Total knee replacement is one of the most successful surgical procedures in Orthopaedics. However, 10-20% of the patients are still dissatisfied with the results of the surgery. In general, the evaluation of postoperative functional outcomes are usually measured by self-report questionnaires, such as the Western Ontario and Mcmaster Universities osteoarthritic Index (WOMAC) and the Short Form-36 health survey (SF-36). Another method to evaluate functional outcome of the patients is to use the performance-based tests such as the two-minute walk test, but there is still little information regarding its use for evaluating functional recovery in patients receiving total knee arthroplasty. The objectives this study are: 1) to assess the relationship between self-report questionnaires and performance-based tests among patients scheduling for TKA; and 2) to identify clinical variables that are associated with pre- and postoperative functional performance of the patients.

Population

Patients who receive uncomplicated total knee replacement by a single surgeon

Brief Title

Functional Recovery After Total Knee Arthroplasty

Official Title

The Evaluation of Short-term Functional Recovery of Total Knee Arthroplasty Patients

Brief Summary

Total knee replacement is one of the most successful surgical procedures in Orthopaedics.<br /> However, 10-20% of the patients are still dissatisfied with the results of the surgery. In<br /> general, the evaluation of postoperative functional outcomes are usually measured by<br /> self-report questionnaires, such as the Western Ontario and Mcmaster Universities<br /> osteoarthritic Index (WOMAC) and the Short Form-36 health survey (SF-36). Another method to<br /> evaluate functional outcome of the patients is to use the performance-based tests such as the<br /> two-minute walk test, but there is still little information regarding its use for evaluating<br /> functional recovery in patients receiving total knee arthroplasty.<br /><br /> The objectives this study are: 1) to assess the relationship between self-report<br /> questionnaires and performance-based tests among patients scheduling for TKA; and 2) to<br /> identify clinical variables that are associated with pre- and postoperative functional<br /> performance of the patients.

Detailed Description

Osteoarthritis (OA) of the knee is one of the most prevalent age-related musculoskeletal
conditions, resulting in significant impairment in patients' abilities to perform activities
and adversely impacting their quality of life. The level of impairment in patients with knee
OA can be measured using validated self-report questionnaires, such as the disease-specific
Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the generic
Medical Outcomes Study Short Form-36 (SF-36). Self-report questionnaires have been
recommended by some investigators for their high internal consistency and ease of
administration. Another method to evaluate physical function in patients with knee OA is to
use performance-based tests. These tests are tools that assess patients' ability to execute a
task in a standardized environment, and include the 2-minute walk test (2MWT) and the timed
get-up-and-go test (TUG).

Among all the self-reported questionnaires for knee OA, the WOMAC is one of the most commonly
used for baseline assessment and for measurement of treatment outcome, and has been validated
for patients undergoing total knee arthroplasty (TKA). Although the WOMAC provides
information on how individuals perceive their physical function in their own environment, it
does not describe their ability to perform a specific task or action. In addition, some
investigators showed that scores from self-report questionnaires before and after
arthroplasty can overestimate patients' actual functional capacity. For example, Parent et al
demonstrated that total knee arthroplasty patients had a dramatic improvement at 2 months as
assessed by the WOMAC function subscale, however there were no significant changes when
measured with performance-based tests assessing gait speed and stair ascent duration.
Therefore, clinicians should be cautious when interpreting findings from studies that provide
only self-report questionnaire scores. Given that self-report questionnaires may
over-estimate functional status after joint replacement, some authors advocate
performance-based tests as measures of outcome, and recommend their use during the
preoperative period as baseline measurements followed by subsequent comparison with
postoperative measurements.

The objectives of this study are: 1) to assess the relationship between self-reported
questionnaires (WOMAC and SF-36) and performance-based tests (2MWT, TUG) among patients
scheduling for TKA; and 2) to identify clinical variables that are associated with pre- and
post-operative performance of the 2MWT and TUG. Our hypothesis is that correlations between
self-report questionnaires and performance-based tests would be low to moderate, and thus
these two types of measurements evaluate distinct domains of functional status in patients
undergoing TKA.