Stride Analysis

Each lab group should bring:

Our laboratory session employs footprint and gait grid analyses, and a timed walk. For every technique, let your subjects walk at a comfortable speed. Allow them room to take two full steps before and after those steps for which you collect data.


Footprint analysis

Footprint analysis is a relatively simple technique with many variations (Scrutton, 1969; Shores, 1980; Clarkson, 1983; Embrey, 1985).

Equipment:

newsprint
markers pens (2 colors)
scissors

tape measure or yardstick
stopwatch
moleskin
goniometer
calculator
data collection forms

Procedure:

1. Remove subjects' shoes and let them sit in a chair on the end of a newsprint runway.

2. Using the shapes to the right as approximate guides, cut two squares and two triangles of moleskin. Affix the moleskin by its adhesive side to the sole of either shoe; place the squares on the midline of either heel, and the triangles under either second ray. Impregnate the moleskin with the marker pens, using the two colors to distinguish between the right and left foot.

3. Prepare to collect data as your subject walks. One person uses the stopwatch to time the subject's walking, so you can calculate average cadence (in steps/min.) and velocity (in meters/sec.) The timer starts and stops the watch on any two initial contacts, and recalls which footprints correspond to these initial contacts. Because we are calculating average velocity, a sample of longer duration will be more accurate than a shorter sample. When calculating cadence, determine correctly the number of steps for which you have data. Note, for instance, that the data for 5 initial contacts includes only 4 steps.

4. After your subject has donned shoes and walked down the runway, reduce the data by referring to the terms and definitions in the figure to the right.

  1. Mark reference points (RP) on each heel mark.

  2. Draw two reference lines (dashed lines in the figure) to connect the reference points from ipsilateral heel marks.

  3. Draw a midline (ML) between the reference lines.

  4. Measure walking base (WB), the total distance between the right and left side reference lines) by drawing perpendicular lines from the midline to a right and left reference point. The sum of the lengths of the two lines is the walking base.

  5. Measure right and left step lengths (SL), the distance on the midline between heel marks of opposite feet.

  6. Measure right and left stride lengths (ST), the distance on the midline between heel marks of the same feet.

  7. Measure right and left foot angles (FA). The foot angle, whose vertex is the heel mark or reference point (RP), is formed by the limb's reference line and by a line that connects the limb's heel and toe marks.

  8. Calculate average cadence and velocity (see #3 above).

5. Compare your subject's stride analysis measures with typical ones.


Gait grid analysis

Therapists can construct a gait grid pattern in a clinic hallway.

Equipment:

stopwatch
calculator
data collection forms

Robinson and Smidt (1981) describe a gait grid procedure that requires a stopwatch and portable tape recorder.

  1. The subject looks straight ahead and walks across the gait grid at a comfortable pace and with no effort at aiming the lower extremities.
  2. The therapist follows the subject closely and speaks into the tape recorder the initial contact locations that are marked on the grid.
  3. The therapist or an assistant times the period between the first and last recorded initial contacts using a stopwatch.

The published approach is impractical unless the subjects walks very slowly. However, working as a team, lab groups can collect the location of each initial contact and the duration between the first and last initial contacts.

Calculations:

  1. Calculate right and left step and stride lengths. The laboratory's gait grid is calibrated so that each segment has a length of 3 cm.
  2. Calculate average velocity (in meters/sec) and cadence (in steps/min). Be careful to determine correctly the number of steps for which you have data. Note, for instance, that the data for 5 initial contacts includes only 4 steps. This technique does not permit calculation of the walking base.

Compare your subject's stride analysis measures with typical ones.


Timed walk

Accompany your lab partner as he or she navigates your facility's walking course, which is marked and whose distance is known. Using a stopwatch and your count of your partner's steps, calculate average velocity and cadence. Compare your subject's walking velocity and cadence with typical values.

Clinics' walking courses can vary in distance but should approximate the distances that people must walk to be independent in their communities. Robinett and Vondran (1988) discovered that people must walk more than 300 meters to visit supermarkets in most towns with populations of 10,000 or larger. To qualify as "independent community ambulators," people must be able to walk far enough, and fast enough; a speed of 80 meters/minute is necessary to cross streets safely in most communities (Lerner-Frankiel, Vargas, Brown, Krusell, & Schoneberger, 1986; Robinett & Vondran, 1988).


References: Clarkson, B.H. (1983). Absorbent paper method for recording foot placement during gait. Physical Therapy, 63, 345-346.

Embrey, D.G. (1985). A practical method for evaluating foot placement during gait. Physical and Occupational Therapy in Pediatrics 5, 27-31.

Lerner-Frankiel, M.B., Vargas, S., Brown, M., Krusell, L.., & Schoneberger, W. (1986). Functional community ambulation: What are your criteria? Clinical Management in Physical Therapy, 6(2), 12-15.

Robinett, C.S, & Vondran, M.A. (1988). Functional ambulation velocity and distance requirements in rural and urban communities. A clinical report. Physical Therapy, 68, 1371-1373.

Robinson, J.L., & Smidt, G.L. (1981). Quantitative gait evaluation in the clinic. Physical Therapy, 61, 351-353.

Scrutton, D.R. (1969). Footprint sequence of normal children under five years old. Developmental Medicine and Child Neurology, 11, 44-53.

Shores, M. (1980). Footprint analysis in gait documentation: An instructional sheet format. Physical Therapy, 60, 1163-1167.


Last updated 4-24-02 © Dave Thompson PT