TABLE III.

Time of Peak Angle (Percent of Cycle)

	Effect Size*	Normal Subjects	Patients with Cerebral Palsy†
			Preop.	Postop.
Hip
Flexion angle	1.9	93.4	95.5	95.3
Extension angle	2.2	51.6	53.2	54.2
Knee
Flexion angle	2.6	71.6	85.6	82.1‡
Extension angle	3.8	41.2/97.9	33.7	30.0‡
Ankle
Dorsiflexion angle	5.1	39.1	27.0	36.3‡
Plantar flexion angle	1.6	63.6	66.2	66.5

^*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).

^‡These postoperative data were significantly different from the preoperative values (p < 0.05). The results suggest that muscle-tendon lengthening can modify the timing of peak angles.