Does Gender have a Role in the Effect of Anterior Knee Pain on Functional Disability in IDF Combat Soldiers?
2The Saul and Joyce Brandman Hub for Cardiovascular Research and the Department of Medical Neurobiology, Institute for Medical Research (IMRIC), Faculty of Medicine, The Hebrew University of Jerusalem, Israel
3Department of Orthopedics, MeDES Medical Center, Israel
4Department of Orthopedics, Shaare Zedek Medical Center, Israel
5Department of Orthopedics, Hadassah Medical Organization, Mount Scopus, Israel
6Department of Orthopedics, Israel Defense Forces Medical Corps, Israel
Background/Rationale:
Anterior knee pain (AKP) affects up to 15% of recruits to elite military units. Its incidence is significantly higher in female combatants. Gender differences in the effect of AKP on functional disability have not been reported.
Methods:
This is a subgroup analysis by gender of data from an interventional study (NCT02845869). Inclusion: active combat soldiers/policemen with AKP due to overuse/load. Exclusions: previous trauma, knee surgery, or injury to meniscus/ligament. Outcomes: anatomical pain location, subjective pain level by visual analogue scale (VAS [0=no pain, 100=unbearable pain), and Kujala AKP functional disability questionnaire (0=worst, 100=best). Kujala questions were dichotomized by significance to combat soldiers, and the proportion of the population affected was determined for each. Comparisons of males/females were performed with 2-sample t-test or χ2.
Results:
AKP on the background of overuse/load was diagnosed in 45 men and 27 women (71 and 41 knees, respectively). Female combatants were younger (20.1±1.3-vs-22.9±6.3 years, p<0.001), had lower BMI (23.0±3.2-vs-24.6±3.2 kg/m, p=0.006), and reported doing less pre-induction physical training (67%-vs-89%, p=0.021). Location of pain was similar between male and female soldiers (female-vs-male: patella, 32%-vs-48%, p=0.095; patellar tendon, 59%-vs-51%, p=0.423). Female combatants reported significantly higher subjective pain levels (VAS: 53.5±22.6-vs-44.5±22.9, p=0.046) and decreased overall functionality (Kujala: 67±12-vs-73±11, p=0.030). When analyzed by specific activity, female soldiers had higher frequency of further detrimental effect of AKP when climbing stairs and while running (female-vs-male: stairs, 82%-vs-56%; running, 30%-vs-9%, p=0.025 and p=0.022, respectively).
Conclusions:
Compared to their male counterparts, female combatants with AKP report higher pain levels and greater overall functional disability with significantly more difficulties when climbing/descending stairs or running. This study emphasizes the need for a gender-specific approach to diagnosis and treatment of AKP to achieve optimal outcome and earlier return to service.