Glenohumeral and Hip Joints Flashcards
How stable and mobile are the glomerohumeral and hip joints respectively ?
GH: UNSTABLE (Egg and spoon) but GREAT MOBILITY
Hip: STABLE but LIMITED MOBILITY
What are the ball and socket parts of the GH and hip joints ?
GH: Ball- Head of humerus
Socket- Glenoid cavity of scapula
Hip: Ball- Head of femur
Socket: Acetabulum of hip
Why is the GH joint less stable than the hip joint ?
Partly because the glenoid fossa is shallow
How much of the humeral head is in contact with the glenoid ?
1/3
Which muscles keep the GH joint in place ?
Rotator cuff muscles
What kind of connective tissue covers surfaces of the glenoid head of humerus ?
Hyaline cartilage
What structure attaches to the edge of the glenoid fossa and deepens the socket and helps to stabilise the joint ?
Glenoid labrum
What structure is the glenoid labrum fused with ?
Tendon of long head of biceps
Is the joint capsule of the GH joint loose or not ? Why ?
-Loose, especially inferiorly to allow abduction
Which structures support the joint capsule of the GH joint ?
Tendons of rotator cuff muscles
What structures is the joint capsule of GH attached to ?
Attached to glenoid fossa margin and labrum and anatomical neck of humerus.
Which structure does the capsule of the GH joint enclose (other than the joint itself) ?
It encloses the proximal attachment of long head of biceps.
What are the opening on the fibrous capsule of the GH joint ? What is the role of each?
- Biceps tendon passes through to its insertion.
- Subscapularis bursa
- Protects the subscapularis tendon from being damaged by the edge of the glenoid - Subacromial bursa
- Protects the supraspinatus tendon from being injured
What is a bursa ?
Sac-like, synovial fluid-filled cavity near joints which also help facilitate movement.
What are possible effects of bursitis ? Give an example specific to the GH joint.
May lead to degenerative changes in the associated tendons resulting in difficulty initiating certain movements (Example: supraspinatus tendon, inability to initiate abduction.)
What are the ligaments present around the GH joint ? Where are they located relative to the joint ?
Intrinsic (both anterior) ligaments:
Glenohumeral
Transverse humeral
Extrinsic (both superior)
Coracoacromial
Coracohumeral
How strong is each of the ligaments around the GH joint ?
Glenohumeral: weak
Coracoacromial: strong
Coracohumeral: strong
What is the function of the transverse humeral ligament ?
Keeps the biceps tendon in bicipital groove
What is the Coraco-acromial arch ?
coracoid process + acromion + coraco- acromial ligament
What is the function of the coraco-acromial arch ?
Prevents superior displacement of humerus
Why do most luxations occur inferiorly or posteriorly in the shoulder ?
Because there are no ligaments inferiorly or posteriorly.
Which of the ligaments surrounding the GH joint is considered a capsular ligament ?
Glenohumeral ligament
Why is the hip joint more stable than the GH joint ?
Because the acetabulum is deeper
What are the main components of the acetabulum ?
Acetabular fossa+Lunate surface
What type of connective tissue if the lunate surface of the acetabulum made of ?
Hyaline cartilage
What structure serves to further increase the depth of the acetabulum ? What connective tissue is this structure made of ?
Acetabular Labrum
Made of fibrocartillage
What is a major disadvantage of the acetabular
labrum ?
It may tear and cause pain
What is the Transverse acetabular ligament ? Why is this particularly important for children ?
“A portion of the acetabular labrum, which cross the acetabular notch, and convert it into a foramen through which the nutrient vessels enter the joint.”
Because if there is an injury to the femur, they will stop growing
What connective tissue is the head of the femur covered by ?
Hyaline cartilage except for the fovea capitis which is used for ligament attachment
What is another name of Acetabular Labrum ?
Cotyloid ligament
What is the hip joint attached ?
Attached to the acetabular rim, ligament transverse acetabular ligament, intertrochanteric line and neck of the femur
What does the capsule of the hip joint enclose ?
Everything, including the ligament of the head of the femur, but not the articular cartilage
How does the capsule manage to enclose the epiphysis of the femoral head completely ?
Because the synovial layers of the capsule sends retinacular fibres medially along the femoral neck towards the head.
What are the ligaments present around the hip joint ? Where are they located relative to the joint ?
Iliofemoral -Anterior and superior
Pubofemoral -Anterior and inferior
Ischiofemoral -Posterior
How strong are iliofeoral and ischiofemoral ligaments ?
Iliofemoral ligament- strongest
Ischiofemoral ligament- weakest
What are the functions of the iliofemoral and pubofemoral ligaments ?
Iliofemoral- Prevents hyperextension of hip joint during standing
Pubofemoral- Prevents overabduction of hip joint; tightens during abduction and extension of hip
Which of the hip joint ligaments are considered capsular ligaments ?
All three of them (iliofemoral, pubofemoral, ischiofemoral)
What is the zona orbicularis ?
Zone formed by circular winding of some deep fibres of the fibrous capsule around the neck of the femur
What is the function of the capsular ligaments of the hip during extension ?
- Prevent overextension
- Stabilize the joint
- Save energy during standing
In which way do capsular ligaments of the hip attach around the joint so they are taut in extension ?
Spiral around the joint and attach to femur so that they are taut in extension.
What is the vascular supply of the hip joint ?
Cruciate anastomosis, made by:
- Medial circumflex femoral artery (retinacular branches)
- Lateral circumflex femoral artery (retinacular branches)
- Obturator artery
Trochanteric anastomosis, made by:
- Medial circumflex femoral artery
- Lateral circumflex femoral artery
- Superior gluteal artery
- Inferior gluteal artery
What is a possible event which can affect blood supply to the head of the femur ?
Fracture of the femoral neck
What movements are possible at the hip joint ?
Flexion and Extension
Abduction and Adduction
Medial and Lateral Rotation
Circumduction
What movements are possible at the GH joint ?
Flexion and Extension
Abduction and Adduction
Medial and Lateral Rotation
Circumduction
What movements at the GH joint does pectoralis major allow ?
Adduction, medial rotation, flexion, extension
What are the flexors of the GH joint ?
Pectoralis Major, Deltoid (anterior/clavicular fibers), Biceps brachii (long head) and Coracobrachialis
What is the origin and insertion of pectoralis major ?
ORIGIN- Clavicular head (medial half of clavicle) Sternocostal head (sternum, superior six costal cartilages, aponeurosis of external oblique muscle)
INSERTION- Lateral lip of intertubercular sulcus (groove) of humerus
What is the origin and insertion of Deltoid (anterior/clavicular fibers) ?
ORIGIN- Lateral third of clavicle
INSERTION- Deltoid tuberosity of humerus
What is the origin and insertion of biceps brachii (long head) ?
ORIGIN- Supraglenoid tubercle
INSERTION- Tuberosity of radius and fascia of forearm via bicipital aponeurosis
What is the pectoralis major innervated by ?
Medial and lateral pectoral nerves
Which muscle makes up the anterior axillary fold ?
Pectoralis Major
What are coracobrachialis and biceps (long head) innervated by ?
Musculocutaneous nerve
What are the extensors of the GH joint ?
Latissimus Dorsi, Triceps (long head), Deltoid (posterior/spinal fibers), Teres Major, Pectoralis Major
What movements at the GH joint does latissimus dorsi allow ?
Only extension
What muscle forms the posterior axillary fold ?
Latissimus Dorsi
What is the latissimus Dorsi innervated by ?
Thoracodorsal nerve
What are all the movements allowed by the long head of the triceps ?
- Stabilises adducted GH joint
- Extends GH joint
- Extends arm
What is the origin and insertion of the latissimus dorsi ?
ORIGIN-
Spinous processes of inferior six thoracic vertebrae, thoracolumbar fascia, iliac crest, and inferior three or four ribs
INSERTION-
Floor of intertubercular sulcus (groove) of humerus
What is the origin and insertion of the deltoid (posterior/spinal fibers) ?
ORIGIN-
Acromion
INSERTION-
Deltoid tuberosity of humerus
What is the origin and insertion of the triceps (long head) ?
ORIGIN-
Infragleoid tubercle of the scapula
INSERTION-
Olecranon
What is the origin and insertion of the teres major ?
ORIGIN-
Inferior part of lateral border of scapula
INSERTION-
Medial lip of intertubercular sulcus of humerus
What is the exact role of teres major and pectoralis major in the extension of the arm ?
Extend the already flexed arm
What are the rotator cuff muscles ?
Supraspinatus, Infraspinatus, Teres minor, Subscapularis (SITS)
Where do all rotator cuff muscles originate/insert ?
ORIGIN-
Scapula
INSERTION-
Humerus
What is a scapulohumeral muscle ? Give examples.
Intrinsic shoulder muscle
E.g. Rotator Cuff Muscles
How are rotator cuff muscles arranged around the GH joint ?
Form a musculotendinous cuff around the glenohumeral joint (tendons blend with the capsule of the shoulder joint)
What movement are rotator cuff muscles responsible for ? Which muscle is an exception to that ?
Rotation of the arm
Supraspinatus
How do rotator cuff muscles stabilise the shoulder joint ?
By pulling the head of the humerus into the glenoid fossa
What is the main stabilising factor at the GH joint ?
The tone of rotator cuff muscles
What movement is supraspinatus responsible for ?
Initiation of abduction (first 15 degrees)
What movement is supraspinatus responsible for ?
Lateral rotation
What movement is teres minor responsible for ?
Lateral rotation
What movement is subscapularis responsible for ?
Medial rotation
Where is each of the rotator cuff muscles located, relative to the scapula and humerus ?
Supraspinatus, infraspinatus teres minor: from the posterior aspect and lateral border of the scapula to the greater tubercle of the humerus
Subscapularis: from the anterior aspect of the scapula to the lesser tubercle of the humerus
What is each of the rotator cuff muscles innervated by ?
Supraspinatus and infraspinatus: suprascapular nerve
Teres minor: suprascapular nerve
Subscapularis: superior and inferior subscapular nerves
What are abductors of the GH joint ?
Deltoid (middle/spinal fibers) and Supraspinatus (initiates the first 15 degrees)
What are the adductors of the GH joint ?
Teres Major, Coracobrachialis, Lat Dorsi and Pec Major
What is the origin and insertion of the deltoid (middle/spinal nerves) ?
ORIGIN-
Clavicle, acromion and spine of scapula
INSERTION-
Deltoid tuberosity of the humerus
How is the deltoid (middle/spinal fibers) innervated ?
Axillary nerve
What are all the movements performed by the deltoid muscle ? Which part of the deltoid is responsible for which movement ?
- Abduction (middle/spinal fibers-acromial part)
- Flexion and medial rotation (anterior/clavicular fibers-clavicular part)
- Extension and lateral rotation (posterior/spinal fibers-spinal part)
What are all the movements performed by the teres major muscle ?
- Adducts
- Medially rotates humerus
- Extends flexed arm
What is the teres major innervated by ?
Lower subscapular nerve
What are all the movements performed by the coracobrachialis muscle ?
- Adducts
- Weakly flexes GH
- Resists dislocation of shoulder joint
What is the coracobrachialis muscle pierced and innervated by ?
Musculocutaneous nerve
Where is the coracobrachialis muscle relative to humerus and scapula ?
Between the coracoid process and the humerus, between brachialis and triceps
What is the origin and insertion of the acromial part (middle/spinal fibers) of the deltoid ?
ORIGIN-
Spine of scapula
INSERTION-
Deltoid tuberosity of humerus
What is the origin and insertion of the supraspinatus muscle ?
ORIGIN-
Supraspinous fossa of scapula
INSERTION-
Superior facet of greater tubercle of humerus
What is the origin and insertion of the coracobrachialis muscle ?
ORIGIN-
Coracoid process
INSERTION-
Medial side of middle humerus
Which movement of the humerus increases the range of abduction ?
Lateral rotation
Which muscles of the back also contribute to abduction of the GH joint ?
Trapezius
Serratus anterior
What are the prime movers of each movement at the GH joint ?
Abduction: Deltoid Adduction: Pec Major and Lat Dorsi Flexion: Pec Major and Deltoid Extension: Deltoid Lateral rotation: Infraspinatus Medial rotation: Subscapularis
What are the gateways to the scapular region ?
Suprascapular notch
Quandrangular space
Upper triangular space
Lower triangular space (triangular interval)
What passes through the Suprascapular notch ?
• Suprascapular and Suprascapular artery
What is the quadrangular space delimited by ? What passes through it ?
Humerus, long head of triceps, teres minor, teres major
- Axillary nerve
- Posterior circumflex humeral artery
What is the upper triangular space delimited by ? What passes through it ?
Long head of triceps, teres minor, teres major
• Circumflex scapular artery
What is the lower triangular space delimited by ? What passes through it ?
Long head of triceps, teres major, humerus
• Radial nerve and profunda brachii artery
What are the flexors of the hip ?
Iliacus and Psoas major (together = Iliopsoas)
Sartorius and Rectus Femoris (flex hip but also act on knee joint)
Where do muscles flexing the hip pass, relative to the pelvis, femur and hip joint ?
They pass from the pelvis to the femur, anterior to the hip joint
What space do Iliacus and psoas major pass through to get into the femoral region ?
Retro-inguinal space
What two compartments does the fascia of psoas major create in the femoral region ?
Muscular and vascular compartments
Which structures are found in the muscular compartment formed by the fascia of psoas major ?
Femoral nerve and iliopsoas (Iliacus + psoas major)
What is the origin and insertion of the iliacus ?
ORIGIN-
Posterior abdominal wall (iliac fossa)
INSERTION-
Lesser trochanter of femur
What is the origin and insertion of the psoas major ?
ORIGIN-
Posterior abdominal wall (lumbar transverse processes, intervertebral discs, and adjacent bodies from TXII to LV and tendinous arches between these points)
INSERTION-
Lesser trochanter of femur
What is the origin and insertion of the Rectus Femoris (straight and reflected heads) ?
ORIGIN-
Anterior superior iliac spine, ilium just superior to the acetabulum
INSERTION-
Base of patella via common Quadriceps femoris tendon
What is the origin and insertion of the Sartorius ?
ORIGIN-
Anterior superior iliac spine
INSERTION-
Medial surface of medial tibial condyle (pes anserinus)
What is the origin and insertion of the Pectineus ?
ORIGIN-
Superior ramus of pubis
INSERTION-
Pectineal line of femur
What are all the flexors of the hip ?
Iliacus, psoas major, sartorius, pectineus, rectus femoris, Tensor fascia latae
What are the flexors of the hip innervated by ?
-Iliacus, psoas major, sartorius, pectineus, rectus femoris, Tensor fascia latae - by the femoral nerve
-Psoas major (L1-L3)
What are the adductors of the hip ?
Pectineus
Adductor magnus, longus, and brevis
Gracilis
Obturator externus
What is the origin and insertion of the Adductor Longus ?
ORIGIN-
Body of pubis inferior to pubic crest
INSERTION-
Middle third of linea aspera of femur
What is the origin and insertion of the Adductor Brevis ?
ORIGIN-
Body and inferior ramus of pubis
INSERTION-
Proximal part of linea aspera of femur
What is the origin and insertion of the Adductor Magnus ?
ORIGIN-
Adductor part: inferior ramus of pubis, ramus of ischium
Hamstring part: ischial tuberosity
INSERTION-
Linea aspera, medial supracondylar line, adductor tubercle of femur
What is the origin and insertion of Gracilis ?
ORIGIN-
Body and inferior ramus of pubis
INSERTION-
Medial surface of medial tibial condyle (pes anserinus)
What is the origin and insertion of Obturator externus ?
ORIGIN-
Margins of obturator foramen and external surface of obturator membrane
INSERTION-
Trochanteric fossa of femur
What are the adductors of the hip innervated by ?
Pectineus- Femoral nerve Adductor magnus- Tibial and obturator nerve Adductor longus- Obturator nerve Adductor brevis- Obturator nerve Gracilis- Obturator nerve Obturator externus- Obturator nerve
Where do muscles extending the hip pass, relative to the pelvis, femur and hip joint ?
Muscles that pass from the pelvis to the lower limb, posterior to the hip joint
Where are the hamstring muscles found, relative to surrounding structures ?
Between the ischial tuberosity and the tibia and fibula
What muscles are included amongst hamstring muscles ?
Biceps femoris, semitendinous and semimembraneous
What are all the movements the hamstring muscles are responsible for ?
Extend the hip
Flex the leg
Extend the body if the thigh is fixed
What are the extensors of the hip ?
Guteus Maximus (prime mover) Hamstring muscles (biceps femoris, semitendinous and semimembraneous) Adductor magnus
What are all the movements allowed by the gluteus maximus ?
Extension of the hip when standing from sitting and climbing stairs
Externally rotates the femur
Abducts the femur
Locks the knee
Which structure is particularly important in locking the knee (besides gluteus maximus) ?
Iliotibial tract
What is the origin and insertion of the biceps femoris ?
ORIGIN:
Ischial tuberosity and lateral lip of linea aspera
INSERTION:
Head of fibula
What is the origin and insertion of the semitendinous muscle ?
ORIGIN:
Ischial tuberosity
INSERTION:
Medial surface of medial tibial condyle (pes anserinus)
What is the origin and insertion of the semimembraneous muscle ?
ORIGIN:
Ischial tuberosity
INSERTION:
Medial condyle of tibia; reflected attachment forms oblique popliteal ligament
What is the origin and insertion of the gluteus maximus ?
ORIGIN:
Ilium posterior to posterior gluteal line; dorsal surface of sacrum and coccyx; and sacrotuberous ligament
INSERTION:
Iliotibial tract and gluteal tuberosity
How are the extensors of the hip innervated ?
Guteus Maximus - Inferior gluteal nerve
Biceps femoris- Sciatic Nerve
Semitendinous- Sciatic Nerve
Semimembraneous- Sciatic Nerve
Adductor magnus- Sciatic Nerve
Which of the hamstring muscles act on both knee and hip joints ? How come ?
Semitendinous, semimembranous and long head of biceps femoris
NOT short head of biceps femoris
Because all hamstrings except the short head of the biceps femoris originate from the ischial tuberosity
Where do muscles abducting the hip pass, relative to the pelvis, femur and hip joint ?
Pass from the pelvis to the femur, lying lateral to the hip joint
What are the muscles which are responsible for abduction of the hip joint ?
Gluteus medius
Gluteus minimus
Tensor fascia latae
What do the fascia lata and gluteus maximus attach to, to aid gluteus medius and gluteus minimus in abducting the hip ?
Iliotibial tract
Muscles performing which two movements at the hip keep the pelvis level when walking or standing on one level ?
Abduction and adduction ( All abductors of one side keep pelvis level when limb of the same side is weight bearing)
What is the origin and insertion of the gluteus medius ?
ORIGIN-
External surface of ilium between anterior and posterior gluteal lines
INSERTION-
Greater trochanter of femur
What is the origin and insertion of the gluteus minimus ?
ORIGIN-
External surface of ilium between anterior and inferior gluteal lines
INSERTION-
Greater trochanter of femur
What is the origin and insertion of the Tensor fascia latae ?
ORIGIN-
Anterior superior iliac spine; anterior part of iliac crest
INSERTION-
Lateral condyle of tibia via Iliotibial tract
What are the abductor muscles innervated by ?
Superior gluteal nerve
Where do muscles laterally rotating the hip pass, relative to the pelvis, femur and hip joint ?
Pass from the pelvis to the femur, lying close to and posterior to the hip joint
What are the lateral rotators of the hip ?
Inferior gemellus Obturator internus Obturator externus Piriformis Quadratus femoris Superior gemellus
What are the muscles responsible for lateral rotation innervated by ?
Obturator internus and superior gemellus - Obturator internus nerve
Inferior gemellus and quadratus femoris - Nerve to quadratus femoris
Piriformis - Anterior branches of S1-S2
Which movement allows the foot to keep pointing forward during walking ?
Lateral rotation of the femur
What are the bounds of the femoral triangle ?
Inguinal ligament (base), the sartorius muscle laterally (apex), and the adductor longus muscle medially
Floor: pectineus (medially) and the iliopsoas (laterally)
Roof: fascia lata (deep fascia of the thigh), subcutaneous tissue and skin
Which neurovascular structures does the femoral sheath contain ?
Femoral artery and vein BUT NOT the nerve.
Where is the adductor canal present within the femoral triangle ?
At the apex of the triangle
What are other names for the adductor canal in the hip ?
Subsartorial canal, Hunter’s Canal
Which neurovascular structures does the adductor canal of the hip contain ?
From medial to lateral, deep inguinal lymph nodes (in femoral canal), femoral vein, femoral artery and femoral nerve.
Where is the femoral canal found ?
Between the medial wall of the femoral sheath and the femoral vein
What is the shape of the femoral canal ?
Conical
What does the femoral canal contain ?
Deep inguinal lymph nodes
What is a major role of the femoral canal, besides containing deep inguinal lymph nodes ?
Allows the femoral vein to expand
What is the base of the femoral canal (opening) called ?
Femoral ring
What is a possible consequence of the weak nature of the femoral ring ?
Femoral Hernia