KINESIOLOGY OF WALKING Dr. Michael P. Gillespie

WALKING (AMBULATION) Ideally, walking is performed efficiently to minimize fatigue and safely to prevent falls and associated injuries. Healthy people can ambulate wile carrying on a conversation, looking in various directions, and even handling obstacles and other destabilizing forces with minimal effort. Individuals at both ends of the lifespan experience challenges with ambulation. Dr. Michael P. Gillespie

WALKING AT VARIOUS STAGES IN LIFE Dr. Michael P. Gillespie

WALKING AT VARIOUS STAGES IN LIFE Early in life, the young child needs 11 to 15 months to learn how to stand and walk. By 4-5 years of age they refine the pattern of gait so that it looks like that of an adult. Decreased strength, decreased balance, and disease in the elderly become a gait challenge. The elderly may require a cane or walker to ambulate safely. Dr. Michael P. Gillespie

WALKING = INDEPENDENCE “Nothing epitomizes a level of independence and our perception of a good quality of life more than the ability to travel independently under our own power from one place to another. We celebrate the development of this ability in children and try to nurture and sustain it throughout the lifespan.” – A. Palta Dr. Michael P. Gillespie

MAREY’S INSTRUMENTED SHOES FOR THE MEASUREMENT OF GAIT Dr. Michael P. Gillespie

MURRAY USED REFLECTIVE TARGETS AND A CAMERA WITH THE SHUTTER OPEN TO ANALYZE GAIT Dr. Michael P. Gillespie

ANALYSIS OF HUMAN MOTION Dr. Michael P. Gillespie

INSTRUMENTATION IN A TYPICAL GAIT LABORATORY TO STUDY WALKING Dr. Michael P. Gillespie

SPATIAL AND TEMPORAL DESCRIPTORS Gait Cycle Stance and Swing Phases Dr. Michael P. Gillespie

GAIT CYCLE Walking is the result of a cyclic series of movements. It can be characterized by a detailed description of the gait cycle (the fundamental unit of walking). Foot contact typically begins with the heel. The beginning of the gait cycle is typically referred to as heel contact or heel strike. The 100% point or completion of the gait cycle occurs as soon as the same foot once again makes contact with the ground. Initial contact is often used in place of heel contact. Dr. Michael P. Gillespie

GAIT CYCLE A stride (synonymous with a gait cycle) is the sequence of events taking place between successive heel contacts of the same foot. A step is the sequence of events that occurs within successive heel contacts of opposite feet (i.e. between left and right heel contacts). A gait cycle has two steps- a left step and a right step. Dr. Michael P. Gillespie

GAIT CYCLE 15-6 Dr. Michael P. Gillespie

SPATIAL DESCRIPTORS OF GAIT Stride Length – the distance between two successive heel contacts of the same foot. Step Length – the distance between successive heel contacts of the two different feet. Comparing right and left step length can be useful in evaluating symmetry of gait in the lower extremities. Step Width – step width is the lateral distance between the heel centers of two consecutive foot centers (average 8 to 10 cm). Foot Angle – the amount of “toe-out”. The angle between the line of progression of the body and the long axis of the foot (average 5 to 7 degrees). Dr. Michael P. Gillespie

SPATIAL DESCRIPTORS OF GAIT 15-7 Dr. Michael P. Gillespie

COMPONENTS OF GAIT CYCLE Heel contact (heel strike) Stride Step Stride length Step length Step width Foot angle Dr. Michael P. Gillespie

TEMPORAL DESCRIPTORS OF GAIT Cadence – the number of steps per minute (also called step rate). Stride Time – the time for a full gait cycle. Step Time – the time for completion of a right or left step. With symmetric gait, step time can be derived from cadence. Dr. Michael P. Gillespie

SPATIAL-TEMPORAL DESCRIPTOR Walking Speed Dr. Michael P. Gillespie

WALKING SPEED Walking Speed combines both spatial and temporal measurements by providing information on the distance covered in a given amount of time. The units of measure are typically meters per second (m/sec) or miles per hour (mph). Calculating speed Measure the time it takes to cover a given distance. Measure the distance covered in a given amount of time. Multiply the step rate by the step length. Speed may be the best and most functional measurement of an individual’s walking ability. Dr. Michael P. Gillespie

WALKING SPEED For healthy adults, a gait cycle (2 consecutive steps) takes slightly more than 1 second and covers approximately 1.44 m (4.5 feet). This results in a walking speed of 1.37 m/sec. At a freely chosen walking speed, women exhibit a slower walking speed, shorter step length, and faster cadence than men. These differences are likely in part due to anthropometric disparities between genders; however, even when anthropometrically matched with men, women still demonstrate a higher cadence and shorter step length than men when walking at the same speed. Dr. Michael P. Gillespie

NORMAL VALUES FOR WALKING Walking speed: 1.37 m/sec (3 mph) Step rate: 1.87 steps/sec (110 steps/min) Step length: 72 cm (28 inches) Dr. Michael P. Gillespie

METHODS TO INCREASE WALKING SPEED Longer step length. Shorter gait cycle (faster walking cadence). Dr. Michael P. Gillespie

METHODS TO INCREASE WALKING SPEED Dr. Michael P. Gillespie

INFLUENCE OF IMPAIRMENT ON STEP LENGTH 15-8 Dr. Michael P. Gillespie

INFLUENCE OF IMPAIRMENT ON STEP LENGTH 15-8 Dr. Michael P. Gillespie

ABNORMAL GATE EXAM PARKINSON’S DISEASE Parkinsonian Gait Demonstration
This type of gait is seen with rigidity and hypokinesia from basal ganglia disease. The patient's posture is stooped forward. Gait initiation is slow and steps are small and shuffling; turning is en bloc like a statue. https://www.youtube.com/watch?v=7SyTpEdhBL w https://www.youtube.com/watch?v=ylHZWO17W 70 Dr. Michael P. Gillespie

STANCE AND SWING PHASES To describe the events taking place during the gait cycle, it is customary to subdivide the gait cycle from 0% to 100%. Heel or foot contact with the ground is considered the start of the gait cycle (0%). The next ground contact made from the same foot is considered the end of the gait cycle (100%). A full gait cycle can be divided into two major phases. Stance phase (from right heel contact to right toe off). The right foot is one the ground supporting the body’s weight. Swing phase (from right toe off to the next right heel contact). The right foot is in the air, being advanced forward for the next contact with the ground. Dr. Michael P. Gillespie

SIMPLE CLINICAL MEASUREMENTS OF WALKING Sophisticated instrumentation such as walkways and foot switches exist to make spatial and temporal measurements; however, these are not necessary. Average walking speed can be measured using a stopwatch and a known distance. Step length and step width can be measured using ink marks made by shoes or feet on a roll of paper covering the floor. Documents abnormal gait patterns including asymmetry in step length. Dr. Michael P. Gillespie

MINIMUM STANDARDS BASED ON COMMUNITY-LIVING ACTIVITIES Compare your results with normal values or with minimum standards required to perform a specific task (i.e. crossing the street within the time allowed by the stoplights. Minimum standards based upon community- living activities: The ability to walk 300 m (1000 feet) in less than 11.5 minutes (walking speed of 0.45 m/sec or 1 mph). The ability to walk at a speed of 1.3 m/sec (3 mph) for 13 to 27 m (42 to 85 feet) to cross a street safely. Dr. Michael P. Gillespie

HESITANCY CROSSING THE STREET https://www.youtube.com/watch?v=lc32tnYCe1E Dr. Michael P. Gillespie

GAIT CYCLE Stance Phase = 60% of gait cycle Swing Phase = 40% of gait cycle Dr. Michael P. Gillespie

SUBDIVISION OF THE GAIT CYCLE 15-10 Dr. Michael P. Gillespie

GAIT CYCLE: BREAKDOWN OF COMPONENTS https://www.youtube.com/watch?v=5j4YRHf6Iyo Dr. Michael P. Gillespie

SUBDIVISION OF STANCE AND SWING PHASES Five specific events are typically described during stance phase: Heel contact Foot flat Mid stance Heel off (heel rise) Toe off Three specific events are typically described during the swing phase: Early swing Mid swing Late swing Dr. Michael P. Gillespie

STANCE PHASE Heel contact – the instant the heel comes in contact with the ground (occurs at 0% of the gait cycle). Foot flat – the instant the entire plantar surface of the foot comes in contact with the ground (occurs at approximately 8% of the gait cycle). Mid stance – the point at which the body’s weight passes directly over the supporting lower extremity. The point when the foot of the lower extremity in the swing phase passes the lower extremity in the stance phase (feet are side by side). (occurs at 30% of the gait cycle or 50% of the stance phase) Heel off (heel rise) – the instant the heel comes off the ground (occurs between 30% and 40% of the gait cycle). Toe off – the instant the toes come off the ground (occurs at 60% of the gait cycle). Dr. Michael P. Gillespie

PUSH OFF A period referred to as push off is also often used. This period roughly corresponds to the movement of ankle plantar flexion at 40% to 60% of the gait cycle. Dr. Michael P. Gillespie

SWING PHASE Early swing – the period of time from the time of toe off to mid swing (60% to 75% of the gait cycle). Mid swing – the time from slightly before to slightly after the mid stance event of the opposite lower extremity, when the foot of the swing limb passes next to the foot of the stance limb (75% to 85% of the gait cycle). Late swing – the period from the end of mid swing to foot contact with the ground (85% to 100% of the gait cycle). Dr. Michael P. Gillespie

TERMINOLOGY DEFINING SUBDIVISIONS OF GAIT CYCLE Phases Events Percentage of Cycle Events of Opposite Limb Stance Heel Contact Foot Flate Mid Stance Heel Off Toe Off 8 10 30 30-40 50 60 Mid swing (25%-35%) Swing Early Swing Mid Swing Late Swing 60-75 75-85 85-100 90 100 Mid-stance (80%) Heel off (80-90%) Dr. Michael P. Gillespie

GAIT CYCLE - PERRY 8 events 7 Periods Dr. Michael P. Gillespie

EVENTS OF GAIT CYCLE - PERRY Initial contact Opposite toe off Heel rise Opposite initial contact Toe off Feet adjacent Tibia vertical Dr. Michael P. Gillespie

PERIODS OF GAIT CYCLE - PERRY Stance phase Loading response mid stance Terminal stance Pre swing Swing phase Initial swing Mid swing Terminal swing Dr. Michael P. Gillespie

EVENTS OF GAIT CYCLE 15-12 Dr. Michael P. Gillespie

NORMAL GAIT https://www.youtube.com/watch?v=VYVyoFdJHd U Dr. Michael P. Gillespie

ABNORMAL GAIT https://www.youtube.com/watch?v=pnMpHwBCl w8&index=3&list=PLt9rbdWnb3kjThf6oUGhdrd 6TcNpYFgU2 Dr. Michael P. Gillespie

DISPLACEMENT AND CONTROL OF THE BODY’S CENTER OF MASS Walking can be described as a series of losses and recoveries of balance. Ambulation is initiated by allowing the body to lean forward. For a fall to be prevented, momentary recovery of balance is achieved by moving either foot forward to a new location. Once gait is initiated, the body’s forward momentum carries the center of mass (CoM) of the body beyond the foot’s new location, necessitating a step forward with the other foot. Ambulation stops when foot placement stops the forward momentum of the body. Dr. Michael P. Gillespie

DISPLACEMENT OF THE CENTER OF MASS The body’s center of mass (CoM) is located just anterior to the second sacral vertebra, but the best visualization of the movement of the CoM is by tracking the displacement of the head or torso. The most notable displacement of the body during gait is in the forward direction; however, displacement also occurs in the vertical and side- to-side directions. Dr. Michael P. Gillespie

DISPLACEMENT OF CENTER OF MASS Total Vertical Displacement: 5 cm Total side-to-side displacement: 4 cm Dr. Michael P. Gillespie

CENTER OF MASS DISPLACEMENT 15-13 Dr. Michael P. Gillespie

TRANSFER BETWEEN KINETIC AND POTENTIAL ENERGY DURING GAIT 15-14 Dr. Michael P. Gillespie

EXCESSIVE DROP OF ILIAC CREST FROM WEAK GLUTEUS MEDIUS 15-18 Dr. Michael P. Gillespie

INCREASED ENERGY COST OF WALKING WITH SPECIFIC CONDITIONS 15-4 Immobilization of one ankle 3-6 Immobilization of one knee in full extension 23-33 Immobilization of one knee at 45 degrees of flexion 37 Immobilization of one hip, arthrodesis 32 Unilateral transtibial amputation, walking with prosthesis 20-38 Unilateral transfemoral amputation, walking with prosthesis 20-60 Postcerebrovascular accident 55 Dr. Michael P. Gillespie

PATH OF THE CENTER OF PRESSURE 15-32 Dr. Michael P. Gillespie

GAIT DYSFUNCTIONS Dr. Michael P. Gillespie

CAUSES OF PATHOLOGIC GAIT PATTERNS Pain Central Nervous System Disorders Musculoskeletal System Impairments Dr. Michael P. Gillespie

ANKLE PLANTAR FLEXION CONTRACTURE Dr. Michael P. Gillespie

WEAK ANKLE DORSIFLEXORS Dr. Michael P. Gillespie

EXCESSIVE ANKLE PLANTAR FLEXION Dr. Michael P. Gillespie

WEAK QUADRICEPS LEADING TO ANTERIOR TRUNK LEAN Dr. Michael P. Gillespie

KNEE FLEXION CONTRACTURE RESULTING IN CROUCHED GAIT OF THE STANCE LIMB Dr. Michael P. Gillespie

HIP CIRCUMDUCTION DURING SWING Dr. Michael P. Gillespie

ATAXIC GAIT DEMONSTRATION The patient's gait is wide-based with truncal instability and irregular lurching steps which results in lateral veering and if severe, falling. This type of gait is seen in midline cerebellar disease. It can also be seen with severe lose of proprioception (sensory ataxia) https://www.youtube.com/watch?v=FpiEprzObIU &list=PLCB588B387FB08409 Dr. Michael P. Gillespie

NORMAL AND ABNORMAL GAIT SERIES https://www.youtube.com/playlist?list=PLt9rbdW nb3kjThf6oUGhdrd6TcNpYFgU2 Dr. Michael P. Gillespie