Cerebral palsy is the most common disabling condition in childhood, involving a diverse group of movement and posture disorders
of varying etiologies. Yet, much is unknown about how cerebral palsy affects individual joints because currently applied techniques
cannot quantify the three-dimensional kinematic parameters at the joint level. We quantified the effects of cerebral palsy
at the knee using fast phase contrast MRI, with the ultimate intent of improving the assessment of joint impairments associated
with cerebral palsy, improving clinical outcomes, and reducing the impact of cerebral palsy on function. We addressed three
questions: (1) Can patients with cerebral palsy perform the required repetitive extension task? (2) Which of the 12 degrees
of freedom defining complete knee kinematics are abnormal in individual patients with cerebral palsy and is the patellar tendon
moment arm abnormal in these patients? (3) Are the individual kinematic differences consistent with clinical observations?
All patients were able to perform the required task. We found kinematic differences for each patient with cerebral palsy consistent
with clinical findings, in comparison to an able-bodied population. Fast phase contrast MRI may allow differentiation of patellofemoral
and tibiofemoral function in various functional subtypes of cerebral palsy, providing insights into its management.
Each author certifies that he or she has no commercial associations (eg, consultancies, stock ownership, equity interest,
patent/licensing arrangements, etc) that might pose a conflict of interest in connection with the submitted article.
Each author certifies that his or her institution has approved the human protocol for this investigation, that all investigations
were conducted in conformity with ethical principles of research, and that informed consent and assent, if the subject was
a minor, was obtained.
Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author and do not necessarily
reflect the views of the National Institutes of Health or the US Public Health Service.