Anterior cruciate ligament (ACL) is a frequent and disabling injury in athletes. Most of the time, ACL reconstruction (ACLR) is consider for regaining function and returning to preinjury sports while reducing the risk of secondary injuries. However, the risk of secondary severe knee injury is increased after ACLR, especially in athletes returning to strenuous activities. If strength symmetry is considered as an important factor in the Return-to-sport (RTS) decision, there is conflicting data about the association between strength symmetry and the risk of second knee injury after ACLR. The main objective of this study was to test if knee muscles strength symmetry at 4 months was associated with the psychological readiness and incidence of subsequent severe injury of both knees at a minimum 2 years follow-up after ACL-R.

Inclusion Criteria:

Patients who have had an ACL reconstruction surgery (isolated or associated with other meniscal or ligamentary surgery) Patient included in the sport medicine follow-up protocole with intermediate and final isokinetic muscular assessment at 3-4 months Patient who received the information form Patients with access to the Internet

Exclusion Criteria:

Patient who did not participate in all follow-up consultations and isokinetic muscular assessments Patients who had a previous knee surgery before the ACLR Cognitive or sensory impairment making it impossible to understand the information form Neurological, traumatic or osteoarticular history responsible for muscle imbalance prior to surgery

All sports patients included in the sport medicine follow-up protocole with isokinetic muscular assessment at 3-4 months after ACL reconstruction surgery since January 2017 with a minium 2 years follow-up in the sports medicine department, Return To Sport Process