2009, NJR 2009, AJR 2010, SKAR 2010). Based on this revision standard, the following 3 categories were constructed for the phased introduction of new TKPs: “acceptable”, “at risk”, and “unacceptable”. The “acceptable” category was defined as the level of migration up to which all survival studies have lower revision rates than the standard. The “unacceptable” category was defined as the level of migration from which all revision rates are higher than the standard. The category “at risk” was defined as the migration interval between the “acceptable” and “unacceptable” thresholds, in which studies with revision rates lower and higher than the standard were observed.

Appraisal of publication bias

We assessed the potential effect of publication bias by comparing the results from the meta-analysis to the results from national joint registries, since they do not suffer from publication bias (DKAR 2009, NJR 2009, AJR 2010, SKAR 2010). Accordingly, the PFI combinations that perform better than average in the meta-analysis should also perform better than average in the national joint registries. The same principle also applies to PFI combinations that perform worse than average. For this purpose, the migration pooled according to the specific combination of prosthesis type, fixation method and articulating insert (PFI) and visualized in a dot chart (Jacoby 2006).


Results
RSA studies

The literature search yielded 629 hits for the RSA review and 50 studies were included, covering a total of 847 patients (Ryd et al. 1986, 1987, 1988, 1990, 1993, Albrektsson et al. 1990, 1992, Nilsson et al. 1991, 1993, 1998, 2006, Hilding et al. 1995, 2006, 2007, Nielsen et al. 1995, Nelissen et al. 1998, Onsten et al. 1998, Toksvig-Larsen et al. 1998, Adalberth et al. 1999, 2000, 2001, 2002, Østgaard et al. 1999, Li et al. 2000, Toksvig-Larsen et al. 2000, Uvehammer et al. 2001, Hildebrand et al. 2003, Catani et al. 2004, Kienapfel et al. 2004, Norgren et al. 2004, Dalen et al. 2005, Hyldahl et al. 2005a, b, Henricson et al. 2006, Muller et al. 2006, van der Linde et al. 2006a,b, Uvehammer et al. 2007, Wilson et al. 2007, Hansson et al. 2008, Henricson et al. 2008, Therbo et al. 2008, von Schewelov et al. 2008). Details of the study selection and flow of the review are given in Figure 1. The mean quality score of the RSA studies was 3.8 (SD 1.7) on a 7-point scale. MTPM at 1 year was the most frequently and most consistently reported migration value: 44 out of 50 RSA studies reported it. Translations and rotations of the tibial component were reported infrequently and inconsistently, and did not allow a meaningful analysis. Thus, all analyses focused on MTPM at 1 year.

Early migration and late revision

The matching procedure resulted in 28 different PFI combinations and 89 combinations of RSA and survival studies (Table 1). There was a clear association between early migration, expressed as MTPM at 1 year, and the 5-year revision rate as expressed as prosthesis survival (Figure 2). For every mm of increase in migration, 7.6% (CI: 5.7–9.5) was added to the 5-year revision rate (p < 0.001). The influence of RSA study quality, survival study quality, number of TKPs in the RSA study, number of TKPs in the survival study, and match score were small relative to the overall effect of migration on revision rate (Table 2).

For TKPs that rely on primary fixation (cemented and uncemented with screws), 7.1% (CI: 4.7–9.5) was added to the 5-year revision rate for every 1 mm increase in MTPM (p <0.001). For TKPs that rely on secondary fixation (uncemented without screws), 10% (CI: 2.7–17) was added to the 5-year revision rate for every 1 mm increase in MTPM (p = 0.018).

Migration thresholds

Figure 3 shows the 3 categories for the migration of TKP. For MTPM at 1 year of between 0 mm and 0.54 mm, there was no tibial component with more than 3% revision for aseptic loosening at 5 years. With 1-year MTPM of more than 1.6 mm, no tibial components had less than 3% revision for aseptic loosening at 5 years. This indicates that acceptance of 3% revision at 5 years resulted in a threshold of 0.54 mm or acceptable MTPM at 1 year, and a threshold of 1.6 mm for unacceptable MTPM at 1 year. For the 10-year revision rates, the thresholds for acceptable and unacceptable migration were 0.45 mm and 1.6 mm, respectively (Figure 4).

The mean difference between the estimated 10-year revision rate and the known 10-year revision rate was 0.17% (SD 2.1), indicating that there was no systematic error. The 5-year revision rates for the studies with missing 10-year revision rates were already higher than the 10-year revision rate of 5% that is considered to be acceptable. Thus, the 10-year thresholds were not influenced by any missing values.

Publication bias

The pooled MTPM ranked by the pooled revision rate for each PFI combination is presented in Figure 5. The PFI combinations that migrated statistically significantly less than the acceptable threshold—classified as acceptable—have had excellent track records and low revision rates in several national joint registries (DKAR 2009, NJR 2009, AJR 2010, SKAR 2010). Conversely, the PFI combinations that were classified as unacceptable on basis of their pooled migration have been abandoned and are no longer used. The possible influence of publication bias on the results was therefore small.


Discussion

The results of this systematic review show a clinically relevant association between early migration, as measured with RSA, and long-term clinical failure resulting in revision for aseptic loosening. Each mm of migration was associated with an increase in 5-year revision rate of 8%, which remained after correction for age, sex, diagnosis, hospital type, continent, and study quality. This is more than twice the standard revision rate of several national joint registries (DKAR 2009, NJR 2009, AJR 2010, SKAR 2010). The results of this systematic review show that RSA studies can identify unsafe TKPs (in terms of aseptic loosening) as early as 1 year postoperatively. Early identification of unsafe TKPs with RSA should prevent their widespread use and save numerous patients from extensive revision surgery, possibly with postoperative complications.

Some strengths of this systematic review are the large numbers of studies included (> 100) and of patients included (> 27,000), which resulted in 28 different PFI combinations. This large variation, which reflects the diversity of TKP designs and fixation methods, ensures wide generalizability of the results. Since the migration and revision rates were from different studies, there were no migration data available in the survival studies to be incorporated into the decision to perform a revision. Thus, there is no incorporation bias in our results. We consider the risk of publication bias in this systematic review to be small, since the results from the meta-analysis are similar to those from the national joint registries, which do not suffer from publication bias. Confounders had only a small influence on the association between early migration and long-term aseptic revision.

We should also consider some limitations. The quality of the survival and RSA studies showed large variation. High methodological quality of all the studies included would have been desirable. Nevertheless, the quality of the survival studies and the RSA studies showed only very small effects on the association between migration and revision rates.

We focused on MTPM at 1 year postoperatively, but other migration parameters and follow-up beyond 1 year would also be of interest (Ryd et al. 1995). Unfortunately, these parameters were reported too infrequently and inconsistently to permit a meaningful analysis. Future RSA studies could therefore benefit from further standardization, particularly regarding the reporting of the results (Valstar et al. 2005).

We also recognize that RSA only evaluates aseptic loosening while other failure mechanisms (e.g. infection, pain, and instability or pseudotumors in metal-on-metal total arthroplasty) cannot be evaluated by RSA. As a consequence, RSA studies are only the first step in the phased, evidence-based introduction of TKPs—as proposed by Malchau (2000); see Figure 6. During phase A, several single-center RSA studies should be performed to determine the safety of the TKP with regard to the risk of revision for aseptic loosening. If the TKP is considered safe, phase B studies should be conducted to evaluate the clinical performance of the TKP regarding pain relief and functioning (clinical scores and patient-reported outcome measures (PROMS)) and to determine the rate of expected or unexpected complications. Since RSA studies have already evaluated the risk of aseptic loosening, follow-up of 2 years instead of 10 years would be sufficient. This reduces the follow-up needed for a successful phased introduction by almost a decade compared to traditional cohort studies. After release on the market (phase C), the performance of the TKP must be monitored by post-marketing surveillance in national joint replacement registries (Schemitsch et al. 2010). This includes both the revision rate and patient evaluations using PROMS.

In this systematic review, RSA studies of 20–60 patients followed for 1 year led to the same conclusion as national joint registries with thousands of patients followed for 5–10 years. A recent publication has shown a 22–35% reduction in the number of revisions of RSA-tested total knee replacements as compared to non-RSA-tested total knee replacements in the national joint registries (Nelissen et al. 2011). Because inferior designs can already be detected early postoperatively, exposing only a small group of patients to potentially unsafe TKPs, RSA provides the necessary efficiency to make possible phased, evidence-based introduction. Now the observed association between early migration and long-term revision translates into practical thresholds that can lead to clinical guidelines for phased, evidence-based introduction of new TKPs.

Various authors and regulatory agencies recognize the potential of RSA (Grewal et al. 1992, Bulstrode et al. 1993, Karrholm et al. 1994, Ryd et al. 1995, Malchau 2000, Hauptfleisch et al. 2006). The NICE guidelines of 2003 (UK) require adequate long-term clinical data for hip prostheses and indicate that RSA is an alternative to long-term follow-up studies. The Dutch Orthopaedic Society now requires a phased introduction with mandatory RSA studies before any new hip prosthesis is considered for introduction to the Dutch market (2011). Official guidelines for knee prostheses are expected to follow.

In light of the recent disasters with introduction of new orthopedic implants to the market, a phased, clinical introduction for new TKPs is mandatory to prevent patients from receiving potentially unsafe TKPs when standard TKPs with excellent long-term track records are available.

In conclusion, we found a clinically relevant association between early migration of TKPs and late revision for loosening. The proposed migration thresholds can be implemented in a phased, evidence-based introduction, since they allow early detection of TKPs with a high risk of aseptic loosening while exposing only a small number of patients.


RN, BP, and EV had the idea for the study. SM provided methodological input and MF provided statistical input during the conceptual phase of the study. JP designed the search strategy for the literature search. BP and EV performed the study selection and matching procedure. KN and BP appraised the quality of the literature and performed the data extraction. MF and BP analyzed the data. BP, KN, EV, and RN wrote the initial draft manuscript. MF and SM ensured the accuracy of data and analysis. BP and MF wrote the Appendix. Critical revision of the manuscript was performed by all authors. All authors read and approved the final manuscript.

The authors thank the Atlantic Innovation Fund (Atlantic Canada Opportunities Agency) for providing funding for this study (contract no. 191933). The Atlantic Innovation Fund did not take part in the design or conduct of the study; in the collection, management, analysis, or interpretation of the data; or in the preparation, review, or approval of the manuscript.

Data sharing

The statistical code and dataset are available upon request from the corresponding author at b.g.c.w.pijls@lumc.nl. R code for the analysis described in the Appendix is available from one of the authors (m.fiocco@lumc.nl).Supplementary data


Supplementary data

Appendix is available at our website (www.actaorthop.org), identification number 5477.


References
Adalberth G,Nilsson KG,Bystrom S,Kolstad K,Mallmin H,Milbrink J. Stability assessment of a moderately conforming all-polyethylene tibial component in total knee arthroplasty: a prospective RSA study with 2 years of follow-up of the Kinemax Plus designAm J Knee SurgYear: 19991242334010626915
Adalberth G,Nilsson KG,Bystrom S,Kolstad K,Milbrink J. Low-conforming all-polyethylene tibial component not inferior to metal-backed component in cemented total knee arthroplasty: prospective, randomized radiostereometric analysis study of the AGC total knee prosthesisJ ArthroplastyYear: 20001567839211021456
Adalberth G,Nilsson KG,Bystrom S,Kolstad K,Milbrink J. All-polyethylene versus metal-backed and stemmed tibial components in cemented total knee arthroplasty. A prospective, randomised RSA studyJ Bone Joint Surg (Br)Year: 20018368253111521922
Adalberth G,Nilsson KG,Karrholm J,Hassander H. Fixation of the tibial component using CMW-1 or Palacos bone cement with gentamicin: similar outcome in a randomized radiostereometric study of 51 total knee arthroplastiesActa Orthop ScandYear: 2002735531812440496
AJRAustralian Orthopaedic Association National Joint Replacement Registry Annual Report 2010http://wwwdmacadelaideeduau/aoanjrr/publicationsjsp?section=reports2010 2010:accessed 12-05-2011.
Albrektsson BE,Ryd L,Carlsson LV,Freeman MA,Herberts P,Regner L,et al. The effect of a stem on the tibial component of knee arthroplasty. A roentgen stereophotogrammetric study of uncemented tibial components in the Freeman-Samuelson knee arthroplastyJ Bone Joint Surg (Br)Year: 199072225282312565
Albrektsson B EJ,Carlsson LV,Freeman M AR,Herberts P,Ryd L. Proximally cemented versus uncemented Freeman-Samuelson knee arthroplasty. A prospective randomised studyJ Bone Joint Surg (Br)Year: 199274223381544959
Anderson JA,Baldini A,Sculco TP. Patellofemoral function after total knee arthroplasty: a comparison of 2 posterior-stabilized designsJ Knee SurgYear: 20082191618500058
Ansari S,Ackroyd CE,Newman JH. Kinematic posterior cruciate ligament-retaining total knee replacements. A 10-year survivorship study of 445 arthroplastiesAm J Knee SurgYear: 19981119149533047
Arora J,Ogden AC. Osteolysis in a surface-cemented, primary, modular Freeman-Samuelson total knee replacementJ Bone Joint Surg (Br)Year: 200587111502616260667
Berger R,Lyon JH,Jacobs JJ,Barden RM,Berkson EM,Sheinkop MB,et al. Problems with cementless total knee arthroplasty at 11 years follow-upClin OrthopYear: 2001a39219620711716383
Berger RA,Rosenberg AG,Barden RM,Sheinkop MB,Jacobs JJ,Galante JO. Long-term followup of the Miller-Galante total knee replacementClin OrthopYear: 2001b388586711451133
Bertin KC. Tibial component fixation in total knee arthroplasty: a comparison of pegged and stemmed designsJ ArthroplastyYear: 2007225670817689774
Bozic KJ,Kinder J,Menegini M,Zurakowski D,Rosenberg AG,Galante JO. Implant survivorship and complication rates after total knee arthroplasty with a third-generation cemented systemClin OrthopYear: 20054301172415662312
Buehler KO,Venn-Watson E,D’Lima DD,Colwell CW Jr. The press-fit condylar total knee system: 8- to 10-year results with a posterior cruciate-retaining designJ ArthroplastyYear: 200015669870111021444
Bulstrode CJ,Murray DW,Carr AJ,Pynsent PB,Carter SR. Designer hipsBmjYear: 1993306688073238490332
Campbell DG,Duncan WW,Ashworth M,Mintz A,Stirling J,Wakefield L,et al. Patellar resurfacing in total knee replacement. A ten year randomised prospective trialJ Bone Joint Surg (Br)Year: 200688734916720765
Catani F,Leardini A,Ensini A,Cucca G,Bragonzoni L,Toksvig-Larsen S,et al. The stability of the cemented tibial component of total knee arthroplasty: posterior cruciate-retaining versus posterior-stabilized designJ ArthroplastyYear: 20041967758215343540
Chana R,Shenava Y,Nicholl AP,Lusted FJ,Skinner PW,Gibb PA. Five to 8 year results of the uncemented Duracon total knee arthroplasty systemJ ArthroplastyYear: 20082356778218534393
Clayton R A,Amin A,Gaston MS,Brenkel IJ. Five year results of the Sigma total knee arthroplastyThe KneeYear: 2006133596416931026
Dalen T,Nilsson KG. VersaBond bone cement prospective randomized study of the clinical properties of a new bone cement in total knee replacementKneeYear: 2005124311716026700
Dalury DF,Barrett WP,Mason JB,Goldstein WM,Murphy J,Roche MW. Midterm survival of a contemporary modular total knee replacementJ Bone Joint Surg (Br)Year: 2008901594619043130
Dutch Orthopaedic Society (NOV) guideline total hip prosthesis 2011http://www.kwaliteitskoepel.nl/assets/structured-files/2011/Richtlijn+Totale+Heupprothese+2010+zonder+watermerk.pdf
DKARDanish Knee Arthroplasty Registry Report 2009http://wwwkneedk/groups/dkr/pdf/DKRreportEnglish2010pdf 2009:accessed 12-05-2011.
Emerson RH,Higgins LL,Head WC. The AGC total knee prosthesis at average 11 yearsJ ArthroplastyYear: 20001544182310884199
Ewald FC,Wright RJ,Poss R,Thomas WH,Mason MD,Sledge CB. Kinematic total knee arthroplasty: a 10- to 14-year prospective follow-up reviewJ ArthroplastyYear: 19991444738010428229
Faraj AA,Nevelos AB,Nair A. A 4- to 10-year follow-up study of the Tricon-M noncemented total knee replacementOrthopedicsYear: 200124121151411770092
Fetzer GB,Callaghan JF,Templeton JE,Goetz D,Sullivan PM,Kelly SS. Posterior cruciate-retaining modular total knee arthroplasty. A 9- to 12 year follow-up investigationJ ArthroplastyYear: 2002178961612478504
Fiocco M,Putter H,Houwelingen JC. Meta-analysis of pairs of survival curves under heterogeneity: a Poisson correlated gamma frailty approach” Statistics in MedicineStat MedYear: 2009283037829719899066
Fiocco M,Stijnen T,Putter H. Meta-analysis of time-to-event outcomes using a hazard-based approach: Comparison with other models, robustness and meta-regressionComputational Statistics and Data AnalysisYear: 2011 doi:10.1016/j.csda.2011.05.009.
Forster MC,Kothari P,Howard PW. Minimum 5-year follow-up and radiologic analysis of the all-polyethylene tibial component of the Kinemax Plus systemJ ArthroplastyYear: 200217219620011847619
Gilbert RE,Carrothers AD,Gregory JJ,Oakley MJ. The St. Leger total knee replacement: a 10-year clinical and radiological assessmentKneeYear: 2009165322519376710
Gill GS,Joshi AB. Long-term results of Kinematic Condylar knee replacement. An analysis of 404 kneesJ Bone Joint Surg (Br)Year: 2001833355811341419
Gioe TJ,Stroemer ES,Santos ER. All-polyethylene and metal-backed tibias have similar outcomes at 10 years: a randomized level I [corrected] evidence studyClin OrthopYear: 200645512816951639
Goldberg VM,Figgie MP,Figgie HE III,Heiple KG,Sobel M. Use of a total condylar knee prosthesis for treatment of osteoarthritis and rheumatoid arthritis. Long-term resultsJ Bone Joint Surg (Am)Year: 1988706802113392077
Goldberg VM,Kraay M. The outcome of the cementless tibial component. A minimum 14 year clinical evaluationClin OrthopYear: 20044282142015534545
Grewal R,Rimmer MG,Freeman MA. Early migration of prostheses related to long-term survivorship. Comparison of tibial components in knee replacementJ Bone Joint Surg (Br)Year: 1992742239421544960
Hansson U,Ryd L,Toksvig-Larsen S. A randomised RSA study of Peri-Apatite HA coating of a total knee prosthesisKneeYear: 2008153211618329882
Hauptfleisch J,Glyn-Jones S,Beard DJ,Gill HS,Murray DW. The premature failure of the Charnley Elite-Plus stem: a confirmation of RSA predictionsJ Bone Joint Surg (Br)Year: 20068821798316434520
Henricson A,Dalen T,Nilsson KG. Mobile bearings do not improve fixation in cemented total knee arthroplastyClin OrthopYear: 20064481142116826105
Henricson A,Linder L,Nilsson KG. A trabecular metal tibial component in total knee replacement in patients younger than 60 years: A two-year radiostereophotogrammetric analysisJ Bone Joint Surg (Br)Year: 2008901215859319043129
Hildebrand R,Trappmann D,Georg C,Muller HH,Koller M,Klose KJ,et al. What effect does the hydroxyapatite coating have in cementless knee arthroplasty?OrthopadeYear: 20033243233012707697
Hilding MB,Yuan X,Ryd L. The stability of three different cementless tibial components. A randomized radiostereometric study in 45 knee arthroplasty patientsActa Orthop ScandYear: 19956612177863762
Hilding M,Aspenberg P. Postoperative clodronate decreases prosthetic migration: 4-year follow-up of a randomized radiostereometric study of 50 total knee patientsActa OrthopYear: 2006776912617260200
Hilding M,Aspenberg P. Local peroperative treatment with a bisphosphonate improves the fixation of total knee prostheses: a randomized, double-blind radiostereometric study of 50 patientsActa OrthopYear: 2007786795918236186
Hsu R WW,Tsai YH,Huang TJ,Chang J CC. Hybrid total knee arthroplasty: A 3- to 6-year outcome analysisJ Formos Med AssocYear: 199897641059650470
Hyldahl H,Regner L,Carlsson L,Karrholm J,Weidenhielm L. All-polyethylene vs. metal-backed tibial component in total knee arthroplasty-a randomized RSA study comparing early fixation of horizontally and completely cemented tibial components: part 1. Horizontally cemented components: AP better fixated than MBActa OrthopYear: 2005a7667697716470428
Hyldahl H,Regner L,Carlsson L,Karrholm J,Weidenhielm L. All-polyethylene vs. metal-backed tibial component in total knee arthroplasty-a randomized RSA study comparing early fixation of horizontally and completely cemented tibial components: part 2. Completely cemented components: MB not superior to AP componentsActa OrthopYear: 2005b7667788416470429
Jacoby WG. The Dot Plot: A Graphical Display for Labeled Quantitative ValuesThe Political MethodologistYear: 2006141614
Karrholm J,Borssen B,Lowenhielm G,Snorrason F. Does early micromotion of femoral stem prostheses matter? 4-7-year stereoradiographic follow-up of 84 cemented prosthesesJ Bone Joint Surg (Br)Year: 199476691277983118
Khaw FM,Kirk LM,Gregg PJ. Survival analysis of cemented Press-Fit Condylar total knee arthroplastyJ ArthroplastyYear: 2001162161711222888
Khaw FM,Kirk LM,Morris RW,Gregg PJ. A randomised, controlled trial of cemented versus cementless press-fit condylar total knee replacementJ Bone Joint Surg (Br)Year: 2002846586612188480
Kienapfel H,Hildebrand R,Neumann T,Specht R,Koller M,Celik I,et al. The effect of Palamed G bone cement on early migration of tibial components in total knee arthroplastyInflamm Res (Suppl 2)Year: 200453S159S63
Kim YH,Yoon SH,Kim JS. The long-term results of simultaneous fixed-bearing and mobile-bearing total knee replacements performed in the same patientJ Bone Joint Surg (Br)Year: 2007891013172317957070
Knight JL,Atwater RD,Grothaus L. Clinical results of the modular porous-coated anatomic (PCA) total knee arthroplasty with cement: a 5-year prospective studyOrthopedicsYear: 199720111025339397431
Kurtz S,Mowat F,Ong K,Chan N,Lau E,Halpern M. Prevalence of primary and revision total hip and knee arthroplasty in the United States from 1990 through 2002.J Bone Joint Surg (Am)Year: 200587714879715995115
Kurtz S,Ong K,Lau E,Mowat F,Halpern M. Projections of primary and revision hip and knee arthroplasty in the United States from 2005 to 2030J Bone Joint Surg (Am)Year: 2007894780517403800
Lachiewicz PF,Soileau ES. Patella maltracking in posterior-stabilized total knee arthroplastyClin OrthopYear: 2006452155816936588
Laskin RS. Total condylar knee replacement in patients who have rheumatoid arthritis. A ten-year follow-up studyJ Bone Joint Surg (Am)Year: 1990724529352324139
Li MG,Nilsson KG. The effect of the preoperative bone quality on the fixation of the tibial component in total knee arthroplastyJ ArthroplastyYear: 2000157445311021450
Malchau H. Introducing new technology: a stepwise algorithmSpine (Phila PaYear: 19762000253285
Mayman D,Bourne RB,Rorabeck CH,Vaz M,Kramer J. Resurfacing versus not resurfacing the patella in total knee arthroplasty: 8- to 10-year resultsJ ArthroplastyYear: 2003185541512934203
McCulloch P,Altman DG,Campbell WB,Flum DR,Glasziou P,Marshall JC,et al. No surgical innovation without evaluation: the IDEAL recommendationsLancetYear: 2009374969511051219782876
Mont MA,Yoon TR,Krackow KA,Hungerford DS. Eliminating patellofemoral complications in total knee arthroplasty: clinical and radiographic results of 121 consecutive cases using the Duracon systemJ ArthroplastyYear: 19991444465510428225
Moran CG,Pinder IM,Lees TA,Midwinter MJ. Survivorship analysis of the uncemented porous-coated anatomic knee replacementJ Bone Joint Surg (Am)Year: 1991736848572071618
Muller SD,Deehan DJ,Holland JP,Outterside SE,Kirk LM,Gregg PJ,et al. Should we reconsider all-polyethylene tibial implants in total knee replacement?J Bone Joint Surg (Br)Year: 20068812159660217159170
Nelissen RG,Valstar ER,Rozing PM. The effect of hydroxyapatite on the micromotion of total knee prostheses. A prospective, randomized, double-blind studyJ Bone Joint Surg (Am)Year: 199880111665729840636
Nelissen RG,Pijls BG,Karrholm J,Malchau H,Nieuwenhuijse MJ,Valstar ER. RSA and registries: the quest for phased introduction of new implantsJ Bone Joint Surg (Am) (Suppl 3)Year: 201193625
NHS National Institute for Clinical ExcellenceGuidance on the selection of prostheses for primary total hip replacementYear: 2003http://www.nice.org.uk/nicemedia/pdf/Guidance_on_the_selection_of_hip_prostheses.pdf
Nielsen PT,Berg-Hansen E,Toksvig LS,Ryd L,Rechnagel K,Schroder HM,et al. AGC 2000 tibial components with hydroxyapatite coating - a randomized series followed 5 years with RSA. Acta Orthop Scand (Suppl 265)Year: 19956677
Nilsson KG,Karrholm J. Increased varus-valgus tilting of screw-fixated knee prostheses. Stereoradiographic study of uncemented versus cemented tibial componentsJ ArthroplastyYear: 199385529408245999
Nilsson KG,Dalen T. Inferior performance of Boneloc bone cement in total knee arthroplasty: a prospective randomized study comparing Boneloc with Palacos using radiostereometry (RSA) in 19 patientsActa OrthopScandYear: 199869547983
Nilsson KG,Karrholm J,Ekelund L,Magnusson P. Evaluation of micromotion in cemented vs uncemented knee arthroplasty in osteoarthrosis and rheumatoid arthritis. Randomized study using roentgen stereophotogrammetric analysisJ ArthroplastyYear: 199163265781940933
Nilsson KG,Henricson A,Norgren B,Dalen T. Uncemented HA-coated implant is the optimum fixation for TKA in the young patientClin OrthopYear: 20064481293916826107
NJRNew Zealand National Joint Registry Annual Report 2009 (eleven year report)http://wwwcdhbgovtnz/NJR/ 2009:accessed 12-05-2011.
Norgren B,Dalen T,Nilsson KG. All-poly tibial component better than metal-backed: a randomized RSA studyKneeYear: 20041131899615194094
Norton MR,Vhadra RK,Timperley AJ. The Johnson-Elloy (Accord) total knee replacement. Poor results at 8 to 12 yearsJ Bone Joint Surg (Br)Year: 2002846852512211676
Onsten I,Nordqvist A,Carlsson AS,Besjakov J,Shott S. Hydroxyapatite augmentation of the porous coating improves fixation of tibial components. A randomised RSA study in 116 patientsJ Bone Joint Surg (Br)Year: 1998803417259619929
Østgaard SE,Dirksen KL,Lund B. Hydroxyapatite coating in total knee arthroplasty - a randomised RSA study of tibial componentsActa Orthop (Suppl 289)Year: 1999704
Palumbo B,Henderson E,Edwards PK,Burris B,Gutierrez S,Ancha A,et al. Initial experience of the Journey-Deuce Bicompartimental Knee ProsthesisPersonal communication
Parsch D,Kruger M,Moser MT,Geiger F. Follow-up of 11-16 years after modular fixed-bearing TKAInt OrthopYear: 2008332431518392620
Pijls BG,Dekkers OM,Middeldorp S,Valstar ER,Van der Heide HJ,Van der Linden-Van der Zwaag HM,et al. AQUILA: Assessment of QUality In Lower limb Arthroplasty: An expert Delphi consensus for total knee and total hip arthroplastyBMC Musculoskelet DisordYear: 201112117321781327
Putter H,Fiocco M,Stijnen T. Meta-analysis of diagnostic test accuracy studies with multiple thresholds using survival methodsBiom JYear: 20095219511019924701
Ranawat CS,Flynn WF Jr,Saddler S,Hansraj KK,Maynard MJ. Long-term results of the total condylar knee arthroplasty. A 15-year survivorship studyClin OrthopYear: 1993286941028425373
Ranawat CS,Flynn WF,Deshmukh RG. Impact of modern technique on long-term results of total condylar knee arthroplastyClin OrthopYear: 199430913157994951
Rinonapoli E,Mancini GB,Pucci G,Pazzaglia G,Aglietti P. Arthroplasty of the knee using total condylar prosthesis. Long term results (10 to 17 years) and survival analysisRev Chir Orthop Reparatrice Appar MotYear: 199480322397899641
Ritter MA,Wing JT,Berend ME,Davis KE,Meding JB. The clinical effect of gender on outcome of total knee arthroplastyJ ArthroplastyYear: 2008233331618358368
Robertsson O,Scott G,Freeman M AR. Ten-year survival of the cemented Freeman-Samuelson primary knee arthroplasty - Data from the Swedish Knee Arthroplasty Register and the Royal London HospitalJ Bone Joint Surg (Br)Year: 200084506710855871
Rodricks DJ,Patil S,Pulido P,Colwell CW Jr. Press-fit condylar design total knee arthroplasty. Fourteen to seventeen-year follow-upJ Bone Joint Surg (Am)Year: 2007891899517200315
Ryd L. Roentgen stereophotogrammetric analysis of prosthetic fixation in the hip and knee jointClin OrthopYear: 199227656651537175
Ryd L,Albrektsson BE,Herberts P,Lindstrand A,Selvik G. Micromotion of noncemented Freeman-Samuelson knee prostheses in gonarthrosis. A roentgen-stereophotogrammetric analysis of eight successful casesClin OrthopYear: 1988229205123349679
Ryd L,Lindstrand A,Rosenquist R,Selvik G. Tibial component fixation in knee arthroplastyClin OrthopYear: 198621314193780083
Ryd L,Lindstrand A,Rosenquist R,Selvik G. Micromotion of conventionally cemented all-polyethylene tibial components in total knee replacements. A roentgen stereophotogrammetric analysis of migration and inducible displacementArch Orthop Trauma SurgYear: 198710628283566511
Ryd L,Lindstrand A,Stenstrom A,Selvik G. Porous coated anatomic tricompartmental tibial components. The relationship between prosthetic position and micromotionClin OrthopYear: 1990251189972295173
Ryd L,Carlsson L,Herberts P. Micromotion of a noncemented tibial component with screw fixation. An in vivo roentgen stereophotogrammetric study of the Miller-Galante prosthesisClin OrthopYear: 1993295218258403652
Ryd L,Albrektsson BE,Carlsson L,Dansgard F,Herberts P,Lindstrand A,et al. Roentgen stereophotogrammetric analysis as a predictor of mechanical loosening of knee prostheses. J Bone Joint Surg (Br)Year: 199577337783
Samuelson K,Nelson L. An all-polyethylene cementless tibial component. A five- to nine-year follow-up studyClin OrthopYear: 19902609372225650
Santini AJ,Raut V. Ten-year survival analysis of the PFC total knee arthroplasty–a surgeon’s first 99 replacementsInt OrthopYear: 20083244596517364178
Schemitsch EH,Bhandari M,Boden SD,Bourne RB,Bozic KJ,Jacobs JJ,et al. The evidence-based approach in bringing new orthopaedic devices to marketJ Bone Joint Surg (Am)Year: 20109241030720360530
Schroder HM,Berthelsen A,Hassani G,Hansen EB,Solgaard S. Cementless porous-coated total knee arthroplastyJ ArthroplastyYear: 20011655596711503114
Scott RD. The incidence and causes of re-operation after press-fit condylar (PFC) total knee arthroplastyJ Orthop ScienceYear: 199724652
Selvik G. Roentgen stereophotogrammetry. A method for the study of the kinematics of the skeletal systemActa Orthop Scand (Suppl 232)Year: 1989151
Sextro GS,Berry DJ,Rand JA. Total knee arthroplasty using cruciate-retaining kinematic condylar prosthesisClin OrthopYear: 2001388334011451130
Sheth U,Nguyen NA,Gaines S,Bhandari M,Mehlman CT,Klein G. New orthopedic devices and the FDAJ Long Term Eff Med ImplantsYear: 20091931738420939777
SKARSwedish Knee Arthroplasty Registry Report 2010 V1.0http://wwwkneenkose/english/online/thePages/contactphp 2010:accessed 12-05-2011.
Smith AJ,Wood DJ,Li MG. Total knee replacement with and without patellar resurfacing: a prospective, randomised trial using the profix total knee systemJ Bone Joint Surg (Br)Year: 20089043918160498
Stukenborg-Colsman C,Wirth CJ. Knee endoprosthesis: clinical aspectsOrthopadeYear: 2000298732811013917
Therbo M,Lund B,Jensen KE,Schroder HM. Effect of bioactive coating of the tibial component on migration pattern in uncemented total knee arthroplasty: A randomized RSA study of 14 knees presented according to new RSA-guidelinesJ Orthop TraumaYear: 20082637
Toksvig-Larsen S,Jorn LP,Ryd L,Lindstrand A. Hydroxyapatite-enhanced tibial prosthetic fixationClin OrthopYear: 200037019220010660713
Toksvig-Larsen S,Ryd L,Lindstrand A. Early inducible displacement of tibial components in total knee prostheses inserted with and without cement: a randomized study with roentgen stereophotogrammetric analysisJ Bone Joint Surg (Am)Year: 19988018399469313
Uvehammer J,Karrholm J,Carlsson L. Influence of joint area design on tibial component migration: comparison among a fixed symmetrical, asymmetrical, and moveable bearingJ Knee SurgYear: 200720120617288084
Uvehammer J,Regner L,Karrholm J. Flat vs. concave tibial joint surface in total knee arthroplasty: randomized evaluation of 39 cases using radiostereometryActa Orthop ScandYear: 20017232576511480601
Valstar ER,Gill R,Ryd L,Flivik G,Borlin N,Karrholm J. Guidelines for standardization of radiostereometry (RSA) of implantsActa OrthopYear: 20057645637216195075
van der Linde MJ,Garling EH,Valstar ER,Tonino AJ,Nelissen RG. Periapatite may not improve micromotion of knee prostheses in rheumatoid arthritisClin OrthopYear: 2006a448122816826106
Van der Linde MJ,Grimm B,Garling EH,Valstar ER,Tonino AJ,Heyligers IC. Comparative study of the migration of the tibial tray in total knee arthroplasty for cemented, uncoated and periapatite coated components using roentgenstereogrammetric analysis (RSA)J Bone Joint Surg (Br) (Suppl I)Year: 2006b88967
Vessely MB,Whaley AL,Harmsen WS,Schleck CD,Berry DJ,The Chitranjan Ranawat Award -. Long-term survivorship and failure modes of 1000 cemented condylar total knee arthroplastiesClin OrthopYear: 2006452283416936585
Vochteloo AJ,Pijls BG,van der Heide HJ. Sutures v staples. Let’s add three other studiesBmjYear: 2010340c262720483932
von Schewelov T,Besjakov J,Sanzen L,Carlsson A. A clinical and radiostereometric study of the cemented PFC-sigma prosthesis: a 5-year study of 29 cases with a fixed bearingJ Knee SurgYear: 2008223231619634727
Weir DJ,Moran CG,Pinder IM. Kinematic condylar total knee arthroplasty. 14-year survivorship analysis of 208 consecutive casesJ Bone Joint Surg (Br)Year: 1996786907118951005
Wilson D,Dunbar MJ. A prospective randomized controlled trial using roentgen stereophotogrammetric analysis of a trabecular metal tibial monoblock knee arthroplasty component - 2 year resultsJ BiomechYear: 200740S2S182
Worland RL,Johnson GV,Alemparte J,Jessup DE,Keenan J,Norambuena N. Ten to fourteen year survival and functional analysis of the AGC total knee replacement systemKneeYear: 200292133711950577
Wright J,Ewald FC,Walker PS,Thomas WH,Poss R,Sledge CB. Total knee arthroplasty with the kinematic prosthesis. Results after five to nine years: a follow-up noteJ Bone Joint Surg (Am)Year: 1990727100392384498
Zaki SH,Rafiq I,Kapoor A,Raut V,Gambhir AK,Porter ML. Medium term results with the Press Fit Condylar (PFC) sigma knee prosthesis the wrightington experienceActa Orthop BelgicaYear: 2007731559

Figures

[Figure ID: F1]
Figure 1. 

PRISMA flow chart of both reviews. Details of the 28 PFI combinations are given in Table 1. RSA: radiostereometric analysis; TKP: total knee prosthesis; FU: follow-up; PFI: prosthesis-fixation-insert combination.



[Figure ID: F2]
Figure 2. 

Scatter plot showing association between migration in the first postoperative year expressed as maximal total point motion (MTPM) in mm and revision rate for aseptic loosening of the tibial component at 5 years, as a percentage. The colored lines are derived from weighted regression according to match quality, survival study quality, and RSA study quality (the coefficients and 95% CI are given in Table 2).



[Figure ID: F3]
Figure 3. 

Scatter plot showing the relation between MTPM at 1 year and revision of the tibial component for aseptic loosening at 5 years. The thresholds of 0.54 mm and 1.6 mm for the three categories (acceptable, at risk, and unacceptable) are shown.



[Figure ID: F4]
Figure 4. 

Scatter plot showing the relation between MTPM at 1 year and revision of the tibial component for aseptic loosening at 10 years. The thresholds of 0.45 mm and 1.6 mm for the three categories (acceptable, at risk, and unacceptable) are shown.



[Figure ID: F5]
Figure 5. 

Dot chart showing the pooled MTPM ranked by the pooled revision rate for each PFI combination. The acceptable PFI combinations (based on migration) had excellent track records and low revision rates in several national registries, whereas the unacceptable PFI combinations (based on migration) have been abandoned. Thus, the potential influence of publication bias on the results is small. A detailed description of each PFI combination is given in Table 1. R5(%): pooled revision rate at 5-year follow-up, as a percentage.



[Figure ID: F6]
Figure 6. 

Flow chart showing the role of RSA studies in the phased evidence-based introduction of new TKPs, modified according the Malchau proposal. Stabilization is defined as migration of less than 0.2 mm in the second postoperative year (MTPM from year 1 to year 2) as described by Ryd et al. (1995). See discussion for details of each phase.



Tables
[TableWrap ID: T1] Table 1. 

Prosthesis, Fixation and Insert (PFI) characteristics.


PFI 89
Prosthesis
Fixation Insert Number
of RSA
studies
Number
of survival
studies
Number
of
combinations
1 Anatomic Modular Knee, CR, MB Cement Fixed, Modular 2 2 4
2 Tricon M, PE pegs, MB Porous coated, no stem, no screws Fixed 3 1 3
3 Duracon, CR, MB Cement Fixed, Modular 1 1 1
4 Total Condylar, no CR Cement All PE 1 5 5
5 Freeman-Samuelson Uncoated All PE (HDP) 2 2 4
6 Freeman-Samuelson, PE pegs, MB Uncoated Fixed 1 2 2
7 Anatomic Graduated Component 2000, CR, MB Porous coated Fixed, Non-modular 1 1 1
8 Miller-Galante I, 4 pegs, CR, MB Cement Fixed, Modular 2 1 2
9 Miller-Galante II, 4pegs, CR, MB Cement Fixed, Modular 2 1 2
10 Optetrak, PS, MB, finned stem Cement Fixed 1 1 1
11 Kinemax Plus, no PS Cement All PE 1 1 1
12 Profix, stemmed, CR, MB Cement Fixed, Modular 1 3 3
13 Porous Coated Anatomic, cruciform stem, CR, MB Cement Fixed, Modular 1 1 1
14 Kinematic Condylar, CR, MB Cement Fixed, Non-modular 6 1 6
15 Miller-Galante I, 4 pegs, CR, MB Porous coated, 4 screws Fixed, Modular 2 2 4
16 Anatomic Graduated Component, CR, MB Cement Fixed, Non-Modular 3 3 9
17 Press Fit Condylar, CR, MB Porous coated Fixed, Modular 1 1 1
18 Duracon, CR, MB HA/PA coated Fixed, Modular 1 5 5
19 Press Fit Condylar, CR, MB Cement Fixed, Modular 9 1 9
20 Press Fit Condylar Sigma, CR, MB Cement Fixed, Modular 3 2 6
21 NexGen Legacy, PS, MB Cement Fixed, Modular 2 2 4
22 Freeman-Samuelson, PE pegs, MB Cement Fixed 2 1 2
23 Freeman-Samuelson, metal pegs, MB Cement Fixed, Modular 2 2 4
24 NexGen, CR, MB, stem Cement Fixed, Modular 1 2 2
25 NexGen, 4 pegs, CR, MB Cement Fixed, Modular 1 2 2
26 Miller-Galante II, 4 pegs, CR, MB Porous coated, 4 screws Fixed, Modular 1 2 2
27 Porous Coated Anatomic, no PS, MB, no stem Porous coated, 1 screw Fixed 1 2 2
28 Interax, CR, MB Uncoated Fixed, two halfbearings 2 1 2
Total 50 56 89

CR = cruciate retaining

HA/PA = Hydroxyapatite/periapatite

HDP = high density poly-ethylene

MB = metal backed

PE = poly-ethylene

PS = posterior stabilized


[TableWrap ID: T2] Table 2. 

Association between MTPM at 1 year and revision rate for aseptic loosening at 5 years


Increase in revision (%) /
mm MTPM
95% CI
Crude 7.6 5.7–9.5
Adjusted fora:
 N survival b 7.4 5.6–9.2
 N RSA b 7.1 5.4–8.8
Survival study quality 8.4 6.5–10.3
RSA study quality 7.4 5.4–9.4
Total Match Score 7.6 5.6–9.4
Range of values: 7.1–8.4 5.4–10.3

Table 2 shows the increase in the 5-year revision (%) for each mm increase in MTPM at 1 year. In the crude analysis (unadjusted) 7.6% [95%CI 5.7–9.5], p<0.001, is added to the 5-year revision rate for every mm increase in MTPM at 1 year.

T2-F1a When adjusted for e.g. the number of TKP in survival studies (N survival) 7.4% [95%CI 5.6–9.2], p<0.001, is added to the 5-year revision rate for every mm increase in MTPM at 1 year.

The association between MTPM1 and revision rate for aseptic loosening remains significant, when adjusting for confounders (all p-values <0.001).

T2-F2b The square rote of N was used for the weighted regression, so larger studies weigh heavier.

N survival = number of TKP in survival studies

N RSA = number of TKP in RSA studies



Article Categories:
  • Knee


Previous Document:  Evaluation of a single preoperative dose of etoricoxib for postoperative pain relief in therapeutic ...
Next Document:  Metal-on-metal joint bearings and hematopoetic malignancy.