Classification of idiopathic toe walking based on gait analysis: development and application of the ITW severity classification.

Idiopathic toe walking (ITW), considered abnormal after the age of 3 years, is a common complaint seen by medical professionals, especially orthopaedic surgeons and physiotherapists. A classification for idiopathic toe walking would be helpful to better understand the condition, delineate true idiopathic toe walkers from patients with other conditions, and allow for assignment of a severity gradation, thereby directing management of ITW. The purpose of this study was to describe idiopathic toe walking and develop a toe walking classification scheme in a large sample of children. Three primary criteria, presence of a first ankle rocker, presence of an early third ankle rocker, and predominant early ankle moment, were used to classify idiopathic toe walking into three severity groups: Type 1 mild; Type 2 moderate; and Type 3 severe. Supporting data, based on ankle range of motion, sagittal joint powers, knee kinematics, and EMG data were also analyzed. Prospectively collected gait analysis data of 133 children (266 feet) with idiopathic toe walking were analyzed. Subjects' age range was from 4.19 to 15.96 years with a mean age of 8.80 years. Pooling right and left foot data, 40 feet were classified as Type 1, 129 were classified as Type 2, and 90 were classified as Type 3. Seven feet were unclassifiable. Statistical analysis of continuous variables comprising the primary criteria showed that the toe walking severity classification was able to differentiate between three levels of toe walking severity. This classification allowed for the quantitative description of the idiopathic toe walking pattern as well as the delineation of three distinct types of ITW patients (mild, moderate, and severe).