HES 234 Exam 2 Review PDF

**HES 234 Review for Exam \#2** **Joints/articulations/arthroses** Mobility vs. stability **3 types of joints based on functional classification** Synarthroses - immovable Amphiarthroses -- Slightly movable Diarthroses -- highly/freely movable **Types of Synarthroses** Suture -- b/w skull bo...

**HES 234 Review for Exam \#2** **Joints/articulations/arthroses** Mobility vs. stability **3 types of joints based on functional classification** Synarthroses - immovable Amphiarthroses -- Slightly movable Diarthroses -- highly/freely movable **Types of Synarthroses** Suture -- b/w skull bones Gomphosis -- teeth in socket (periodontal ligament) Synchondrosis -- hyaline cartilage separates bones (epiphyseal plates, xyphoid process and body of sternum, 1^st^ costosternal joint) Synostosis -- previous joint that has been fused by bone (frontal suture, closed epiphyseal plate) **Types of Amphiarthroses** Syndesmosis -- large space between bones with little movement possible (interosseous ligament) (distal tibofibular joint) Symphysis -- bones separated by pad of fibrous cartilage (pubic symphysis and intervertebral joints where intervertebral discs form joints between vertebral bodies) **Types of Diarthroses (Synovial joints)** -- most common joint, joint cavity separates bones, hyaline cartilage covers joint surfaces, synovial membrane produces synovial fluid. Accessory structures: fat pads, cartilages (menisci), ligaments, tendons, bursae **Gliding (Plane) joints** -- no angulation [Acromioclavicular, Claviculosternal], [intercarpal, intertarsal joints, vertebrocostal joints], [sacroiliac joints]**.,** [vertebral facet joints] **Hinge joints** monaxial movement [Elbow, knee], [ankle, interphalangeal] **Pivot joints --** Rotation only [Atlas/Axis, Proximal radioulnar joint] **Ellipsoid joints --** biaxial [Radiocarpal joint], [metacarpophalangeal joints (2-5), metatarsophalangeal joints] **Saddle joints --** biaxial [First carpometacarpal joint] **Ball and Socket joints --** triaxial [Shoulder and hip joints] **Types of motion** Linear motion (gliding) Angular motion Rotation **Axes/planes of angular motion** Monaxial Biaxial Triaxial Flexion/Extension, Abduction/Adduction, Opposition, Inversion/Eversion, Protraction/Retraction, Elevation/Depression, Cicumduction, Rotation (C1/C2, Supination/Pronation) **Injuries** Sprain - ligament Strain -- tendon/muscle Dislocation Complete (luxation) Articulating surfaces forced out of position Partial (subluxation) **Spinal Joints** 3 joint complex 2 facet joints (gliding diarthroses) Symphysis joint b/w vertebral bodies C1/C2 exception -- no disc (pivot joint) **Spinal ligaments** Anterior longitudinal ligament Posterior longitudinal ligament Ligamentum flavum (yellow ligament) **Intervertebral discs** Annulus fibrosus and nucleus pulposus IVD herniations **Whiplash** Sprain/Strain injury to the neck **The pectoral girdle** -2 clavicles \- 2 Scapulae Acromioclavicular joint -- gliding diarthrosis Sternoclavicular joint -- gliding diarthrosis AC joint separation -- disruption of ac joint and surrounding ligaments **The glenohumeral joint** (shoulder joint) -- ball and socket joint Supported by glenoid labrum, rotator cuff muscles, numerous other ligaments and muscles Rotator cuff muscles -- Supraspinatus\*\*, Infraspinatus, Subscapularis, Teres minor Injury -- labrum tear **The elbow joint** -- hinge joint diarthrosis Humeroulnar joint -- trochlea of humerus and trochlear notch of ulna Humeroradial joint -- capitulum of humerus and head of radius Supporting muscles -- Biceps brachii -- flexes and Triceps Brachii -- extends Ligaments -- Annular (radial head in radial notch), Ulnal collateral lig., radial collateral lig. **Elbow Injuries** Medial epicondylitis =golfer's elbow/damage to ulnar collateral ligament = pitcher's elbow Lateral epicondylitis = tennis elbow **The wrist -- mostly gliding joints** **The pelvic girdle** Pelvis bones -- ilium, ischium, pubis = innominate Sacrum Coccyx **The hip joint** -- ball and socket diarthrosis Stable Head of femur in acetabulum of innominate Labrum and ligament of femoral head increases stability Many surrounding ligaments and muscles **Injuries** -- Dislocations, Sprains, Strains, Labrum tears, Fractures of femoral neck **The knee joint**- hinge diarthrosis Femur-Tibia articulations -- Lateral and medial condyles Patella- Femur articulation Ligaments Anterior and posterior cruciate ligaments Medial and lateral collateral ligaments Menisci Medial and lateral menisci -- give knee lateral stability Other structures Fat pads, bursae Injuries ACL, MCL/LCL, meniscus, Unhappy triad (ACL, MCL, meniscus) "Plant and twist" **The ankle joint** -- Hinge diarthrosis (talus and tibia articulation) Lateral ligament [-- most commonly sprained] **-- Anterior talofibular ligament**, then calcaneofibular, and posterior talofibular Medial ligament -- Deltoid ligament **Arthritis** Osteoarthritis -- most common -- joint degeneration Rheumatoid arthritis -- autoimmune -- inflammation of synovial membrane -- joint destruction Gouty arthritis (Gout) -- Uric acid deposition **Arthroscopy** -- procedure to look inside and repair a joint **Arthroplasty** -- surgical replacement of a joint **Muscles Physiology/Histology** 3 types of muscle -- skeletal (striated) (voluntary), cardiac (striated) (involuntary), Smooth (nonstriated) (involuntary) **Muscle connective tissue** -- Dense regular CT proper -- become tendon at ends of muscle Epimysium-surrounds outside of muscle Perimysium -- surrounds fascicles Endomysium -- surrounds fibers **Muscle -- fascicles -- fibers (cells) -- myofibrils (multiple sarcomeres) -- myofilaments (actin and myosin)** Skeletal muscle fibers -- Very long cells/hundreds of nuclei/ made through fusion of myoblasts in utero **Muscle terminology:** Cell= fiber Cytoplasm= sarcoplasm Plasma membrane= sarcolemma Ca++ storage organelle= sarcoplasmic reticulum **Sarcomere** -- smallest/basic functional unit of skeletal muscle Made up of 2 Z-discs and the actin and myosin filaments between them. Multiple sarcomeres connected end to end = myofilament Sarcolemma resting potential = -90mV (don't have to know the numbers) Sarcolemma action potential threshold = -55mV **Steps in muscle contraction (excitation-contraction)** 1\. Action potential is generated in the central nervous system and travels down motor neuron to neuromuscular junction. 2\. Neuron releases Acetylcholine (ACh) at the NMJ. 3\. ACh diffuses across space between the neuron and the muscle motor end plate (synaptic cleft) 4\. Ach binds to Ach receptor proteins on the surface of the sarcolemma at the motor end plate and is then quicky broken down by acetylcholinesterase. 5\. This binding of Ach to its receptors triggers Na+ channels to open. 6\. Na+ rushes in and depolarizes the sarcolemma from -90mV to -55mV (don't have to know the numbers) 7\. An action potential in the muscle fiber is triggered. 8\. The action potential of the muscle fiber spreads quickly across the surface of the cell like a wave causing Na+ channels to open for a brief period of time. 9\. As the wave of depolarization passes an area of the sarcolemma, Na+ channels close and repolarization of the sarcolemma and a return to resting potential occurs. 10\. The wave of depolarization spreads into the t-tubules, which are situated next to sarcoplasmic reticuli. 11\. The depolarization of the sarcolemma next to the sarcoplasmic reticuli causes them to release Ca++ into the sarcoplasm. 12\. Ca++ bind to troponin and the troponin/tropomyosin complex moves off of the actin active sites. 13\. Myosin heads bind to the active sites (cross-bridging) and then undergo a powerstoke. 14\. Upon completion of a powerstroke, each myosin head releases an ADP and Phosphate molecule 15\. An ATP molecule then binds to a myosin head which causes the myosin head to detach from the actin filament. 16\. After detachment, the ATPase enzyme splits the ATP molecule into ADP and a phosphate molecule and the energy released is used to "reposition" the myosin head. \*\*Powerstrokes and "reposition" of myosin heads continue as long as there continues to be Ach release and action potentials in the muscle fiber and Ca++ and ATP present in the sarcoplasm. \*\*As powerstokes occur, actin and myosin filaments slide past one another, shortening the distance between Z-discs (shortening sarcomeres). This causes a pull on the connective tissues and a tension production in the tendons of the muscle. **Relaxation of muscle fiber** 1\. If action potentials end, Ca++ is quickly taken back up by sarcoplasmic reticuli. 2\. Ca++ no longer is bound to troponin and this causes the troponin/tropomyosin complex to once again cover the actin active sites. 3\. No more cross-bridging can occur. 4\. Fiber returns to resting length through: Elastic recoil, gravity and opposing muscle action (antagonist action) **ATP production:** Muscle cells store enough ATP for a second of contraction, then it must be made. ATP can be recycled with the use of creatine phosphate ADP + creatine phosphate = ATP + creatine (enzyme used is creatine phosphokinase) ATP + creatine = creatine phosphate + ADP This process can last about 15 seconds **Anaerobic Glycolysis** Production of ATP from glucose without the use of oxygen Produces enough ATP to keep muscle functioning a little while longer Causes build up of lactic acid **Aerobic metabolism** Production of ATP from glucose, fat or protein with the use of oxygen. Uses the Kreb's Cycle to produce a lot of ATP Can sustain muscle fiber contraction for long periods of time **Slow twitch and fast twitch muscle fibers** Red meat vs. white meat (myoglobin and blood supply) **ST fibers** -- High aerobic capacity, slow to contract, less powerful than Ft fibers, small motor units **Fta fibers** -- (intermediate fibers), medium aerobic capacity, high anaerobic capacity, fast contraction speed **Ftb fibers** -- Low aerobic capacity, high anaerobic capacity, fast contraction speed, large motor units **Muscle hypertrophy**- We can increase the size of our muscles by working out The increase in size is an increase in fiber size, not an increase in fiber numbers. More actin and myosin filaments are added to the fibers to make them larger. **Muscle atrophy --** Due to lack of use Loss of muscle mass due to a reduction in the number of actin and myosin filaments in our fibers **Motor unit =** motor neuron and the muscle fibers it innervates Small motor units = fine motor control Large motor units = strength **Length-Tension relationship skeletal muscles** If a muscle and its fibers and sarcomeres are overly shortened at the beginning of contraction, less force(tension) can be produced. If a muscle and its fibers and sarcomeres are overly stretch at the beginning of contraction, less force (tension) can be produced. If a muscle and its fibers and sarcomeres are just the right length with some overlap of actin and myosin, but not too much overlap, then the maximal amount of tension can be produced. "the Goldylocks zone" 3 Phases of a muscle fiber twitch Latent phase Contraction phase Relaxation phase Stimulus frequency and tension production \*Higher stimulus frequency=more tension production Subsequent stimuli arrive right at the end of the relaxation phase = **Treppe** Subsequent stimuli arrive before end of relaxation phase = **Wave summation** Wave summation tops out as **incomplete tetanus**. Subsequent stimuli arriving very close together = **Complete tetanus** \*\*\*Normal muscle contraction involves Complete tetanus of multiple muscle fibers in a muscle\*\*\* **Parts of a muscle** Origin -- fixed end Belly -- where all the fibers are (middle) Insertion -- movable end Skeletal muscle shapes Parallel Convergent Circular Pennate -- Unipennate, Bipennate, multipennate Bipennate produces more tension because there are more muscle fibers/unit area **Muscles and their actions** Agonist (prime-mover) does the action (biceps brachii -- flexes elbow) Synergist -- helps the prime mover do the action (brachialis) Antagonist -- muscle that opposes the action and must relax for action to occur (triceps brachii) Fixator(s) -- prevents movement at another joint (Rotator cuff, deltoid, rhomboids) **Types of muscle contraction** Isometric -- tension production without a change in length Isotonic -- tension production with a change in length Concentric -- shortening of the muscle Eccentric -- lengthening of the muscle **Intrinsic vs. Extrinsic muscles** **Common flexor and extensor origin for wrist and hand muscles** **Anterior muscles acting on the hip** Iliopsoas -- primary hip flexor **Lateral thigh muscles** Tensor Fasciae Latae Iliotibial band Gerdy's tubercle **Flexors of the knee** Hamstring muscles Biceps femoris Semitendinosis Semimembranosis **Extensors of the knee** Quadriceps muscles Rectus femoris Vastus lateralis Vastus medialis Vastus intemedius **Sartorius** -- "tailors muscle" Crosses leg **Gracilis** -- Adductor muscle of hip **Pes Anserine** Insertion of Sartorius, Gracilis and Semitendinosis Pes anserine bursitis **Compartments of the leg** Anterior Lateral Deep posterior \*Superficial posterior Gastrocnemius -- plantar flexion Soleus -- plantar flexion Common tendon = calcaneal tendon