Evaluation and Treatment of Movement Dysfunction: A Biomechanical Approach Research Theme Christopher M. Powers, PhD, PT, FAPTA Understanding injury mechanisms will lead to the development of more effective and efficient clinical interventions Applied Movement System Research What are the underlying causes of movement dysfunction? Patellofemoral Pain to Pathology Continuum How are movement impairments linked to pain, functional limitations & pathology? Abnormal movement Elevated joint loading Pain Pathology (bone & cartilage) What are the best strategies/approaches to change movement behavior? Open Chain Video of CKC femoral rotation Closed Chain Powers et al., JOSPT, 2003, Souza & Powers, JOSPT, 2009
Evaluation of Patella Cartilage Stress Using Finite Element Modeling Excessive femoral internal rotation increases patella cartilage stress Liao et al. Med Sci Sports Exerc, 2015 Farrokhi et al., Osteoarthritis & Cartilage, 2011 Possible changes in cartilage in response to abnormal and/or prolonged stress Decreased cartilage thickness Decreased cartilage volume Loss of proteoglycans Increased water content Patella Cartilage Thickness 3.5 3.0 PFP Control 2.5 2.0 mm 1.5 1.0 0.5 0.0 Farrokhi et al, Am J Sports Med, 2011 and Knee Kinematics are Associated with Pain and Function in Males & Females with PFP Nakagawa et al., Int J Sports Med, 2013 Peak internal rotation and hip adduction during a step down test were significant predictors of pain Peak hip adduction was a significant predictor of function Paradigm shift in the treatment of PFP Control to Improve Patella Tracking & Minimize Patellofemoral Loading Emphasis on gluteus maximus & medius
Clinical Practice Journal of Athletic Training, 2015 Archives Physical Medicine & Rehabilitation, 2014 Why Evaluate Movement Clinically? Most patients seek out a physical therapist care because of pain -Typically activity or movement related Abnormal movement patterns can cause lower extremity injury -Joint stress (bone & cartilage) -Soft tissue strain (ligament & tendon) -Muscle overuse Where does Movement Analysis Fit Within the Clinical Practice Model? Subjective exam What is the patient s chief complaint & history? Establish tissue source of pain Movement analysis Hypothesis driven clinical exam Driven by movement analysis findings Evaluation/Working diagnosis Establish plan of care Clinical Example: Runner with Lateral Pain Common Movement Impairments in Runners 1. Cross-over sign (Initial contact) 2. Dynamic knee valgus (Deceleration) 3. Dynamic knee varus (Deceleration) 4. Excessive hip adduction (Deceleration) 5. Excessive hip internal rotation (Deceleration) 6. Excessive pelvic drop (Deceleration) 7. Excessive foot pronation (Deceleration) 8. Limited hip and/or knee flexion (Deceleration) 9. Knee forward of toe (Deceleration) 10. Vertical or extended trunk (Deceleration) 11. Lateral trunk flexion (Deceleration) 12. Limited hip extension (Toe off) 13. Excessive vertical displacement of COM (Toe off)
Anterior View: Deceleration Initial contact-peak knee flexion Key Clinical Exam Findings: 1. Abductor weakness (32% deficit) 2. Contralateral hip flexor tightness (+30 Thomas Test) Evaluation: Quantifying Movement Impairments ACL Case Example 18 year old soccer athlete 7 months post-acl reconstruction Patella tendon autograft No pain, swelling, or instability Normal quadriceps and hamstring strength Adequate performance of a single limb squat Good triple hop distance Involved limb ~90% of uninvolved limb
Ready to Return to Sport? Ready to Return to Sport? Clinical Assessment of Movement Clinical Assessment of Movement Shock Absorption Strategy Pelvis Trunk Total Score 0 1 1 1 0 3 out of 10 total Adequate = 2 ; Borderline = 1 Inadequate = 0 Shock Absorption Strategy Pelvis Trunk Total Score 2 2 2 1 2 9 out of 10 total Adequate = 2 ; Borderline = 1 Inadequate = 0 Treatment: Strengthening or Movement Re-education? Changing Movement Behavior Bloomfield et al., J Sport Sci & Med, 2007
What Muscle Would you Strengthen? Gluteus Maximus: The Tri-planar Muscle Extensor Abductor External Rotator Knee Knee Strategy Frontal Sagi al Knee Strategy Sagi al Frontal Influence of Muscle Strength extensor weakness relative to quadriceps Quadriceps overuse Increased knee loading -Knee Moment Ratios Associated with -Knee Strength Ratios TMS Mapping Study Glutues Maximus vs. Vastus Lateralis VL:59.3 GM:43.0 Female Knee/ Strength Ratio Male: Knee/ Strength Ratio knee Only extensor17% of the hip extensor variance in movement behavior could be explained by strength knee extensor hip extensor VL : 18.8 GM: 63.5 Stearns & Powers, Med Sci Sport Exerc, 2013
Correlation of K-H Mapping Ratio vs. K- H Moment Ratio r =0.918 (p=0.081) Movement Training to Minimize Re- Injury Risk 2.5 Mapping Ratio vs. Moment Ratio Moment ratio 2 1.5 1 0.5 0 0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 Mapping Ratio Feedback: External Focus of Attention Stretch the band Land softly A Critical Element of Movement Re-education & Motor Learning Post-Response Feedback Knowledge of Results Concurrent Visual Feedback: Motion
Concurrent Visual Feedback: Force Concurrent Visual Feedback: EMG Questions/Comments?