The Journal of Bone & Joint Surgery

The Journal of Bone & Joint Surgery, Volume 87, Issue 8

Scientific Articles | August 01, 2005

The Functional Outcomes of Total Knee Arthroplasty

Robert L. Kane, MD¹; Khaled J. Saleh, MD, MSc, FRCSC²; Timothy J. Wilt, MD, MPH³; Boris Bershadsky, PhD¹

¹ University of Minnesota School of Public Health, D351 Mayo (MMC 197), 420 Delaware Street S.E., Minneapolis, MN 55455. E-mail address for R.L. Kane: kanex001@umn.edu
² Department of Orthopaedic Surgery, University of Virginia, 400 Ray C. Hunt Drive, Suite 330, Charlottesville, VA 22903. E-mail address: saleh@virginia.edu
³ VA Medical Center, General Internal Medicine (111-0), One Veterans Drive, Minneapolis, MN 55417. E-mail address: tim.wilt@med.va.gov

View Disclosures and Other Information

In support of their research or preparation of this manuscript, one or more of the authors received grants or outside funding from the Agency for Healthcare Research and Quality. None of the authors received payments or other benefits or a commitment or agreement to provide such benefits from a commercial entity. Commercial entities (Stryker Orthopaedics and Smith and Nephew) paid or directed, or agreed to pay or direct, benefits to a research fund, foundation, educational institution, or other charitable or nonprofit organization with which the authors are affiliated or associated.

Investigation performed at the Minnesota Evidence-Based Practice Center, University of Minnesota Clinical Outcomes Research Center, and Minneapolis VA Center for Chronic Disease Outcomes Research, Minneapolis, Minnesota

The Journal of Bone and Joint Surgery, Incorporated

J Bone Joint Surg Am, 2005 Aug 01;87(8):1719-1724. doi: 10.2106/JBJS.D.02714

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Abstract

Background: As an elective procedure, total knee arthroplasty is under scrutiny to evaluate its cost-effectiveness. In this review, we examined the available literature on total knee arthroplasty to assess the evidence regarding factors associated with better functional outcomes.

Methods: A structured literature search of English-language databases was performed to identify studies of the functional outcomes of total knee arthroplasty that had been published between 1995 and April 2003. Inclusion criteria were a study of primary total knee arthroplasty, more than 100 knees in the study, provision of baseline data and rating of postoperative outcomes with a standardized symptom scale, and an experimental or quasi-experimental study design. The abstracting form included a list of potential prognostic factors, including comorbidities, radiographic evidence of joint destruction, bone loss, integrity of the extensor mechanism, range of motion, alignment, tibiofemoral angle, and ligament integrity, as well as the characteristics of the operating surgeon, such as procedure volume and experience.

Results: Sixty-two studies met the criteria and were reviewed. Total knee arthroplasty was found to be associated with substantial functional improvement, with the effect sizes varying with the measure that was used. Physician-derived measures showed effect sizes of 2.35 and 3.91, whereas patient-derived measures showed smaller effect sizes (1.27 and 1.62). Few investigators used multivariate models to identify associations between outcomes and patient characteristics.

Conclusions: Total knee arthroplasty is a generally effective procedure, but the current English-language literature does not support specific recommendations about which patients are most likely to benefit from it.

Level of Evidence: Prognostic Level II. See Instructions to Authors for a complete description of levels of evidence.

Figures in this Article

Total knee arthroplasty is one of the most commonly performed orthopaedic procedures. Medicare data indicate that, in 2001, 171,335 primary knee replacements and 16,895 knee revisions were performed in the United States¹, and other estimates have been substantially higher². Medicare paid approximately $3.2 billion for hip and knee joint replacements in 2000. As is the case in most of the surgical literature, the absence of randomized controlled trials necessitates strong quasi-experimental designs in which multivariate analysis is employed to isolate the effect of treatment. This need is especially acute in establishing the role of an elective surgical procedure such as total knee arthroplasty.

Standardized instruments have been developed in order to assess the severity of symptoms and evaluate the outcomes of treatment. Widely used scales include The Hospital for Special Surgery score (HSS)³, the Knee Society score (KS)⁴, the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)⁵, and the more generic Short Form-36 (SF-36)^6,7. The HSS and KS are completed by clinicians; the WOMAC and SF-36 are designed to be completed by patients.

Previous reports have suggested that total knee arthroplasty improves functional status, relieves pain, and results in relatively low perioperative morbidity⁸. Since 1992, there have been major advances in the understanding of knee biomechanics, biomaterials, and prosthetic designs as well as surgical technique. However, considerable disagreement remains about which patients are most likely to benefit from total knee arthroplasty and, conversely, for which patients total knee arthroplasty is contraindicated or not expected to provide substantial benefit. There is substantial variation in opinion about the indications for surgery among orthopaedic surgeons^9-11 and more so between orthopaedists and rheumatologists and family physicians^12-14.

The objective of our study was to examine the consistency of reports of functional improvement following total knee arthroplasty and to identify factors associated with greater success.

Materials and Methods

The strategy for searching the literature for clinical predictors of the results of total knee arthroplasty was developed in consultation with the National Library of Medicine, which conducted the search. The literature search was done with use of a combination of MeSH (Medical Subject Headings), keywords, and publication types (available at ). The search was limited to studies published from 1995 through April 2003. The start date was chosen because a previous review was published in 1994, even though the investigators in that study had reviewed the literature only through 1992⁸. Animal studies, non-English-language references, and references on unicompartmental (unicondylar) knee replacement were excluded. The titles and abstracts of the resulting 3519 references were then screened to determine whether they met our inclusion criteria (a study of primary total knee arthroplasty, more than 100 knees in the study, provision of baseline data and rating of postoperative outcomes with a standardized symptom scale, and an experimental or quasi-experimental study design). The literature review was initially designed to identify studies with at least the rudiments of a strong quasi-experimental design. However, after the studies were identified, we were forced to revise our criteria to assess a broader array of investigations that provided at least some baseline and follow-up information.

All articles that appeared to meet the screening criteria were abstracted by a team of trained abstractors. Extracted data included study and patient characteristics, baseline and follow-up scores on the symptom scales, revision rates, and perioperative complications (as defined by the authors) occurring within six months after the surgery. A 10% subsample of all of the abstracts was reviewed independently by a second abstractor to ensure consistency, and no factual differences were uncovered. All of the studies that met the minimal criterion of providing preoperative and postoperative data were re-reviewed independently by all three of the study principals (R.L.K., K.J.S., and T.J.W.), and any differences were resolved by discussion.

The abstracting form included a list of potential prognostic factors, developed with the assistance of our technical expert panel (academic orthopaedists and rheumatologists appointed by the Agency for Healthcare Research and Quality [AHRQ]). These factors included comorbidities, radiographic evidence of joint destruction, bone loss, integrity of the extensor mechanism, range of motion, alignment, tibiofemoral angle, and ligament integrity, as well as the characteristics of the operating surgeon, such as procedure volume and experience.

This initial screen identified 611 references that either met the inclusion criteria or needed further screening of the full article to determine whether the inclusion criteria were met. In sixty-two of these studies, preoperative and postoperative functional data were reported according to at least one of the four established measures on which we relied (KS, HSS, WOMAC, or SF-36). All but fifteen studies were conducted in the United States or Canada.

Statistical Methods

We conducted a meta-analysis of the functional outcomes data. Because there was no common functional outcomes measure among all of the studies, we assessed the treatment-effect size of continuous variables on the basis of the mean change (from baseline to the end of study) in each outcome divided by the pooled standard deviation for each outcome. We converted all WOMAC scores to the same 0 to 100-point format used for the other scores; because we were measuring change over time, in effect, we reversed the sign for the few scores that used a 100 to 0-point approach. The statistical results of the meta-analysis were normalized by dividing the combined standard deviation of two (baseline and follow-up) measures and were expressed in the units of standard deviation and reported as an "effect size." In general, an effect size of =0.8 indicates a large effect; 0.5 to 0.79, a moderate effect; and 0.2 to 0.49, a small effect¹⁵. All calculations were implemented with use of the trial version of the Comprehensive Meta Analysis software (Biostat; Englewood, New Jersey)¹⁶.

Results

Baseline Characteristics of the Patients

The sixty-two studies in which preoperative and postoperative functional data were assessed with one of the four established outcome measures are summarized in the Appendix. Table I presents selected patient and clinical characteristics. We used the full sample from each study whenever possible. The mean values were calculated with weighting of means separately on the basis of the numbers of knees and patients in the studies. The weightings made little difference. The number of patients was not reported in two studies.

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TABLE I Descriptive Statistics for the Sixty-two Studies

Patient Characteristics	Average (and Standard Deviation)	No. of Studies in Which Characteristic Reported
Age (yr)	67.5 ± 4.4	57
Weighted by no. of patients	69.1	50
Weighted by no. of knees	69.2	56
Percent female	65.4 ± 17	47
Weighted by no. of patients	64.6	41
Weighted by no. of knees	64.5	47
Percent obese^* (body mass index =30)	36.7 ± 3.5	3^*
Weighted by no. of patients	37.7	3
Weighted by no. of knees	37.3	3
Percent with osteoarthritis	86.8 ± 13	45
Weighted by no. of patients	86.7	40
Weighted by no. of knees	85.6	43

One study in which all patients were obese is not included.

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TABLE I Descriptive Statistics for the Sixty-two Studies

Patient Characteristics	Average (and Standard Deviation)	No. of Studies in Which Characteristic Reported
Age (yr)	67.5 ± 4.4	57
Weighted by no. of patients	69.1	50
Weighted by no. of knees	69.2	56
Percent female	65.4 ± 17	47
Weighted by no. of patients	64.6	41
Weighted by no. of knees	64.5	47
Percent obese^* (body mass index =30)	36.7 ± 3.5	3^*
Weighted by no. of patients	37.7	3
Weighted by no. of knees	37.3	3
Percent with osteoarthritis	86.8 ± 13	45
Weighted by no. of patients	86.7	40
Weighted by no. of knees	85.6	43

One study in which all patients were obese is not included.

The average age of the patients at the time of surgery was 67.5 years, and very few patients were older than eighty-five. About two-thirds (65.4%) of the patients were women, and about one-third (36.7%) were considered to be obese (a body mass index of =30). Nearly 90% (86.8%) of the patients had osteoarthritis. One-third of the patients underwent bilateral total knee arthroplasty. None of the studies provided information regarding racial or ethnic status.

The generic measure (the SF-36) was associated with shorter follow-up periods than the other measures, as determined with weighting by the numbers of patients. In general, determining the sample sizes at different points in time was difficult. A substantial number of reports failed to provide data that were adequate to identify how many patients (or knees) were available at the time of follow-up. The longer established measure, the KS score, was associated with longer follow-up periods. Only eleven studies had a follow-up time of at least ten years, and the majority of those were focused on assessing prostheses or techniques.

Some information on the attrition rate was reported in forty-nine studies, in which a median of 2% (range, 0% to 28%) of the subjects were lost to follow-up. In four studies, >10% were lost to follow-up; in three of those studies the mean duration of follow-up was less than two years, and in one it was 169 months. If deaths and other exclusions are added to the definition of "loss to follow-up," the range increases to 0% to 54% with a median of 12%. Four studies had a total loss rate of >40%; the shortest follow-up period in those studies was fifty-nine months^17-20.

Magnitude of Effect of Primary Total Knee Arthroplasty

Table II summarizes the raw data on the change between the preoperative and postoperative functional scores, albeit in studies with widely varying follow-up periods. The range for each scale was defined as 0 to 100, with higher scores being better. In each study, there was strong evidence of improved function (and decreased pain) following the total knee arthroplasties. Of the forty-six studies in which KS scores were used, only forty-three provided preoperative and postoperative results according to the number of subjects enrolled (n = 12,261 subjects); twenty-seven provided this information on the basis of the number of knees (n = 15,454 knees). HSS scores were used in twenty-two studies involving a total of 2546 patients, and results were reported with the use of WOMAC scores in nine studies representing a total of 2925 patients.

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TABLE II Weighted Baseline and Follow-up Scores for Outcomes Measures in Studies of Total Knee Arthroplasty

	Results Provided According to No. of Subjects					Results Provided According to No. of Knees
Outcome Measure	No. of Studies Reporting Preop. and Postop. Scores	Baseline Score (points)	Follow-up Score (points)	No. of Studies Reporting Preop. and Postop. Scores	Baseline Score (points)	Follow-up Score (points)
Knee Society score (KS)	30/7^* (n = 12,261)	39.8	80.0	27/5† (n = 15,454)	41.1	82.4
Hospital for Special Surgery score (HSS)	17/3^* (n = 2546)	54.2	89.2	16/2† (n = 3333)	52.8	88.7
Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)	7 (n = 2925)	48.3	76.8	‡
Short Form-36 (SF-36) physical function score	8/7^* (n = 2166)	27.6	43.8	2/1†	22.4	47.1

^*The values are given as: total number of studies providing results on the basis of the number of subjects/number of studies providing results on the basis of the number of subjects only. †The values are given as: total number of studies providing results on the basis of the number of knees/number of studies providing results on the basis of the number of knees only. ‡One study only.

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TABLE II Weighted Baseline and Follow-up Scores for Outcomes Measures in Studies of Total Knee Arthroplasty

	Results Provided According to No. of Subjects					Results Provided According to No. of Knees
Outcome Measure	No. of Studies Reporting Preop. and Postop. Scores	Baseline Score (points)	Follow-up Score (points)	No. of Studies Reporting Preop. and Postop. Scores	Baseline Score (points)	Follow-up Score (points)
Knee Society score (KS)	30/7^* (n = 12,261)	39.8	80.0	27/5† (n = 15,454)	41.1	82.4
Hospital for Special Surgery score (HSS)	17/3^* (n = 2546)	54.2	89.2	16/2† (n = 3333)	52.8	88.7
Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)	7 (n = 2925)	48.3	76.8	‡
Short Form-36 (SF-36) physical function score	8/7^* (n = 2166)	27.6	43.8	2/1†	22.4	47.1

Table III summarizes the effect sizes (defined as the number of standard deviations of change) according to the type of measure and the duration of follow-up. Overall, the effect sizes were large and remained so even in studies in which the duration of follow-up was more than five years. The more generic SF-36 scores demonstrated the smallest mean effect size (1.27), but the effect size was still large. The effect size was considerably higher in the studies based on clinicians' reports of the results (with the KS and HSS) than it was in those based on patient-reported measures (the WOMAC and SF-36). There was no relationship between effect sizes and attrition rates.

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TABLE III Summary of Effect-Size Estimates

Measure	0-2 Years of Follow-up (N = 14 Studies)	2.1-5 Years of Follow-up (N = 11 Studies)	>5 Years of Follow-up (N = 19 Studies)
Knee Society score (KS)	2.35	2.73	2.67
Hospital for Special Surgery score (HSS)	3.91	3.01	2.67
Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)	1.62
Short Form-36 (SF-36) physical function score	1.27

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TABLE III Summary of Effect-Size Estimates

Measure	0-2 Years of Follow-up (N = 14 Studies)	2.1-5 Years of Follow-up (N = 11 Studies)	>5 Years of Follow-up (N = 19 Studies)
Knee Society score (KS)	2.35	2.73	2.67
Hospital for Special Surgery score (HSS)	3.91	3.01	2.67
Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC)	1.62
Short Form-36 (SF-36) physical function score	1.27

Correlates of Functional Outcomes

We differentiated "indications for total knee arthroplasty" from "correlates or factors related to outcomes." Only twelve of the sixty-two studies included any direct assessment of the relationship of patient variables to a change in functional status. The descriptor most frequently used in such analyses was body-mass index, followed closely by age and the type of arthritis. Some reports indicated that a relationship was explored but did not provide the specific statistical details of the analysis.

Neither age nor obesity was significantly correlated with the outcomes of total knee arthroplasty; however, caution must be used in interpreting these findings in the face of small samples. In one small study, the improvements in the WOMAC scores for pain, function, and stiffness, after six months of follow-up, were similar in patients older than the age of eighty (n = 35) and those less than the age of eighty (n = 221)²¹. In a study of 1011 patients, Stickles et al. reported a trend toward greater improvement in the WOMAC score, compared with the baseline, with higher body mass indexes (an improvement of 57% for a body mass index of >40 compared with 36% for a body mass index of >25; p = 0.08)²⁰. In one study of 120 subjects, those with rheumatoid arthritis had a greater percent improvement in the HSS score, compared with the baseline, than did those with osteoarthritis²². However, in most of these studies, only one independent variable was examined at a time in simple bivariate analyses. Therefore, improved scores at the time of follow-up could be due to more severe preoperative disease rather than the type of arthritis or the presence of obesity. In the few studies in which more sophisticated statistical methods were used, the duration of follow-up was one year or less, but those studies deserve further attention.

Multiple regression analyses were used in only five studies, and all except the study by Hawker et al.²³ involved fewer than 300 subjects. Jones et al. employed stepwise regression analysis, which may eliminate variables whose contribution is accounted for by another variable²⁴. They used separate models for the two components of the WOMAC score and found no significant relationship between the change in the pain status (from the preoperative to the six-month follow-up evaluation) and age, sex, or body mass index in a series in which most patients had osteoarthritis. However, the effects of the limited sample size (n = 257) should be considered. The significant patient-related predictor of postoperative pain status was preoperative bodily pain (as measured with the SF-36). Other significant predictors were the length of the hospital stay and the use of a cementless prosthesis. Age, sex, and body mass index also were not significant predictors of the change in function, but, again, sample size may have played a role in the findings of that analysis. Patients with a longer length of hospital stay, greater preoperative pain, and comorbid conditions had greater improvement in function.

Deshmukh et al. employed hierarchical multiple regression analysis but did not provide the actual results²⁵. When the authors analyzed changes in function and pain, as measured with the KS, at twelve months after the total knee arthroplasty, they controlled for age and sex. Their results indicated that body mass index accounted for only a small amount of the explained variance.

Fortin et al. used multiple linear regression analysis to examine the effects of age and gender on WOMAC scores at six months in a sample of only 106 patients²⁶. They found no significant relationships between these characteristics and either pain or function, but once again the sample size must be considered.

In a large study of 1193 patients, most of whom were women with osteoarthritis, Hawker et al. analyzed several sources of data in a stepwise multiple regression model with WOMAC scores as the dependent variable²³. Age, gender, and body mass index were not significant predictors of knee pain. However, a lower body mass index predicted better physical function and greater satisfaction with the result of the procedure.

Konig et al. used multiple linear regression analysis to assess KS scores at two years²⁷. Age, gender, and body mass index were not significantly related to pain or the overall KS scores. However, body mass index correlated with functional outcome.

Complications

The rate of perioperative complications, defined rather broadly to include any complications potentially attributable to the surgery that occurred within six months after the surgery, was 8.5% (859 of 10,130) when the analysis was based on knees and 8.2% (859 of 10,501) when it was based on patients. The complication rates were defined by each investigator and were not always reported. The vast majority of the complications were "knee-related" or deep venous thromboses. The absence of reports of cardiopulmonary complications in these studies involving substantial numbers of elderly patients raises questions about the completeness of the reporting of the complications.

Discussion

Total knee arthroplasty improves function, with large mean effect sizes. The strongest evidence has been obtained over two-year follow-up periods, but studies that extended follow-up to five and ten years showed similarly positive results. The results were more positive when they were based on physician-based reports (with the KS and HSS) than when they were reported by patients (with the WOMAC and SF-36).

However, overall, the scientific quality of the current evidence is too weak to support specific recommendations about which patients are best served by this procedure. Only a handful of studies employed any form of multivariate analysis. The outcomes of orthopaedic surgery, like those of most other interventions, are the results of interactions between the treatments and the characteristics of the patients. Real understanding will come about only when the analytic techniques can address both sets of variables simultaneously.

Because our search strategy was conditioned on the presence of data regarding functional activity, our study offers a limited view of revision rates. Several larger studies based on registry data suggested that the revision rates of total knee arthroplasty are generally low. Furnes et al. found a five-year prosthetic survival rate of 95% to 99% following 7174 primary total knee replacements²⁸. Coyte et al. found a 7% revision rate over a seven-year period following 18,530 knee replacements²⁷. Robertsson et al. reported a cumulative revision rate of 25% in a series of 41,223 knees followed for eighteen years, but they noted that the rate following newer procedures decreased by 7% annually between 1976 and 1997³⁰.

Although there is recurring evidence that total knee arthroplasties improve function and alleviate pain, much less is known about what types of patients are most likely to benefit from this surgery. There is no evidence that age, gender, or obesity are strong predictors of functional outcomes, but the extremes of age and obesity have not been actively studied. Patients with rheumatoid arthritis show more improvement than do those with osteoarthritis, but this finding may be related to their poorer baseline functional scores (or other factors) creating the potential for more improvement. The role of other potential predictors of functional outcome, such as preoperative bodily pain or joint pain, comorbidities, and type of prosthesis, could not be determined. As the pressure for more informed decisions grows, this type of information will be greatly needed³¹. The search for evidence about the indications for total knee arthroplasty was frustrating. The literature is replete with articles that compare different procedures and prostheses, but relatively little attention has been paid to the characteristics of the patients. Typically, authors describe the sample under study and then ignore these characteristics in their analyses.

Because orthopaedic research will likely rely heavily on observational studies instead of randomized controlled trials, it will be important to use more robust methods of study design and analysis. Future observational studies need to be deliberately planned with consistent, prospective data collection with use of standardized tools. Ideally, the data should be collected by a consistent group of individuals, even across different clinicians. All patients enrolled should be followed, and the analysis must address the effects of attrition. Particular attention must be paid to ensuring that the cohorts remain intact. Greater efforts must be made to collect outcomes information on all participants, not just those who return for follow-up visits. The analyses in such studies need to be done with sophisticated statistical methods with which the investigators can examine the effects of patient characteristics on the outcomes of interest.

Appendix

A table presenting details of all sixty-two studies is available with the electronic versions of this article, on our web site at (go to the article citation and click on "Supplementary Material") and on our quarterly CD-ROM (call our subscription department, at 781-449-9780, to order the CD-ROM). ?

Acknowledgements

Note: William W. Cross III, BA; Roderick M. MacDonald, MS; and Indulis Rutks, BS, contributed substantially to the preparation of the final report for this project. The authors thank the individuals who worked on the abstractions, including Tyler Bailey; Jesse Botker; Kevin Bozic, MD; Kevin Broder; Gideon Burstein, MD; Jason J. Caron; Stephanie Cintora; Todd Gengerke; Brad Hilger; Richard Iorio, MD; Craig Israelite, MD; William Macaulay, MD; Charles Nelson, MD; and Alexander W. Stricker III.

References

Orthopedic Network News. 2002 hip and knee implant review. 2002. CMS MedPar .
www.orthopedicnetworknews.com

Deyo RA, Nachemson A, Mirza SK. Spinal-fusion surgery- the case for restraint. N Engl J Med.2004;350: 722-6.350722 2004 [PubMed][CrossRef]

Alicea J. Scoring systems and their validation for the arthritic knee. In: Insall JN, Churchill SN, editors. Surgery of the knee. 3rd ed. New York: Livingstone; 2001. p 1507-15.1507 2001

Insall JN, Dorr LD, Scott RD, Scott WN. Rationale of the Knee Society clinical rating system. Clin Orthop Relat Res.1989;248: 13-4.24813 1989

Bellamy N, Buchanan WW, Goldsmith CH, Campbell J, Stitt LW. Validation study of WOMAC: a health status instrument for measuring clinically important patient relevant outcomes to antirheumatic drug therapy in patients with osteoarthritis of the hip or knee. J Rheumatol.1988;15: 1833-40.151833 1988

Stewart AL, Hays R, Ware JE Jr. The MOS short-form general health survey. Reliability and validity in a patient population. Med Care.1988;26: 724-35.26724 1988 [PubMed][CrossRef]

Ware JE Jr, Snow KK, Kosinski M, Gandek B. SF-36 health survey. Manual and interpretation guide. Boston: The Health Institute, New England Medical Center; 1993. 1993

Callahan CM, Drake BG, Heck DA, Dittus RS. Patient outcomes following tricompartmental total knee replacement. A meta-analysis. JAMA.1994;271: 1349-57.2711349 1994 [PubMed][CrossRef]

Tierney WM, Fitzgerald JF, Heck DA, Kennedy JM, Katz BP, Melfi CA, Dittus RS, Allen DI, Freund DA. Tricompartmental knee replacement. A comparison of orthopaedic surgeons' self reported performance rates with surgical indications, contraindications, and expected outcomes. Knee Replacement Patient Outcomes Research Team. Clin Orthop Relat Res.1994;305: 209-17.305209 1994 [PubMed]

Wright JG, Coyte P, Hawker G, Bombardier C, Cooke D, Heck D, Dittus R, Freund D. Variation in orthopedic surgeons' perceptions of the indications for and outcomes of knee replacement. CMAJ.1995;152: 687-97.152687 1995 [PubMed]

Mancuso CA, Ranawat CS, Esdaile JM, Johanson NA, Charlson ME. Indications for total hip and total knee arthroplasties. Results of orthopaedic surveys. J Arthroplasty.1996;11: 34-46.1134 1996 [PubMed][CrossRef]

Coyte PC, Hawker G, Croxford R, Attard C, Wright JG. Variation in rheumatologists' and family physicians' perceptions of the indications for and outcomes of knee replacement surgery. J Rheumatol.1996;23: 730-8.23730 1996

Wright JG, Hawker GA, Bombardier C, Croxford R, Dittus RS, Freund DA, Coyte PC. Physician enthusiasm as an explanation for area variation in the utilization of knee replacement surgery. Med Care.1999;37: 946-56.37946 1999 [PubMed][CrossRef]

Mamlin LA, Melfi CA, Parchman ML, Gutierrez B, Allen DI, Katz BP, Dittus RS, Heck DA, Freund DA. Management of osteoarthritis of the knee by primary care physicians. Arch Fam Med.1998;7: 563-7.7563 1998 [CrossRef]

Cohen J. Statistical power analysis for the behavioral sciences. 2nd ed. Hillsdale, NJ: Lawrence Erbaum; 1988. 1988

Borenstein M, Rothstein H. Comprehensive meta-analysis: a computer program for research synthesis. Englewood, NJ: Biostat, Inc.; 1999. 1999

Ewald FC, Wright RJ, Poss R, Thomas WH, Mason MD, Sledge CB. Kinematic total knee arthroplasty: a 10- to 14-year prospective follow-up review. J Arthroplasty.1999;14: 473-80.14473 1999 [PubMed][CrossRef]

Gill GS, Joshi AB. Long-term results of cemented, posterior cruciate ligament-retaining total knee arthroplasty in osteoarthritis. Am J Knee Surg.2001;14: 209-14.14209 2001 [PubMed]

Miyasaka KC, Ranawat CS, Mullaji A. 10- to 20-year follow-up of total knee arthroplasty for valgus deformities. Clin Orthop Relat Res.1997;345: 29-37.34529 1997 [PubMed]

Stickles B, Phillips L, Brox W, Owens B, Lanzer WL. Defining the relationship between obesity and total joint arthroplasty. Obes Res.2001;9: 219-23.9219 2001 [PubMed][CrossRef]

Jones CA, Voaklander DC, Johnston DW, Suarez-Almazor ME. The effect of age on pain, function, and quality of life after total hip and knee arthroplasty. Arch Intern Med.2001;161: 454-60.161454 2001 [PubMed][CrossRef]

Regner L, Carlsson L, Karrholm J, Herberts P. Clinical and radiologic survivorship of cementless tibial components fixed with finned polyethylene pegs. J Arthroplasty.1997;12: 751-8.12751 1997 [PubMed][CrossRef]

Hawker G, Wright J, Coyte P, Paul J, Dittus R, Croxford R, Katz B, Bombardier C, Heck D, Freund D. Health-related quality of life after knee replacement. J Bone Joint Surg Am.1998;80: 163-73.80163 1998 [PubMed]

Jones RE, Skedros JG, Chan AJ, Beauchamp DH, Harkins PC. Total knee arthroplasty using the S-ROM mobile-bearing hinge prosthesis. J Arthroplasty.2001;16: 279-87.16279 2001 [PubMed][CrossRef]

Deshmukh RG, Hayes JH, Pinder IM. Does body weight influence outcome after total knee arthroplasty? A 1-year analysis. J Arthroplasty.2002;17: 315-9.17315 2002 [PubMed][CrossRef]

Fortin PR, Clarke AE, Joseph L, Liang MH, Tanzer M, Ferland D, Phillips C, Partridge AJ, Belisle P, Fossel AH, Mahomed N, Sledge CB, Katz JN. Outcomes of total hip and knee replacement: preoperative functional status predicts outcomes at six months after surgery. Arthritis Rheum.1999;42: 1722-8.421722 1999 [PubMed][CrossRef]

Konig A, Kirschner S, Walther M, Eisert M, Eulert J. Hybrid total knee arthroplasty. Arch Orthop Trauma Surg.1998;118: 66-9.11866 1998 [CrossRef]

Furnes O, Espehaug B, Lie SA, Vollset SE, Engesaeter LB, Havelin LI. Early failures among 7,174 primary total knee replacements: a follow-up study from the Norwegian Arthroplasty Register 1994-2000. Acta Orthop Scand.2002;73: 117-29.73117 2002 [PubMed][CrossRef]

Coyte PC, Hawker G, Croxford R, Wright JG. Rates of revision knee replacement in Ontario, Canada. J Bone Joint Surg Am.1999;81: 773-82.81773 1999

Robertsson O, Knutson K, Lewold S, Lidgren L. The Swedish Knee Arthroplasty Register 1975-1997: an update with special emphasis on 41,223 knees operated on in 1988-1997. Acta Orthop Scand.2001;72: 503-13.72503 2001 [CrossRef]

Norton EC, Garfinkel SA, McQuay LJ, Heck DA, Wright JG, Dittus R, Lubitz RM. The effect of hospital volume on the in-hospital complication rate in knee replacement patients. Health Serv Res.1998;33: 1191-210.331191 1998

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Robert L. Kane, Khaled J. Saleh, Timothy J. Wilt, Boris Bershadsky; The Functional Outcomes of Total Knee Arthroplasty. The Journal of Bone & Joint Surgery. 2005 Aug;87(8):1719-1724.

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