Functional stages in AMN United Leukodystropphy Foundation July 19, 2013 Kathy Zackowski, PhD, OT Motion Analysis Laboratory Kennedy Krieger Institute Johns Hopkins University School of Medicine What we know: Central nervous system changes Our past studies show • Sensory loss (vibration) feet >> hands • Progressive weakness legs >> arms secondary disuse • Spasticity, legs • Difficulty walking • Poor balance This is what we did: Purpose: To quantify symptom characteristics of AMN in men and women and determine which characteristic(s) have the greatest impact on function. Subjects: 60 men, 80 women with AMN • Single test session • In the motion analysis laboratory at Kennedy Krieger • Clinical exam • Individualized exercise program What impairment effects movement performance most? Functional Tests Impairments Vibration sensation Range of motion Static Balance Dynamic Balance Strength Walking Speed Age Walking endurance Sit to Stand Gravity Lessened Antigravity Resistive Demographics Variable Men Women Strength group Gravity Lessened Anti-gravity Resistive Gravity Lessened Anti-gravity Resistive Flexor strength, kg 2.0 15.6 24.3* 0 11.2 17.0* Sample size 5 24 31 2 25 53 Age, y 39 41 40 50 54 44 Vibration 19.9 13.3 10.4 19.9 8.4 6.0 Ankle DF ROM -7 2 7 -4 2 7 *40 y/o male norm: 29.0 kg *50 y/o female norm: 18.1 kg Sit to Stand slower Standing Balance: eyes open feet apart Men 40% 91% Gravity Lessened 100% Anti-gravity 100% 94% Resistive 100% Women Percentage values are those per group able to stand for 20 seconds Standing Balance: eyes closed feet together Men 26% 83% Gravity Lessened Anti-gravity Resistive 50% 96% Women Percentage values are those per group able to stand for 20 seconds Dynamic Standing Balance slower slower slower Endurance Exercises must match your ability Gravity Lessened Antigravity Resistive Strength can be improved over one year Women (kg) Strength(lbs) ExtensionStrength Hip HipExtension Hip Extension 18.0 40.0 16.0 35.0 14.0 30.0 12.0 25.0 10.0 20.0 8.0 15.0 6.0 10.0 4.0 5.0 2.0 0.0 Exercse Group Control Group 0 1 (kg) Strength(lbs) ExtensionStrength Knee KneeExtension Visit Knee Extension 70.0 30.0 60.0 25.0 50.0 20.0 40.0 15.0 30.0 10.0 20.0 5.0 10.0 Exercse Group Control Group 0.0 0 1 Visit Men (kg) Strength(lbs) ExtensionStrength Hip HipExtension Hip Extension 50.0 25.0 40.0 20.0 30.0 15.0 Exercse Group 20.0 10.0 Control Group 10.0 5.0 0.0 0 1 (kg) Strength(lbs) ExtensionStrength Knee KneeExtension Visit Knee Extension 45.0 90.0 80.0 40.0 70.0 35.0 60.0 30.0 50.0 25.0 40.0 20.0 30.0 15.0 20.0 10.0 10.0 5.0 0.0 Exercse Group Control Group 0 1 Visit Functional Measures Get Up And Go Time (s) Velocity (m/s) Velocity 1.5 1 Men 0.5 Women 0 0 1 Visit Get Up And Go 15 10 5 Men 0 Women 0 1 Visit EOFA Standing Amplitude (mm) 4 3 2 Men 1 Women 0 0 1 Visit 15 10 5 Men 0 Women 0 600 400 Men 200 Women 0 0 1 Visit 1 Visit 6-Min Walk Distance Distance (m) Sit To Stand Time (s) Sit To Stand Summary • Of all the impairments, weakness is the most prevalent feature effecting movement performance • Weakness affects both men and women • Strength varies from person to person • Preliminary data shows strength is changeable • Important to individualize an exercise program Acknowledgements Neurogenetics: Jerry Raymond Kim Hollandsworth Katy Gibbons Lena Bezman Motion Analysis Lab: Jennifer Keller Rhul Marasigan Joe Wang * All the people with AMN (and their families) who enthusiastically participated in this study