Is Self-reported Return to Duty an Adequate Indicator of Return to Sport and/or Return to Function in Military Patients?

Background In the military, return-to-duty status has commonly been used as a functional outcome measure after orthopaedic surgery. This is sometimes regarded similarly to return to sports or as an indicator of return to full function. However, there is variability in how return-to-duty data are reported in clinical research studies, and it is unclear whether return-to-duty status alone can be used as a surrogate for return to sport or whether it is a useful marker for return to full function. Questions/purposes (1) What proportion of military patients who reported return to duty also returned to athletic participation as defined by self-reported level of physical activity? (2) What proportion of military patients who reported return to duty reported other indicators of decreased function (such as nondeployability, change in work type or level, or medical evaluation board)? Methods Preoperative and postoperative self-reported physical profile status (mandated physical limitation), physical activity status, work status, deployment status, military occupation specialty changes, and medical evaluation board status were retrospectively reviewed for all active-duty soldiers who underwent orthopaedic surgery at Madigan Army Medical Center, Joint Base Lewis-McChord from February 2017 to October 2018. Survey data were collected on patients preoperatively and 6, 12, and 24 months postoperatively in all subspecialty and general orthopaedic clinics. Patients were considered potentially eligible if they were on active-duty status at the time of their surgery and consented to the survey (1319 patients). A total of 89% (1175) were excluded since they did not have survey data at the 1 year mark. Of the remaining 144 patients, 9% (13) were excluded due to the same patient having undergone multiple procedures, and 2% (3) were excluded for incomplete data. This left 10% (128) of the original group available for analysis. Ninety-eight patients reported not having a physical profile at their latest postoperative visit; however, 14 of these patients also stated they were retired from the military, leaving 84 patients in the return-to-duty group. Self-reported "full-time duty with no restrictions" was originally used as the indicator for return to duty; however, the authors felt this to be too vague and instead used soldiers' self-reported profile status as a more specific indicator of return to duty. Mean length of follow-up was 13 ± 3 months. Eighty-three percent (70 of 84) of patients were men. Mean age at the preoperative visit was 35 ± 8 years. The most common surgery types were sports shoulder (n = 22) and sports knee (n = 14). The subgroups were too small to analyze by orthopaedic procedure. Based on active-duty status and requirements of the military profession, all patients were considered physically active before their injury or surgery. Return to sport was determined by asking patients how their level of physical activity compared with their level before their injury (higher, same, or lower). We identified the number of other indicators that may suggest decreased function by investigating change in work type/level, self-reported nondeployability, or medical evaluation board. This was performed with a simple survey. Results Of the 84 patients reporting return to duty at the final follow-up, 67% (56) reported an overall lower level of physical activity. Twenty-seven percent (23) reported not returning to the same work level, 32% (27) reported being nondeployable, 23% (19) reported undergoing a medical evaluation board (evaluation for medical separation from the military), and 11% (9) reported a change in military occupation specialty (change of job description). Conclusion Return to duty is commonly reported in military orthopaedics to describe postoperative functional outcome. Although self-reported return to duty may have value for military study populations, based on the findings of this investigation, surgeons should not consider return to duty a marker of return to sport or return to full function. However, further investigation is required to see to what degree this general conclusion applies to the various orthopaedic subspecialties and to ascertain how self-reported return to duty compares with specific outcome measures used for particular procedures and subspecialties. Level of evidence Level IV, therapeutic study.