Gait cycle

gait cycle and pathological gaits

1. GAIT CYCLE Dr. HARSHA NANDINI.T M.S ORTHO

2. GAIT Interplay between loss and recovery of balance with constant change of the gravity causing the forward propulsion of an organism from one place to another is defined as gait.

3. Gait cycle The cycle begins when the foot strikes the ground and ends when the same foot strikes the ground again. The cycle is divided into : STANCE PHASE (60%) SWING PHASE(40%) Stance phase begins when the foot strikes the ground and ends when the foot leaves the ground,at which point the swing phase commenses .

4. STANCE PHASE refers to the period while the foot is in contact with the ground. During walking at any point one foot is in contact with the ground: SINGLE STANCE When both feet are in contact with the ground : DOUBLE STANCE SWING PHASE refers to the period when the foot is in air, enabling limb advancement.

5. STANCE PHASE INITIAL CONTACT LOADING RESPONSE MID STANCE TERMINAL STANCE PRE-SWING

6. INITIAL CONTACT Heel is the first part of the foot to touch the ground. The hip is flexed Knee is extended Ankle is dorsiflexed to neutral.

7. LOADING RESPONSE Beginning of double stance period. Foot contacts the floor,continues until the opposite foot is lifted for swing. Body weight is transferred onto a supporting leg. Opposite leg is in preswing phase.

8. MID STANCE PHASE Begins with the lifting of the opposite foot continues till body weight is aligned over the supporting foot. The supporting leg advances over the supporting foot by Ankle dorsiflexion Hip and knee extended Opposite leg is advancing in its midswing phase.

9. TERMINAL STANCE Begins when the supporting heel rises and continues until the heel of the opposite foot hits the ground. Hip and knee extended Ankle in neutral

10. PRE-SWING PHASE It begins with the initial contact of the previous swing limb and ends with toe-off of the previously supporting leg. increase ankle plantarflexion. Increase knee flexion Decrease hip extension. Transfer of the body weight from ipsilateral to opposite limb takes place.

11. SWING PHASE INITIAL SWING: Begins when the foot is lifted from the ground. The swing leg is advanced by Increased hip flexion Increased knee flexion The ankle only partially dorsiflexes to ensure the toe clearance. The supporting leg is in midstance.

12. MID SWING PHASE End point of the initial swing continues until the swinging limb is in front of the body and the tibia is vertical. Advancement of the swing leg is accomplished by further hip flexion. The knee is allowed to extend in response to the gravity while the ankle continues dorsiflexion to neutral. The supporting leg is in late mid stance.

13. TERMINAL SWING Begins when the tibia is vertical and ends when the foot touches the floor. Limb advancement is completed by knee extension. The hip maintains its flexion and ankle remains dorsiflexed to neutral.

14. MUSCLE CONTRACTIONS Eccentric contraction: Lengthening with contraction Commonest type. Enables an antagonist muscle to dampen the action of an agonist and to act as shock absorber. Stabilizes the joint motion during the gait Quadriceps during initial contact Tibialis anterior muscle contracts eccentrically at initial contact to slow down plantar flexion at ankle.

15. 2. Concentric contraction : Muscle shortening with contraction. Generates power and enables to advance joint through space. Gastrosoleus and iliopsoas are the primary accelerators of gait. Concentric contraction of these muscles occur in terminal stance phase thus gaining momentum for the swing phase.

16. GAIT PARAMETERS

17. STEP LENGTH The linear distance between from the heel strike of one limb to the next heel strike of opposite limb. Normal: 0.7 – 0.9m

18. STRIDE LENGTH The linear distance from the heel strike of one limb to the next heel strike of the same limb.

19. CADENCE The no. of steps taken by a person per unit time. CADENCE=no. of steps /time NORMAL: 90-120 steps/min

20. FOOT PROGRESSION ANGLE The angle made by the long axis of foot (centre of heel to the 2 nd metatarsal) and the line of progression of foot.

21. PATHOLOGICAL GAIT The pathologies that affect the gait usually compromise the joint mobility and muscle activity by 3 general mechanisms. MUSCULOSKELETAL PROBLEMS NEUROMUSCULAR PROBLEMS PAIN

22. LIMPING: in limping the patient avoids weight bearing on the affected side as far as possible –diminished stance phase. It denotes a painful condition of the affected side. LURCHING: in lurching the patient prolongs the stance phase to improve the stability. It denotes the failure of the abduction mechanism.

23. TRENDELENBURG GAIT The action of the abductors to pull the pelvis downwards in the stance phase becomes ineffective. Patient lurches on the affected side and pelvis drops on the opposite side.

24. Seen in Poliomyelitis Muscular dystrophies CDH

25. GLUTEUS MAXIMUS GAIT Normally when the body moves forward in the midstance phase,the hip is extended by gluteus maximus tilting the pelvis backwards to retain the centre of gravity over the supporting leg. In gluteus maximus weakness the stabilizing factor is lost. The patient leans backwards at the hip to passively extend it and keep centre of gravity over the stance leg resulting in backward lurch.

26. Seen in Poliomyelitis

27. GLUTEUS MEDIUS GAIT Also known as abduction lurch The weakened gluteus medius forces the patient to lurch towards the involved side to place the centre of gravity over the hip.

28. QUADRICEPS GAIT Seen classically in PPRP Quadriceps functions as knee stabilizer during gait and prevents knee from getting buckled. So the patient develops alternate mechanisms to lock the affected knee in hyprextension resulting in different variants of gait like Hand to knee gait Hand to thigh gait

29. ANTALGIC GAIT To minimize the pain on weight bearing limb,the person shortens the time duration of the stance phase and quickly transfers the weight to the painless leg. Thus there is longer stance on the painless leg and shorter stance on the painful leg.

30. HIGH STEPPING GAIT Ankle dorsiflexors act during the swing phase of the gait cycle During walking the foot slap in the ground on heel strike and then drops in the swing phase. To prevent this the patient flexes the hip and knee excessively in order to clear the ground. Seen in FOOT DROP

31. HEMIPLEGIC GAIT Slow Decrease in step length Increase in stance phase Circumduction to allow toe clearance. Seen in CVA

32. FESTINANT GAIT Patient takes short steps so that the feet barely clears the floor. Seen in PARKINSON’S DISEASE.

33. SCISSORING GAIT Bilateral adductor spasm at the hip and equinus spasm at the ankle. Leg goes into marked adduction in the swing phase so that the foot with equinus goes across to the opposite side. Seen in CEREBRAL PALSY

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