*3.1.7 Cognitive function risk factor*

Neurocognitive performance is one risk factor that has been understudied, though it is potentially a modifiable risk factor. Researchers have been looking into the association of loss of neuromuscular control and noncontact ACL injuries. They hypothesised that reduced baseline neurocognitive functions predispose an individual to ACL injuries. Athletes who had suffered ACL injuries were demonstrated significantly slower reaction time and processing speed. Furthermore, they performed poorly on visual and verbal memory composite scores as compared to the controls. Poor neurocognitive performance is associated with reduced neuromuscular control and coordination issues thereby causing ACL injuries [71].

## *3.1.8 Previous injury*

Previous ACL injury and reconstruction is in itself a risk factor for injury of the contralateral ACL and reinjury of the reconstructed ACL as well [72]. It was found that football players with an old ACL injury and/or reconstruction were predisposed to an ACL injury in either the contralateral knee ACL or the reconstructed ACL graft [73]. Patients who have had ACL reconstruction in the past 12 months have 11 times the risk of sustaining a new / re-injury of the ACL. Some researchers have looked into the incidence of ACL injury in patients who have had other musculoskeletal injuries. It was seen that previous ankle injuries had a correlation to the likelihood of sustaining an ACL injury [74]. However, the site of previous injury and the recovery from the same dictates the risk of having an ACL injury. For example, patients with injuries of the lower limb and trunk have a greater predilection of sustaining an ACL injury as compared to those of the upper limb. Rehabilitation from the injury to pre-injury levels also reduces the risk of sustaining an ACL injury in the future.
