Effect of Age and Sex on Psychological Readiness and Patient-Reported Outcomes 6 Months After Primary ACL Reconstruction

Abstract

Background: Successful return to sport after anterior cruciate ligament (ACL) reconstruction (ACLR) can be affected by a patient’s physical and psychological state throughout the rehabilitation process. Purpose: To prospectively compare differences in patients at 6 months after primary ACLR with the ACL–Return to Sport after Injury (ACL-RSI), International Knee Documentation Committee (IKDC) or pediatric (Pedi)-IKDC, Hospital for Special Surgery Pediatric Functional Activity Brief Scale (Pedi-FABS), and Patient-Reported Outcomes Measurement Information System–Psychological Stress Experiences (PROMIS-PSE) scores. Study Design: Prospective cohort study; Level of evidence, 2. Methods: Patients enrolled were 8 to 35 years old who underwent primary ACLR and had their 6-month follow-up appointments between December 2018 and March 2020. Patients were divided into 3 age groups as follows: (1) preadolescents (10-14 years); (2) adolescents (15-18 years); and (3) adults (>18 years). Outcomes on the ACL-RSI, IKDC/Pedi-IKDC, Pedi-FABS, and PROMIS-PSE were compared according to age group, graft type (hamstring, patellar tendon, quadriceps, or iliotibial band autograft), and sex. Results: A total of 176 patients (69 male, 107 female), with a mean age of 17.1 ± 3.1 years were included in the study. The mean ACL-RSI scores were significantly different among age groups (preadolescents, 75 ± 18.9; adolescents, 61.5 ± 20.4; and adults, 52.5 ± 19.8 [ P < .001]) and graft types ( P = .024). The IKDC and PROMIS-PSE scores were also significantly different among age groups ( P < .001 and P = .044, respectively) and graft types ( P = .034 and P < .001, respectively), with the iliotibial graft and the younger age group performing the best. There was no significant difference in the Pedi-FABS either by age group ( P = .127) or graft type ( P = .198). Female patients had lower ACL-RSI scores and higher (worse) scores on PROMIS-PSE than their male counterparts ( P = .019 and P < .001, respectively), with no sex-based differences on IKDC or Pedi-FABS scores. The ACL-RSI and IKDC were positively correlated (Spearman r = 0.57; P < .001), while the ACL-RSI and PROMIS-PSE were negatively correlated (Pearson r = –0.34; P < .001). Conclusion: This study suggests that psychological profiles and subjective perceptions of knee function 6 months after ACLR may vary in patients of different ages and between the sexes. Preadolescent patients had better scores on a majority of patient-reported outcomes compared with adolescent and adult patients.