The LEFT was initially designed to assess the injured athlete's ability to perform sport‐specific movement patterns. The LEFT test consists of eight agility drills (forward run, backward run, side shuffle, carioca, figure 8 run, 45º cuts, 90º cuts) performed on a diamond shaped course (Figure 1).

Contents 5.1 Reliability. 5.2 Validity. 5.3 Responsiveness. 5.4 Miscellaneous.

The LEFS scores demonstrated excellent test-retest reliability (intraclass correlation coefficients ranging between 0.85 and 0.99) and demonstrated the expected relationships with measures assessing similar constructs (Pearson correlation coefficient values of greater than 0.7).

The Lower Extremity Functional Scale (LEFS) is a questionnaire containing 20 questions about a person's ability to perform everyday tasks. The LEFS can be used by clinicians as a measure of patients' initial function, ongoing progress and outcome, as well as to set functional goals.

The LEFS can be used to evaluate the functional impairment of a patient with a disorder of one or both lower extremities. It can be used to monitor the patient over time and to evaluate the effectiveness of an intervention. The columns on the scale are summed to get a total score.

They found a mean LEFS score of 71, indicating a good result of their treatment. When less than 15% of the individuals have the minimum score, no floor effect is present, and when less than 15% reach the maximum score, there is no ceiling effect (McHorney and Tarlov 1995).

The primary limitation of this measure is the variability when the last LEFS was captured over the 1 year postoperative period, as this is likely to increase as patients complete rehabilitation over time. In our study, the average time to postoperative LEFS was 110 days, but ranged from 60 to 361 days.