Sex Differences in Patient-Reported Outcomes After Anterior Cruciate Ligament Reconstruction: Data From the Swedish Knee Ligament Register.

Research output: Contribution to journalArticle


BACKGROUND: Female gender is a risk factor for sustaining anterior cruciate ligament (ACL) injury. However, little is known about possible sex differences in patients with ACL injury/reconstruction. PURPOSE: To study sex differences in patient-reported outcomes before and at 1 and 2 years after ACL reconstruction and to present reference values. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Between 2005 and 2008, 10 164 patients (mean age, 27 years; SD, 9.8; 42% females) with primary ACL reconstruction were registered in the Swedish national knee ligament register. There were 4438 (44%) of these patients (42% females) who had completed the knee-specific questionnaire, Knee injury and Osteoarthritis Outcome Score (KOOS), and 5255 (52%) who had completed the generic score of health status, EQ-5D, before surgery and were included in this study. Independent t tests were used to study sex differences in KOOS and EQ-5D preoperatively, 1 and 2 years postoperatively, and over time. RESULTS: Preoperatively, female patients reported worse scores than male patients in 4 KOOS subscales (pain, symptoms, sport/recreation, quality of life) and EQ-5D, with the largest difference seen in KOOS sport/recreation (mean difference, 4.7; 95% confidence interval [CI], 3.0-6.3). At 1 year postoperatively, female patients reported worse scores than male patients in KOOS pain (mean difference, 1.4; 95% CI, 0.4-2.4) and KOOS sport/recreation (mean difference, 2.7; 95% CI, 0.9-4.4) and at 2 years postoperatively in KOOS sport/recreation (mean difference, 4.4; 95% CI, 2.1-6.7) and KOOS quality of life (mean difference, 2.4; 95% CI, 0.4-4.4). Female patients reported less improvement from 1 to 2 years postoperatively than male patients in KOOS sport/recreation (mean difference, 3.2; 95% CI, 0.3-6.1). In some age groups, female patients reported a clinically relevant worse KOOS sport/recreation score than male patients (mean difference >/=8). CONCLUSION: Female patients reported statistically significant worse outcomes than male patients before and at 1 and 2 years after ACL reconstruction. In some age groups, this difference was also clinically relevant. There were no clinically relevant sex differences in improvements over time. We suggest that possible sex differences be analyzed in future studies on evaluation after ACL injury/reconstruction.


External organisations
  • University of Southern Denmark
  • Karolinska Institutet
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Sport and Fitness Sciences


  • anterior cruciate ligament, patient outcome assessment, reconstructive, surgical procedures, gender
Original languageEnglish
Pages (from-to)1334-1342
JournalAmerican Journal of Sports Medicine
Issue number7
Publication statusPublished - 2010
Publication categoryResearch

Bibliographic note

The information about affiliations in this record was updated in December 2015. The record was previously connected to the following departments: Division of Physiotherapy (Closed 2012) (013042000), Reconstructive Surgery (013240300), Department of Orthopaedics (Lund) (013028000)