Chapter 1: Introduction to Biomechanics

What Is Biomechanics?
Biomechanics is the science that applies principles of mechanics to the study of living
organisms, focusing especially on the structure and movement of the human body. In
physiotherapy, biomechanics helps understand how muscles, bones, tendons, and ligaments work
together to produce movement and maintain posture. Its goal is to improve physical
performance, prevent injuries, and guide rehabilitation through precise scientific
analysis.ftramonmartins.wordpress+2

Scope of Biomechanics
 Areas covered: Human movement, forces, motion analysis, injury mechanisms, and
rehabilitation science.ftramonmartins.wordpress
 Branches:
o Statics (study of bodies at rest and equilibrium)
o Dynamics (study of bodies in motion)
o Kinetics (forces causing movement)
o Kinematics (description of movement, i.e., displacement, velocity,
acceleration).elsevier+1

Importance for Physiotherapy

 Guides assessment of movement dysfunctions and musculoskeletal disorders.
 Informs design of therapeutic exercises and manual therapy techniques.
 Supports clinical decision-making for injury prevention and recovery.elsevier

Structure of Biomechanics
Diagram: Levels of Biomechanical Study
 Macro-level: Whole-body movements (walking, running, jumping)
 Micro-level: Movements at joints and muscles (elbow flexion, muscle contraction)
 System-level: Integration of anatomical systems in movement (skeletal, muscular,
nervous systems)somepomed
![Example biomechanical analysis diagram: showing bones, muscles, and force vectors in a
human limb during movement]ftramonmartins.wordpress

Historical Overview
 Emerged from classical mechanics and anatomy in the early 20th century.
 Developed through contributions from physics, engineering, medicine, and sports
science.ftramonmartins.wordpress
 Modern biomechanics uses advanced imaging, computer modeling, and electronics to
analyze movement and forces with great precision.somepomed

Fundamental Concepts
 Movement Analysis: Examining motion through measurement tools (video analysis,
force plates, EMG).
 Mechanical Laws: Newton’s laws applied to human motion—how force, mass, and
acceleration interact in the body.elsevier+1
 Clinical Relevance: The basis for understanding gait, posture, joint function, therapy
interventions, and assistive device design.

Summary
Biomechanics connects the principles of physics and engineering to human health and
movement. Its applications are crucial in physiotherapy to improve mobility, treat dysfunctions,
develop rehabilitation plans, and understand how activities and environments affect the body.
Throughout the book, anatomical structure, mechanical principles, and clinical applications will
be explored in depth, with diagrams illustrating every major concept for students.somepomed+2

Next Chapter Preview:

Chapter 2 will examine human anatomy in the context of biomechanics, beginning with bones,
joints, and muscle structure, and how each anatomical feature contributes to human motion.

Practice Questions:

1. Define biomechanics and its relevance to physiotherapy.

 2. Differentiate between statics and dynamics using human movement examples.
3. Name three technological tools used for biomechanical assessment in the clinic.

Glossary:

 Biomechanics
 Statics
 Dynamics
 Kinematics
 Kinetics
 Rehabilitation

Chapter 2: Human Anatomy for Biomechanics

Overview
An understanding of human anatomy is essential for biomechanics as it explains how bones,
joints, and muscles contribute to movement and load bearing. This chapter will focus
on:somepomed+1

 Structure and function of bones

 Types of joints and their mechanics
 Muscular system and muscle types
 Anatomical terminology related to movement

Bones
 Function: Provide structural support, protect organs, enable movement by acting as
levers, and store minerals.ftramonmartins.wordpress
 Types of Bones:
o Long bones (e.g., femur, humerus)
o Short bones (e.g., carpals)
o Flat bones (e.g., scapula)
o Irregular bones (e.g., vertebrae)
 Bone Structure:
o Diaphysis (shaft)
o Epiphysis (ends)
o Medullary cavity
o Compact vs spongy bone.somepomed+1
 Diagrams: Bone anatomy with labels for key parts, and cross-sectional views.
Joints
 Types of Joints:
o Immovable (fibrous) e.g., skull sutures
o Slightly movable (cartilaginous) e.g., vertebral discs
o Freely movable (synovial) e.g., knee, shoulder.ftramonmartins.wordpress
 Synovial Joint Structure: Capsule, synovial membrane, ligament, cartilage, synovial
fluid.
 Joint Movements:
o Flexion, extension
o Abduction, adduction
o Rotation, circumduction
 Articular Cartilage & Stability: Function in shock absorption and stability.
 Measuring Range of Motion (ROM): Use of goniometers and importance for
physiotherapy.ftramonmartins.wordpress
 Diagrams: Types of joints and joint movement planes illustrated.

Muscular System
 Types of Muscles:
o Skeletal (voluntary, striated)
o Smooth (involuntary)
o Cardiac (heart muscle)
 Muscle Structure: Muscle fibers, fascicles, connective tissues.
 Muscle Contractions:
o Isometric (no length change)
o Isotonic (length change, concentric/eccentric).somepomed+1
 Force Production: Motor units, muscle spindle, and neuromuscular junction basics.
 Diagrams: Muscle fiber anatomy, contraction cycle, and force production.

Anatomical Terms for Movement

 Planes: Sagittal, frontal (coronal), transverse.
 Axes: Anteroposterior, mediolateral, longitudinal.
 Body Positions and Directional Terms: Superior, inferior, anterior, posterior, medial,
lateral.
Summary
This chapter establishes the essential anatomical basis necessary for studying biomechanics. It
details how bones and joints function as mechanical structures and how muscles generate forces
to produce movement. The included diagrams will aid in visualizing these components and their
roles in human biomechanics.

Next Chapter Preview:

Chapter 3 will explore mechanical principles such as forces, levers, torque, and motion analysis
relevant to human movement.

Practice Questions:

1. Name and describe the three types of joints.

2. What are the functions of bones in biomechanics?
3. Explain the difference between isotonic and isometric muscle contractions.

Glossary:

 Diaphysis
 Epiphysis
 Synovial joint
 Range of motion (ROM)
 Isometric contraction
 Isotonic contraction

Chapter 3: Mechanical Principles in Biomechanics

Overview
This chapter covers the fundamental mechanical principles that govern human movement,
essential to physiotherapy practice. It explains how forces interact with the body to produce
motion, maintain balance, and enable everyday activities.australiansportsphysio+2

Key Mechanical Concepts

Force and Motion Principle
 Forces cause or change movement. Internal forces come from muscles; external forces
include gravity or external loads.
 An unbalanced force acting on a body leads to motion or acceleration (Newton’s 2nd
law).
 Example diagrams show force vectors acting on limbs during activities like walking or
lifting.sist.sathyabama+1

Force-Time Principle
 The duration over which a force is applied affects the resulting motion, not just the
magnitude.
 Applying force slowly or rapidly leads to different mechanical outcomes.

Range of Motion (ROM)

 ROM refers to the degree of movement around a joint—classified as linear or angular
motion.
 Increasing ROM can enhance speed or control during movement.
 Goniometers measure ROM in clinical settings.sist.sathyabama

Balance
 Balance is the ability to maintain the body’s center of mass over the base of support.
 Stability and mobility have an inverse relationship: the more stable, the less mobile and
vice versa.
 Diagram illustrating base of support, center of gravity, and line of gravity to explain
postural control.australiansportsphysio+1

Coordination Continuum
 Refers to how muscle actions and body segment motions are timed.
 Movements may be simultaneous or sequential—both types contribute to smooth,
effective motion.

Segmental Interaction
 The human body functions as a linked system of rigid segments.
 Forces can be transferred or modified through joints and links affecting overall motion.
Levers and Torque
 Levers consist of a fulcrum (joint), force (muscle), and load (resistance).
 Types of levers:
o First-class (e.g., neck extension)
o Second-class (e.g., calf raise)
o Third-class (e.g., biceps curl—most common in the body).copthnigadi+1
 Torque is the turning effect of a force applied at a distance from the fulcrum.
 Diagrams illustrate lever classes, force arms, and torque application in the body.

Practical Examples and Clinical Relevance

 Free-body Diagrams: Show forces and torques on specific joints during movement.
 Application of force and torque principles in designing therapeutic exercises.
 Understanding mechanical advantage helps optimize rehabilitation interventions.

Summary
Understanding these mechanical principles allows physiotherapists to assess and influence
human movement effectively. They form the scientific basis for evaluating posture, balance, and
gait, and for designing customized rehabilitation programs that restore function and prevent
injury.australiansportsphysio+1

Next Chapter Preview:

Chapter 4 will focus on kinematics and kinetics, elaborating on how movements are described
and analyzed in physiotherapy.

Practice Questions:

1. What is the principle of force-time, and why is it important?

2. Describe the three types of levers found in the human body.
3. Explain how balance affects mobility and stability.

Glossary:
  Force
 Torque
 Lever
 Stability
 Range of motion (ROM)
 Free-body diagram

Chapter 4: Kinematics and Kinetics in Biomechanics

Overview
Biomechanics studies human movement through two interconnected fields: Kinematics and
Kinetics. Understanding these concepts is essential for physiotherapy as they describe and
explain how and why the body moves.imeasureu+1

Kinematics
 Definition: Kinematics is the study of motion without considering the forces or causes
behind it.byjus+1
 Focus: Describes how an object moves using variables like:
o Displacement (change in position)
o Velocity (speed with direction)
o Acceleration (rate of change of velocity)
o Time
 Applications: Used to analyze body part movement, gait patterns, joint angles, and speed
of limb segments.futurelearn+1

Kinetics
 Definition: Kinetics studies the forces and torques that cause or change
motion.imeasureu+1
 Focus: Investigates the relationship between forces (muscular, gravitational, friction) and
motion produced.
 Applications: Helps understand how external forces like gravity and internal forces like
muscle contractions influence movement and stability.imeasureu

Key Differences: Kinematics vs Kinetics

 Aspect Kinematics Kinetics
Motion description (position, velocity,
Focus Forces causing motion
acceleration)
Concerned with Movement forms Causes of movement
Mass
No Yes
consideration
Muscle force, gravity,
Examples Measuring joint angles, speed
friction

Important Concepts in Kinematics

 Types of Motion:
o Linear (translation of body in straight line)
o Angular (rotation about an axis)
o Combined (most human movements)
 Planes and Axes:
o Sagittal, frontal, transverse planes.ftramonmartins.wordpress
o Movements like flexion, extension, abduction, adduction describe movement in
these planes.

Important Concepts in Kinetics

 Forces Affecting Motion:
o Muscle forces
o External forces (gravity, ground reaction forces)
o Joint reaction forces
 Torque:
o Turning force around a joint axis
 Free-body Diagrams: Visual representation of forces acting on a body segment

Clinical Significance
 Kinematic analysis helps assess movement efficiency, speed, and range.
 Kinetic analysis allows physiotherapists to estimate loads on joints and muscles to plan
rehabilitation exercises effectively.
 Both analyses are integrated during gait assessment and injury prevention programs.
Summary
Kinematics explains “what” motion is occurring, while kinetics explains “why” the motion
happens by examining forces. Together, they provide a complete understanding of human
movement crucial for clinical evaluation and physiotherapy practice.slideshare+1

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Chapter 5 will examine biomechanical aspects of human movement, including posture, balance,
and gait.

Practice Questions:

1. Define kinematics and list the variables it studies.

2. What forces are involved in kinetics?
3. Explain the role of torque in human movement.

Glossary:

 Kinematics
 Kinetics
 Displacement
 Velocity
 Acceleration
 Torque

Chapter 5: Biomechanics of Posture, Balance, and Gait

Overview
This chapter discusses how the human body maintains posture and balance and how it moves
through gait. These are fundamental aspects analyzed in physiotherapy to assess and improve
functional mobility and overall physical health.slideshare+2

Posture
 Definition: Posture is the alignment of body segments relative to each other and the
environment, maintained with minimal energy expenditure.
  Types: Static posture (standing or sitting) and dynamic posture (during movement).
 Biomechanical Principles:
o The body’s center of gravity (COG) must be maintained within the base of
support (BOS) for stability.
o Proper alignment reduces stress on muscles, ligaments, and joints.slideshare
 Postural Deviations: Kyphosis, lordosis, scoliosis—result from muscular imbalances or
structural changes.
 Assessment Tools: Visual observation, plumb line, force platforms.

Balance
 Definition: The ability to maintain the body’s center of mass over its base of support
both statically and dynamically.
 Types:
o Static balance (while stationary)
o Dynamic balance (during movement)
 Mechanisms Involved:
o Sensory inputs: Visual, vestibular, proprioceptive
o Motor responses: Muscle strength and coordination
 Balance Strategies: Ankle, hip, and stepping strategies to recover equilibrium.
 Clinical Importance: Balance impairment is a major fall risk factor.

Gait
 Definition: Gait is the pattern of movement of the limbs during locomotion.
 Phases of Gait Cycle:
o Stance phase (about 60%): When the foot is on the ground.
o Swing phase (about 40%): When the foot is in the air moving forward.
 Determinants of Normal Gait:
o Pelvic rotation and tilt
o Knee flexion in stance phase
o Foot and ankle movement
 Gait Parameters: Step length, stride length, cadence, speed.
 Biomechanical Analysis:
o Study of joint angle changes, forces, and muscle activity.
o Use of instrumentation like force plates and motion capture.

Clinical Applications
  Diagnosing movement disorders and musculoskeletal conditions.
 Planning rehabilitation exercises targeting postural correction and gait training.
 Evaluating effectiveness of orthotic and prosthetic devices.
 Preventing falls and improving functional independence.

Diagrams Suggested
 Body alignment and center of gravity with base of support.
 Gait cycle phases with joint angles.
 Balance mechanisms schematic (sensory inputs and motor responses).

Summary
Understanding posture, balance, and gait biomechanics is vital for physiotherapists to evaluate
movement efficiency and develop targeted interventions. This chapter builds the foundation for
clinical assessments and therapeutic strategies improving mobility and safety.now.aapmr+2

Next Chapter Preview:

Chapter 6 will explore clinical applications of biomechanics in physiotherapy, including
rehabilitation principles and injury management.

Practice Questions:

1. What factors maintain balance during standing and movement?

2. Describe the major phases of the gait cycle.
3. How does posture affect biomechanical efficiency?

Glossary:

 Posture
 Balance
 Gait cycle
 Stance phase
 Swing phase
 Center of gravity (COG)
Chapter 6: Clinical Applications of Biomechanics in Physiotherapy

Overview
Biomechanics plays a critical role in physiotherapy by helping clinicians understand the
mechanical interactions within the body and applying this knowledge to diagnose, treat, and
rehabilitate musculoskeletal conditions and injuries. It enhances patient care by optimizing
functional recovery and preventing future injuries.clinicsearchonline+2

Biomechanics in Rehabilitation
 Assessment: Use of motion analysis, force plates, electromyography (EMG), and video
systems to evaluate movement, muscle activation, joint loading, and functional
deficits.noraxon
 Personalized Treatment: Tailoring rehabilitation exercises based on biomechanical
deficits such as range of motion limitations, muscle imbalances, and altered gait
patterns.noraxon
 Progressive Exercise Programs:
o Gradually increasing intensity and complexity
o Incorporating cross-functional, real-life movement patterns to improve daily
activity performance
o Avoiding overload in vulnerable tissues to prevent re-injury.noraxon
 Patient Education: Explaining biomechanical principles to patients enhances
compliance and motivation.

Applications in Orthopedics
 Joint Kinematics and Dynamics: Understanding joint movement helps diagnose
osteoarthritis, ligament injuries, and joint instability.clinicsearchonline
 Implant Design: Biomechanics guides the development and testing of prosthetic joints
and fixation devices for durability and functionality.
 Gait Analysis: Detects abnormalities to customize therapy and improve
mobility.clinicsearchonline

Applications in Sports Medicine

 Performance Optimization: Improves athletic techniques by analyzing kinetic and
kinematic factors affecting movement efficiency.
  Injury Prevention: Identifies risk factors and modifies training or equipment use
accordingly.ojs.sin-chn

Applications in Surgical Procedures

 Preoperative Planning: Advanced imaging and computational simulations assist
surgeons in precise surgical approaches and implant placements.
 Surgical Devices: Biomechanics supports the design of surgical tools and robotic
technologies that enhance accuracy and reduce recovery times.clinicsearchonline

Future and Advanced Areas

 Integration of wearable sensors and real-time biomechanical feedback in rehabilitation.
 Computational modeling to predict treatment outcomes.
 Robotics-assisted therapy for improved patient-specific intervention.

Summary
Biomechanics informs every stage of physiotherapy care, from injury assessment and
personalized rehabilitation to surgical planning and sports performance enhancement. By
incorporating biomechanical principles and advanced technologies, physiotherapists can deliver
efficient, evidence-based care that restores function and enhances quality of
life.pubmed.ncbi.nlm.nih+2

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Chapter 7 will explore measurement tools and techniques used to assess biomechanical function
in clinical physiotherapy.

Practice Questions:

1. How does biomechanics improve rehabilitation outcomes?

2. What biomechanical tools are commonly used in physiotherapy clinics?
3. Describe the role of biomechanics in orthopedic implant design.
Glossary:

 Electromyography (EMG)
 Motion analysis
 Gait analysis
 Prosthetic
 Rehabilitation
 Computational modeling

Chapter 7: Biomechanical Measurement Tools and Techniques in Physiotherapy

Overview
Biomechanical assessment tools are essential in physiotherapy to evaluate movement quality,
diagnose dysfunctions, and guide rehabilitation strategies. These tools provide objective data on
joint motion, muscle activity, force application, and gait patterns, improving precision and
treatment effectiveness.physio+2

Common Biomechanical Assessment Tools

Motion Capture Systems
 Use cameras and markers placed on the body to record 3D movement.
 Analyze joint angles, velocity, acceleration of body segments.
 Useful for gait analysis, sports performance, and movement dysfunction assessments.vaia

Force Plates
 Measure ground reaction forces during standing, walking, or jumping.
 Provide data on balance, weight distribution, and impact forces.
 Assist in assessing limb loading asymmetries and postural control.physio+1

Electromyography (EMG)
 Records electrical activity of muscles during contraction.
 Helps understand muscle timing, intensity, and coordination.
 Used to evaluate neuromuscular function and rehabilitation progress.vaia

Inertial Measurement Units (IMUs)

 Wearable sensors that track acceleration and orientation in real-time.
  Portable alternative to lab-based motion capture.
 Useful in continuous monitoring during daily activities or sports.vaia

Clinical Techniques of Assessment

 Visual Observation: First step to identify gross movement abnormalities or
compensations.
 Goniometry: Measures joint range of motion precisely.
 Muscle Strength Testing: Manual or instrumented evaluation of muscle force.
 Postural Analysis: Using plumb lines, digital photography, or force
plates.northshorephysio
 Gait Analysis: Combines video and force data to assess walking patterns.

Data Integration and Software

 Specialized software integrates data from motion capture, force plates, and EMG to
provide comprehensive reports.
 Enables visualization of joint moments, muscle activation, and movement symmetry.
 Facilitates communication with patients and tailoring of rehab programs.

Summary
Effective use of biomechanical assessment tools allows physiotherapists to diagnose impairments
accurately and monitor treatment outcomes objectively. Advances in technology have made
these tools increasingly accessible both in clinics and field settings, enhancing patient
care.northshorephysio+2

Next Chapter Preview:

Chapter 8 will explore muscle mechanics, types of contractions, and their role in producing
movement.

Practice Questions:

1. Name three biomechanical assessment tools and their primary use.

2. How does electromyography aid in muscle function analysis?
 3. Describe the role of force plates in postural assessment.

Glossary:

 Motion capture system

 Force plate
 Electromyography (EMG)
 Inertial Measurement Unit (IMU)
 Goniometry
 Gait analysis

Chapter 8: Muscle Mechanics in Biomechanics and Physiotherapy

Overview
Muscle mechanics is a key component of biomechanics that explains how muscles generate force
and produce movement. Understanding different types of muscle contractions and their
mechanical behavior is essential for physiotherapists to design effective rehabilitation
programs.slideshare+1

Muscle Structure and Function

 Muscles are composed of fibers containing contractile proteins (myosin and actin) that
slide to produce contraction.
 Motor units: one motor neuron and the muscle fibers it controls.
 Muscles generate force to move or stabilize bones across joints.

Types of Muscle Contractions

Isometric Contraction
 Muscle generates force without changing length.
 Important for maintaining posture and joint stability.

Isotonic Contraction
 Muscle changes length producing movement.
 Two types:
 o Concentric: Muscle shortens while generating force (e.g., lifting a weight).
o Eccentric: Muscle lengthens while controlling movement (e.g., lowering a
weight).

Isokinetic Contraction
 Muscle contracts at a constant speed, often using specialized equipment.
 Used for strength assessments and rehabilitation.

Force-Length and Force-Velocity Relationships

 Force-Length: Muscle’s ability to generate force depends on its length; optimal overlap
of actin and myosin increases force.
 Force-Velocity: The speed of contraction inversely affects the force a muscle can
generate; slower contractions produce higher force.

Muscle Mechanics Role in Movement

 Muscles control movement by exerting forces on bones through tendons.
 Muscle coordination and timing are crucial for effective and efficient motion.
 Understanding these mechanics helps in diagnosing muscle dysfunction and planning
therapy.

Clinical Implications
 Assessment of muscle strength and endurance guides rehabilitation.
 Targeting specific types of contractions can aid recovery (e.g., eccentric exercises for
tendon rehab).
 Muscle fatigue and imbalance contribute to injury risk and should be addressed.

Diagrams and Illustrations

 Muscle fiber anatomy and sliding filament theory.
 Graphs depicting force-length and force-velocity curves.
 Examples of concentric, eccentric, and isometric contractions in daily activities.
Summary
Muscle mechanics underpin all human movement. By understanding contraction types and force
relationships, physiotherapists can devise precise and effective intervention strategies to restore
function and prevent injury.cpur+1

Next Chapter Preview:

Chapter 9 will discuss joint mechanics and their role in supporting muscle action and movement.

Practice Questions:

1. Describe the difference between concentric and eccentric muscle contractions.

2. What is the significance of the force-length relationship in muscle function?
3. Why are isometric contractions important in physiotherapy?

Glossary:

 Isometric contraction
 Concentric contraction
 Eccentric contraction
 Force-length relationship
 Force-velocity relationship
 Motor unit

Chapter 9: Joint Mechanics and Movement Biomechanics

Overview
This chapter focuses on the biomechanics of joints which are crucial for movement and stability
in the human body. Joints connect bones and allow various types of movement while
maintaining structural support. Understanding joint mechanics is essential in physiotherapy for
diagnosis, treatment, and rehabilitation of musculoskeletal conditions.slideshare+1

Classification of Joints
  Functional Classification:
o Immovable (Synarthroses)
o Slightly movable (Amphiarthroses)
o Freely movable (Diarthroses or synovial joints).pressbooks.bccampus+1
 Structural Classification:
o Fibrous joints
o Cartilaginous joints
o Synovial joints (most common and mobile type)

Types of Joint Movement

 Rotational (Angular) Movements: Body part rotates around a central point or axis.
 Translational Movements: Bone slides linearly over another without rotation.
 Combination Movements: Most joint motions combine rotation and translation
(curvilinear motion).wikimsk

Osteokinematics vs Arthrokinematics
 Osteokinematics: Observable movement of bones relative to the 3 anatomical planes
(sagittal, frontal, transverse), involving flexion, extension, abduction, adduction, rotation,
and circumduction.
 Arthrokinematics: Small, subtle movements between joint surfaces essential for smooth
motion—includes roll, glide (slide), and spin.wikimsk

Joint Stability and Mobility

 Stability: Maintained by ligaments, joint capsule, muscles, and tendons to prevent
dislocation.
 Mobility: Depends on joint shape, soft tissue flexibility, and neuromuscular control.
 There's a trade-off between stability and mobility in joint design.

The Concave-Convex Rule

 This biomechanical rule describes how joint surfaces move relative to each other during
normal physiological movement:
 o When a concave surface moves on a fixed convex surface, the glide occurs in the
same direction as the bone movement.
o When a convex surface moves on a fixed concave surface, the glide occurs in the
opposite direction to the bone movement.
 Importance: Understanding this rule guides manual therapy techniques aimed at restoring
joint mobility.wikimsk

Motion in Joints
 Joints allow up to six degrees of freedom: three translational and three rotational
movements.
 Joint motion involves forces producing torque and movement controlled by muscles and
ligaments.
 Improper joint mechanics lead to injuries, pain, and dysfunction.

Clinical Relevance
 Joint mechanics knowledge assists physiotherapists in diagnosing joint pathologies.
 Guides rehabilitation strategies focusing on restoring normal joint motion and stability.
 Helps design therapeutic exercises and manual therapy interventions.

Diagrams Suggested
 Joint types with structure illustrations.
 Diagrams showing osteokinematic and arthrokinematic movements.
 Concave-convex rule depicted with joint movement examples (e.g., shoulder and knee).
 Degrees of freedom illustration.

Summary
Joints are complex mechanical structures fundamental to human movement. Biomechanics of
joints highlights how bones, ligaments, and muscles interact to produce stable yet flexible
motion. Mastery of these concepts is vital for clinical assessment and effective physiotherapy
treatment.slideshare+1