title: Letter: Spasticity, passive stretch, and knee extension.
mesh_terms: D006429:Hemiplegia / Q000503:physiopathology*; D006801:Humans; D007717:Knee; D009119:Muscle Contraction; D009128:Muscle Spasticity / Q000503:physiopathology*; D011187:Posture; D012018:Reflex