The Articular System PDF

The Articular System  Joints (“Arthrosis”) Articulations of bones (points of contact between two bones). Functions of joints: ○ Hold bones together ○ Allow for mobility (flexibility and movement) Ways joints are classified: ○ Functionally (type & extent of movement) ○ Structurally...

The Articular System  Joints (“Arthrosis”) Articulations of bones (points of contact between two bones). Functions of joints: ○ Hold bones together ○ Allow for mobility (flexibility and movement) Ways joints are classified: ○ Functionally (type & extent of movement) ○ Structurally (what they are made of)  Functional Classification of Joints Joints can be classified Synarthrosis based on the range of ○ Generally immovable motion the joint permits ○ E.g. skull Amphiarthrosis ○ Immovable or slightly moveable ○ E.g. vertebrae Diarthrosis ○ Freely moveable ○ E.g. hip joint  Structural Classification of Joints Fibrous joints ○ Generally immovable ○ E.g. skull Cartilaginous joints ○ Immovable or slightly moveable ○ E.g. vertebrae Synovial joints ○ Freely moveable ○ E.g. hip joint  Fibrous Joints Bones united by fibrous connective tissue – “synarthrosis” (largely immovable). E.g. Suture joints of the skull. Cartilaginous Joints – Mostly “amphiarthrosis” (slightly moveable). Bones connected by cartilage. Examples: Intervertebral “discs” joints Symphysis pubis F Synovial Joints - “Diarthrosis” (freely moveable joint). Articulating bones are separated by a joint cavity containing synovial (lubricating) fluid is found in the joint cavity. Also contain cartilage and joined by ligaments (elastic tissue). 6 Characteristics of Synovial Joints Articular cartilage (hyaline cartilage): protects the ends of bones, smooth and a shock absorber. Articular (Joint) capsule: synovial membrane (semi-permeable) and fibrous capsule (prevents fluid leakage). Joint cavity: filled with synovial fluid (reduces friction and provides nutrients). 6 Characteristics of Synovial Joints Bursae: (singular “bursa”): small, flat fluid sacs, reduce friction between bones and ligaments and tendons. Intrinsic ligaments: thick bands, reinforce the joint capsule. E.g. A.C.L. (anterior cruciate ligament) Extrinsic ligaments: outside the capsule, reinforce joint, attach bone to bone. E.g. Patellar ligament.  The Synovial Joint: E.g. Shoulder Joint Articular cartilage, joint capsule, joint cavity, bursae, ligaments (intrinsic/extrinsic)  6 Types of Synovial Joints: ❏ GLIDING (E.g. between the carpals and tarsals) ❏ HINGE (E.g. elbow joint and between phalanges) ❏ PIVOT (E.g. joint between C1-C2) ❏ ELLIPSOID (E.g. wrist joint) ❏ SADDLE (E.g. thumb joint) ❏ BALL-AND-SOCKET (E.g. hip and shoulder joints)  6 Types of Synovial Joints: Details... 1. GLIDING joints: -Connects flat or slightly curved bones. -E.g. between the carpals and tarsals 2. HINGE joints: -Convex portion fits into concave portion. -Movement in one plane. -E.g. elbow joint and between phalanges 3. PIVOT joints: -Rotation in one plane (uni-axial). -Rounded point of one bone into groove of another. E.g. joint between C1-C2)  6 Types of Synovial Joints: 4. ELLIPSOID joints: -Movement in 2 planes. -E.g. wrist joint 5. SADDLE joints: -Movement in 2 planes (i.e. flexion-extension, abduction-adduction) E.g. thumb joint 6. BALL-AND-SOCKET joints: -Movement around 3 axes. E.g. hip and shoulder joints  Common Sport Injury Terms: TISSUE PROPERTIES: -Each tissue has a tolerance/breakpoint. -Depending on its stretch threshold it will tear, sprain or pull. LIGAMENTS: -Tissues that attaches bone to bone. -Tough bands of white, fibrous tissues. -Allow a minimal amount of stretch (but less than tendons), usually will tear (sprains). - “Static” stabilizers of joints. -Ligaments and cartilage are avascular (their nutritional needs are NOT met through blood but rather through diffusion).  Common Sport Injury Terms: TENDONS: -Attach muscle to bone. -Large bundles of white, fibrous protein (collagen). -Greater stretch than ligaments. -Will tear (strain) with great enough force.  Common Sport Injury Terms: “Sprains” to ligaments. “Strains” to muscles/tendons (helps to remember we train muscles). 3 Categories of severity (grades): 1st Degree: mild, short healing time (few days). 2nd Degree: moderate, diagnosis and treatment. 3rd Degree: severe, may require surgery/rehabilitation.  Common Sport Injury Terms: TENDINITIS: -Inflammation (“-itis”) of a tendon. -Caused by irritation due to abnormal or prolonged use. -Treatment: rest, cold/heat therapy, possible cast/splint, anti-inflammatories. -E.g. Biceps tendinitis BURSITIS: inflammation of the bursa. ARTHRITIS: inflammation of the joint.  Common Sport Injury Terms: DISLOCATIONS: -When a bone is displaced from its original location. E.g. Shoulder dislocation “pops out” -Usually damage to the joint capsule and ligaments. -Muscles/tendons may also tear. SYMPTOMS: (seek medical help) -Joint is deformed. -Joint is painful when palpated or moved. -Joint is not functional.  Common Sport Injury Terms: SEPARATIONS: -Ligament tears which separate bones from each other. E.g. Acromioclavicular (shoulder) separation (lateral end of the clavicle). E.g. Sternoclavicular separation (medial end of the clavicle).  Common Sport Injury Terms: 3 Types of Cartilage: 1. Hyaline Cartilage: most common. At ends of bones and free-moving joints. 2. Fibrocartilage: very strong. Between vertebrae. 3. Elastic cartilage: “yellow” cartilage. E.g. External ear, auditory tube, epiglottis. -Cartilage is avascular (no blood supply, therefore long healing time. -Arthroscopy: surgical procedure to diagnose/treat “torn” cartilage.  Common Sport Injury Terms: SHIN SPLINTS: -The tearing of the interosseous membrane (between the tibia and fibula) or the periosteum (lining of the bone). -Painful overuse condition, occurs on the shaft of the tibia (often medial or lateral side). -Risk factors: training surface or gear (e.g. uneven/hard surfaces, old shoes), changes to training (e.g. frequency, duration, intensity). Sport Injury Treatments: S.H.A.R.P. Tips for treating signs of S.H.A.R.P.: -Apply pressure and ice at the same time. Ice 10-20 minutes on and off (cover skin with paper towel). -Elevate during icing to reduce future swelling. -Restrict/rest injured area (may use sling/tensor). -Seek medical diagnosis. -Training prevention: train muscles evenly to minimize imbalance, 1:1 ratio, agonist:antagonist (e.g. train quadriceps:train hamstrings).  Sport Injury Treatments: P.I.E.R. Tips for treatment: -Apply pressure and ice at the same time. Ice 10-20 minutes on and off (cover skin with paper towel). -Elevate during icing to reduce future swelling. -Restrict/rest injured area (may use sling/tensor). -Seek medical diagnosis. -Training prevention: train muscles evenly to minimize imbalance, 1:1 ratio, agonist:antagonist (e.g. train quadriceps:train hamstrings).  Common Sport Injury Terms: Rotator Cuff tear: -May include 1 or 4 of the rotator cuff muscles. -Supraspinatus -Infraspinatus -Teres Minor -Subscapularis  Common Sport Injury Terms: KNEE JOINT Anatomy: -Classified as a ‘modified’ ellipsoid joint (flexion, extension, slight rotation) -Femur: distal end articulating cartilage. -Tibia: proximal end has 2 menisci (sing. meniscus). Thick fibrocartilage discs which sit on the tibial condyles. -2 Cruciate ligaments: interior ligaments that ‘cross’ and stop anterior/posterior movements of the knee joint. -A.C.L.: Anterior Cruciate Ligament -P.C.L.: Posterior Cruciate Ligament  Common Sport Injury Terms: KNEE JOINT Anatomy cont’d: -Exterior knee ligaments provide knee joint with medial/lateral stability. -M.C.L.: MEDIAL COLLATERAL (Tibial) LIGAMENT -L.C.L: LATERAL COLLATERAL (Fibular) LIGAMENT  Common Sport Injury Terms: KNEE LIGAMENT TEARS: -Often ‘blows’ to the lateral side of the knee. -Damage results to the medial side. -Tears can occur to the joint capsule, M.C.L., medial meniscus and/or A.C.L. -Athletes with greater than 20% “Q” ANGLE (Quadriceps angle) are at greater risk. Common Sport Injury Terms: Q Angle (“Quadriceps Angle”) -around 14 degrees for males and 17 degrees for females -affects the overall alignment of patella -can cause pain around the patella; linked to ACL injuries  Common Sport Injury Terms: OSGOOD-SCHLATTER SYNDROME: -Affects the epiphyseal (growth) plate of the tibial. -Experienced as ‘growing pains’ if the tibial tuberosity is overused/overloaded. -Treatment: Medical diagnosis, P.I.E.R. principle.  Common Sport Injury Terms: PATELLOFEMORAL SYNDROME (PFS): -Gradual onset of anterior knee pain. -Aggravated by certain sports. -Pain may result from increased or misdirected forces between the patella and the femur.  Common Sport Injury Terms: ANKLE JOINT ANATOMY: - ‘Modified’ hinge joint. - Distal ends of tibia (medial malleolus) and fibula (lateral malleolus) rest on the talus. - Joint allows plantar/dorsiflexion and inversion/eversion. - Anterior and Posterior TIBIOFIBULAR Ligaments. - Anterior and Posterior TALOFIBULAR Ligaments. - CALCANEOFIBULAR Ligament. - DELTOID Ligament: strong ligament on the medial side.  Common Sport Injury Terms: INVERSION SPRAINS: - “Twisted ankle” or “Rolling over” during inversion past the normal R.O.M. (range of motion). - Ankle joint is weakest in plantar flexion, during sports with jumping and direction changes. - Injury of one or more of the lateral ligaments of the ankle. - Use the P.I.E.R. principle to manage; elevation to minimize swelling.  Common Sport Injury Terms: EVERSION SPRAINS: -Rare sprains due to the strong deltoid ligament. POTT’S FRACTURE: severe eversion injury, break of the tip of the medial malleolus and a break of the fibula. -Caused by a force on the medial side of the ankle. -Treatment: cast 8-12 weeks and physiotherapy.  VIDEOS: Joint Anatomy  VIDEOS: Joint Injuries