PROJECT PARTNERS
· University of Paderborn
FUNDING
· None
BACKGROUND
Rehabilitation progression and return to play decisions after anterior cruciate ligament reconstruction are based on measures within the psychomotor domain.
Strength, flexibility and speed are the ground motor skills, which are commonly assessed by clinicians. New sensor technology allows quantifying movement quality and balance in a more easy way.
Investigators studying neuroplasticity after ACL reconstruction (ACLR) have suggested a possible visual-motor control alteration after injury that remains unresolved after conventional therapy. Recently, patients who were 3 years after ACLR demonstrated altered knee range of motion wearing stroboscopic glasses during a drop landing task. It is unknown whether these alterations are also present in the first year after ACLR. Whether or not motor output is affected by the amount of visual input is also questioned.
In the light of the return to sports (RTS) continuum decision making process, it would be of interest if the outcomes of commonly used hop tests will reveal differences in conditions with and without wearing stroboscopic glasses. It is known that patients after ACLR have altered kinematics, however based on recent findings it is hypothesized that a more pronounced effect will occur if patients perform a balance task and hop test with stroboscopic vision (SV).
OBJECTIVES
The purpose of this observatory study is to determine the effect of SV on a set of performance test outcomes in patients with a history of ACLR. The patients will be performing a hop test in normal visual conditions as well as during SV in a counterbalanced order.
Patients will be recruited from an outpatient sports physical therapy clinic in Utrecht, the Netherlands. Patients are routinely tested at 6, 9 and 12 months after ACLR and will perform several tests in 2 conditions 1) normal full visual condition 2) stroboscopic vision (SV). In order to assure that patients have no visual impairments prior to measurements, a validated visual test using the Bioptor will be carried out. Measurements include:
Single leg hop test for distance. First maximal hop distance for the injured leg will be determined. In order to standardize conditions for this study, 50% of the maximal hop distance will be used for both legs. 3 hop tests will be performed per side.
Maximal single leg hop for distance (best of 3). Absolute (per side) and relative limb symmetry index (LSI) outcomes will be studied.
Maximal triple hop for distance (best of 3). Absolute and relative LSI will be studied.
Side hop. Patients will perform a maximum number of hops over 2 lines, 40 cm apart.
Balance task. This will be assessed in two conditions during a 30 sec static balance task on a pressure plate (RSScan).
Outcome measures on the hop tests:
Distance jumped
Absolute and relative LSI
Number of hops for side hop
Hip and knee kinematics using IMU’s
Outcome measure on the balance task:
Center of Pressure
Balance error scoring system (BESS)