1. Normal Gait vs. Prosthetic Gait
Clinical Course R&D
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2. Normal Gait Cycle – 2 phases
• Stance Phase
Time the foot is in contact with the floor
• Swing Phase
Time the foot is in the air
Stance Phase
60%
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Swing Phase
40%

3. Divisions of the Gait Cycle- 8 phases
Stride
(Gait Cycle)
Periods
Stance
Swing
Tasks
Weight
Acceptance
Single Limb
Support
Limb
Advancement
Phases
Initial
Loading
Mid
Contact Response Stance
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Terminal
Stance
Pre
Swing
Initial
Swing
Mid
Swing
Terminal
Swing

4. Normal Gait Cycle
Perry 1992
Inman 1981
1. Initial Contact
Heel strike
(0 - 2%
of the GC)
2.Loading Response
Foot Flat
(2 -12%
of the GC)
3.Mid-Stance
Mid Stance
(12 - 30% of the GC)
4.Terminal Stance
Heel Off
(30 – 50 % of the GC)
5.Pre-Swing
Heel Off - Toe Off
(50 – 60 % of the GC)
6.Initial Swing
Toe Off - Early Accl.
(60 – 73 % of the GC)
7.Mid-Swing
Mid Swing
(73 – 87 % of the GC)
8.Terminal Swing
Deceleration
(87 -100 % of the GC)
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5. Loading Response
Loading reponse phase
GRF
100% BW
• 60% of the body
weight is transferred in
0,2 sec
time
12%
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6. Loading Response
•In normal gait the body weight
has a free fall in the end of
terminal swing
•The body weight falls about
1 cm causing high impact
•The human body immediately
reacts with controlled plantar
flexion
•The quadriceps controls
knee flexion in early stance
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7. Stance phase vs speed
• Increasing speed results in
increased impact.
Walk
Slow Walk
200
Run
• Shock absorbing systems
assist to achieve natural
gait and reduce impact
100
0
0
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62%

8. Terminal Stance
• Maximum angle in the toe joint
shows 55° in pre swing
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9. Terminal Stance
The forefoot lever arm
stabilizes the knee and
supports the center of
mass
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10. Terminal Stance
•Full length toe lever prevents:
- pelvis from droping
- knee instability
•Resulting in:
- symmetrical gait
- more equal stride length
- reduced impact on
the sound side
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11. Rotation
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12. Speed and Gait
Stance Phase
Swing Phase
60%
40%
5 km/h
7 km/h
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13. Speed and Gait
•
Swingtime related to walking speed
0,55sec
0,40sec
0,8 m/sec
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1,8m/sec

14. TT Typical Prosthetic Gait
1.
2.
3.
4.
5.
6.
Shortened midstance
Reduced stance flexion
Early heel off
Early toe off
Reduced stance phase time
Reduced knee flexion in swing
(Breakey 1976)
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15. Prosthetic issues resulting in pathologic gait - TT
Typically prosthetics are too short!
WHY?
•Lack of suspension
•Potential Clinical issue: shorter prosthetic leg
(Lilja et al. 1994)
•Increased hip to toe distance:
•Lack of dorsiflexion
•single axis knee design
(Gard et al. 1996)
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16. Prosthetic issues resulting in pathologic gait
- TF
• Average ground clearance
1,29cm
Winter DA. Foot trajectory in human gait: a precise and
multifactorial motor control task. Phys Ther 1992; 72:1:55-66
• Average socket pistoning
10mm
Erikson, Roentgenological Study of certain Stump-Socket Relationship in Above-knee Amputees with Regard to
Tissue Proportios, Socket Fit and Attachment Stability. Upsala J Med Sci, 1973. 78: p. 203-214.
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17. Pathologic Gait TF
Circumduction
Vaulting
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Hip Hiking
Duchenne

18. Pathologic Gait TT
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19. Plantar
Dorsiflex. in °
Plantar
Dorsiflex. in °
Ankle motion in stair walking
Ascent
Stance
Swing
Descent
Swing
Stance
Normal
(Andriacchi et al.1991)
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Prosthetic
(Powers et al. 1997)

20. Shortcomings of prosthetic foot design
with respect to kinematics
•Kinematics:
The angular ranges are generally
larger during stair walking
than during level walking.
Ascend:
IC in dorsiflexion TS in plantarflexion
Descend:
IC in plantarflexion TS in neutral
R. Riener et al. / Gait and Posture 15 (2002) 32–44
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21. Shortcomings of prosthetic foot design with
respect to kinematics
•Decline:
IC in slight
plantarflexion
TS in dorsiflexion
M. Kuster,S. Sakurai, G A Wood PhD
Kinematic and Kinetic Comparision of downhill and level ground walking
Clinical Biomechanics Vol. 10,No. 2, pp. 79-84, 1995
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