Types of Joints• Joint are classified by their range of motion• Threes classes of joints – Immovable – fibrous (collagen connects 2 bones) – Slightly movable – cartilaginous (cartilage connects 2 bones) – Freely moveable - synovial• The freely moveable joints are the ones that are most important for the teaching and practice of yoga
Synovial Joints• The two surfaces of the bones interacting are covered with a thin layer of hyaline cartilage.• Separated by a joint cavity.• A synovial membrane seals the joint cavity and secretes synovial fluid.• The hyaline cartilage and the synovial fluid allows the bone surfaces to slide over each other without friction.• Outside of the joint is tough fibrous joint capsule
Meniscus• Fibrocartilaginous disc• Found within the cavity of the synovial joint, between the two bones• Act to make the two ends of the bones more congruent.• Act as shock absorbers
Synovial Fluid• Allows us to move smoothly• Serves as a lubricant• Serves as a shock absorber• Serves as a source of nutrients for the joint cartilage• Major components are – Glycosaminoglycan – Hyaluronic acid (HA)
Hyaluronic Acid• A tissue lubricant that prevents inflammation and wear of the joint and conserves synovial fluid.• During joint usage or prolonged immoblization HA is lost (this happens when you sleep overnight)• Morning stiffness is related to the lose of HA. As we begin to move HA is secreted which replaces the amount lost during immobilization• Movement therapy stimulates secretion of HA and those makes it an effective treatment for patients with oseoarthritis
Movement Direction• Synovial joints move in one plane (uniaxial), two planes (biaxial), or multiple planes (multiaxial)• Pivot, Hings and Gliding joints are uniaxial• Condyloid and Saddle are biaxial• Ball and socket are multiaxial
Hinge Joint• Allows movement in only one plane/direction• Limited range of motion• Simplest type of joint• While the movement is limited to mainly flexion and extension, there is some slight rotation.• The integrity of the joint is maintained by a strong network of ligaments which ensures stability.
KNEE JOINT• Largest and most complex joint in the body. It is not a simple hinge joint• Three bones articulate to form the joint – Femur, tibia, and fibula• Fundamental movements are flexion and extension.• Hyperextension is possible, but is limited by the anterior cruciate ligament.• When the knee is flexed the structures that provide stability are relaxed, which allows for rotation at the joint
Knee Structure• The meniscus• Provides cushioning• Has no blood supply• Has limited nerve supply
Knee Structure• Joint integrity/stability is maintained by the knee ligaments. – Medial collateral ligament – Lateral collateral ligament – Anterior cruciate ligament – Posterior cruciate ligament• These ligaments act as the primary stabilizers of the joint and guide the movement of the bones in proper relation to one another
The Knee in Yoga• The knee is certainly a major participant in the yoga standing postures• Proper alignment of the postures is essential for preventing misalignment joint stress to the surrounding structures of the joint capsule• One of the most common joint injures in sport activities.
Knee Injuries• Ligament strains – 1st degree – stretching of the ligament fibers – 2nd degree – stretching with some tearing of the fibers – 3rd degree – full tear of the ligament• Cartilage damage (most often it is the medial meniscus)• Bursitis – inflammation of the bursa sacks within the joint capsule• Osteoarthritis (degenerative joint disease)– a wearing away of the cushion between the bones
Patellofemoral Joint• The patella is largest sesamoid (imbedded in the tendon) bone• Contains the largest layers of cartilage in the body• The patella improves the efficiency during the final straitening of the knee, because it holds the quadriceps tendon in alignment.• Decreases friction of the quadriceps tendon• Enhances our ability to flex and extend the knee• Protects the knee joint• Decrease mechanical stress of the joint
PatelloFemoral Joint cont.• Patella/femoral joint is very complex joint• Forces in this joint are a function of the quadriceps force and the angle of knee flexion• Because it is poorly nourished and poorly protected it is susceptible to injury, particularly overuse injuries• Sporting activities can create forces on this joint up to 20x one’s body weight• The joint is very susceptible to degenerative joint disease
Iliotibial Band Syndrome• A common injury that is manifested by pain on the outside of the knee.• The ITB is a tendinous extension of the fascia covering two muscles the gluteus maximus and the tensor fascia lataeAn overuse injury caused by repetitive flexing and extending the knee.
Ankle MusclesBecause the bulk of themuscles involved inankle joint movementare located above thedifferentjoints, rehabilitation ofankle injuries isprolongedAnkle stability is integralto normal motion andminimizing risk of anklesprain
Common Ankle InjuriesInversionSprains – mostcommon of the ankle injuries
Common Foot Problems• Most foot problems are related to the shoes we wear• 80% of foot problems occur in women• Finding the write foot wear – choosing comfort and function over style and status• Important tips for good foot care – shoes made of leather or canvas are good, but sandals are the best, use a foot powder, wash daily.
Common Foot ProblemsPoor Foot Wear Plantar Fasciitis
The Ankle and Yoga• Standing poses build awareness of the feet.• Work on developing range of motion in the toes.• Range of motion exercise for the ankles• Toes raises
Arm Balances• The ankle joint is much more suited for supporting the body because with gravity and our upright posture the ankle becomes stronger as we begin to walk and perform our activities of daily living.• The wrist is not as suited for supporting the body because placing the weight of our body on the wrist is not the norm.• How do we perform arm poses proficiently?