Isokinetic Functional Capacity Evaluation Overview

A Isokinetic Functional Capacity Evaluation (a derivative of functional capacity evaluation) is an objective comprehensive physical test of isolated joint and/or combined functional performance. They are used commonly to determine ability for work, activities of daily living, or leisure activities.

Functional capacity evaluation (FCE) was identified in America in the 1980s and was a response to demands by workers’ compensation systems. They required specific information about employee functional abilities and limitations. In essence this was to offer objective assessment of several key areas:

Pre-employment:

  • Job placement decisions
  • Ability (often called disability) evaluation

Post-employment:

  • Return to work
  • Determination of how non-work-related illness and injuries impact work performance
  • Determination of functioning in non-occupational setting
  • Disability/ability evaluation
  • Intervention and treatment planning
  • Case management and case closure

(American Physical Therapy Association. Occupational health guidelines: guidelines for evaluating functional capacity. BOD 11-97-16-53, 1997. Revised 1998, 2008.)

Return-to-work decisions had historically been based upon diagnoses and prognoses of physicians/occupational health professionals. These did not include objective measurements of functional abilities and did not match the physical demands of the employment. Physio/Physical therapists, with training in assessing physical capabilities, began to develop functional capacity tests for comparison to the physical demands of jobs and occupations.

Many versions of these tests were developed and a burgeoning industry developed offering evaluations with various biases. Methods included different forms of objective testing with isokinetic evaluation offering the strictest objective measurements.

Isokinetic machines were in a unique position to offer very accurate, reliable and reproducible data. Having been used in medicine and research since the end of the 1960’s the machines were readily available and had already been scrutinized by the research community as the most accurate way of assessing human musculo-skeletal performance.

Initially the evaluations examined the ability of an employee to perform physical job conditions (matched to the job) as described by the Selected Characteristics of Occupations (as Defined in the Revised Dictionary of Occupational Titles. U.S. Department of Labor. National Technical Information Service, PB94-116282, 1993) and The Revised Handbook for Analyzing Jobs. (US Department of Labor Employment and Training Administration. 1991).  Functional Evaluation, combined with diagnoses and prognoses by physical therapists emerged as both a valid and effective tool to support safe return to work, activities of daily living or leisure activities after an injury or illness (APTA 2008).

There are two types of functional capacity evaluations (as defined by the APTA 2008):

General Purpose FCE.

‘The evaluation protocol consists of standardized tests and measures that are applied to all evaluees. This type is appropriate when a targeted job does not exist, or functional job requirements have not yet been determined. The results from this type of FCE may be used to evaluate an evaluee’s compatibility with specific job or occupational demands when more information or options become available for consideration.’

Job-specific FCE.

‘The evaluation protocol is designed with emphasis on content validity to measure an evaluee’s ability to perform the physical demands of a specific, identified job. This type of FCE may include participation in representative work samples in a clinic or monitoring the evaluee while performing critical job tasks at the work-site to determine the evaluee’s ability to safely perform the required work tasks and to determine whether there are participation restrictions.’

A functional capacity evaluation (FCE) normally comprises;

Examination.

  • A comprehensive screening and specific testing process leading to diagnostic classification or, as appropriate, to a referral to another practitioner. Examination has three components: history, systems review, and tests/measures.

Evaluation.

  • A dynamic process in which the physio/physical therapist makes clinical judgments based on data gathered during the examination.
  • Overall the evaluation normally focuses on key areas(the list below is for illustration only from APTA 2008):

Ability. A present competence to perform an observable behavior or a behavior which results in an observable product.

Activity. An activity is the execution of a task or action by an individual.

Activity limitation. Activity limitations are difficulties an individual may have in executing activities.

Capacity. The highest probable level of functioning of an individual in a given domain at a point in time.

Impairments. Impairments are problems in body function or structure such as a significant deviation or loss.

Job analysis. The process of analyzing job duties and responsibilities to quantify functional job demands or performance expectations.

Job description. A general statement of job duties and responsibilities.

Participation Restrictions. Participation restrictions are problems an individual may experience during involvement in life situations.

Performance. What an individual does in his or her current environment. Performance is affected by a number of factors including behavioural attitudes, injury, pain and environmental and social stressors.

All reports offer high levels of validity (they contain what is technically known as content validity). This is demonstrated by the data showing that the content of a selection procedure is representative of important aspects of performance on the job. In work-injury management, FCEs are often used in case closure and may end in court decisions. Therefore, it is critical that FCEs are reliable and valid. For FCE tests to be reliable and valid, specific criteria must be met with regards to reliability, reproducibility and validity of the test. The factors involved in each of these areas are described in the FCE reliability and validity page.