Do Sociodemographic Factors Influence Patient-reported Outcomes After Transfemoral Osseointegration Surgery? A Secondary Analysis of the Transfemoral Amputation Osseointegration Study

Background – Osseointegration is a surgical procedure that enables the direct attachment of a prosthesis to the residual long bone after amputation in individuals who have not tolerated traditional prostheses. After osseointegration, military service members demonstrate improved functionality; however, the association between sociodemographic factors and patient-reported outcome measure (PROM) scores is less clear. Sociodemographic factors, such as marital status, educational attainment, and physical location, influence both physical and mental health.Questions/purposes – (1) Are social and demographic characteristics, including marital status, education, and income, associated with differences in PROM scores after transfemoral osseointegration? (2) Is the location of rehabilitation (integrated amputee care centers at military treatment facilities or private clinics) associated with differences in PROM scores after these procedures?Methods – We performed a secondary analysis of the Walter Reed National Military Medical Center Transfemoral Amputee Osseointegration Study using sociodemographic factors and PROMs at the preoperative baseline and 3, 6, 12, and 24 months after two-stage osseointegration surgery. Individuals who had a transfemoral amputation and had issues with a traditional socket-based prosthesis were eligible for this prospective therapeutic study. Thirty-seven of 41 enrolled participants completed the study through the 24-month time point, with one patient receiving bilateral osseointegration at separate time points, resulting in 38 patients being included in the analyses. The mean ± SD patient age was 38 ± 10 years, and 92% (35 of 38) of participants were male, 76% (29) were married, 53% (20) had a K-12 education, 89% (34) completed rehabilitation at an integrative amputee care center, and the median (IQR) patient income was USD 41, 961 (9762). Student t-tests for normal data were conducted to evaluate the relationships between sociodemographic factors (marital status, education, location of rehabilitation) and PROM scores. Mann-Whitney U tests were used to evaluate the relationships between sociodemographic factors (marital status, education, and location of rehabilitation) and PROM scores, as measured by the Questionnaire for Persons with Transfemoral Amputations (Q-TFA) and the Orthotics and Prosthetics Users Survey (OPUS), for non-normal data. Linear mixed-effects models with post hoc Tukey honestly significant difference tests were used to analyze income and PROM scores. The Q-TFA is a validated survey for patients with amputations. It provides four measurements: the global score, prosthetic use score, prosthetic mobility score, and the problem score, all with values from 0 to 100, with higher scores indicating a better outcome, except for the problem score, where a higher value means more problems. The anchor-based minimum clinically important difference (MCID) for the Q-TFA for this population is 17 points, which 82% (31 of 38) of participants achieved. The OPUS Health Quality of Life survey was used in this study, a validated clinical tool designed for patients using orthotics or prosthetics, with scores ranging from 0 to 92, where a higher score indicates a better outcome. A novel anchor-based MCID for the OPUS questionnaire is presented in this work.Results – In presenting a new MCID for the OPUS quality-of-life measure for our cohort, we found the value to be 16, which was met by a total of 14 patients at the 12-month follow-up. Participants who were married had higher mean ± SD quality-of-life scores at baseline (married 67 ± 10 versus single 48 ± 9, mean difference 19 [95% confidence interval (CI) 12 to 26]; p < 0.001) and at 3 months (married 71 ± 11 versus single 53 ± 25, mean difference 18 [95% CI 6 to 30]; p = 0.04). Participants with less education demonstrated higher Q-TFA global scores after surgery (K-12 at 3 months 63 ± 24 versus university or higher at 3 months 41 ± 23, mean difference 22 [95% CI 14 to 30], p = 0.007; K-12 at 6 months 67 ± 24 versus university or higher at 6 months 48 ± 24, mean difference 19 [95% CI 11 to 27], p = 0.02; K-12 at 12 months 73 ± 20 versus university or higher at 12 months 57 ± 25, mean difference 16 [95% CI 9 to 23], p = 0.04; K-12 at 24 months 82 ± 13 versus university or higher at 24 months 63 ± 23, mean difference 19 [95% CI 13 to 25], p = 0.005). Participants with less education also demonstrated lower median (range) Q-TFA problem scores (K-12 at baseline 38 [17 to 66] versus university or higher at baseline 52 [19 to 76], p = 0.03; K-12 at 3 months 13 [1 to 51] versus university or higher at 3 months 25 [3 to 79], p = 0.02; K-12 at 6 months 10 [2 to 66] versus university or higher 26 [0 to 85], p = 0.02; K-12 at 12 months 10 [2 to 49] versus university or higher at 12 months 28 [2 to 57], p = 0.02; K-12 at 24 months 9 [2 to 30] versus university or higher at 24 months 21 [0 to 70], p = 0.009). Income was not associated with better PROM scores. Location of rehabilitation was associated with improved PROM scores. Patients who were rehabilitated at a nonmilitary facility (integrated amputee care center) had more prosthetic use at the 3-month follow-up versus a private facility (median [range] score 7 [0 to 100] versus 100 [44 to 100], p = 0.02).Conclusion – Our findings do not align with the current research on sociodemographic factors and PROMs, which may be due to a myriad of reasons. To better support their patients at the individual level, surgeons and the patient care team may consider the sociodemographic status of their patients and develop a more tailored approach to improve outcomes and identify any barriers to success. The underlying mechanisms explaining why specific demographics, such as lower educational attainment, have better outcomes need to be better understood to provide the best care for patients.Level of Evidence – Level III, therapeutic study.