OVERALL: Great Job on Video Exam Median: 74% (half of the class scored 71% or higher) Mean: 74% (class average) 72% of class scored 70% or higher 31% of class scored 80% or higher 50% of class improved over October Mid-Term grade Those that did not do as well as expected let’s get together to see what happened and move onward & upward

Upper Extremities Parts Shoulder Girdle Shoulder Joint Elbow Joint Radioulnar Joint Wrist Joint

Types of Synovial Joints from “Basic Biomechanics” by Susan Hall page 121

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 Motions Designed for Mobility Unstable joint Strength of Muscles VERY important

Shoulder Joint Involved in a wide variety of motions Designed for Mobility, Unstable joint Rotator Cuff & Deltoids = small angle pull Wheel-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 shoulder flexed figure 2.5e on page 61 Shoulder Hyperextensions with elbow extended figure 2.5d on page 61

3 Ways to Strengthen Elbow Flexors Elbow flexion from anatomical position Elbow flexion with shoulder Hyperextended shoulder flexion figure 2.5j on pg 62 

Radioulnar Joint Unstable due to weak bony arrangement Pronate = turn inward [medial] away from anatomical position Supinate = turn outward [lateral] back toward anatomical position figure 5.12 left side of picture pronated page 185 right side of picture supinated

Wrist Joint MSDs - musculoskeletal disorders 1. angle of the work surface 2. position requirements of the work 3. magnitude & direction of applied forces 4. Degree of repetition CTS - Carpal Tunnel Syndrome see Force guidelines per task on page 189

Hip Joint Medial rotation involved in kick, throw & strike Wheel-Axle - figure 6.5 and 6.6 [page 197] A: medial B: lateral hip rotation

Hip Joint Bending/Stooping = increase FA resistive to achieve equilibrium, hip extensors must provide high Tension/Force [hams, back] FIG 9-30 “Basic Biomechanics” 3rd Edition by Susan J. Hall

Knee Joint Biarticulate Muscles - work knee and hip Muscular Imbalances: 1. Hams - lateral vs. medial lateralis 2. Quads - vastus lateralis and medialis Positions for potential injury 1. Foot fixed while hip/trunk rotates 2. 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 body while foot is fixed FIG 6.8 page 200

Knee Joint: Potential Injury Positions Deep Squat changing axis of rotation from knee joint to calf/thigh area FIG 6.11 page 204

Knee Joint: Potential Injury Positions rehabilitation of knee injuries page 260: studies on ACL stress, shear forces, petellofemoral contact