GAIT ANALYSIS

1. GAIT ANALYSIS

2. Closed Kinetic Chain: when the limb is weight bearing; movement of a distal joint influences the position of the joints proximal to it. Stance Phase Open Kinetic Chain: when the limb is non-weight bearing; movement of a proximal joint influences the position of the joints distal to it. Swing Phase

3. Gait Phase

4. Walking & Running Phases Stance/Support Phase: Begins with initial heel strike & ends at toe-off Foot strike/Initial contact � begins when the foot touches the ground (opposite limb is in push-off) (22% of cycle) Loading response � lasts until the opposite extremity has left the ground & the double limb support has ended Midstance � when weight is directly over the foot; concludes when center of gravity is directly over foot Terminal stance � begins as center of gravity passes over the foot; ends just before the opposite limb makes initial contact with the ground Push off/Pre-swing � begins with the initial contact of the opposite limb; ends with toe-off of the stance limb (when the body is being propelled forward) All of this is 62% of the gait cycle. It provides support of the body weight during forward movement. CLOSED KINETIC CHAIN.

5. Walking & Running Phases Swing/Recovery Phase: Begins at time in which the leg is moved from behind the body to a position in front of the leg preparing for heel strike Initial swing � begins at point when toes leave the ground & continues until the knee reaches max. flexion (approx. 60�) Midswing � knee extends from point of max. flexion to the point at which the tibia reaches a vertical position perpendicular to the ground Terminal swing � begins at end of midswing & ends at initial contact during the stance phase OPEN KINETIC CHAIN

6. Walking & Running Phases One cycle: from foot strike until that foot strikes the ground again Walking: One foot is always in contact with the ground. Period of time when both feet are simultaneously in contact with the ground. Running: Period of time when neither foot is in contact with the ground. Foot�s function during running support phase: At heel strike � acts as a shock absorber to impact forces Adapts to the uneven ground Push-off: foot functions as a rigid lever to transmit the explosive forces from the lower extremity to the running surface Heel-strike: contact of the foot is on the lateral aspect of the calcaneus

7. Muscle Contraction during Running Phase Anterior compartment of leg - is active 70% - producing concentric & eccentric contractions Gastrocnemius-soleus complex - active during late stages of swing phase & approx. 70% of stance phase Quadriceps group � works in eccentric fashion during early stages of stance phase (controls amount of knee flexion); begins concentric contractions in later stages of swing phase as it actively extends the knee Hamstrings � provides motion at knee & hip At knee � active late in swing phase & early in stance phase; eccentrically controls knee extension At hip � contract in unison with gluteus maximus to create extension during stance phase

8. Muscle Contraction during Running Phase Hip flexors � active in late stance & throughout swing phase Hip abductors � active throughout stance; helps to keep pelvis as level as possible during unilateral weight bearing Hip adductors � active during late stance through early swing phase

9. Foot Movement Foot pronation occurs immediately after heel strike. Pronation unlocks the mid-tarsals joints, Dampens the shock of heel strike, Allows the forefoot to become more flexible to adapt to various surfaces. **Very important in dissipating the constant stress of foot contact & serves to absorb shock.

10. Foot Movement Midstance observation: Foot needs to be flexible on contact & rigid on push off Accomplished by pronation & supination during weight bearing During midstance, the foot begins to supinate Supination locks the midtarsal joints, stabilizes the forefoot, & provides a rigid lever for push off. The foot usually remains in supination during the swing phase until the next heel strike. Problems arise when pronation continues past midstance & into the propulsive phase. Limits the effectiveness of the propulsive action.

11. Foot Movement Excessive & prolonged pronation flattens the medial longitudinal arch & transfers abnormal stresses & torques to the lower extremities. **Can lead to overuse syndromes, fatigue, & a less efficient athletic performance.

12. Observations of Gait Analysis Limb Position Normal Standing Alignment Anteriorly: ASIS ? patella ? web between 1st & 2nd toes Laterally: Greater trochanter of femur ? patella ? lateral malleolus Range of Motion � entire lower extremity Speed of motion Force Production Timing of each event in the gait cycle

13. Observations of Gait Analysis Feet & Ankles Knees Hips Back