A Prehab Strengthening Program Prior to ACL Surgery on Lower Limb Structure and Function (ACL-Strong)

The Effects of a Lower Limb Strengthening Training Program During Prehabilitation Prior to ACL Surgery on Lower Limb Structure and Function : a Randomized Clinical Trial

Atrophy and weakness are ubiquitous after a ACL rupture and associated with a worsened long-term recovery of individual capacities, despite surgery and rehabilitation. Preoperative rehabilitation (prehab) is believed to prepare patients for surgery and post-operative rehabilitation. However, prehab programs are highly variable, and do not always aim to develop/maintain neuromuscular parameters. The purpose of this study is to assess the effects of a lower limb strengthening training program during prehab prior to ACL Surgery on lower limb structure and function.

Recruited participants will be randomly allocated to one of the three groups of participants constituted in this study. The two first groups will receive prehabilitation prior to ACL reconstruction (differing in program type). All participants will receive standardized post-surgery rehabilitation (based on international recommandations).

Participants received a 9-weeks strengthening-based prehabilitation program before ACL reconstruction, followed by a standardized post-operative rehabilitation program

Participants received a 9-weeks conventional prehabilitation program (targeting pain knee mobility) before ACL reconstruction, followed by a standardized post-operative rehabilitation program

No prehabilitation program Participants received only a standardized post-operative rehabilitation program

Participants received a 9-weeks conventional prehabilitation program (targeting pain knee mobility) before ACL reconstruction, followed by a standardized post-operative rehabilitation program

Maximal muscle strength of knee flexors/extensors will be assessed using isokinetic dynamometer, and extension and flexion torques during a maximum voluntary contraction (MVC). Unit : Newton meter (Nm)

week 0 (baseline); week 9 (post-intervention, short term) ; 6 months after the surgery (post-intervention, mid-term) and 12 months after the surgery (post-intervention, long-term)

Muscle volume of the knee muscles (hamstring and quadriceps) will be assessed using 3D ultrasound imaging, at rest in a prone (hamstring) or supined (quadriceps) position. Unit : millimeters (mL)

week 0 (baseline); week 9 (post-intervention, short term) ; 6 months after the surgery (post-intervention, mid-term) and 12 months after the surgery (post-intervention, long-term)

An index of muscle stiffness will be assessed via the shear modulus using ultrasound shear wave elastography, at rest in a prone (hamstring) or supined (quadriceps) position. Unit : kiloPascals (kPa)

week 0 (baseline); week 9 (post-intervention, short term) ; 6 months after the surgery (post-intervention, mid-term) and 12 months after the surgery (post-intervention, long-term)

Single leg hop test. Participants will be instructed to jump as far as possible on a single leg, without losing balance and landing firmly. The distance is measured from the start line to the heel of the landing leg. Unit : centimeters (cm)

week 0 (baseline); week 9 (post-intervention, short term) ; 6 months after the surgery (post-intervention, mid-term) and 12 months after the surgery (post-intervention, long-term)

Patient's self-related opinion about symptoms and activity will be assessed using the International Knee Documentation Committee Subjective Knee Form (IKDC).The IKDC is consisted of 10 questions. Unit : score, scaled between 0 (=bad) and 100 (= good function)

week 0 (baseline); week 9 (post-intervention, short term) ; 6 months after the surgery (post-intervention, mid-term) and 12 months after the surgery (post-intervention, long-term)

Patient's self-related opinion out the impact of returning to sport will be assessed using the Anterior Cruciate Ligament - Return to Sport after Injury (ACL-RSI) questionnaire. The ACL-RSI consists of 12 questions. Unit : score, scaled between 0 (=bad) and 100 (= more psychologically ready to return to sport)

week 0 (baseline); week 9 (post-intervention, short term) ; 6 months after the surgery (post-intervention, mid-term) and 12 months after the surgery (post-intervention, long-term)

Drugs intakes, dates of physiotherapy/medical consultations, date of return to work will be assessed through a diary Unit : self-reported date, in a paper diary

week 0 (baseline); week 9 (post-intervention, short term) ; 6 months after the surgery (post-intervention, mid-term) and 12 months after the surgery (post-intervention, long-term)

Inclusion Criteria: age : 18 to 55 first episode of ACL injury having a planed ACL reconstruction volunteer to participate Exclusion Criteria: age : <18 or >55 previous episode of ACL injury/reconstruction no ACL reconstruction