Lecture Notes - Joints of the Upper & Lower Limbs

1. Sternoclavicular - only bony union of upper limb to axial skeleton - multiaxial
   1. Bones - manubrium, clavicle
   2. Cartilages - articular cartilage, articular disc, costal cartilage
   3. Ligaments - capsule
   4. Weakness, etc. - none - clavicle usually breaks before dislocation occurs
2. Acromioclavicular - slightly movable planar
   1. Bones - lateral end of clavicle - articular surface of acromion
   2. Cartilages - articular, articular disc, disc often incomplete
   3. Ligaments -
      • capsular - acromioclavicular
      • accessory - coracoclavicular - actually a syndesmosis
   4. Weakness - "shoulder separation," disruption of acromioclavicular joint and coracoclavicular ligament
3. Shoulder - glenohumeral - scapulohumeral -freely movable, multiaxial - ball and socket
   1. Bones - glenoid fossa of scapula, head of humerus
   2. Cartilages - articular, glenoid labrum
   3. Ligaments -
      • capsular - glenohumeral bands (superior, middle, inferior), coracohumeral
      • accessory - coracoacromial, transverse humeral
      • accessory structures - long head of biceps, subscapular bursa, rotator cuff
   4. Weakness - anterior dislocation most common - inferior often in children, rotator cuff tear - usually the supraspinatus which often deteriorates with age - wear and tear
4. Elbow - humeroulnar & humeroradial (proximal radioulnar is included in capsule ) uniaxial - hinge
   1. Bones - trochlea and capitulum of humerus, head of radius, trochlear notch of ulna
   2. Cartilages - articular
   3. Ligaments - capsular only - ulnar and radial collateral, annular (forms proximal attachment of radial)
   4. Weakness - ulna most commonly dislocated post., epicondylitis, "pitcher's elbow", "pulled elbow"
5. Radioulnar - pivot joint, allows rotation (pronation and supination), about 135 degrees of rotation
   1. Proximal radioulnar
      • bones - head of radius, radial notch of ulna
      • ligaments - annular ligament (lined by cartilage)
   2. Interosseous membrane - a syndesmosis between the interosseous margins of radius and ulna
   3. Distal radioulnar
      • bones - head of ulna, styloid of ulna and ulnar notch of radius
      • ligaments - capsular only, none to name
      • accessory structure - articular disc - acts as a ligament between ulnar styloid and ulnar notch of radius
6. Wrist - complex joint, condyloid, planar, and ball and socket; multiaxial with limited movements
   1. Radiocarpal - "Wrist joint" between radius and ulnar disc proximally and proximal row of carpals distally
      • bones - radius, scaphoid, lunate, triquetrum (carpals act as a unit)
      • cartilages - ulnar disc, articular cartilages of participating bones
      • ligaments - dorsal and palmar radiocarpal, radial and ulnar collateral, and interosseous
   2. Midcarpal - between proximal and distal row of carpals
      • bones - scaphoid, lunate, triquetrum (prox. unit); trapezium, trapezoid, capitate, hamate (dist. unit)
      • cartilages - articular of participating bones
      • ligaments - dorsal and palmar, collateral, and interosseous
   3. Carpo-metacarpal - between distal row of carpals and combined metacarpals 2-5
      • bones - trapezium, trapezoid, capitate, hamate (prox. unit); metacarpals 2-5 (dist. unit)
      • cartilages - articular of participating bones
      • ligaments - dorsal and palmar, collateral, and interosseous
   4. Thumb - trapezial-metacarpal, multiaxial saddle joint
      • bones - trapezium, first metacarpal
      • cartilages - articular of participating bones
      • ligaments - dorsal and palmar, collateral, and interosseous
   5. Piso-triquetral - separate joint, but found at wrist, closely associated with tendon of flexor carpi ulnaris muscle; the pisiform is a sesamoid bone in its tendon; a plane joint with triquetrum
   6. Weaknesses: scaphoid fractures, lunate dislocation is common
7. Intermetacarpal - between metacarpals 2-5 (act as a functional unit) deep transverse metacarpal lig. binds together
8. Metacarpophalangeal (MP joints) - between distal ends of metacarpals and bases of proximal phalanges
9. Interphalangeal (PIP and DIP joints) - between adjacent phalanges of same digit
   Note: Both MP and IP joints are held together by palmar ligaments, and the extensor expansion, the I-P joints have collateral ligaments as well
10. Hip joint: Multiaxial- ball and socket - designed for stability as well as free motion
    1. Osteology:
       1. Hip bone--os coxae - 3 embryological parts - ilium, ischium, pubis; Parts: Acetabulum, acetabular notch, acetabular fossa
       2. Femur: Parts related to joint: Head, neck, fovea capitis, intertrochanteric line and crest
    2. Movements: Adduction-abduction,Extension-flexion, Medial-lateral rotation, Circumduction
    3. Joint components:
       1. Cartilages: articular, acetabular labrum
       2. Synovial membrane
       3. Ligaments:
          1. Capsular: iliofemoral, ischiofemoral, pubofemoral
          2. intracapsular: ligamentum capitis femoris
          3. other: transverse acetabular ligament, zona orbicularis
       4. Bursae: iliopectineal
       5. Vessels:
          1. Medial and lateral circumflex femoral and obturator vessels
    4. Injuries: Arthritic, dislocations, fractures, avascular necrosis
11. Knee joint: Primarily a hinge joint, with gliding and a small amount of rotation; GENU = Knee
    1. Osteology:
       1. Femur: medial and lateral condyles and epicondyles, patellar surface, intercondylar fossa,
       2. Patella: articular surfaces, attachments for quadraceps femoris and patellar lig.
       3. Tibia: med. and lat. condyles, intercondylar eminence, intercondylar tubercles
    2. Movements: Extension, flexion, Medial and lateral rotation
    3. Joint components:
       1. Cartilage: articular; medial and lateral menisci - bear weight in standing position
       2. Synovial membrane, infrapatellar synovial fat pad
       3. Ligaments:
          1. Capsular: medial (tibial) collateral (MCL), patellar, patellar retiniculae
          2. Intracapsular: anterior (ACL) a nd posterior (PCL) cruciate
          3. Extracapsular: fibular collateral (LCL); Note - it is not attached to the capsule or lat. meniscus
          4. Dynamic: muscles crossing joint - intregrity of the joint is highly dependent on muscles
       4. Bursae: Supra and infrapatellar, subcutaneous prepatellar; abnormal - "Baker's cyst"
       5. Muscles: intracapsular portion of popliteus
    4. Injuries: Arthritic, dislocations, sprains, fractures, tears of ligaments and cartilages. "Terrible triad," "Drawer sign" and testing, "3 C's (collaterals, cruciates, and cartilages).
    5. Abnormalities: Genu varus and Genu valgus
12. Tibiofibular joints: Proximal and distal synovial joints and interosseous syndesmosis - little movement.
    1. Osteology: articular surfaces and interosseous crests of tibia and fibula
    2. Cartilages: articular
    3. Ligaments: anterior and posterior tibiofibular capsular ligs., transverse tibiofibular, interosseous mem.
13. Ankle joint: Talocrural Joint: A hinge joint, A mortise and tenon joint by shape
    1. Osteology: Malleoli of tibia and fibula, trochlea of talus
    2. Cartilages: Articular
    3. Ligaments:
       1. Medial: deltoid lig.
       2. Lateral: anterior and posterior talofibular, calcaneofibular
    4. Vessels and nerves: those in area
    5. Injuries: Sprains most common, especially involving lateral ligaments because of freedom of inversion; Pott's fracture: avulsion of distal tibia and fracture of fibula, tearing of associated ligaments
14. Intertarsal joints:
    1. Subtalar joint: note tarsal sinus and interosseous talocalcaneal ligament
    2. Transverse tarsal joint: Primarily responsible for inversion and eversion, allows foot to accomodate irrregular surfaces, although all tarsal and the ankle joints also contribute.
15. Intermetatarsal, metatarsophalangeal, and interphalangeal ligaments
16. Arches of the foot: Transverse and Longitudinal arches supported by plantar aponeurosis, calcaneometatarsal ligament, long and short plantar ligaments, spring ligament