1. Prof.dr. Taina Avramescu
Erasmus+ Programme
Project RO01-KA
Collaborative learning for enhancing practical skills for patient-focused interventions in gait rehabilitation after orthopedic surgery
COR-skills
GAIT ASSESMENT - RSSCAN gait analysis
Prof.dr. Taina Avramescu
Noiembrie 2012
Project financed by European Commission under the Erasmus + programme, KA2
 This document reflects only the author's view and that the NA and the Commission are not responsible for any use that may be made of the information it contains. E1
, Bucharest

2. Plantar pressure distribution - data interpretation
A wide range of pressure-variables exists throughout literature. Depending on the purpose of the research, pressure-i variables are related to the whole sole of the foot or to specific sub-areas.

3. HL: Heel lateral
HM: Heel medial
MF: Midfoot
M5: Metatarsal 1
M4: Metatarsal 2
M3: Metatarsal 3
M2: Metatarsal 4
M1: Metatarsal 5
T2-T5: Toe 2-5
T1: Hallux

4. Static measurements
- he magnitude of the pressure distribution is shown by a color scale
- in the corner of each quadrant is displayed the relevant percentage of body weight distribution on the correspondent surface.
- By analyzing the recorded image and values ​​can be issued conclusions on the left-right body weight dividing and front-backwards differences.

5. Do you observe any anomaly in left-right dividing of the percentage of the body weight ?
b. yes, the distribution is higher for the left side;
c. yes, the distribution is higher for the right side.
Answer: a.
Explanation. The trainee should determine from static screenshots the stability of the patient. In each corner is displayed a fraction of patient’s weight that’s exerted on the corresponding sole zone. This means adding left and right weight percentages for left/right foot, to determine the weight bearing on that foot. In addition, the trainee should sum the top and bottom quadrants in order to determine weight bearing on forefoot or heel. For figure 1, we can determine:
the distribution for the left sole is 24.17%+24.52% = 48.69%.
- the distribution for the right sole is 24.36%+26.95% = 51.31%
Normal left-right dividing 50%-50%, +/-3%.

6. front-backwards difference diagonal differences
What significant differences in dividing of the percentage of the body weight do you observe in Fig. 2?
front-backwards difference
diagonal differences
no significant differences are seen
left-right difference
Answer: b,d.
Explanation. If from certain reasons the weight is inequally distributed over the four zones (left-right or front-back), this anomaly can be observed just by looking where the intersection is located. For example, a non-egual front-back weight distribution can mean problems related to static pose.
For figure 2, we can determine:
the distribution for the left sole is 18.07%+9.01% = 27.08%.
the distribution for the right sole is 33%+39.92% = 72.92%.
the distribution for the front side is: 9.01% % = 48.93%
the distribution for the back side is 18.07% + 33% = 51.07%.
the distribution for diagonal differences is 18.07% % = 57.99% and 42.01%, respectively.
The image suggests the possibility of:
a. static problems
b. pelvic rotation
c. length difference of lower limbsAnswer: a,b,c.
Explanation. Possible causes for differences:
Proprioceptical problems
Structural problems like a length difference, alignment problems with orthotics-prostethics
Also we must look for large front-backwards difference for each sole that can mean possible static problems, or look for diagonal differences (possible pelvic rotation). It is important to see the patient as a whole, therefore it is possible that a difference is caused by problems at all possible levels: shoulders, hips, knee, ankles, feet. So, there can be many reasons for the differences in the weight partitioning and Footscan can be only be used to recognise these differences. A further verification of possible causes should always be done.

7. Dynamic measurments –contact time

8. Dynamic measurments – force/pressure

9. Dynamic measurments – contact percentage and impulse
In the following picture please indicate the region that has an abnormal contact percentage:
Fig. 13. Dynamic measurement, Impulse screen.
Rearfoot
Forefoot
Midfoot

10. Answer : c
Explanation. This reffers to the relationship between the contact percentage and the bearing of the correspondant region. For example the contact percentage of the midfoot is increased for a flat foot. If there is a lot of contact, is it being loaded as well? This can be controlled by looking at the impulse value of the midfoot.
If the value is very low, the midfoot indeed makes contact, but does not contribute to the bearing of the bodyweight or with rolling off.

11. High arch foot
Normal foot
Flat foot

12. Dynamic measurments – foot axis angle
Foot axis - one end between medial and lateral heel and the other end among metatarsals 2 and 3.
Talar axis (red). As long as the heel applies a normal functional force on the plate, subtalar joint alignment is given by the red line. When the medial and lateral side are in balance, the axis will be aligned with the footaxis. Pronation causes the axis to transfer to the medial side, whilst supination causes it the transfer laterally. Grey axis represent the maximum positions of the subtalar axis (max. adduction and max. abduction).

13. Foot angle (abduction angle) indicates the deviation from the walking direction (plate direction) an is quantified by values that indicates exo or endo rotation: a positive angle indicates exo rotation of the foot, whenever the angle is negative, it indicates endo rotation.
Subtalar joint angle: indicates the amount of pronation in the rear foot during impact. During a step it records minimum and maximum values. The higher the value is - the more pronation occures. Minimum and maximum values give also an indication on the position of the rearfoot in relationship to the ground.
Subtalar joint flexibility reffers to the variation of subtalar joint angle and express talus mobility.

14. Please indicate the subtalar joint flexibility for the right sole in figure 10.
a) the red angle
b) the blue angle
c) this angle is not marked on the figure
Answer: a
Explanation: The flexibility of the subtalar joint is the total variation of the joint angles, in absolute value. For example, if the minimal subtalar joint angle value is -2 degrees and the maximal value is 4 degrees, the subtalar joint flexibility will be = 6 degrees. This variation can tell us what is the torsional strain that the subtalar joint is exposed to; thus it is an indicator of injury risks. A high variation can imply a higher risk of injury or strain over the subtalar joint.
The value of the foot axis angle in figure 10 indicates:
a) exorotation for the right sole
b) endorotation for the left sole
Answer: a, b.
Explanation. Foot angle (abduction angle) indicates the deviation from the walking direction (plate direction) an is quantified by values that indicates exo or endo rotation: a positive angle indicates exo rotation of the foot, whenever the angle is negative, it indicates endo rotation.

18. THANK YOU FOR YOUR ATTENTION!

19. THANK YOU FOR YOUR ATTENTION!