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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, METHODS, METHODS, RESULTS. Meshes: Aged, Case-Control Studies, Electromyography, Female, Humans, Isometric Contraction, Knee, Male, Middle Aged, Muscle Weakness, Muscle, Skeletal, Recovery of Function, Stroke, Stroke Rehabilitation, Thigh.
user
Is muscle function of knee extensors and flexors after stroke selectively impaired at shorter muscle lengths? Context: To investigate whether muscle strength is selectively more affected at shorter lengths of thigh muscles as result of stroke and to determine whether this is associated with impaired neural activation at shorter muscle lengths. Case-control study. Fourteen patients with sub-acute stroke, and 12 able-bodied controls. In patients (bilaterally) and able-bodied controls torque and activation was measured during maximal voluntary isometric contractions of knee extensors and flexors at 30 degrees , 60 degrees and 90 degrees knee flexion. The paretic knee extensors showed lower normalized maximal torques (73%) and lower normalized activation (71%) compared with control at 30 degrees . The paretic knee flexors showed lower normalized maximal torques at 60 degrees (64%) and 90 degrees (45%) with non-significantly lower normalized activation (~79% and ~67%, respectively).
assistant
As a result of stroke, lower muscle torque at shorter muscle lengths of the knee extensors is associated with a length-dependent lower voluntary activation, which may also be the case for the flexor muscles, but not with altered co-activation. We recommend investigating the role of specific training of paretic knee extensors and flexors in especially shortened positions to improve recovery of function after stroke. Final Decision: yes