My Orthopedic Surgery

Table I in this paper gives details of these scales. Note the paper concluded that the reliability of both these scales was low

Cerebral palsy is a group of disorders affecting the development of movement and posture that are believed to arise from nonprogressive disturbances in the developing fetal or infant brain. In addition to the motor disorders that characterize cerebral palsy, which limit a patient's activities, individuals with cerebral palsy often display epilepsy, secondary musculoskeletal problems, and disturbances of sensation, perception, cognition, communication, and behavior.
Synonyms and related keywords: encephalopathy, spastic palsy, dyskinetic palsy, ataxic palsy, palsy, quadriplegia, diplegia, monoplegia
Thorogood & Alexander 2007

Reliability of Ashworth and Modified Ashworth Scales in Children with Spastic Cerebral Palsy Akmer Mutlu , Ayse Livanelioglu and Mintaze Kerem Gunel BMC Musculoskeletal Disorders 2008, 9:44 Abstract and link to free full text
A prospective cross-sectional observational study was planned to determine the reliability of the Ashworth Scale (AS) and the Modified Ashworth Scale (MAS) in children with spastic cerebral palsy (CP).
Conclusions The interrater and intrarater reliability of AS and MAS are related to muscle and joint characters. The repetition of measurements by the same physiotherapist, and experience may not affect reliability. These scales are not very reliable and assessments of spasticity using these scales should be therefore interpreted with great caution.

Spasticity (meaning to draw or tug) is involuntary, velocity-dependent, increased muscle tone that results in resistance to movement. The condition may occur secondary to a disorder or trauma, such as a spinal cord injury (SCI), a brain injury, a tumor, a stroke, multiple sclerosis (MS), or a peripheral nerve injury. A lag time may exist between injury and spasticity onset, and severity may wax and wane over time. Spasticity may be static or dynamic in nature. Although many therapeutic and medical interventions can attenuate its effects, spasticity can be severely debilitating.
Synonyms and related keywords: hypertonicity, spasm, multiple sclerosis, MS, cerebral palsy, CP, traumatic brain injury, TBI, spinal cord injury
Elizabeth A Moberg-Wolff, MD