Biomechanical and neuromuscular assessment of the knee joint during challenging dynamic tasks.

Developing a new method of measuring dynamic knee stabilityThe complex process to maintain dynamic joint stability is achieved through an interaction between static and dynamic restraints. Dynamic joint stability is the result of the integration of a feedforward mechanismand feedback from the sensorimotor system and the efferent response regulated by an individuals neuromuscular control. The ability to maintainstability by means of dynamic restraints is extremely important to protect the joint surface and the passive structures during daily movement and sports performance. While the importance of dynamic stability in the knee to protect the joints is well-accepted by researchers and clinicians, there is still no consensus about the most accurate and reliable way to measure it. At present, objective and standardized criteria and measurement tools to evaluate dynamic knee stability are limited. Sofar the focus in literature has mainly been on static knee laxity to demonstrate stability whereas the dynamic component has not been well investigated. In addition to the static laxity tests, clinicians and researchers do evaluate dynamic knee stability by means of dynamic tests (hoptests, jump tasks, side-cutting maneuvers,). These dynamic tests stillhave major flaws. The parameters measured reflect indirectly knee stability but are also influenced by othernbsp;factors than stability such as muscle strength, jump capacity, decreased neuromuscular control in the uninjured limb (LSI), familiarity with the task, Furthermore, sufficient quadriceps muscle strength is required to be able to perform a hop test or a jump test. So, it is difficult and often impossible to perform these tests in older people or in subjects just after surgery (eg. ACL reconstruction). Functional measurement methods consist mostly of planned and anticipated tasks performed in a stable environment where it has been shown that dynamic knee stability is mostly challenged in an unstable environment during unexpected movements. Finally, most ofthese tests challenge the knee in a single plane whereas it has been shown that stability is mostly challenged in multiple planes. Therefore, it has been suggested that a valid dynamic knee stability test should simulate all loading and moments acting on the knee encountered during dynamic activities in multiple planes.Based on the flaws of the presently available tests assessing stability, the aim of the present research project is to develop a novel measurement method to quantify the dynamic knee stability. To overcome the most important flaws of the available tests, we will develop an unexpected, repeatable perturbation task that challenge knee stability in multiple planes using a moving platform.General aimTo develop and validate a novel measurement method to quantify the dynamic knee joint stability in different populations.Specific aims1.nbsp;nbsp;nbsp;To develop perturbationtasks on a moving platform that challenge dynamic knee stability in a similar way as in sports participation or activities of daily life. 2.nbsp;nbsp;nbsp;To establish the parameters ofthe task performance that best quantify dynamic knee stability. Furthermore, to investigate the reliability, validity and responsiveness of thetest.nbsp;nbsp;nbsp; To design a neuromuscular training program addressing the modifiable dynamic joint stability parameters. To pilot test the effect of this 12 weeks training program on dynamic stability of the knee in a well defined population with diminished dynamic knee joint stability (subjects with an ACL reconstruction) compared with usual rehabilitation.nbsp;

Publication year:2015