Developing a Framework for Ankle Function: A Delphi Study

Context:

Addressing clinical outcomes is paramount to providing effective health care, yet there is no consensus regarding the appropriate outcomes to address after ankle injuries. Compounding the problem is the repetitive nature of lateral ankle sprains, referred to as functional (FAI) or chronic (CAI) ankle instability. Although they are commonly used terms in practice and research, FAI and CAI are inconsistently defined and assessed.

Objective:

To establish definitions of a healthy/normal/noninjured ankle, FAI, and CAI, as well as their characteristics and assessment techniques.

Design:

Delphi study.

Setting:

Telephone interviews and electronic surveys.

Patients or Other Participants:

Sixteen experts representing the fields of ankle function and treatment, ankle research, and outcomes assessment and research were selected as panelists.

Data Collection and Analysis:

A telephone interview produced feedback regarding the definition of, functional characteristics of, and assessment techniques for a healthy/normal/noninjured ankle, an unhealthy/acutely injured ankle, and FAI/CAI. Those data were compiled, reduced, and returned through electronic surveys and were either included by reaching consensus (80% agreement) or excluded.

Results:

The definitions of a healthy/normal/noninjured ankle and FAI reached consensus. Experts did not agree on a definition of CAI. Eleven functional characteristics of a healthy/normal/noninjured ankle, 32 functional characteristics of an unhealthy/acutely injured ankle, and 13 characteristics of FAI were agreed upon.

Conclusions:

Although a consensus was reached regarding the definitions and functional characteristics of a healthy/normal/noninjured ankle and FAI, the experts could only agree on 1 characteristic to include in the FAI definition. Several experts did, however, provide additional comments that reinforced the differences in the interpretation of those concepts. Although the experts could not agree on the definition of CAI, its characteristics, or the preferred use of the terms FAI and CAI, our findings provide progress toward establishing consistency in those concepts.Key Words: outcomes, ankle sprains, ankle instability

Key Points

• A working definition of a healthy/noninjured ankle was established, along with the functional characteristics of and assessment techniques for healthy and unhealthy ankles.
• Although a consensus was reached regarding the definition of functional ankle instability, disagreements emerged in the experts'' comments. The definition that achieved consensus is very similar to the original Freeman definition.
• Consensus was not reached regarding the definition of chronic ankle instability.
• Future researchers should compare the experts'' responses with feedback from patients who sustained ankle injuries and with ankle-outcome instruments.

The National Athletic Trainers'' Association Research & Education Foundation has identified outcomes assessment as a professional priority.¹ There is no more vivid example of the barriers to the consistent assessment of outcomes than in the treatment of ankle and foot injuries. Specifically, lateral ankle sprains (LAS) continue to represent the single most common athletic injury² and have the highest reinjury rate among all injuries,^2–4 yet outcomes that substantiate their treatment are limited. Further complicating outcomes assessment after LAS is the repetitive nature of ankle sprains, which has led to the identification of a phenomenon called chronic or functionalankle instability (CAI or FAI, respectively).^5–7 Although a common entity in practice and research, FAI is inconsistently defined and assessed.^8–10 Despite widespread support for its existence, there is currently no consensus regarding the definition of FAI^8–10 or the characteristics of those who have it. Researchers classify the existence of FAI inconsistently, and clinicians diagnose it arbitrarily. To substantiate the existence and relevance of any injury or condition, it must be definable and have a measurable effect on function. Neither of those is true regarding FAI, which has resulted in discrepancies in the research, making cross-study comparisons impossible, and the true effect of FAI remains largely unknown. The lack of standard outcomes and the inconsistencies in the identification of repetitive LAS have further complicated the reporting of ankle-injury outcomes. Therefore, athletic trainers are unable to address 1 of the most important issues identified in their profession (ie, outcomes) for the most common injury, LAS, of the patients in their care.Following the model from the World Health Organization (WHO),¹¹ the first steps toward outcomes assessment after LAS are to (1) develop a framework of a healthy/normal/noninjured ankle, (2) establish a clear definition for the recurring ankle-sprain phenomenon, or FAI, and (3) identify the functional outcomes that should be assessed after LAS.¹¹ A common approach to this type of problem is to gather input from a panel of content experts in an effort to establish consensus regarding a certain topic. Therefore, we used the Delphi method to determine the definitions of a healthy/normal/noninjured ankle, FAI, and CAI, along with their characteristics and assessment techniques.