Joints Of Limbs -2015-ruan.ppt

Joints of upper limb I. Joints of shoulder girdle: 1. The acromioclavicular joint 2. The sternoclavicular joint

II. Joints of free upper limb: 1. 2. 3. 4.

The glenohumeral joint (shoulder joint) Elbow Joint Joints between ulna and radius Joints of hand (wrist joint complex)

I. Joints of shoulder girdle: 1. Sternoclavicular joints –

a synovial saddle joint composed of two portions（the sternal end of the clavicle and the manubrium ）separated by an articular disc.

–

allows movement of the clavicle, predominantly in the anteroposterior & vertical planes, although some rotation also occurs.

3. Acromioclavicular joints （ AC joint） – the junction between the acromion and the clavicle.

– allows the ability to raise the arm above the head. – a gliding synovial joint.

II. Joints of free upper limb: 1. Glenohumeral joint (shoulder Joint ) • synovial ball and socket joint

• involves articulation between the glenoid fossa of the scapula and the head of the humerus . • Permits a wide range of movement • shallowness and looseness • deepened by glenoid labrum

• much easier to dislocate than most other joints in the body.

(1) Stabilizers of the Glenohumoral joint The glenohumeral joint is stabilized by ligaments, tendons, cartilage and muscles 1) ligaments :

CHL

Tr

①Glenohumeral ligaments (SGHL, MGHL, IGHL) ②Coracohumeral ligament

(CHL) ③Transverse humeral ligament (Tr, a broad band passing from

the lesser to the greater tubercle of the humerus)

THL

Stabilizers of the Glenohumoral joint 2) Tendon: • biceps tendon (long and short heads) 3)

Glenoid labrum

THL

6

•

Stabilizers of the Glenohumoral joint 4) Muscles (rotator cuff) – The rotator cuff is the group of

muscles and their tendons that act to stabilize the shoulder joint. – Four muscles of the rotator cuff： • Supraspinatus • Infraspinatus

• teres minor • subscapularis

•

Stabilizers of the Glenohumoral joint

• One main purpose of the rotator cuff muscles is pull the humerus into the scapula such that the two bones are fitted tightly against one another.

• Stabilizers of the Glenohumoral joint • The four muscles of the rotator cuff, along with the teres major and the deltoid, make up the six scapulohumeral muscles of the human body

Tendons of Rotator Cuff Muscles

10

5) Ligaments above the shoulder joint ① Coracoclavicular ligament(CCL) ② Coracoacromial ligaments (CAL)

CCL

CAL

(2) Dislocated shoulder • Occurs when the humerus separates from the scapula at the glenohumeral joint.

• The shoulder joint has the greatest range of motion of any joint in the body and as a result is particularly susceptible to dislocation. • Approximately half of major joint dislocations are of the shoulder. • Partial dislocation of the shoulder is referred to as subluxation (半脱拉).

1) Types of shoulder dislocation ①anterior dislocation of the shoulder ( forward, 95%) – sub-coracoid – Sub-glenoid – subclavicular

②posterior dislocation of the shoulder ( backward, 4%) – electrocution – Seizure

Types of shoulder dislocation 3) Inferior dislocation of the shoulder(downward, < 1%)

– Called as subluxation (半脱拉)

2. Elbow Joint • is formed by the humerus , radius and ulna.

• Including ①humeroulnar joint ,②humeroradial joint ③proximal radioulnar joints.

16

2. The Elbow Joint (1) Features of structure: •

Three joints were covered by one joint capsule

•

The joint capsule is thin and loose anteriorly and posteriorly

• The joint capsule is thick and strong on either side strengthened by collateral ligment (ulnar lig. and radial lig.)

• The arm forms an obtuse angle (the carrying angle, 5 to 15 °) with the forearm. 17

(2) Obtuse angle (carrying angle, 5 to 15 °) • The angle formed by the axes of the arm and the axes of forearm when the elbow is fully extended and forearm is supinated. • This angle allows your forearms to clear your hips when you swing your arms, such as during walking. It is also important when carrying objects. • Certain fractures of the elbow can • If the angle is decreased increase the carrying angle of the so that the arm points elbow, causing the arms to stick out toward the body, it is too much from the body. This is called a “gunstock called an excessive carrying angle. deformity(枪托畸形）."

(3) The movement • the simple hinge-joint

• flexion and extension • Proximal radioulnar joint is a pivot , which allows for movements of rotation （pronation and supination).

(4) Ligments of the elbow Joint 1) Ulnar Collateral Ligament(UCL) 2) Radial Collateral Ligament 3) Annular Ligament: stabilizes and encircles the head of the radius

(5) Elbow dislocate

3. Joints between ulna and radius (1) proximal radioulnar joint (pivot-joint ) – between the head of the radius and the radial notch of the ulna and the annular ligament. (2) distal radioulnar joint (pivotjoint ) – between the head of the ulna and the ulnar notch of the distal radius. (3) interosseous membrane of forearm.

4. Joints of hand (wrist joint complex) •

formed between the distal

ends of the radius and ulna and the carpal bones. •

Includes: (1) Wrist joint (2) Joints between carpus

(3) Joints between digits

(1) The wrist joint (radiocarpal joint) – the joint between distal end of

the radius, triangular articular disc and the proximal row of carpus (scaphoid, lunate,

triquetral). – It is a ellipsoid synovial joint .

(2) Joints between carpus –

intercarpal joints

– carpometacarpal joints

(CMC)

– intermetacarpal joints

(3) Joints between digits – Metacarpophalangeal joints (Ellipsoid Joint) – Interphalangeal (Hinge Joint)

joints

Joints of lower limbs I. Joints of pelvic girdle 1. Sacroiliac joints 2. Pubic symphysis

II. Joints of free lower limbs 1. 2. 3. 4.

The hip joint Knee joint Tibiofibular joints Joints of foot

I. Joints of pelvic girdle 1. Sacroiliac joints – Is formed between the auricular surfaces of the sacrum and the two hip bones. – It is amphiarthroses, enclosed by very taut joint capsules. – strengthened by the anterior, and posterior sacroiliac ligaments and iliolumber lig.

2. The pubic symphysis – is the midline cartilaginous joint uniting the left and right pubic bones.

3. Ligaments of pelvic 1) The sacrotuberous ligament – runs from the sacrum to the tuberosity of the ischium. 2)The sacrospinous ligament – Between the ischial spine of the sacrum and coccyx. 3) The obturator membrane • The greater and lesser sciatic foramen – Formed by the sacrotuberous and – is a thin fibrous sheet, sacrospinous ligaments, and which almost greater and lesser sciatic notches. completely closes the obturator foramen.

II. Joints of free lower limbs 1. The hip joint – formed by the femoral head and acetabulum – is a ball and socket joint – the acetabulum is deepened by acetabular labrum. – The joint capsule is tight ,thick and strong – support the weight of the dynamic in both static and dynamic postures. – The range of movement is wide but limited

(1) Strengthened ligaments of the hip joint: 1) intracapsule ligment ①the round ligament of the femur - connect the head of the femur to the acetabulum. ② transverse acetabular ligament - crosses the acetabular notch, which is in reality a portion of the acetabular labrum.

(1) Strengthened ligaments of the hip joint: 2) extracapsular ligaments： • pubofemoral • Iliofemoral • ischiofemoral

2. Knee joint • the largest and most complicated joint in the human body. • consists of two articulations:

(1) tibiofemoral joint (gliding) • between the femur and tibia (2) patellofemoral joint (gliding)

• between the femur and patella. • Flexion and extension

Knee Joint – Sagittal Section

36

Knee Joint • The joint capsule anteriorly consists of patella and extensions of quadriceps femoris tendon

37

• Capsule strengthened by extracapsular and intracapsular ligaments 1) Extracapsular ligaments: – patellar ligament – medial (tibial) collateral ligament (MCL ) – lateral (fibular) collateral ligament (LCL ） – oblique popliteal ligament

oblique popliteal ligament

Extracapsular ligaments of Knee

2) Intracapsular ligaments : • The knee is stabilized by a pair of cruciate ligaments. ①Anterior cruciate ligament (ACL) – from the lateral condyle of femur to the anterior intercondyloid area of the tibia. – prevents the tibia from being pushed too far anterior and medial rotation of the tibia in relation to the femur. – often torn during twisting or bending of the knee.

2) Intracapsular ligaments :

2) Intracapsular ligaments : ②Posterior cruciate ligament (PCL)

– from medial condyle of femur to the posterior intercondylar area of tibia. – prevents the tibia from being pushed too far posterior relative to the femur.

– Common causes of injuries are direct blows to the flexed knee, such as the knee hitting the dashboard in a car accident or falling hard on the knee, both instances displacing the tibia posterior to the femur

2) Intracapsular ligaments : ③Transverse ligament – connects the anterior convex margin of the

lateral meniscus to the anterior end of the medial meniscus.

– Protection of menisci when knee flexion and extension.

3) cartilage of the Knee Joint ①hyaline cartilage covers the surface along which the joints move. ②fibrous cartilage (the meniscus) has tensile strength and can resist pressure. – the medial meniscus （bigger , C-shaped) – the lateral meniscus (smaller, O-shaped) – protect the ends of the bones from rubbing – may be cracked, or torn, – deepen the tibial sockets into when the knee is forcefully which the femur attaches. rotated and/or bent. – play a role in shock absorption.

Knee (meniscus)

4) Knee dislocation – an unusual and extremely

serious injury. – A knee dislocation occurs when the femur and tibia lose contact between each other. – occur with automobile

accidents, severe falls and sports injuries.

3. Tibiofibular joints (1) The superior (proximal) tibiofibular joint • between the lateral condyle of the tibia and the head of the fibula. (2) The inferior (distal) tibiofibular joint is formed by the medial side of the lower end of the fibula, and a rough concave surface on the lateral side of the tibia. (3) Interosseous membrane (tibiofibular syndesmosis) • between the tibia and the fibula.

4. Joints of foot (1) The ankle joint (or talocrural joint ) – is formed by the distal ends of

the tibia and fibula with the proximal end of the talus bone. where the foot and the leg meet – Strengthened the medial and lateral deltoid ligaments

(2) The intertarsal joints – the articulations found between the tarsal bones. – include joints: ① Talocalcaneal (subtalar joint) ② Talocalcaneonavicular ③ Calcaneocuboid

④ Cubonavicular ⑤ Cuneonavicular ⑥ Cuneocuboid

⑦ Intercuneiform

(2) The intertarsal joints – the articulations found between the tarsal bones. – include joints: – ⑧The transverse tarsal joint is formed by the articulation of the calcaneus with the cuboid (the calcaneocuboid joint), and the articulation of the talus with the navicular (the talocalcaneonavicular joint).

(3) The tarsometatarsal joints (or Lisfrance’s joint)

(4) The intermetatarsal joints (5) The metatarsophalangeal joints (6) The interphalangeal joints of foot

Ankle dislocation • The ankle dislocates as a result of a fall, motor-vehicle crash, or sporting injury. • In addition to the bony injury, there can be damage to blood vessels, nerves, and skin.

III. Disorders of Joints 1. Injury

（1） Sprain (扭伤)- stretching or tearing of a ligament

（2) Dislocation (脱位)

2. Inflammatory Conditions 1) Bursitis - inflammation of a bursa – Bursae are sacs of fluid that serve to protect boney prominences.

2. Inflammatory Conditions 2) Tendinitis (肌腱炎） - inflammation of a tendon sheath

3) Osteoarthritis （骨关节炎） - most common type of arthritis - degenerative condition of the articular cartilage - Enzymes wear down the cartilage matrix due to “wear and tear” - Symptoms may include joint pain, tenderness, stiffness, locking, and sometimes an effusion.

4) Rheumatoid Arthritis （ Rheumatoid Arthritis） - a chronic, systemic inflammatory disorder that may affect many tissues and organs - principally attacks synovial joints. - autoimmune in origin - lead to the destruction of articular cartilage and ankylosis (僵硬) of the joints.