Hamstring Stiffness After Anterior Cruciate Ligament Reconstruction

University Hospital, Caen135 enrolled

Overview

The role of hamstring has been studied in anterior cruciate ligament (ACL) injury prevention, mainly to counteract the anterior tibial translation , especially when contracting eccentrically, but also with passive stiffness. However, little is known about the passive hamstring stiffness after ACL reconstruction (ACLR). The primary objective of this study is to evaluate the passive stiffness of hamstring muscles after ACLR by using an isokinetic device. Secondary, we aimed to test the individual and surgical characteristics associated with hamstring stiffness and the impact of hamstring stiffness on RTS and knee re-injury. The hypotheses are that hamstring stiffness will be lower in the ACLR leg compared to the uninjured leg and to healthy individuals. Also, we hypothesized that hamstring stiffness will be lower after hamstring autograft compared to patellar tendon autograft and will increase progressively after ACLR to be symmetrical at the time for RTS. Also, we hypothesized that hamstring stiffness could be associated with better outcomes at RTS (RTS at same level and lower re-injury rates)

Study Type

OBSERVATIONAL

Enrollment

135

Conditions

ACL Injury Stiffness of Knee, Not Elsewhere Classified Sport Injury

Eligibility

Sex: ALLMin age: 16 YearsMax age: 50 YearsHealthy volunteers:

Medical Language ↔ Plain English

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 4 months and 8 mnths after surgery respectively * Patient who received the information form Exclusion Criteria: * Patient who did not participate in all follow-up consultations and isokinetic muscular assessments * Cognitive or sensory impairment making it impossible to understand the information form * Neurological, traumatic or osteoarticular history responsible for muscle imbalance prior to surgery * Previous severe injury on the ipsilateral or contralateral knee * Recent muscle damage * ACL reinjury ( graft failure) * Patient with genu flexum, or constant flexed knee at 3 months after surgery * Informed consent not obtained

Outcomes

Primary Outcomes

Change in passive hamstring stiffness

Measurement of knee flexors stiffness (in newton.meter per degree, Nm/°) on isokinetic dynamometer.

Time frame: ACLR group: Two evaluations on both injured and healthy knees: (1) 4 months after surgery and (2) 8 months after surgery; Control group:one evaluation at a single point in time through study completion (an average of one year)

Change in Strength

Measurement of knee extensors and flexors peak strength (in newton.meter, Nm) on isokinetic dynamometer.

Secondary Outcomes

Individual characteristics

Personal characteristics recorded in the medical report as age, gender, type of sport and sport level of practice and return to sport after the surgery and severe reinjury on the operated knee or contralateral knee.

Time frame: ACLR group: Two follow-up medical consultations: (1) 4 months after surgery and (2) 2 years after the surgery for return to sport and reinjury; Control group:one evaluation at a single point in time through study completion (an average of one year)

Surgery characteristics

Surgery characteristics recorded in the medical report as the type of surgery, the surgery duration and tourniquet time

Time frame: ACLR group only: one follow-up medical consultations at 4 months after surgery