This study investigated how anterior cruciate ligament (ACL) injuries affect not only the knee joint but also brain activity, reaction speed, and psychological readiness to return to sports. A total of 60 male athletes, aged 18 to 30 years, were evaluated in three groups: healthy athletes, athletes who had undergone primary ACL reconstruction, and athletes who had undergone revision ACL reconstruction.

The study measured brain activity with electroencephalography (EEG), reaction time with a computer-based test, and psychological status with standardized questionnaires. The findings showed that athletes with revision ACL surgery had more difficulties in attention control, slower reaction times, and greater psychological barriers compared to the other groups.

These results suggest that ACL injuries and surgeries may influence not only physical recovery but also brain function and psychological readiness. The study highlights the importance of considering neuromuscular, cognitive, and emotional aspects when planning rehabilitation and return-to-sport decisions.

Inclusion Criteria:

Male athletes

Age between 18 and 30 years

Regular participation in amateur or professional sports

Completion of ACL rehabilitation (for surgical groups) at least 6 months before enrollment

Ability to undergo EEG and reaction time testing

Provision of signed informed consent

Exclusion Criteria:

History of neurological or psychiatric conditions (e.g., epilepsy, ADHD, depression)

Additional lower extremity injuries or orthopedic surgeries

Metal implants or scalp conditions incompatible with EEG

Uncorrected visual or auditory deficits

Systemic illnesses (e.g., diabetes, multiple sclerosis, neuropathy)

Use of psychoactive medication

Any cognitive or physical limitation interfering with testing procedures

Female participants (to avoid hormonal confounding effects on EEG recordings)

The study population consisted of 60 male athletes aged 18 to 30 years. Participants were divided into three groups: healthy controls with no history of knee injury, athletes with primary ACL reconstruction, and athletes with revision ACL reconstruction. All were actively engaged in regular sports participation and had completed ACL rehabilitation at least 6 months prior to enrollment.

Individual participant data (IPD) will not be shared because the dataset is small, contains sensitive neurophysiological and psychological information, and was collected under conditions that limit external data access. Data may be available in aggregated form upon reasonable request to the corresponding author.