Biomechanical Framework PDF

Framework: biomechanical framework Guides with restorative care Examples Treating a tissue or structural anomaly that can be restored to its original form: Restoring strength through isometric exercises for immobilized functions, such as performing isometric wall pushes for k...

Framework: biomechanical framework Guides with restorative care Examples Treating a tissue or structural anomaly that can be restored to its original form: Restoring strength through isometric exercises for immobilized functions, such as performing isometric wall pushes for knee rehabilitation after an injury. Treatment Enabling activities: Activities designed to enhance engagement in daily life, such as practicing self-feeding techniques for individuals recovering from a stroke. Sensorimotor techniques: Activities that engage both sensory and motor functions, such as using textured balls for grip strength and sensory feedback. Graded exercises: Incrementally increasing the intensity of exercises, for instance, starting with light resistance bands and progressing to heavier weights for strength training. Physical agent modalities as a preparatory task: Using ultrasound therapy or electrical stimulation to prepare muscles before engaging in physical therapy sessions. Manual techniques: Hands-on approaches, such as joint mobilization or soft tissue massage, to improve range of motion or relieve pain. Occupations as means can be utilized but must be tailored to an individual’s capacities and goals, for example, adapting gardening tasks for someone with limited mobility to encourage engagement. Framework: Rehabilitation framework Examples (PEO) Altering or changing the occupation/activity/task: Modifying a cooking activity by using adaptive tools for someone with limited dexterity, like using a rocker knife. Adapting the task object: Changing the grip on a toothbrush for someone with arthritis to make it easier to hold. Changing the context: Facilitating a community outing in a wheelchair-accessible van for individuals with mobility challenges. Adapting to the environment: Adjusting the home setting with grab bars and non-slip mats for individuals recovering from surgery. Using people in the environment to aid in engagement: Involving family members in therapy sessions to support social interaction and motivation during recovery. Essentials of movement Muscles: Skeletal muscle is under voluntary control, enabling activities like walking or lifting weights. Connective tissue: Connective tissue, including tendons and ligaments, supports the musculoskeletal system.  Fascia: Wraps around muscles (in parallel) and connects to tendons (in series). For example, the fascia helps stabilize muscles during movements like running. Fascia provides structural stability for muscles: When lifting weights, fascia helps transmit force from muscles to bones via tendon insertion. Responsible for passive tension in force production: As the muscle lengthens, the fascia helps maintain tension, contributing to effective force production. Connective tissue Cartilage: Acts as a flexible shock absorber, like the meniscus in the knee, which deforms to moderate loads during activities like jumping. With rapid loads, it becomes stiff: For example, during a sudden impact, cartilage can resist compression forces, providing stability to joints. Hyaline cartilage has no vascular supply: It requires compressive forces for nutrition, as seen in the articular cartilage of joints where synovial fluid supplies nutrients. Buckles with compressive, heavy loads: For instance, during weightlifting, if the load exceeds the cartilage's capacity, it may lead to damage or injury. Essentials of movement Bone: Adaptive modeling: With compressive forces (stress), like weight-bearing exercises, stimulate bone remodeling, which strengthens the bone structure. It supports muscle and tendon attachments: For example, the femur serves as an attachment point for various muscles, facilitating leg movements. It lends itself to a system of rigid levers and pulleys: The bones act as levers in the body’s movement system, like the arm during a bicep curl. Its structure determines the type of movement available: The shape of the hip joint allows for a wide range of motion compared to the elbow joint. It allows for accessory movement: Passive movements, such as joint mobilization techniques performed by therapists, enhance range of motion without active muscle engagement. Ex: Passive stretching of the hamstrings while lying on a treatment table to improve flexibility without muscle contraction. Nervous system  Kinematics Definition: Kinematics is the study of movement between two adjoining bones, focusing on the motions without considering the forces that cause them. Types of Kinematics: Voluntary Movement: o Movement that is consciously controlled by an individual, such as raising an arm or bending a knee. Two Elements of Kinematics: o Osteokinematics: Refers to the voluntary joint movements of bones relative to each other. Example: Flexion and extension of the elbow or knee joint during movement. o Arthrokinematics: Involves the involuntary movements occurring at the joint surfaces during osteokinematic motion. Example: Rolling of the femoral head in the acetabulum during hip flexion. Osteokinematics Definition: Joint movements that are voluntary and can be described in terms of planes and axes of movement. Planes of Movement: o Sagittal Plane: Divides the body into left and right (e.g., flexing the elbow). o Frontal Plane: Divides the body into front and back (e.g., spreading fingers apart). o Transverse Plane: Divides the body into top and bottom (e.g., rotating the torso). Axes of Movement: o Medio-lateral axis: Associated with sagittal plane movements (e.g., flexion and extension).  o Anterior-posterior axis: Associated with frontal plane movements (e.g., abduction and adduction). o Vertical axis: Associated with transverse plane movements (e.g., rotation). Kinematic Chains Open Kinematic Chain: o Definition: Movements that are highly variable and involve distal segments moving freely in space. o Example: Performing a leg extension on a leg extension machine, where the foot is not fixed to a surface. o Risks: Unskilled movements can lead to injuries due to instability. Closed Kinematic Chain: o Definition: Movements that are predictable and involve fixed distal segments, resulting in more stable joint mechanics. o Example: Squatting, where the feet are planted on the ground. o Characteristics: Provides power and strength for functional movements, such as standing up from a seated position. Arthrokinematics Definition: Involuntary movements occurring at the joint surfaces during active movement. Key types include rolling, sliding, and spinning. Active Movement: Movement initiated by muscle contraction, such as lifting an arm overhead. Convex-Concave Rule: Describes how the surface shapes affect joint movement. For example, when the convex surface of a joint moves on a fixed concave surface, it rolls and slides in opposite directions. Passive Movement (Joint Play): Movement with an external force applied, such as a therapist moving a patient’s arm to assess joint mobility. Importance of Joint Play: Essential for maintaining joint health and function. Without adequate joint play, stiffness and pain can occur. Open Pack vs. Closed Pack Positions Closed Pack Position: o Definition: Position of maximal articular congruency (maximum fit), where ligaments and joint capsules are taut.  o Example: Full extension of the knee joint. o Injury Risk: Injuries often occur in this position due to the high stability but low mobility. Open Pack Position: o Definition: Opposite of closed pack; less joint congruency, allowing for more mobility. o Example: The shoulder in a relaxed position. o Application: Joint mobilization is typically performed in this position to improve mobility. Significance of Addressing Arthrokinematics Joint Mobilization: Restores the dynamics available at the joint, enhancing range of motion and reducing pain. Kinetics: Forces Definition: The study of forces as they relate to movement. Force Systems: Understanding how different force systems interact is crucial for analyzing movement. o Collinear Forces: Forces acting along the same line. ▪ Example: Two people pushing a car in the same direction. o Parallel Forces: Forces acting in the same or opposite directions but not along the same line. ▪ Example: Two parallel forces acting on a beam. o Concurrent Forces: Forces that meet at a common point. ▪ Example: Two people pulling on a rope from different directions. o Force Couple: A pair of forces that are equal in magnitude, opposite in direction, and work together to create stability or movement. ▪ Example: The forces created by the biceps and triceps during arm movements. Effects of Forces Displacement: Refers to the change in position caused by applied forces. o Static Equilibrium: Occurs when the sum of forces equals zero, resulting in no displacement. Types of Displacement: o Translatory Displacement: Linear movement in a straight line (e.g., sliding down a slide). o Rotatory (Angular) Displacement: Movement around an axis (e.g., rotating the arm). Torque: Causes rotary movement, calculated as:  T=Force×Perpendicular distance from the axis of rotation to the line of pullT = \text{Force} \times \text{Perpendicular distance from the axis of rotation to the line of pull}T=Force×Perpendicular distance from the axis of rotation to the line of pull o Example: Using a wrench to tighten a bolt. Stress: Resistance to Forces Temporary vs. Permanent Stress: Temporary stress may cause temporary deformation, while permanent stress results in lasting changes in structure. Types of Forces Causing Deformation Compressive Forces: o Definition: Forces that increase pressure. o Example: Pressure sores and fractures resulting from excessive weight on a body part. Tensile Forces: o Definition: Forces that stretch and pull apart. o Example: Muscle sprains caused by overstretching. Shear Forces: o Definition: Forces that cause two surfaces to slide past each other, resulting in torque. o Example: Fractures, muscle strains, and tears from abrupt movements. Friction Definition: The resistance that occurs when two forces come into contact, which can stabilize or cause injury. Forces: Simple Machines Pulleys: o Definition: Change the direction of pull and increase the moment arm. o Examples in the Body: ▪ Knee: Quadriceps muscle acting on the patella. ▪ Shoulder: Rotator cuff muscles. Inclined Planes: o Definition: Assist in moving loads more efficiently due to the distribution of load. o Example: Ramps used for wheelchair access. Levers:  o Definition: Can favor strength or distance. o Mechanical Advantage (MA): ▪ MA=EARAMA = \frac{EA}{RA}MA=RAEA (Effort Arm/Resistance Arm) ▪ MA = 1: The body is in equilibrium. ▪ MA > 1: Favors effort (EA > RA). ▪ MA < 1: Favors distance and speed (RA > EA). ▪ Example: The biceps brachii acting as a third-class lever during elbow flexion. Types of Levers 1st Class Lever: o Definition: The axis (or pivot) is located between the effort and load. o Example: The neck muscles lifting the head, where the pivot is the atlanto-occipital joint. 2nd class lever Resistance (load) is in between the effort and the axis EX: Heel raises in standing FEX EA = FRX RA Muscle effort x FA =Weight of body x RA The effort needed is less than the resistance that it is counteracting o This lever provides the muscle with a good mechanical advantage o Distance is compromised -The muscle force can move the body only a small distance EX: Wheelbarrow 3rd class Effort in between axis and resistance FEX EA < FRX RA EA 1 less effort needed, but distances the load is moved is small M