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. Author manuscript; available in PMC: 2007 Mar 2.
Published in final edited form as: J Bone Joint Surg Am. 2000 Feb;82(2):174–186. doi: 10.2106/00004623-200002000-00003

TABLE VI.

Electromyographic Coactivity for Normal Subjects and Before and After Muscle-Tendon Lengthening in Patients with Cerebral Palsy

Coactivity (percent of maximum)
Effect Size* Normal Subjects Patients with Cerebral Palsy†
Preop. Postop.
Knee
  Range 0.05 0.77 0.61 0.64
  Mean 0.05 0.31 0.53 0.48
  Maximum 0.04 0.85 0.89 0.86
  Minimum 0.04 0.08 0.28  0.21†
  At foot contact 0.09 0.54 0.69 0.63
  At mid-stance 0.07 0.21 0.51 0.51
  At toe-off 0.08 0.31 0.49  0.36†
Ankle
  Range 0.06 0.42 0.60 0.62
  Mean 0.05 0.26 0.45 0.48
  Maximum 0.06 0.51 0.84 0.87
  Minimum 0.04 0.09 0.25 0.25
  At foot contact 0.06 0.35 0.55 0.57
  At mid-stance 0.06 0.24 0.46 0.53
  At toe-off 0.07 0.25 0.41 0.39
*

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). Only knee coactivity at toe-off was modified by muscle-tendon lengthening.