Development and validation of a novel method for assessing physical activity profiles after anterior cruciate ligament reconstruction: The Sports and Physical Activity scale

Objectives: To describe and evaluate the preliminary validity of a novel scoring system for assessing the physical activity of patients after anterior cruciate ligament (ACL) reconstruction. Methods: The Sports and Physical Activity (SPA) scale consists of thirty options of sports and physical activities, followed by four frequency options for each option selected. Factors used to develop the scoring system were frequency of participation and intensity of the sports or physical activities. Possible scores ranged from a low of 0 to a high of 24. The scale was assessed for validity and responsiveness. Results: The study cohort included 418 primary ACL reconstructed patients 2 years after surgery, and a subgroup of 183 patient 5 years after surgery. The mean and median SPA scores for the cohort were 12.35 (+/- 6.95) and 12, respectively. There was no statistically significant difference between the scores of men and women (U = 21,541.0, p = 0.921). The SPA scale had a small but statistically significant inverse correlation with age (r(s) = -0.2, p = <0.001), indicating divergent validity. Patients who had returned to sport had a statistically significantly higher score (U = 21593.5, p = <0.001), and there was a statistically significant difference between scores of the three current sports status groups (H = 19.99, p value = <0.001) indicating convergent validity. Construct validity was indicated with a statistically significant correlation with the Marx scale (r(s) = 0.422, p value= <0.001). In a subgroup (n = 183) of the patient sample, comparison between scores at 2-years (13.27 +/- 7.02) and 5-years (12.11 +/- 7.88) found a statistically significant decline (p= <0.001). However, this decline was smaller than the decline seen in the Marx score between 2 and 5 years (11.11 +/- 4.07 and 9.30 +/- 4.52 p= <0.001). Conclusion: Preliminary validity was found for the SPA scale. Women and men were found to be participating in a similar amount of activity 2 years post ACL reconstruction, despite return to sport differences between men and women being well documented. The scores of the SPA scale showed a statistically significant decrease over time with a negligible effect size.