upper extremities parts shoulder girdle shoulder joint elbow joint radioulnar joint wrist joint
TRANSCRIPT
Upper Extremities Parts
Shoulder GirdleShoulder JointElbow JointRadioulnar JointWrist Joint
Muscle Contribution to Joint
Stronger Muscles = More Joint Stability
Angles of Pull influence Joint Stability
Stabilizing Angles = < 90 angle of pull
Dislocating Angles = > 90 angle of pull
Shoulder Girdle
Involved in Reaching/Grasping MotionsDesigned for MobilityUnstable jointStrength of Muscles VERY important
Shoulder JointInvolved in a wide variety of motionsDesigned for Mobility, Unstable jointRotator Cuff & Deltoids = small angle pullWheel-Axle Mechanism
Overarm Throw Pattern
“cocking action” = extreme lateral rotation
rapid medial rotation and protraction
Strengthen Medial Rotators BOTH Concentrically and Eccentrically
Elbow Joint
Only Flexion and Extension
Stable joint due to bony structure
Muscle arrangement = stabilizing effect
How to Strengthen Elbow Extensors
Elbow Extensions with Elbow Extensions with shoulder flexed shoulder flexed figure 2.5e on page 61figure 2.5e on page 61
Shoulder Shoulder Hyperextensions with elbow Hyperextensions with elbow extended extended figure 2.5d on page 61figure 2.5d on page 61
3 Ways to Strengthen Elbow Flexors
1.1. Elbow flexion from Elbow flexion from anatomical positionanatomical position
2.2. Elbow flexion with Elbow flexion with shoulder Hyperextendedshoulder Hyperextended
3.3. shoulder flexionshoulder flexion figure 2.5j on pg 62 figure 2.5j on pg 62
Radioulnar Joint
Unstable due to weak bony arrangementPronate = turn inward [medial] away from
anatomical positionSupinate = turn outward [lateral] back
toward anatomical position
figure 5.12 figure 5.12 left side of picture left side of picture pronatedpronatedpage 185 page 185 right side of picture right side of picture supinatedsupinated
Wrist Joint
MSDs - musculoskeletal disorders1. angle of the work surface2. position requirements of the work 3. magnitude & direction of applied forces4. Degree of repetition
CTS - Carpal Tunnel Syndromesee Force guidelines per task on page 189
Hip JointMedial rotation involved in kick, throw & strikeWheel-Axle - figure 6.5 and 6.6 [page 197]
A: medial B: lateral hip rotation
Hip JointBending/Stooping = increase FA resistiveto achieve equilibrium, hip extensors must
provide high Tension/Force [hams, back]
FIG 9-30 page 296
“Basic Biomechanics”4th Edition
by Susan J. Hall
Knee Joint
• Biarticulate Muscles - work knee and hip• Muscular Imbalances:
1. Hams - lateral vs. medial lateralis2. Quads - vastus lateralis and medialis
• Positions for potential injury1. Foot fixed while hip/trunk rotates2. Squats [FIG 6.11 pg 204] 3. Whip kick in Breaststroke [FIG 6.12 pg 205]
Knee Joint: Potential Injury Positions
page 205
Knee Joint: Potential Injury Positions
turning the bodywhile foot is fixed
FIG 6.8 page 200
Knee Joint: Potential Injury Positions
Deep Squat
changing axis of rotation
from knee jointto
calf/thigh area
FIG 6.11 page 204
Knee Joint: Potential Injury Positionsrehabilitation of knee injuries
page 260: studies on ACL stress, shear forces, petellofemoral contact
ANKLE JOINTBony arrangement = stabilityLigaments play major role in stability
flexion = dorsiflexionextension = plantar flexion
FIG 6.13page 207
SUBTALAR JOINT
allows foot to navigate uneven surfacesinversion (sole in) and eversion (sole out)inversion with plantar flexioneversion with dorsiflexion
FIG 6.15page 209
Inversion during Plantar Flexion
Muscles of Ankle & Foot
Strength important on all sidesMuscular imbalance = misalignmentmisalignment = line of g eccentric to jointsweak dorsiflexors may cause shin splintsoverdeveloped inversion/plantar flexion muscles
= prone to lateral ankle sprains
Stretching Achilles Tendon
Preventative measure for shin splints
Achilles tendon = extension of both gastrocnemius and soleus muscles
2 dorsiflexion stretches:1. with knee extended2. with knee flexed
Plantar Fasciitis
Overuse Syndrome injury
overload of stress at insertion of plantar surface fascia on calcaneous
chronic therapy involves:1. Strengthen plantar & dorsiflexors2. Increase ROM in dorsiflexion
see page 210 re Kibler et al study
LOCOMOTION Walking Running
Long support phase [65%]
always support phase
Shorter support phase
non-support phase
F vertical = 3 x body wt
Ideal Alignments: LEG
Lower extremities like columns supporting a roof
Ideally as vertically aligned and as straight as possible to support the forces from above
FIG 6.19page 213
Ideal Alignments: FOOT
FIG 6.20page 214
a is Ideal FIG 6.21
Leg Length Inequities
Anatomical - due to bone structure
Functional - due to tilted pelvis
Environmental - due to uneven ground
TORSION Femoral Tibial
Femur rotated medialmedial facing patella frequent in FEMALES treatment:1. Strengthen lateral hip
rotators2. Stretch medial hip
rotators
Tibia rotated laterallateral facing patellafrequent in MALEStreatment: - muscular balance in all
3 hamstrings must be developed
VARUS INWARD angle INWARD angle from proximal to from proximal to distaldistal
lateral stress is lateral stress is proximalproximal
medial stress is medial stress is distal distal
VALGUS OUTWARD angle OUTWARD angle from proximal to from proximal to distaldistal
medial stress is medial stress is proximalproximal
lateral stress is lateral stress is distaldistal
Key Features of Good Shoes
Heel well cushionedHeel Counter firmArch Support firmSole Width reasonable for stabilityForefoot flexible & cushionedToe Box with reasonable roomTraction, Durability, Permeability