TABLE IV.

Time of Peak Velocity (Percent of Cycle)

	Effect Size*	Normal Subjects	Patients with Cerebral Palsy†
			Preop.	Postop.
Hip
Flexion velocity	2.6	66.8	78.3	78.5
Extension velocity	5.3	24.4	18.9	17.2
Knee
Flexion velocity	5.6	61.5	61.9	62.3
Extension velocity	3.5	87.4	2.2	99.3
Ankle
Dorsiflexion velocity (swing/stance)	3.4/3.3	71.1/11.4	79.4/6.5	78.4/9.9
Plantar flexion velocity	1.7	57.0	59.7	60.5

^*Effect size = the difference required for significance at α < 0.05 with a statistical power of 0.9.

^†Boldface type indicates that the data were significantly different from the value for normally developing subjects (p < 0.05). The results suggest that muscle-tendon lengthening has no effect on knee or hip velocity timing.